# Spectroscopic study of Ba and CEMP-s stars111Based [in part] on data
collected at Subaru Telescope, which is operated by the National Astronomical
Observatory of Japan.222[Part of] the data are retrieved from the JVO portal
(http://jvo.nao.ac.jp/portal) operated by the NAOJ: Mass distribution of AGB
progenitors

Partha Pratim Goswami  Indian Institute of Astrophysics, Koramangala,
Bangalore 560034, India<EMAIL_ADDRESS><EMAIL_ADDRESS>Pondicherry
University, R.V. Nagar, Kalapet, 605014 Puducherry, India  Aruna Goswami
Indian Institute of Astrophysics, Koramangala, Bangalore 560034, India;
<EMAIL_ADDRESS><EMAIL_ADDRESS>
(Received —; Revised —)

###### Abstract

We have performed detailed high-resolution spectroscopic analysis on seven
metal-poor stars (BD+75 348, BD+09 3019, HD238020, HE0319–0215, HE0507–1653,
HE0930–0018, HE1023–1504) and derived their atmospheric parameters Teff,
log$g$, [Fe/H], and mictroturbulent velocity ($\xi$). The metallicity range is
found to be –2.57$<$[Fe/H]$<$–0.42. The elemental abundances of 17 light
elements and 12 heavy elements are estimated. We have classified BD+75 348 and
BD+09 3019 as strong Ba stars, HD238020 as a mild Ba star, and the remaining
four objects as CEMP-s stars. We have estimated the masses of the stars from
Hertzsprung-Russel (HR) diagram, and, compiling the data of 205 Ba stars from
literature, estimated the mass distribution of Ba stars. We have also
estimated the initial masses of the companion AGBs of the program stars as
well as the masses of the companion AGBs of 159 Ba and 36 CEMP-s stars from
literature, with the help of a parametric-model-based analysis using FRUITY
models. While the primary mass distribution of mild Ba stars peaks at 3.7 M⊙,
for the strong Ba stars the peak appears at 2.5 M⊙. We, therefore, propose
that the initial masses of the progenitor AGBs dominantly control the
formation of mild and strong Ba stars. However, a clear overlap, in the range
1.3–4.0 M⊙, noticed between the progenitor masses of both the subclasses of Ba
stars, may indicate that other factors, such as metallicities and the orbital
periods, may also have significant contributions. The progenitor AGBs’ mass
distribution of CEMP-s stars is found to peak at 2.03 M⊙.

stars: individual (BD+75 348, BD+09 3019, HD 238020, HE 0319–0215, HE
0507–1653, HE 0930–0018, HE 1023–1504)—stars: Abundances—stars: carbon—stars:
chemically peculiar

††journal: AJ

##  1 Introduction

Barium (Ba) stars and a subclass of carbon enhanced metal-poor (CEMP) stars,
known as CEMP-s stars, exhibit enhanced abundances of elements produced by
slow (s-) neutron (n)-capture process. Ba stars, first recognized by Bidelman
& Keenan (1951), are identified by the presence of strong absorption lines of
Ba II at 4554 Å & Sr II at 4077 Å in their spectra (Warner, 1965). C2, CN, and
CH molecular bands are also prominent in Ba stars. Depending on the types of
neutron-capture elements present, carbon enhanced metal-poor stars are divided
into four subclasses (Beers & Christlieb, 2005; Frebel, 2018; Goswami et al.,
2021), namely CEMP-s stars (enriched with s-process elements), CEMP-r stars
(enriched with elements produced in rapid n-capture process or r-process),
CEMP-r/s stars (enriched with elements produced in intermediate n-capture
process or i-process (Cowan & Rose, 1977; Herwig et al., 2011; Doherty et al.,
2015; Hampel et al., 2016; Banerjee et al., 2018; Denissenkov et al., 2019;
Goswami et al., 2021)) and CEMP-no stars (not enriched with n-capture
elements).

The formation scenario of CEMP-s (Spite et al., 2013) and Ba (Cseh et al.,
2018, 2022) stars is similar. Both the types of stars (secondary) are
extrinsic in nature and they get the s-process rich material through mass-
transfer from a more massive companion (primary), which evolves faster and
produces s-process elements in the AGB phase. CEMP-s and Ba stars are known to
be in binary systems with invisible white-dwarf companions. The binary nature
of these stars is proved by long-term radial velocity monitoring programs
(McClure, 1983, 1984; McClure & Woodsworth, 1990; Lucatello et al., 2005;
Starkenburg et al., 2014; Jorissen et al., 2016; Hansen et al., 2016a). Recent
studies (Roederer et al., 2016; Hampel et al., 2016, 2019; Koch et al., 2019;
Goswami & Goswami, 2020; Goswami et al., 2021) have revealed that one of the
formation scenarios for CEMP-r/s stars might also be the binary evolution with
contamination by AGB yields similar to the CEMP-s stars. The different
physical conditions between the production of s- and i-process elements in AGB
stars are still under debate. In our recent study (Goswami & Goswami, 2021),
we have reported an object HE 1005–1439, abundance pattern of which shows
contamination by both s- and i-processes. We proposed that in AGB stars, s-
and i-process can take place in succession without masking the signatures of
each other. Although the formation scenarios of Ba, CEMP-s and CEMP-r/s stars
are similar, in this paper, we will discuss only CEMP-s and Ba stars.

Warner (1965) classified the Ba stars with Ba index 1 – 5 based on the
strength of Ba II 4554 Å line. Ba1 and Ba5 signify stars showing the weakest
and the strongest Ba lines respectively. Later, several authors (Lu, 1991;
Jorissen et al., 1998; Yang et al., 2016; Escorza et al., 2017) used this Ba
index to classify the Ba stars into two groups: mild Ba stars and strong Ba
stars. The overabundance of n-capture elements is higher in strong Ba stars
than that of mild Ba stars. In the Literature, lower enhancement of heavy
elements in mild Ba stars are explained by two plausible formation scenarios-
i) a longer orbital period of the binary system and ii) relatively weaker
neutron-exposure in the AGB companion that pollutes the star (Yang et al.,
2016).

In this paper, we have reported the elemental abundances of seven stars BD+75
348, BD+09 3019, HD 238020, HE 0319–0215, HE 0507–1653, HE 0930–0018 and HE
1023–1504 based on detailed high-resolution spectroscopic analysis. We have
estimated the masses of the program stars and their AGB companions. We have
estimated the masses of several Ba stars found in the literature to find the
mass distribution of these stars. We have also derived the initial mass
distribution of the AGB companions of these Ba stars and a sample of
literature CEMP-s stars. Here, we refer the stars (Ba and CEMP-s) that we are
observing now as secondary stars and their companion AGBs as primary stars.

We have organized the paper as follows. In Section 2 we briefly discuss the
summary of the earlier studies available in literature on our program stars.
The details of the sources of the spectra are presented in Section 3. In
Section 4, we have discussed the method of determination of photometric
temperatures. Section 5 discusses the method of estimation of radial velocity
and derivation of stellar atmospheric parameters of the program stars. In
Section 6 we have presented the Abundance analysis results (Section 6.1) and
the kinematic analysis of the program stars (Section 6.2). In Section 7 we
have presented i) the classification schemes of Ba and CEMP-s stars (Section
7.1), ii) classification of the program stars (Section 7.2), iii)
determination of masses of the program stars (Section 7.3), iv) determination
of masses of the primary companions (AGB progenitors) of the program stars
(Section 7.4), v) a comprehensive discussion on the mass distributions of a
literature sample of Ba stars and their AGB progenitors and the mass
distribution of the AGB progenitors of a literature sample of CEMP-s stars
(Section 7.5) and vi) formation scenarios of mild and strong Ba stars (Section
7.6). Section 8 draws the conclusions.

##  2 Previous Studies of the program stars

###  2.1 BD+09 3019, HD 238020, HE 0930–0018 & HE 1023–1504

BD+09 3019 is included in the carbon star catalog of Stephenson (1989), CH
star catalog of Bartkevicius (1996) and the carbon star catalogue of Ji et al.
(2016) from LAMOST DR2 data. HD 238020 is included in the CH star catalogue of
Bartkevicius (1996). The list of faint high-latitude carbon stars of
Christlieb et al. (2001) includes HE 0930–0018 and HE 1023–1504. Atmospheric
parameters of BD+09 3019 and HE 0930–0018 are not reported previously in the
literature. McDonald et al. (2012) derived the effective temperatures of HD
238020 using the spectral energy distribution (SED) method of temperature
calibration. Our estimate of temperature is more by 115 K for HD 238020 than
that of McDonald et al. (2012). Kennedy et al. (2011) estimated the
atmospheric parameters and the abundance of oxygen for HE 1023–1504. Our
estimates of effective temperature and log $g$ closely match the estimates of
Kennedy et al. (2011). However, the metallicity ([Fe/H]) estimated by Kennedy
et al. (2011) is $\sim$ 0.8 dex lower than that of our estimate. In this work,
first-time abundance estimates of several light elements from C through Zn and
neutron-capture elements from Sr through Hf are presented for these four
objects based on high-resolution spectroscopic analysis.

###  2.2 BD+75 348, HE 0319–0215 & HE 0507–1653

BD+75 348 is listed in the carbon star catalog of Stephenson (1989) and CH
star catalog of Bartkevicius (1996). Bergeat et al. (2001) and McDonald et al.
(2012) estimated the effective temperature of BD+75 348 using the SED method
of temperature calibration. Začs et al. (2000) derived the atmospheric
parameters as well as abundances of ten light and nine heavy elements for
BD+75 348. The literature values of Teff for BD+75 348 range from 4700–4900 K.
Our estimate of Teff ($\sim$ 4840 K) falls within the range. HE 0319–0215 & HE
0507–1653 are included in the list of the faint high-latitude carbon stars of
Christlieb et al. (2001). Goswami (2005) estimated the 12C/13C ratio for HE
0319–0215 (12C/13C $\sim$ 4.7) and HE 0507–1653 (12C/13C $\sim$ 6.7) based on
medium-resolution spectra. From the studies of Hansen et al. (2016b) on HE
0319–0215 and Hansen et al. (2016b) and Jorissen et al. (2016) on HE 0507–1653
it is found that both the objects exhibit radial velocity variations with
periods of 3078 days for HE 0319–0215 and 405 days for HE 0507–1653 confirming
their binary nature. Kennedy et al. (2011) derived atmospheric parameters and
abundance of oxygen for HE 0319–0215. Hansen et al. (2016b) reported [Fe/H] =
–2.30, [C/Fe] = 2.0, [Ba/Fe] = 0.52 for HE 0319–0215. Karinkuzhi et al. (2021)
also derived the atmospheric parameters and elemental abundances of HE
0319–0215 and reported the object as a CEMP-r/s star. However, the estimates
of [Fe/H] and [Ba/Fe] by the studies of Hansen et al. (2016b) and Karinkuzhi
et al. (2021) differ by $\sim$ 0.6 dex and $\sim$ 1.23 dex respectively. These
discrepancies in the literature values compelled us to re-investigate this
object in detail using high-resolution spectroscopy. Schuler et al. (2008)
reported [Fe/H] = –1.42, [C/Fe] = 1.33 and [N/Fe] = 1.20 for HE 0507–1653.
Aoki et al. (2007) and Yong et al. (2013) derived atmospheric parameters and
abundances of C, N, Na, Mg, Ca, Sc, Ti, Cr, Ni, Zn and Ba for HE 0507–1653.
Karinkuzhi et al. (2021) reported this object as a CEMP-s star. However, this
object also shows discrepancies in the atmospheric parameters and the
abundance of Ba obtained by different groups. For instance, the ranges of
Teff, log $g$ and [Fe/H] are 4880 to 5035 K, 1.50 to 2.40 dex and –1.81 to
–1.32 dex, respectively, and the [Ba/Fe] ranges from 1.56 – 1.89 dex. These
differences prompted us to study this object in detail.

##  3 Source of spectra

We acquired high-resolution spectra of BD+09 3019, BD+75 348, and HD 238020
using the Hanle Echelle SPectrograph (HESP) attached to the 2m Himalayan
Chandra Telescope (HCT) at the Indian Astronomical Observatory (IAO), Hanle. A
4K $\times$ 4K CCD detector with a pixel size of 15 $\micron$ is used. The
wavelength of the spectra covers 3500–10 000 Å at a spectral resolution
($\lambda$/$\delta\lambda$) of 60 000. For data reduction, we have used Image
Reduction and Analysis Facility (IRAF) software packages following a standard
procedure. We have applied spectroscopic data reduction procedures such as
trimming, bias subtraction, flat normalization, and extraction to the raw
data. A high-resolution Th-Ar arc spectrum is used for wavelength calibration.
High-resolution spectra (R $\sim$ 50 000) of HE 0319–0215, HE 0507–1653, HE
0930–0018 & HE 1023–1504 are taken from the SUBARU
archive333http://jvo.nao.ac.jp/portal acquired using the High Dispersion
Spectrograph (HDS) (Noguchi et al., 2002) attached to the 8.2 m Subaru
Telescope. For HE 0319–0215, HE 0930–0018 & HE 1023–1504, the wavelength
coverage of the spectra spans from about 4020 to 6775 Å, with a gap of about
100 Å (from 5340 to 5440 Å). The wavelength coverage of the spectra of HE
0507–1653 spans from 4090 to 6870 Å, with a gap of 80 Å (from 5430 to 5510 Å).
The gap in the wavelength coverage appears due to the physical spacing of the
CCD detectors. We have continuum fitted the spectra using the task continuum
in IRAF. The sample spectra of the program stars in the wavelength region
5160–5190 Å are shown in Figure 1. The basic data for the program stars are
presented in Table 1.

Figure 1:  Sample spectra of the program stars in the wavelength region 5160 –
5190 Å Table 1:  Basic data for the program stars

Star Name |  RA$(2000)$ |  Dec.$(2000)$ | B | V | J | H | K | Exposure | Date of Obs. | Source | S/N | S/N
---|---|---|---|---|---|---|---|---|---|---|---|---
|  |  |  |  |  |  |  | (seconds) |  | of spectrum | (4000 Å) | (6000 Å)
BD+75 348 | 08 46 11.64 | +74 32 31.24 | 10.63 | 9.54 | 7.84 | 7.33 | 7.24 | 2400 | 08-03-2018 | HESP/HCT | 50 | 150
BD+09 3019 | 15 18 32.06 | 09 06 09.74 | 12.04 | 10.82 | 7.99 | 7.24 | 6.99 | 2700 | 24-05-2018 | HESP/HCT | 20 | 40
HD 238020 | 11 36 10.99 | +56 50 17.66 | 9.34 | 8.49 | 6.90 | 6.51 | 6.38 | 1800 | 06-05-2017 | HESP/HCT | 70 | 200
HE 0319–0215 | 03 21 46.26 | –02 04 33.95 | 15.03 | 13.60 | 11.79 | 11.22 | 11.06 | 1800 | 08-12-2003 | HDS/SUBARU | 40 | 70
HE 0507–1653 | 05 09 16.56 | –16 50 04.69 | 13.63 | 12.51 | 10.88 | 10.43 | 10.32 | 1200 | 26-10-2002 | HDS/SUBARU | 40 | 75
HE 0930–0018 | 09 33 24.63 | –00 31 44.60 | 16.13 | 14.70 | 12.19 | 11.55 | 11.34 | 1800 | 09-12-2003 | HDS/SUBARU | 10 | 30
HE 1023–1504 | 10 25 55.55 | –15 19 17.08 | 16.26 | 14.40 | 12.32 | 11.61 | 11.42 | 1200 | 27-02-2005 | HDS/SUBARU | 7 | 25

##  4 Photometric Temperatures

We have used broad-band colors, optical, and IR to determine the photometric
temperatures of the program stars with color-temperature calibrations, based
on the infrared flux method (IRFM), available for main-sequence (Alonso et
al., 1996) and giant stars (Alonso et al., 1999). We have taken the 2MASS
photometric magnitudes for J, H, and K from Cutri et al. (2003). We have
followed the same procedure described in Goswami et al. (2006, 2015) and
Goswami et al. (2021) as briefly outlined below. The photometric temperatures
of the program stars corresponding to J–H and V–K colors are estimated at
different assumed metallicity values. The estimated photometric temperatures
are listed in Table 2. In order to select the model atmospheres to estimate
the spectroscopic temperatures, we have used Teff(J–K) as an initial guess as
this temperature is independent of metallicity (Alonso et al., 1996, 1999).

Table 2: Temperatures from photometry

Star Name | $T_{eff}$ | $T_{eff}$ | $T_{eff}$ | $T_{eff}$ | $T_{eff}$ | $T_{eff}$ |  Teff | $T_{eff}$ |  Teff |  Teff |  Teff | Spectroscopic
---|---|---|---|---|---|---|---|---|---|---|---|---
|  | $(-0.5)$ | $(-1.0)$ | $(-1.5)$ | $(-2.0)$ | $(-2.5)$ | $(-0.5)$ | $(-1.0)$ | $(-1.5)$ | $(-2.0)$ | $(-2.5)$ | estimates
| (J–K) | (J–H) | (J–H) | (J–H) | (J–H) | (J–H) | (V–K) | (V–K) | (V–K) | (V–K) | (V–K) |
BD+75 348 | 4856 | 4867 | 4891 | 4891 | 4867 | 4820 | 4749 | 4736 | 4729 | 4728 | 4733 | 4840
BD+09 3019 | 3879 | 4038 | 4051 | 4047 | 4027 | - | 3810 | 3795 | - | - | - | 4220
HD 238020 | 5085 | 5350 | 5382 | 5384 | 5358 | 5304 | 4941 | 4931 | 4928 | 4931 | 4941 | 5150
HE 0319–0215 | 4479 | 4616 | 4636 | 4635 | 4612 | 4568 | 4530 | 4517 | 4510 | 4510 | 4515 | 4650
HE 0507–1653 | 4935 | 5078 | 5105 | 5106 | 5081 | 5031 | 4855 | 4844 | 4839 | 4840 | 4848 | 4970
HE 0930$-$0018 | 4164 | 4354 | 4370 | 4368 | 4346 | 4306 | 4002 | 3988 | 3979 | 3974 | - | 4190
HE 1023–1504 | 4062 | 4144 | 4157 | 4154 | 4133 | - | 4211 | 4198 | 4190 | 4187 | - | 4440

The numbers in the parenthesis below $T_{eff}$ indicate the metallicity values
at which the temperatures are calculated.
Temperatures are given in Kelvin.

##  5 Radial velocities and stellar atmospheric parameters

We have measured the radial velocities of the program stars using Doppler’s
formula from the shifts of the elemental absorption lines from the lab
wavelengths. For this purpose, we have chosen a large number of clean and
unblended spectral lines of different elements in each star and compared them
with the rest frame laboratory wavelength taking the spectra of Arcturus
(Hinkle et al., 2000) as a template. As Arcturus belongs to the giant class
and has a comparable temperature as the program stars, we have chosen Arcturus
for the comparison to have homogeneity in the analysis. We have also used the
FXCOR package in IRAF and cross-checked our measurements from line-to-line
analysis to the measurements provided by FXCOR. The measured radial
velocities, after correcting for heliocentric motion, and the standard
deviations from the mean value are presented in Table 3, along with the radial
velocity information provided by Gaia Collaboration et al. (2018). For the
stars HE 0930–0018 and HE 1023–1504, radial velocities are not reported in
Gaia Collaboration et al. (2018). However, the other five stars show
significant differences in radial velocities estimated by us with that of Gaia
Collaboration et al. (2018), implying the possibility of the stars being part
of a binary system with a now invisible companion.

Stellar atmospheric parameters, Teff, log $g$, micro-turbulent velocity
($\xi$), and [Fe/H] are derived using the method described in Goswami et al.
(2021) as briefly discussed below. For this analysis, we have chosen a set of
clean and unblended Fe I and Fe II lines (Table 4) from each star. The
excitation potentials of the lines range from 0.0 to 6.0 eV. The atomic line
information is taken from the kurucz atomic line
database444https://lweb.cfa.harvard.edu/amp/ampdata/kurucz23/sekur.html. After
strong filtration of the clean lines, we have considered (85, 12), (36, 3),
(136, 17), (30, 5), (36, 4), (19, 3), and (20, 2) numbers of (Fe I, Fe II)
lines in the spectra of BD+75 348, BD+09 3019, HD 238020, HE 0319–0215, HE
0507–1653, HE 0930–0018 and HE 1023–1504 respectively. For our analysis, we
have used the code MOOG (Sneden, 1973) in its updated 2013 version. MOOG
assumes conditions of local thermodynamic equilibrium (LTE). We have selected
the model atmospheres from the Kurucz grid of model
atmospheres555http://kurucz.harvard.edu/grids.html with no convective
overshooting, and the solar abundances are taken from Asplund et al. (2009).
For determining the effective temperatures and micro-turbulent velocities of
the program stars, we have used the conventional methods of excitation
potential balance and equivalent width balance, respectively. The surface
gravities of the program stars are determined by using the method of
ionization equilibrium balance, in which the abundance of Fe measured from Fe
I and Fe II lines are equated to fix the value of log $g$. The abundance of Fe
derived from Fe I and Fe II lines gives the metallicities of the stars. The
atmospheric parameters of the program stars, along with the available
literature values, are presented in Table 5.

Table 3: Radial velocities of the program stars.

Star Name |  Vr |  Vr
---|---|---
|  (Km s-1) |  (Km s-1)
| (Our estimates) | (a)
BD+75 348 |  57.70 $\pm$ 1.72 |  56.91 $\pm$ 2.21
BD+09 3019 |  –9.50 $\pm$ 1.77 |  8.21 $\pm$ 0.65
HD 238020 |  –24.62 $\pm$ 3.07 |  –16.04 $\pm$ 0.15
HE 0319$-$0215 |  –257.43 $\pm$ 0.61 |  –232.33 $\pm$ 4.38
HE 0507–1653 |  349.81 $\pm$ 0.72 |  353.53 $\pm$ 2.55
HE 0930$-$0018 |  45.73 $\pm$ 0.68 | -
HE 1023–1504 |  –226.15 $\pm$ 0.39 | -

References: (a) Gaia Collaboration et al. (2018)

Table 4: Equivalent widths (in mÅ) of Fe lines used for deriving atmospheric
parameters.

Wavelength | Element |  Elow | log gf | BD+75 348 | BD+09 3019 | HD 238020 | HE 0319–0215 | HE 0507–1653 | HE 0930–0018 | HE 1023–1504
---|---|---|---|---|---|---|---|---|---|---
(Å) |  | (eV) |  |  |  |  |  |  |  |
4187.04 | Fe I | 2.45 | –0.548 | - | - | - | - | 124.8 (6.12) | - | -
4202.03 |  | 1.48 | –0.708 | - | - | - | - | 179.4 (6.02) | - | -
4203.57 |  | 1.01 | –3.869 | - | - | 73.1 (6.72) | - | - | - | -

The numbers in the parenthesis in columns 5 to 11 give the derived abundances
from the respective line.
Note: This table is available in its entirety online only. A portion is shown
here for guidance regarding its form and content.

Table 5: The derived atmospheric parameters of our program stars and
literature values.

Star Name |  Teff | log g | $\xi$ | [Fe I/H] | [Fe II/H] | [Fe/H] | Ref
---|---|---|---|---|---|---|---
| (K) | (cgs) |  (km s-1) |  |  |  |
BD+75 348 | 4840 | 2.00 | 1.43 |  $-$0.41$\pm$ 0.20 |  $-$0.42$\pm$ 0.18 |  $-$0.42 | 1
| 4700 | 1.80 | 2.00 |  $-$0.86$\pm$ 0.26 |  $-$0.88$\pm$ 0.02 |  $-$0.87 | 9
| 4900 | - | - | - | - | - | 8
| 4760 | - | - | - | - | - | 10
BD+09 3019 | 4220 | 2.10 | 2.37 |  $-$0.55$\pm$ 0.18 |  $-$0.54$\pm$ 0.11 |  $-$0.55 | 1
HD 238020 | 5150 | 2.10 | 1.36 |  $-$0.67$\pm$ 0.15 |  $-$0.68$\pm$ 0.16 |  $-$0.68 | 1
| 5035 | - | - | - | - | - | 8
HE 0319$-$0215 | 4650 | 0.50 | 1.33 |  $-$2.58$\pm 0.10$ |  $-$2.56$\pm 0.05$ |  $-$2.57 | 1
| 4416 | 0.64 | - | - | - |  $-$2.42 | 2
| - | - | - | - | - |  $-$2.30 | 3
| 4738 | 0.66 | 2.16 | - | - |  $-$2.90 | 4
HE 0507–1653 | 4970 | 2.20 | 1.48 |  $-$1.46$\pm 0.11$ |  $-$1.42$\pm 0.08$ |  $-$1.44 | 1
| 5000 | 2.40 | 2.00 |  $-$1.38$\pm 0.19$ |  $-$1.39$\pm 0.17$ |  $-$1.38 | 5
| - | - | - | - | - |  $-$1.42 | 6
| 4880 | 1.50 | - | - | - |  $-$1.81 | 2
| 4935 | 1.88 | - | - | - |  $-$1.32 | 7
| 5035 | 2.39 | 1.53 | - | - |  $-$1.35 | 4
HE 0930$-$0018 | 4190 | 2.65 | 1.86 |  $-$1.39$\pm 0.11$ |  $-$1.39$\pm 0.09$ |  $-$1.39 | 1
HE 1023–1504 | 4440 | 0.50 | 1.67 |  $-$1.66$\pm 0.14$ |  $-$1.66$\pm 0.07$ |  $-$1.66 | 1
| 4421 | 0.66 | - | - | - |  $-$2.50 | 2

References: 1. Our work, 2. Kennedy et al. (2011). 3. Hansen et al. (2016b),
4. Karinkuzhi et al. (2021), 5. Aoki et al. (2007), 6. Schuler et al. (2008),
7. Yong et al. (2013), 8. McDonald et al. (2012), 9. Začs et al. (2000), 10.
Bergeat et al. (2001)

##  6 Results

###  6.1 Abundance analysis

We have determined the elemental abundances of the program stars by using an
updated version of the code MOOG that assumes LTE conditions. We have
interpolated the model atmospheres to our derived stellar parameters from the
Kurucz grid of model atmospheres, with no convecting overshooting, for the
program stars. We have determined the abundances of light elements C, N, O,
Na, Mg, Si, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, and neutron-capture
elements Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Sm, Eu, Dy and Hf for the program
stars, depending upon the availability of the useful atomic lines or molecular
bands of the elements. Abundances of C, N & O and the elements showing
hyperfine splitting such as Sc, V, Mn, Ba, La, and Eu are determined using
spectrum synthesis calculations. The abundances of the other elements are
derived with the help of the equivalent width method by measuring the
equivalent widths of clean and unblended spectral lines (Table 6) of the
elements using the SPLOT task in IRAF. The atomic line information is taken
from the Kurucz database of atomic line list. We have presented the abundance
results in Tables 8 & 9.

Table 6: Equivalent widths (in mÅ) of lines used for calculation of elemental
abundances.

Wavelength | Element |  Elow | log gf | BD+75 348 | BD+09 3019 | HD 238020 | HE 0319–0215 | HE 0507–1653 | HE 0930–0018 | HE 1023–1504
---|---|---|---|---|---|---|---|---|---|---
(Å) |  | (eV) |  |  |  |  |  |  |  |
5682.633 | Na I | 2.10 | –0.700 | 115.8 (6.25) | 172.5 (6.08) | 64.4 (5.62) | 22.4 (4.71) | 45.2 (5.19) | 112.1 (5.39) | 51.5 (5.06)
5688.205 |  | 2.10 | –0.450 | 140.3 (6.42) | 170.6 (5.81) | 87.1 (5.77) | 25.3 (4.53) | 58.7 (5.17) | 136.8 (5.43) | -
6154.23 |  | 2.10 | –1.560 | 59.1 (6.14) | - | 16.1 (5.50) | - | - | - | -
6160.75 |  | 2.10 | –1.260 | 88.1 (6.30) | - | 30.1 (5.55) | - | 19.7 (5.21) | - | -

The numbers in the parenthesis in columns 5 to 11 give the derived abundances
from the respective line.
Note: This table is available in its entirety online only. A portion is shown
here for guidance regarding its form and content.

Table 7: Absolute abundances (log $\epsilon$) derived from different lines
using spectral synthesis calculations. Hyperfine splitting contributions are
taken from the sources given in Column 10.

Wavelength | Element | BD+75 348 | BD+09 3019 | HD 238020 | HE 0319–0215 | HE 0507–1653 | HE 0930–0018 | HE 1023–1504 | Reference
---|---|---|---|---|---|---|---|---|---
(Å) |  |  |  |  |  |  |  |  |
4415.557 | Sc II | - | - | 2.65 | 0.55 | - | - | - |  1a
5031.021 |  | - | - | 2.50 | - | - | - | - |  1a
5526.790 |  | 2.85 | - | 2.47 | - | - | - | - |  1a
5641.001 |  | 2.72 | 3.15 | 2.30 | - | 1.75 | - | 1.55 |  1a
5657.896 |  | 2.62 | 3.15 | 2.60 | - | 1.71 | 1.65 | - |  1a
5667.149 |  | 2.65 | - | 2.30 | - | - | 1.50 | - |  1a
5727.652 | V I | 3.12 | 3.88 | 3.23 |  $<$ 1.60 | 2.80 | 2.66 | 2.53 |  2a
4754.042 | Mn I | 4.55 | 3.55 | 4.62 | 2.15 | 3.75 | - | 3.28 |  3a
4762.367 |  | 4.60 | - | 4.56 | - | - | 3.15 | - |  3a
4823.524 |  | 4.60 | - | 4.62 | - | - | - | - |  3a
5853.668 | Ba II | 3.47 | - | - | 1.37 | 2.70 | 1.55 | 2.60 | 4
6141.713 |  | 3.29 | - | 1.75 | 1.60 | 2.90 | 2.20 | - | 4
4921.776 | La II | 2.60 | 2.80 | 0.90 | 0.25 | 1.60 | 0.80 | 1.30 | 5
6437.640 | Eu II | - | - | - | - | 0.10 | - | - |  6a
6645.064 |  | 0.80 | 1.02 | - | –1.20 | 0.12 | - | –0.25 | 7

a \- linemake
References: 1\. Lawler et al. (2019), 2. Lawler et al. (2014), 3. Den Hartog
et al. (2011), 4. McWilliam (1998), 5. Jonsell et al. (2006), 6. Lawler et al.
(2001), 7. Worley et al. (2013).

####  6.1.1 C, N, O

The abundance of carbon is derived using three molecular bands of carbon,
namely CH band around 4310 Å and C2 bands near 5165 and 5635 Å. Figure 2 shows
the spectral synthesis of C2 molecular band around 5165 Å. Abundance of N is
estimated from the CN molecular band around 4215 Å, adopting the carbon
abundance derived using the C2 and CH molecular bands. Abundance of oxygen
could be determined only for HD 238020. We have used the [O I] 6300 Å
forbidden line for estimating the abundance of oxygen.

For the star HD 238020, the C2 molecular band at 5635 Å and the CN molecular
band are found to be too weak to be used for abundance estimation. In Figure 3
we have shown a comparison of the C2 band at 5635 Å for the stars BD+75 348,
BD+09 3019 and HD 238020 to demonstrate the absence of the band in HD 238020.
We could not use the CH molecular band in HE 0507–1653 and CN molecular band
in BD+09 3019 for abundance estimation as the bands are found to be saturated.
For HE 0930–0018 and HE 1023–1504, the CH and the CN molecular bands could not
be used for abundance determination due to the low S/N (signal to noise ratio)
in the particular region of the spectra (Figure 4). BD+09 3019, HE 0319–0215,
HE 0507–1653, HE 0930–0018, and HE 1023–1504 are found to be carbon enhanced
with [C/Fe] $>$ 0.70. While BD+75 348 is mildly enhanced in carbon, abundance
of carbon in HD 238020 is found to be solar. Nitrogen is enhanced with [N/Fe]
$>$ 0.70 in all the three stars (BD+75 348, HE 0319–0215, HE 0507–1653), for
which abundance of nitrogen could be estimated. The wavelengths, lower
excitation potentials, and log $gf$ values of different molecular transitions
for the C2 bands at 5165 Å & 5635 Å and CN bands are adopted from Brooke et
al. (2013), Ram et al. (2014), and Sneden et al. (2014). The molecular
linelist for CH band at 4310 Å used for our calculation using
linemake666linemake contains laboratory atomic data (transition probabilities,
hyperfine and isotopic substructures) published by the Wisconsin Atomic
Physics and the Old Dominion Molecular Physics groups. These lists and
accompanying line list assembly software have been developed by C. Sneden and
are curated by V. Placco at https://github.com/vmplacco/linemake. (Placco et
al., 2021) are from Masseron et al. (2014). The abundances of carbon derived
from the different bands of C2 and CH are found to be quite similar with the
maximum difference of 0.16 dex for the star BD+09 3019. As shown in Goswami et
al. (2021), the change in abundance of C derived from C2 and CH bands varies
in the $\pm$0.04 dex range with the change in temperature in the range
$\pm$100 K. We observed negligible change in the abundance of C by varying log
$g$ and $\xi$ by $\pm$0.2 (cgs) and $\pm$0.2 kms-1 respectively. While CH band
shows a variation in the abundance of C by $\pm$0.04 dex with the metallicity
variation in the range $\pm$0.2 dex, the C2 bands show no variation.

Figure 2:  The spectral synthesis plot of C2 band around 5165 Å. The dotted
lines indicate the synthesized spectra and the solid lines indicate the
observed spectra. Two alternative synthetic spectra are shown corresponding to
$\Delta$[C/Fe] = +0.3 (long-dashed line) and $\Delta$[C/Fe] = $-$0.3 (short-
dashed line)  Figure 3:  Sample spectra of the C2 band at 5635 Å of the three
Ba stars. This band is not present in the star HD 238020.

Figure 4:  Sample spectra of HE 0930–0018 and HE 1023–1504 in the wavelength
regions 4205 – 4218 Å and 4300 – 4318 Å.

####  6.1.2 Na, Mg, Si, Ca, Sc, Ti, V

Abundance of Na in the program stars ranges from [Na/Fe] = 0.05 to 0.95 dex,
with the minimum [Na/Fe] for HD 238020 and the maximum for HE 0319–0215. Mg is
moderately enhanced in all the program stars except for BD+09 3019, for which
[Mg/Fe] = 1.26. We could estimate the abundance of Si only for HD 238020 using
a single line Si I 6237.32 Å, and found to be sub-solar with [Si/Fe] = –0.52.
This is somewhat surprising, as this object is classified as a mild Ba star
with a probability of being a thin disk object (see section 6.2 on Kinematic
analysis), and, in the case of thin/thick disk stars $\alpha$-elements
([$\alpha$/Fe]), are known to lie between 0.2 dex to 0.3 dex for stars with
–1.0 $<$ [Fe/H] $<$ 0 (Edvardsson et al., 1993). Within the metallicity range
–1.0 $<$ [Fe/H] $<$ 0, in barium stars [Si/Fe] is found to be in the range 0.0
dex to 0.58 dex (de Castro et al., 2016). Massive stars $>$ 10 M⊙ produce
$\alpha$-elements during hydrostatic oxygen burning and also during type II
supernovae explosions (Woosley & Weaver, 1986); hence Si is also expected to
show similar trend as seen in other $\alpha$-elements. Si is also known to
show high scatter at all metallicities –4 $<$ [Fe/H] $<$ 0\. However, in
metal-poor Red Horizontal Branch stars (i.e., BPS CS 22186–0005 ), [Si/Fe] is
found to be as low as $-$0.25 dex (Preston et al., 2006), 0.27 dex higher than
that observed in HD 238020. It will be worthwhile to investigate in future the
anomalous low Si abundance observed in HD 238020 that now remains unexplained.
Ca is found to range from sub-solar to super-solar abundances with –0.14 $<$
[Ca/Fe] $<$ 0.83. Abundance of Sc is estimated using spectrum synthesis
calculations of several Sc II lines (Table 7) whenever available. For five out
of the seven objects, we have derived the abundance of Ti from the spectral
lines of both the neutral (Ti I) and ionized (Ti II) species of Ti. The
abundances of Ti derived from both the species are found to be very close for
all the stars except for HE 0319–0215, with a difference of 0.14 dex. For
BD+09 3019 & HE 1023–1504 abundance of Ti could be derived only from Ti I
lines as Ti II lines are found to be severely blended. Abundance of V is
estimated from spectrum synthesis calculation of V I line at 5727.652 Å (Table
7). We could only estimate an upper limit of V for the object HE 0319–0215.
Abundance of V ranges from sub-solar to super-solar with –0.39 $<$ [V/Fe] $<$
0.50.

####  6.1.3 Cr, Mn, Co, Ni, Cu, Zn

For HD 238020, we could estimate the abundance of Cr from both neutral (Cr I)
and ionized species (Cr II) of Cr. In other stars, we could not detect the
lines due to Cr II, and abundance could be derived only from Cr I lines. In
the program stars, abundance of Cr ranges from –0.51 dex to 0.11 dex. We have
derived the abundance of Mn using spectrum synthesis calculation of several
lines due to Mn I (Table 7). Mn is found to be sub-solar in the program stars
with –1.33 $<$ [Mn/Fe] $<$ –0.15. For barium stars in the metallicity range –1
$<$ [Fe/H] $<$ 0.0 , [Mn/Fe] is found to lie in the range –0.55 dex to +0.37
dex (Yang et al., 2016; Shejeelammal et al., 2020). In our sample, the
spectrum synthesis of Mn I 4754.042 Å line in BD+09 3019, a strong barium star
returned a value [Mn/Fe] = –1.33, making it the most Mn deficient barium star.
A few extremely metal-poor stars are however known to exhibit such low Mn
abundance (i.e, HE 1012–1540 (–1.00 dex), HE 1356–0622 (–0.98 dex) (Cohen et
al., 2008)). Lines due to Co, Cu & Zn are not usable for abundance
determination in HE 0319–0215. A few samples of these lines of this star are
shown in Figure 15. For HE 1023–1504, we could not estimate the abundance of
Cu due to the unavailability of good lines. In the other program stars Co
ranges from sub-solar to solar abundances with –0.21 $<$ [Co/Fe] $<$ 0.14, Ni
ranges from sub-solar to super-solar abundances with –0.30 $<$ [Ni/Fe] $<$
0.70, [Cu/Fe] ranges from –0.20 dex to 0.38 dex and [Zn/Fe] ranges from –0.16
$<$ [Zn/Fe] $<$ 0.13.

####  6.1.4 Sr, Y, Zr

We could derive the abundance of Sr for all the stars except HE 1023–1504. Sr
II 4215.52 Å line appears in the region of the CN molecular band around 4215
Å. That is why, it is not always possible to use this particular line for the
objects with enhanced C and N abundances. We have used this line to estimate
the abundance of Sr for HD 238020. For the stars BD+75 348, HE 0319–0215, HE
0507–1653 and HE 0930–0018 Sr I 4607.33 Å line (Table 7) is used for spectrum
synthesis calculations. The abundance of Sr ([Sr/Fe]) in the program stars
ranges from 0.08 dex to 1.67 dex. Y is found to be enhanced ([Y/Fe] $>$ 0.70)
in all the program stars except HD 238020 (with [Y/Fe] = –0.26). For BD+75
348, HD 238020 and HE 0507–1653 we could estimate the abundance of Zr from the
lines due to both neutral (Zr I) and ionized (Zr II) species. The abundance of
Zr derived from the lines of both the species is closely similar, with the
largest difference of 0.25 dex for BD+75 348. Abundance of Zr ranges from 0.05
dex to 1.63 dex in the program stars.

####  6.1.5 Ba, La, Ce, Pr, Nd, Sm, Eu, Dy, Hf

Abundances of the neutron-capture elements are enhanced in all the program
stars except HD 238020. Abundances of Eu and Hf could not be estimated for HD
238020 as no lines could be detected. Abundances of Ba through Dy in HD 238020
are found to be moderately enhanced with 0.11 $<$ [X/Fe] $<$ 0.48.

Abundance of Ba is derived using spectral synthesis calculations of Ba II
5853.668 Å amd 6141.713 Å lines (Table 7) whenever available. Abundance of Ba
could not be derived for BD+09 3019 as the Ba lines are found to be too strong
and saturated. In the program stars, [Ba/Fe] ranges from 1.09 dex to 2.08 dex.
Abundance of La is derived using spectrum synthesis calculation of La II
4921.776 Å line (Table 7). La is found to be enhanced in the program stars
with 1.09 $<$ [La/Fe] $<$ 2.25. [Ce/Fe] ranges from 1.34 dex to 2.50 dex in
the program stars. Abundances of Pr, Nd and Sm are enhanced ([X/Fe] $>$ 0.90)
in the program stars. Abundance of Eu is derived using spectrum synthesis
calculations of Eu II 6437.640 Å & 6645.064 Å (Table 7). Abundance of Eu could
not be derived for HE 0930–0018 as no Eu lines could be found in the spectrum
(Figure 16). Eu is found to be enhanced ([Eu/Fe] $>$ 0.70) in the rest of the
program stars with 0.70 $<$ [Eu/Fe] $<$ 1.05. Abundance of Dy could be derived
only for BD+75 348, BD+09 3019 and HD 238020 and abundance of Hf could only be
derived for BD+75 348.

Table 8: Elemental abundances in BD+75 348, BD+09 3019 and HD 238020

| BD+75 348 | BD+09 3019 | HD 238020
---|---|---|---
Element | Z |  solar $log{\epsilon}^{a}$ | $log{\epsilon}$ | [X/H] | [X/Fe] | $log{\epsilon}$ | [X/H] | [X/Fe] | $log{\epsilon}$ | [X/H] | [X/Fe]
|  |  | (dex) |  |  | (dex) |  |  | (dex) |  |
C (C2, 5165 Å) | 6 | 8.43 | 8.35 (syn) |  $-$0.08 | 0.34 | 8.70 (syn) | 0.27 | 0.82 | 7.75 (syn) |  $-$0.68 | 0.00
C (C2, 5635 Å) | 6 | 8.43 | 8.30 (syn) |  $-$0.13 | 0.29 | 8.71 (syn) | 0.28 | 0.83 | - | - | -
C (CH, 4310 Å) | 6 | 8.43 | 8.30 (syn) |  $-$0.13 | 0.29 | 8.55 (syn) | 0.12 | 0.67 | 7.68 (syn) |  $-$0.75 |  $-$0.07
N (CN, 4215 Å) | 7 | 7.83 | 8.20 (syn) | 0.37 | 0.79 | (saturated) | - | - | - | - | -
O i | 8 | 8.69 | - | - | - | - | - | - | 8.09 (syn) |  $-$0.60 | 0.08
Na i | 11 | 6.24 |  6.28$\pm$0.12 (4) | 0.04 | 0.46 |  5.95$\pm$0.20 (2) |  $-$0.29 | 0.26 |  5.61$\pm$0.11 (4) |  $-$0.63 | 0.05
Mg i | 12 | 7.60 |  7.38$\pm$0.17 (4) |  $-$0.22 | 0.20 | 8.31 (1) | 0.71 | 1.26 |  7.29$\pm$0.08 (4) |  $-$0.31 | 0.37
Si i | 14 | 7.51 | - | - | - | - | - | - | 6.31 (1) |  $-$1.20 |  $-$0.52
Ca i | 20 | 6.34 |  5.97$\pm$0.21 (16) |  $-$0.37 | 0.05 |  5.65$\pm$0.00 (2) |  $-$0.69 |  $-$0.14 |  5.83$\pm$0.19 (21) |  $-$0.51 | 0.17
Sc ii∗ | 21 | 3.15 |  2.71$\pm$0.09 (4) |  $-$0.44 |  $-$0.02 |  3.15$\pm$0.00 (2) | 0.00 | 0.55 |  2.47$\pm$0.13 (6) |  $-$0.68 | 0.00
Ti i | 22 | 4.95 |  4.65$\pm$0.20 (13) |  $-$0.30 | 0.12 |  4.78$\pm$0.19 (2) |  $-$0.17 | 0.38 |  4.45$\pm$0.11 (14) |  $-$0.50 | 0.18
Ti ii | 22 | 4.95 |  4.65$\pm$0.19 (10) |  $-$0.30 | 0.12 | - | - | - |  4.40$\pm$0.20 (22) |  $-$0.55 | 0.13
V i∗ | 23 | 3.93 | 3.12 (1) |  $-$0.81 |  $-$0.39 | 3.88 (1) |  $-$0.05 | 0.50 | 3.23 (1) |  $-$0.70 |  $-$0.02
Cr i | 24 | 5.64 |  5.23$\pm$0.15 (7) |  $-$0.41 | 0.01 |  4.85$\pm$0.18 (3) | –0.79 | –0.24 |  4.98$\pm$0.12 (13) |  $-$0.66 | 0.02
Cr ii | 24 | 5.64 | - | - | - | - | - | - | 5.01 (1) |  $-$0.63 | 0.05
Mn i∗ | 25 | 5.43 |  4.58$\pm$0.02 (3) |  $-$0.85 |  $-$0.43 | 3.55 (1) | –1.88 | –1.33 |  4.60$\pm$0.03 (3) |  $-$0.83 |  $-$0.15
Fe i | 26 | 7.50 |  7.09$\pm$0.20 (85) |  $-$0.41 | - |  6.95$\pm$0.18 (36) |  $-$0.55 | - |  6.83$\pm$0.15 (136) |  $-$0.67 | -
Fe ii | 26 | 7.50 |  7.08$\pm$0.18 (12) |  $-$0.42 | - |  6.96$\pm$0.11 (3) |  $-$0.54 | - |  6.82$\pm$0.16 (17) |  $-$0.68 | -
Co i | 27 | 4.99 |  4.49$\pm$0.10 (2) |  $-$0.50 |  $-$0.08 | 4.23 (1) | –0.76 | –0.21 |  4.30$\pm$0.20 (4) |  $-$0.69 |  $-$0.01
Ni i | 28 | 6.22 |  5.77$\pm$0.24 (12) |  $-$0.45 |  $-$0.03 | 5.65 (1) | –0.57 | –0.02 |  5.60$\pm$0.21 (15) |  $-$0.62 | 0.06
Cu i | 29 | 4.19 | 3.66 (1) |  $-$0.53 |  $-$0.11 | 3.62 (1) | –0.57 | –0.02 | 3.89 (1) |  $-$0.30 | 0.38
Zn i | 30 | 4.56 | 4.12 (1) |  $-$0.44 |  $-$0.02 | 3.87 (1) | –0.69 | –0.14 |  3.75$\pm$0.04 (2) |  $-$0.81 |  $-$0.13
Sr i | 38 | 2.87 | 3.40 (syn) | 0.53 | 0.95 | 3.99 (1) | 1.12 | 1.67 | - | - | -
Sr ii | 38 | 2.87 | - | - | - | - | - | - | 2.27 (1) |  $-$0.60 | 0.08
Y ii | 39 | 2.21 |  3.06$\pm$0.16 (10) | 0.85 | 1.27 |  3.52$\pm$0.20 (2) | 1.31 | 1.86 |  1.27$\pm$0.12 (8) |  $-$0.94 |  $-$0.26
Zr i | 40 | 2.58 |  3.16$\pm$0.08 (3) | 0.58 | 1.00 |  2.98$\pm$0.14 (3) | 0.40 | 0.95 |  2.01$\pm$0.06 (2) |  $-$0.57 | 0.11
Zr ii | 40 | 2.58 |  3.41$\pm$0.09 (3) | 0.83 | 1.25 | - | - | - |  1.95$\pm$0.04 (2) |  $-$0.63 | 0.05
Ba ii∗ | 56 | 2.18 |  3.38$\pm$0.13 (2) | 1.20 | 1.62 | - | - | - | 1.75 (1) |  $-$0.43 | 0.25
La ii∗ | 57 | 1.10 | 2.60 (1) | 1.50 | 1.92 | 2.80 (1) | 1.70 | 2.25 | 0.90 (1) |  $-$0.20 | 0.48
Ce ii | 58 | 1.58 |  2.97$\pm$0.20 (13) | 1.39 | 1.81 |  3.07$\pm$0.16 (3) | 1.49 | 2.04 |  1.09$\pm$0.11 (7) |  $-$0.49 | 0.19
Pr ii | 59 | 0.72 |  2.17$\pm$0.22 (5) | 1.45 | 1.87 |  2.65$\pm$0.15 (3) | 1.93 | 2.48 |  0.50$\pm$0.20 (2) |  $-$0.22 | 0.46
Nd ii | 60 | 1.42 |  2.63$\pm$0.18 (11) | 1.21 | 1.63 |  2.81$\pm$0.06 (2) | 1.39 | 1.94 |  1.00$\pm$0.25 (12) |  $-$0.42 | 0.26
Sm ii | 62 | 0.96 |  2.08$\pm$0.07 (3) | 1.12 | 1.54 |  2.78$\pm$0.16 (3) | 1.82 | 2.37 |  0.70$\pm$0.07 (4) |  $-$0.26 | 0.42
Eu ii∗ | 63 | 0.52 | 0.80 (1) | 0.28 | 0.70 | 1.02 (1) | 0.50 | 1.05 | - | - | -
Dy ii | 66 | 1.10 | 1.49 (1) | 0.39 | 0.81 | 2.43 (1) | 1.33 | 1.88 | 0.53 (1) |  $-$0.57 | 0.11
Hf ii | 72 | 0.85 | 2.33 (1) | 1.48 | 1.90 | - | - | - | - | - | -

∗ abundance is derived using spectrum synthesis calculations. a Asplund et al.
(2009), Columns 4, 7 & 10 present the abundances ($log{\epsilon}$) of the
different elements along with the standard deviations (when more than one line
is used to derive the abundance). The number inside the parenthesis in columns
4, 7 & 10 shows the number of lines used for the abundance determination.

Table 9: Elemental abundances in HE 0319–0215, HE 0507–1653, HE 0930–0018 and
HE 1023–1504

| HE 0319–0215 | HE 0507–1653 | HE 0930–0018 | HE 1023–1504
---|---|---|---|---
Element | Z |  solar $log{\epsilon}^{a}$ | $log{\epsilon}$ | [X/H] | [X/Fe] | $log{\epsilon}$ | [X/H] | [X/Fe] | $log{\epsilon}$ | [X/H] | [X/Fe] | $log{\epsilon}$ | [X/H] | [X/Fe]
|  |  | (dex) |  |  | (dex) |  |  | (dex) |  |  | (dex) |  |
C (C2, 5165 Å) | 6 | 8.43 | 8.23 (syn) |  $-$0.20 | 2.37 | 8.18 (syn) |  $-$0.25 | 1.19 | 8.67 (syn) | 0.24 | 1.63 | 8.65 (syn) | 0.22 | 1.88
C (C2, 5635 Å) | 6 | 8.43 | 8.29 (syn) |  $-$0.14 | 2.43 | 8.12 (syn) |  $-$0.31 | 1.13 | 8.70 (syn) | 0.27 | 1.66 | 8.72 (syn) | 0.29 | 1.95
C (CH, 4310 Å) | 6 | 8.43 | 8.30 (syn) |  $-$0.13 | 2.44 | (saturated) | - | - | Low S/N | - | - | Low S/N | - | -
N (CN, 4215 Å) | 7 | 7.83 | 7.33 (syn) |  $-$0.50 | 2.07 | 7.80 |  $-$0.03 | 1.41 | Low S/N | - | - | Low S/N | - | -
Na i | 11 | 6.24 |  4.62$\pm$0.12 (2) |  $-$1.62 | 0.95 |  5.19$\pm$0.02 (3) |  $-$1.05 | 0.39 |  5.41$\pm$0.03 (2) |  $-$0.83 | 0.56 | 5.06 (1) |  $-$1.18 | 0.48
Mg i | 12 | 7.60 | 5.51 (1) |  $-$2.09 | 0.48 |  6.68$\pm$0.11 (3) |  $-$0.92 | 0.52 | 6.69 (1) |  $-$0.91 | 0.48 |  6.30$\pm$0.05 (syn, 2) | –1.30 | 0.36
Ca i | 20 | 6.34 |  4.49$\pm$0.21 (4) |  $-$1.85 | 0.72 |  5.30$\pm$0.19 (8) |  $-$1.04 | 0.40 |  5.34$\pm$0.11 (6) |  $-$1.00 | 0.39 |  5.51$\pm$0.14 (3) |  $-$0.83 | 0.83
Sc ii∗ | 21 | 3.15 | 0.55 (1) |  $-$2.60 |  $-$0.03 |  1.73$\pm$0.03 (2) |  $-$1.42 | 0.02 |  1.58$\pm$0.08 (2) |  $-$1.57 |  $-$0.18 | 1.55 (1) |  $-$1.60 | 0.06
Ti i | 22 | 4.95 | 3.16 (1) |  $-$1.79 | 0.78 |  3.88$\pm$0.11 (3) |  $-$1.07 | 0.37 |  3.46$\pm$0.21 (7) |  $-$1.49 |  $-$0.10 |  3.95$\pm$0.15 (3) |  $-$1.00 | 0.66
Ti ii | 22 | 4.95 |  3.30$\pm$0.12 (3) |  $-$1.65 | 0.92 |  3.85$\pm$0.23 (8) |  $-$1.10 | 0.34 |  3.45$\pm$0.20 (4) |  $-$1.50 |  $-$0.11 | - | - | -
V i∗ | 23 | 3.93 |  $<$ 1.60 (1) |  $<$ $-$2.33 |  $<$ 0.24 | 2.80 (1) |  $-$1.13 | 0.31 | 2.66 (1) |  $-$1.27 | 0.12 | 2.53 (1) |  $-$1.40 | 0.26
Cr i | 24 | 5.64 |  3.18$\pm$0.19 (3) |  $-$2.46 | 0.11 |  4.21$\pm$0.15 (6) |  $-$1.43 | 0.01 |  3.74$\pm$0.16 (3) |  $-$1.90 |  $-$0.51 |  3.98$\pm$0.11 (2) |  $-$1.66 | 0.00
Mn i∗ | 25 | 5.43 | 2.15 (1) |  $-$3.28 |  $-$0.71 | 3.75 (1) |  $-$1.68 |  $-$0.24 | 3.15 (1) |  $-$2.28 |  $-$0.89 | 3.28 (1) |  $-$2.15 |  $-$0.49
Fe i | 26 | 7.50 |  4.92$\pm$0.10 (30) |  $-$2.58 | - |  6.04$\pm$0.11 (36) |  $-$1.46 | - |  6.11$\pm$0.11 (19) |  $-$1.39 | - |  5.84$\pm$0.14 (20) |  $-$1.66 | -
Fe ii | 26 | 7.50 |  4.94$\pm$0.05 (5) |  $-$2.56 | - |  6.08$\pm$0.08 (4) |  $-$1.42 | - |  6.11$\pm$0.09 (3) |  $-$1.39 | - |  5.84$\pm$0.07 (2) |  $-$1.66 | -
Co i | 27 | 4.99 | - | - | - | 3.52 (1) |  $-$1.47 |  $-$0.03 |  3.49$\pm$0.12 (2) |  $-$1.50 |  $-$0.11 | 3.47 (1) |  $-$1.52 | 0.14
Ni i | 28 | 6.22 |  3.35$\pm$0.05 (syn, 2) |  $-$2.87 |  $-$0.30 |  4.76$\pm$0.18 (4) |  $-$1.46 |  $-$0.02 |  5.57$\pm$0.16 (3) |  $-$0.65 | 0.74 |  5.26$\pm$0.18 (2) |  $-$0.96 | 0.70
Cu i | 29 | 4.19 | - | - | - | 2.55 (1) |  $-$1.64 |  $-$0.20 | 2.85 (1) |  $-$1.34 | 0.05 | - | - | -
Zn i | 30 | 4.56 | - | - | - | 3.21 (1) |  $-$1.35 | 0.09 | 3.30 (1) |  $-$1.26 | 0.13 | 2.74 (1) |  $-$1.82 |  $-$0.16
Sr i | 38 | 2.87 | 1.97 (syn) |  $-$0.90 | 1.67 | 2.97 (syn) | 0.10 | 1.54 | 2.37 (syn) |  $-$0.50 | 0.89 | - | - | -
Y ii | 39 | 2.21 |  0.79$\pm$0.20 (2) |  $-$1.42 | 1.15 |  1.97$\pm$0.11 (6) |  $-$0.24 | 1.20 |  1.52$\pm$0.18 (3) |  $-$0.69 | 0.70 |  1.67$\pm$0.21 (2) |  $-$0.54 | 1.12
Zr i | 40 | 2.58 | - | - | - |  2.71$\pm$0.09 (2) | 0.13 | 1.57 | 1.57 (1) |  $-$1.01 | 0.38 | - | - | -
Zr ii | 40 | 2.58 | 0.63 (1) |  $-$1.95 | 0.62 |  2.77$\pm$0.21 (2) | 0.19 | 1.63 | - | - | - | 2.23 (1) |  $-$0.35 | 1.31
Ba ii∗ | 56 | 2.18 |  1.49 $\pm$0.12 (2) |  $-$0.69 | 1.88 |  2.80 $\pm$0.10 (2) | 0.62 | 2.06 |  1.88 $\pm$0.32 (2) |  $-$0.30 | 1.09 | 2.60 (1) | 0.42 | 2.08
La ii∗ | 57 | 1.10 | 0.25 (1) | –0.85 | 1.72 | 1.60 (1) | 0.50 | 1.94 | 0.80 (1) |  $-$0.30 | 1.09 | 1.30 (1) | 0.20 | 1.86
Ce ii | 58 | 1.58 |  0.93$\pm$0.02 (2) |  $-$0.65 | 1.92 |  2.17$\pm$0.09 (9) | 0.59 | 2.03 |  1.53$\pm$0.13 (3) |  $-$0.05 | 1.34 |  2.42$\pm$0.19 (3) | 0.84 | 2.50
Pr ii | 59 | 0.72 | 0.03 (1) |  $-$0.69 | 1.88 | 1.25 (1) | 0.53 | 1.97 |  0.41$\pm$0.09 (2) |  $-$0.31 | 1.08 |  1.60$\pm$0.11 (3) | 0.88 | 2.54
Nd ii | 60 | 1.42 |  0.74$\pm$0.22 (6) |  $-$0.68 | 1.89 |  2.01$\pm$0.15 (11) | 0.59 | 2.03 |  0.96$\pm$0.14 (8) |  $-$0.46 | 0.93 |  1.91$\pm$0.13 (5) | 0.49 | 2.15
Sm ii | 62 | 0.96 |  0.19$\pm$0.13 (4) |  $-$0.77 | 1.80 |  1.60$\pm$0.15 (4) | 0.64 | 2.08 |  0.55$\pm$0.20 (2) |  $-$0.41 | 0.98 |  1.24$\pm$0.14 (2) | 0.28 | 1.94
Eu ii∗ | 63 | 0.52 |  $-$1.20 (1) |  $-$1.72 | 0.85 |  0.11 $\pm$0.01 (2) |  $-$0.41 | 1.03 | - | - | - |  $-$0.25 (1) |  $-$0.77 | 0.89

∗ abundance is derived using spectrum synthesis calculations. a Asplund et al.
(2009), Columns 4, 7, 10 & 13 present the abundances ($log{\epsilon}$) of the
different elements along with the standard deviations (when more than one line
is used to derive the abundance). The number inside the parenthesis in columns
4, 7, 10 & 13 shows the number of lines used for the abundance determination.

###  6.2 Kinematic analysis of the program stars

We have carried out the kinematic analysis of the program stars, following the
procedure described in Purandardas et al. (2019) and Goswami et al. (2021), to
know the Galactic population to which the program stars belong. The values of
parallax ($\pi$) and proper motions ($\mu_{\alpha}$, $\mu_{\delta}$) are taken
from the Gaia database and radial velocities of our estimates are considered
for calculating the components of space velocity (ULSR, VLSR, WLSR) with
respect to Local Standard of Rest (LSR). The total space velocity (Vspa) is
given by Vspa = $\sqrt{U_{LSR}^{2}+V_{LSR}^{2}+W_{LSR}^{2}}$. We have
calculated the probabilities of the program stars being in the halo, thin or
thick disc using the procedures given by Reddy et al. (2006), Bensby et al.
(2003, 2004), and Mishenina et al. (2004). For the probability determination,
it is assumed that Gaussian distribution functions for ULSR, VLSR and WLSR,
with given mean values and dispersions represent thin disc, thick disc and
halo populations (Reddy et al., 2006). A detailed discussion of the procedure
can be found in our previous works (Purandardas et al., 2019; Goswami et al.,
2021). The values of ULSR, VLSR, WLSR, Vspa and the probability estimates for
the objects being members of the thin disc (Pthin), thick disc (Pthick) and
halo (Phalo) population are presented in Table LABEL:tab:kinematicresults.
BD+75 348, HD 238020 and HE 0930–0018 show the probability of being thin disc
objects, BD+09 3019 is a thick disc object and HE 0319–0215 & HE 0507–1653 are
halo objects. A toomre diagram is shown in Figure 5.

Table 10: Spatial velocity and probability estimates Star Name | $U_{LSR}(km/s)$ | $V_{LSR}(km/s)$ | $W_{LSR}(km/s)$ | $V_{spa}(km/s)$ | $P_{thin}$ | $P_{thick}$ | $P_{halo}$
---|---|---|---|---|---|---|---
BD+75 348 | –44.75 $\pm 1.17$ | 43.21 $\pm 0.93$ | 17.28 $\pm 1.07$ | 64.56 $\pm 0.10$ | 0.97 | 0.03 | 0.00
BD+09 3019 | 102.34 $\pm 4.47$ |  $-$80.69 $\pm 4.10$ |  $-$60.85 $\pm 3.04$ | 143.83 $\pm 0.41$ | 0.00 | 0.97 | 0.03
HD 238020 | –43.06 $\pm 1.41$ |  $-$13.73 $\pm 1.02$ |  $-$39.08 $\pm 2.60$ | 59.75 $\pm 2.95$ | 0.90 | 0.10 | 0.00
HE 0319$-$0215 | 305.94 $\pm 22.00$ | –321.86 $\pm 65.35$ | 107.59 $\pm 16.06$ | 456.91 $\pm 27.24$ | 0.00 | 0.00 | 1.00
HE 0507$-$1653 | –247.94 $\pm 1.03$ | –225.22 $\pm 2.55$ |  $-$85.75 $\pm 3.89$ | 345.76 $\pm 3.39$ | 0.00 | 0.00 | 1.00
HE 0930$-$0018 | –53.49 $\pm 0.42$ | –0.63 $\pm 0.47$ | 18.80 $\pm 0.40$ | 56.70 $\pm 0.27$ | 0.98 | 0.02 | 0.00
Figure 5:  Toomre diagram. Red filled squares represent the CEMP-s stars and
blue filled circles represent Ba stars. The dashed curves connect the loci
with same VLSR.

##  7 Discussion

###  7.1 Classification schemes of the mild/strong Ba and CEMP-s stars

####  7.1.1 Ba stars

After the first identification of Ba stars by Bidelman & Keenan (1951),
several authors (Pilachowski, 1977; Sneden et al., 1981; Lu, 1991; Jorissen et
al., 1998; Yang et al., 2016; de Castro et al., 2016; Escorza et al., 2017;
Jorissen et al., 2019) have put forward classification criteria to distinguish
the mild and strong Ba stars. Pilachowski (1977) reported abundance analysis
of seven mild Ba stars and demonstrated that they show [s/Fe] $\geq$ 0.50,
where [s/Fe] implies the average abundance of the available s-process
elements. Sneden et al. (1981) pointed out that limiting values of [s/Fe] for
mild Ba stars and classical (strong) Ba stars are 0.21 and 0.73 respectively.
Using the Ba index given by Warner (1965), Lu (1991) classified the Ba stars
with Ba indices 0.3 – 1.5 and 2 – 5 as mild and strong Ba stars, respectively.
Jorissen et al. (1998) classified the stars with Ba $\leq$ 2 as mild and Ba =
3 – 5 as strong Ba stars. Escorza et al. (2017) considered stars with Ba
indices 1 and 2 as mild Ba stars and 3 – 5 as strong Ba stars. However,
avoiding the use of Ba indices, Yang et al. (2016) used [Ba/Fe] as an
indicator to distinguish the two groups. They considered stars showing [Ba/Fe]
$>$ 0.60 as strong Ba stars. Their sample stars show 0.17 $<$ [Ba/Fe] $<$ 0.54
for mild Ba stars. de Castro et al. (2016) used [s/Fe] $\geq$ 0.25 as a
distinguishing value between normal giants and Ba stars. Jorissen et al.
(2019) recommended that [La/Fe] and [Ce/Fe] for strong Ba stars are greater
than equal to unity, and mild Ba stars always show [Ce/Fe] $\geq$ 0.2.

In this study, we use a similar criteria as that of Yang et al. (2016). But,
as abundance of Ba is not reported for many Ba stars in the literature due to
the saturation of strong Ba lines in the spectra of Ba stars, we use [hs/Fe]
to differentiate the mild and strong Ba stars. Here, hs (heavy-s) represents
Ba, La, Ce and Nd. We have not used Pr and Sm in the calculations of hs, as
r-process contributes more to these two elements than that of s-process. In
order to reduce the systematic error in calculating [hs/Fe], we have
considered only those stars for which abundances of at least two or more
heavy-s process elements are reported in the literature. We consider stars
with [hs/Fe] $>$ 0.60 as strong Ba stars and stars with 0.17 $<$ [hs/Fe] $<$
0.60 as mild Ba stars. We have discarded the possibility of using [s/Fe] as a
classifier, because [s/Fe] contains not only Pr and Sm, but also the ls
elements Sr, Y, and Zr, and the s-process AGB models cannot reproduce the ls
elements satisfactorily. These elements are believed to have contributions
from several different sources.

####  7.1.2 CEMP-s stars

CEMP stars are metal-poor stars ([Fe/H] $<$ –1.0) with [C/Fe] $>$ 0.7. Several
classification schemes have been proposed in the literature (Beers &
Christlieb, 2005; Jonsell et al., 2006; Masseron et al., 2010; Abate et al.,
2016; Frebel, 2018; Hansen et al., 2019; Goswami et al., 2021) to identify the
CEMP-s stars from the different subclasses of CEMP stars. However, it is
difficult to distinguish the CEMP-s and CEMP-r/s stars (see Goswami et al.
(2021) for more details). Beers & Christlieb (2005), for the first time used
[Ba/Fe], [Eu/Fe] and [Ba/Eu] to differentiate between the CEMP stars.
Following it, Jonsell et al. (2006), Masseron et al. (2010) and Abate et al.
(2016) used the same abundance ratios with different limiting values. Hansen
et al. (2019) used [Sr/Ba] to distinguish the subclasses. In this paper, we
have followed the classification scheme discussed in Goswami et al. (2021)\-

  * •

CEMP: [C/Fe]$\geq$0.7

  * •

CEMP-r/s: [Ba/Fe]$\geq$1.0, [Eu/Fe]$\geq$1.0

    * i)

0.0$\leq$[Ba/Eu]$\leq$1.0 and/or 0.0$\leq$[La/Eu]$\leq$0.7

  * •

CEMP-s: [Ba/Fe]$\geq$1.0

    * i.)

[Eu/Fe]$<$1.0, [Ba/Eu]$>$0.0 and/or [La/Eu]$>$0.5

    * ii.)

[Eu/Fe]$\geq$1.0, [Ba/Eu]$>$1.0 and/or [La/Eu]$>$0.7

###  7.2 Classification of the program stars

####  7.2.1 BD+75 348, BD+09 3019 & HD 238020

From the visual inspection of the strong lines Sr II 4077 Å and Ba II 4554 Å,
we classify these three objects as Ba stars. The [Fe/H] of BD+75 348, BD+09
3019 & HD 238020 lies between –0.68 and –0.42. BD+75 348, with [C/Fe] $\sim$
0.31, is not a carbon enhanced star, but it shows enhancement in neutron-
capture elements. BD+09 3019, with [C/Fe] $\sim$ 0.77, shows enhancement in
carbon, and the neutron-capture elements are also strongly enhanced in the
star. The high value of [hs/Fe] ($>$ 0.60) put BD+75 348 and BD+09 3019 in the
category of strong Ba stars. HD 238020, on the other hand, shows only mild
enhancement in neutron-capture elements with solar abundance of carbon. The
C/O of HD 238020 is greater than unity. With [hs/Fe] = 0.30, we classify this
object as a mild Ba star.

####  7.2.2 HE 0319–0215, HE 0507–1653, HE 0930–0018 & HE 1023–1504

HE 0319–0215, HE 0507–1653, HE 0930–0018 & HE 1023–1504 are metal-poor (MP:
[Fe/H] $<$ –1.0) and very metal-poor (VMP: [Fe/H] $<$ –2.0) stars with –1.39
$<$[Fe/H] $<$ –2.57. All these stars are carbon enhanced ([C/Fe] $>$ 1.0) and
enriched in neutron-capture elements. All four stars fall in the category of
CEMP-s stars following the classification criteria of Goswami et al. (2021).
Although [Eu/Fe] is greater than unity in HE 0507–1653 and the classification
scheme of Abate et al. (2016) (Figure 6) puts it in the category of CEMP-r/s
stars based on [Ba/Eu] $>$ 0.0. Figure 6 shows that this star is a CEMP-s star
from the classification scheme of Goswami et al. (2021). We tried to fit
i-process models (Hampel et al., 2016) calculated for neutron-densities, n
$\sim$ 109 – 1015 cm-3 to the observed abundance pattern of HE 0507–1653. We
found that the model with n = 109 cm-3 gives the minimum $\chi^{2}$ value. So,
this star cannot be a CEMP-r/s star. However, we will discuss in Section 7.4
that s-process yields produced by an M = 2.0 M⊙ AGB can satisfactorily
reproduce the observed abundance pattern of the star, placing it in the CEMP-s
category. This verifies the upper limit on [Ba/Eu] ($>$ 1.0) for CEMP-r/s
stars put forward by our previous work (Goswami et al., 2021). Classifications
of the program stars along with some important abundance ratios, such as
[ls/Fe], [hs/Fe], [hs/ls], [Eu/Fe], [Ba/Eu] & [La/Eu] are presented in Table
11.

Figure 6:  Filled red circles and filled black squares respectively represent
literature CEMP-r/s and CEMP-s stars compiled by Goswami et al. (2021), the
blue and the green stars represent the CEMP-s and Ba stars of this study.
panel a: The grid formed by the dotted red lines represents the region of
CEMP-r/s stars put forward by Beers & Christlieb (2005). The grid formed by
the dashed magenta lines represents the region of CEMP-r/s stars put forward
by Abate et al. (2016). panel b: Grid formed by the dotted red lines bound by
0.0 $<$ [La/Eu] $<$ 0.6 and 0.0 $<$ [Ba/Eu] $<$ 1.0 indicates the region
defined for CEMP-r/s stars by Goswami et al. (2021). The grid formed by the
black dashed lines bound by 0.5 $<$ [La/Eu] $<$ 0.7 represents the region
where [Eu/Fe] $>$ 1.0 classifies the stars as CEMP-r/s and [Eu/Fe] $<$ 1.0
classifies the stars as CEMP-s.  Table 11: Observed abundance ratios and
classifications of the program stars

Star Name | [Fe/H] | [ls/Fe] | [hs/Fe] | [hs/ls] | [Eu/Fe] | [Ba/Eu] | [La/Eu] | Classification
---|---|---|---|---|---|---|---|---
BD+75 348 | –0.42 | 1.16 | 1.75 | 0.59 | 0.70 | 0.92 | 1.22 | Strong Ba star
BD+09 3019 | –0.55 | 1.49 | 2.08 | 0.59 | 1.05 | - | 1.20 | Strong Ba star
HD 238020 | –0.68 | –0.04 | 0.30 | 0.34 | - | - | - | Mild Ba star
HE 0319–0215 | –2.57 | 1.15 | 1.85 | 0.70 | 0.85 | 1.03 | 0.87 | CEMP-s star
HE 0507–1653 | –1.44 | 1.46 | 2.02 | 0.56 | 1.03 | 1.03 | 0.91 | CEMP-s star
HE 0930–0018 | –1.39 | 0.66 | 1.11 | 0.45 | - | - | - | CEMP-s star
HE 1023–1504 | –1.66 | 1.22 | 2.15 | 0.93 | 0.89 | 1.19 | 0.97 | CEMP-s star

###  7.3 Masses of the program stars

The masses of the program stars are estimated from the position of the stars
on the HR diagram (log(L/L⊙) versus log(Teff) plot). In order to estimate the
luminosities (L) of the program stars using Equation 1 the visual magnitudes
(V) of the stars are taken from SIMBAD, the parallaxes ($\pi$) are taken from
Gaia777https://gea.esac.esa.int/archive/, the interstellar extinction (Av)
values are calculated from the formula given in Chen et al. (1998), the
bolometric corrections (BC) are calculated using the empirical calibrations of
Alonso et al. (1999).

$log(L/L_{\odot})=0.4(M_{bol\odot}-V-5-5log(\pi)+A_{v}-BC)$ (1)

We have used the updated BASTI-IAC evolutionary tracks888http://basti-iac.oa-
abruzzo.inaf.it/ (Hidalgo et al., 2018) generated, including overshooting and
diffusion, for the corresponding metallicities of the program stars. For
log(Teff), we have used our spectroscopic Teff estimates. Figure 7 shows the
appropriate evolutionary tracks corresponding to the Ba stars of our study.
Figure 7 shows the evolutionary track corresponding to HE 0507–1653, a CEMP-s
star of our study. We can see that the star falls towards the right side of
the evolutionary track. This is because the evolutionary tracks highly depend
on the opacity in the stellar atmospheres and the BASTI-IAC evolutionary
tracks are not calculated considering high carbon abundances. So, these
evolutionary tracks are not suitable for carbon-enhanced stars. As the
abundances of C or O or other $\alpha$-elements increase, formation of complex
molecules in the stellar atmosphere becomes more prominent. Due to this, it
may be possible that the opacity increases and the radiation pressure pushes
the outer layers to make the star larger. Hence, temperature decreases and the
star moves towards right side of the HR diagram. The use of the evolutionary
tracks customized to the observed abundances of the stars is out of the scope
of this paper. The masses of the program stars including log(L/L⊙) estimates,
are presented in Table LABEL:tab:mass_estimation. Due to the precise parallax
values provided by Gaia, the uncertainties in the estimation of Luminosities
are so small that we cannot even see the error bars in Figure 7. However, the
evolutionary tracks are available at mass intervals of 0.1 M⊙ and 0.5 M⊙ for
the mass ranges 0.8 – 3 M⊙ and 3 – 6 M⊙ respectively. So, we consider an
uncertainty in mass of $\pm$0.05 M⊙ and $\pm$0.25 M⊙ for the mass ranges 0.8 –
3 M⊙ and 3 – 6 M⊙ respectively.

Figure 7:  Hertzsprung-Russel diagram. Panel (a) shows evolutionary tracks for different masses at [Fe/H] $\sim$ –0.50. Red filled circle, green filled pentagon and blue filled triangle represent the positions of the Ba stars of our study. In panel (b), an evolutionary track for M = 0.8 M⊙ at [Fe/H] = –1.44 is shown. The red filled circle represents a CEMP-s star HE 0507–1653.  Table 12: Masses of the program stars Star Name | Parallax | Av | BC | log(L/L⊙) | log$T_{eff}$ | Mass (M⊙)
---|---|---|---|---|---|---
| (mas) |  |  |  |  |
BD+75 348 | 1.6672$\pm$0.0359 | 0.147608 | –0.320606 | 1.83$\pm$0.02 | 3.684 | 1.20
BD+09 3019 | 0.4105$\pm$0.0183 | 0.000000 | –0.690934 | 2.62$\pm$0.04 | 3.625 | 1.00
HD 238020 | 2.4767$\pm$0.0205 | 0.000000 | –0.225678 | 1.81$\pm$0.01 | 3.712 | 2.20
HE 0319–0215 | 0.0842$\pm$0.0158 | 0.034626 | –0.443833 | 2.80$\pm$0.15 | 3.667 | 0.80

###  7.4 Initial masses of the binary companion (primary)

We have performed a parametric-model-based analysis, using AGB yields of the
FRUITY999http://fruity.oa-teramo.inaf.it/ models (Straniero et al., 2006;
Cristallo et al., 2009, 2011, 2015) to estimate the initial masses of the
companions of the program stars. We have followed the procedure discussed in
Shejeelammal et al. (2020). We have calculated the s-process yields, using
FRUITY models, at different masses (1.3 – 6.0 M⊙) corresponding to the
metallicities of the program stars. Model yields are calculated considering
the conditions of standard 13C pockets (Cristallo et al., 2015) and no initial
rotational velocities of the AGB stars. The observed abundances of the
neutron-capture elements of a program star are then fitted with the following
parametric model function as discussed in Husti et al. (2009)–

$\left[\dfrac{X}{Fe}\right]=log\left(10^{[X/Fe]^{ini}}\times(1-10^{-d})+10^{[X/Fe]^{AGB}-d}\right)$
(2)

where, $\left[\dfrac{X}{Fe}\right]$ is the abundance of the element X in the
program star, $[X/Fe]^{ini}$ is the initial abundance (before mass-transfer)
of the element X in the program star, $[X/Fe]^{AGB}$ is the AGB yield of the
element X, $d$ is the dilution factor and a free parameter here. We find the
model which gives the best fit to the observational data by varying $d$ for
each set of AGB model yields with different masses. In order to find the best
fit, we calculated $\chi^{2}$ for each AGB model. The corresponding mass of
the AGB model for which we get the minimum value of $\chi^{2}$ is the required
mass of the companion AGB of the program star. The best-fitting models with
the AGB masses, corresponding dilution factors and minimum $\chi^{2}$ values
of the program stars are shown in Figure 8.

Figure 8:  Best fit parametric-models of the program stars. The points with
error bars indicate the observed abundances.

###  7.5 Mass distribution of primary and secondary stars

The mass distribution of Ba stars has been previously studied by several
groups (Han et al., 1995; Mennessier et al., 1997; Jorissen et al., 1998;
Escorza et al., 2017; Jorissen et al., 2019). Using the same procedures
discussed in Section 7.3 and Section 7.4, we have evaluated the mass
distributions of Ba stars (secondary stars) and the primaries (companion AGBs)
of both Ba and CEMP-s stars. For this analysis, we have selected a sample of
228 Ba stars and 36 CEMP-s stars from several sources in the literature. The
atmospheric parameters and elemental abundances of the Ba stars are collected
from Allen & Barbuy (2006), de Castro et al. (2016), Yang et al. (2016),
Karinkuzhi et al. (2018) and Shejeelammal et al. (2020). We have calculated
the [hs/Fe] values for the sample of 228 Ba stars and removed the ones having
[hs/Fe] $<$ 0.17. We believe that this lower limit (0.17) of [hs/Fe] will
ensure the selection of true Ba stars from the sample. The sample of Ba stars
ranges from [Fe/H] = –1.11 to +0.23. In Table 13, we have presented the list
of Ba stars used for this study. Column 6 of Table 13 gives the [hs/Fe] that
we have calculated and column 13 shows the classification. The atmospheric
parameters and elemental abundances of CEMP-s stars are taken from our
previously compiled CEMP-s stars’ list in Goswami et al. (2021) (Table 14). We
could not estimate the masses of the sample of CEMP-s stars due to the
inadequacy of the evolutionary tracks, as discussed in Section 7.3. Note that
the method of deriving the masses of Ba and CEMP-s stars using evolutionary
tracks in HR diagram has a serious drawback. The evolutionary tracks that we
use do not take care of the mass-transfer event taking place when the star was
in main-sequence stage.

Table 13: Masses of the Ba stars and initial masses of their AGB companions.

Star Name |  Teff | logg | [Fe/H] | [ls/Fe] | [hs/Fe] | [hs/ls] |  MBa |  M${}^{ini}_{AGB}$ | $\chi^{2}$ | dil | N | Type | Ref
---|---|---|---|---|---|---|---|---|---|---|---|---|---
| (K) | (cgs) |  |  |  |  |  (M⊙) |  (M⊙) |  |  |  |  |
BD-01302 | 4200 | 1.10 | -0.64 | -0.14 | 0.17 | 0.310 | - | 1.5 | 0.67 | 1.85697 | 5 | m | 1
BD-18821 | 5000 | 2.30 | -0.27 | 0.70 | 1.27 | 0.570 | 2.30 | 3.0 | 1.92 | 0.18030 | 5 | s | 1
BD-083194 | 4900 | 3.00 | -0.10 | 0.95 | 1.52 | 0.570 | 2.00 | - | - | - | 5 | s | 1

References: 1. de Castro et al. (2016).
Note: This table is available in its entirety online only. A portion is shown
here for guidance regarding its form and content.

Figure 9: Mass distributions of Ba stars and their progenitor AGBs (primary
stars). Panel (a) shows the mass distributions of mild and strong Ba stars.
Panel (b) shows the mass distribution of both mild and strong Ba stars as a
whole. Panel (c) shows the mass distributions of the primary stars of mild and
strong Ba stars. Panel (d) shows the mass distribution of the primary stars of
both mild and strong Ba stars as a whole.  Figure 10:  Mass distribution of
the primary companions of the CEMP-s stars.

####  7.5.1 Mass distribution of Ba stars

Han et al. (1995) from theoretical analysis showed that the average mass of
strong Ba stars is expected to be about 1.8 M⊙. They found a different peak
(1.7 M⊙) when all the Ba stars, including mild and strong Ba stars were
considered. Mennessier et al. (1997) advocated that mild Ba stars are clump
giants with 2.5 – 4.5 M⊙ mass range and these stars are a population of high
and low mass objects dominated by high mass objects with a small tail of less
massive objects. They found that strong Ba stars are giants in the mass range
1.0 – 3.0 M⊙. Jorissen et al. (1998) also reported different mass values for
mild and strong Ba stars. Supposing the mass of the companion WD as 0.60 $\pm$
0.04 M⊙, they estimated the masses of mild and strong Ba stars to be 1.90
$\pm$ 0.20 and 1.50 $\pm$ 0.20 respectively. Recently, Escorza et al. (2017)
derived the mass distribution of Ba stars using a large sample. In order to
find the masses of the Ba stars they generated the evolutionary tracks using
STAREVOL at a metallicity [Fe/H] = –0.25. They don’t see any difference in the
mass distribution of mild and strong Ba stars, unlike the previous claims.
They found that the mass distribution of Ba stars peak at 2.5 M⊙ with a tail
at higher masses upto 4.5 M⊙. Jorissen et al. (2019) also presented the mass
distribution of the Ba stars they studied using similar method as Escorza et
al. (2017), with the difference that they used the evolutionary tracks
calculated at the metallicities of the individual stars. Jorissen et al.
(2019) found that the Ba stars range from 1.0 – 3.0 M⊙ with a tail up to 5 M⊙.
This tail is comprised of mild Ba stars, mostly of [Fe/H] $\geq$ –0.1.
Jorissen et al. (2019) mentioned that in order to get the accurate mass
distribution, it is important to use the evolutionary tracks corresponding to
the metallicities of the respective stars.

Following the procedure described in Section 7.3 we have estimated the masses
of the sample of Ba stars. We have used the BASTI-IAC evolutionary tracks at
eleven different metallicities, [Fe/H] = +0.16, +0.05, –0.05, –0.15, –0.25,
–0.35, –0.45, –0.55, –0.63, –0.72, –0.95 covering the metallicity range of the
sample. We could estimate the masses of 205 Ba stars in total, out of which 52
are mild Ba stars and 153 are strong Ba stars. The [Fe/H] and Teff values of
the stars are collected from the literature. The derived masses of the Ba
stars are presented in Column 8 of Table 13. Similar to that of Escorza et al.
(2017) and Jorissen et al. (2019) we also found that mild and strong Ba stars
occupy the same mass range with the tails of strong and mild Ba stars going to
4.0$\pm$0.25 M$\odot$ and 4.5$\pm$0.25 M$\odot$ respectively (Figure 9).
Figure 11 shows the positions of the sample of Ba stars in the HR diagram with
evolutionary tracks of different masses at [Fe/H] = –0.25. Figure 9 shows the
whole sample of Ba stars without distinguishing between mild and strong Ba
stars. We found that the mass distribution of the Ba stars cannot be explained
by a single Gaussian distribution. Rather, the Ba stars are distributed
throughout the mass range with a disorderly manner. While Escorza et al.
(2017) found the masses of the Ba stars to peak at 2.5 M⊙, in our case we
found the average value of the distribution to be at 1.9 M⊙. Note that Escorza
et al. (2017) observed a lack of Ba stars in the mass range 1.0 – 2.0 M⊙. But,
neither our study nor the study by Jorissen et al. (2019) confirms that
observation. The difference seen in this study and the study by Escorza et al.
(2017) may come from two main sources. Firstly, the evolutionary tracks used
in both the studies are different. While Escorza et al. (2017) used STAREVOL
code to generate the evolutionary tracks, we have used the BASTI-IAC
evolutionary tracks (see Figure 9 of Escorza et al. (2017) for a comparison of
different sets of evolutionary tracks). Secondly, Escorza et al. (2017)
estimated the masses using the evolutionary tracks of a single [Fe/H] (=–0.25)
and our estimation is based on eleven different metallicities close to the
metallicities of the sample stars. For instance, Figure 11 shows how different
the evolutionary track of a particular mass can be at different metallicities.

Figure 11:  Hertzsprung-Russel diagram. Panel (a) shows evolutionary tracks
for different masses at [Fe/H] = -0.25. Yellow points represent the positions
of the Ba stars compiled from the literature. In panel (b), we have compared
the evolutionary tracks for M = 1.0 M⊙ & 2.0 M⊙ at three different
metallicities [Fe/H] = –0.95, –0.25 and +0.16.

####  7.5.2 Mass distribution of primary stars

We have estimated the masses of the companion AGBs of the sample of Ba and
CEMP-s stars following the same procedure described in Section 7.4. For this
study, we assume that the enhancement of neutron-capture elements in all these
stars is due to a mass-transfer event in a binary system where the slightly
massive companion (primary star) evolves through the AGB phase, produces
neutron-capture elements and transfers the elements to the secondary star,
which alters the surface composition of the secondary star significantly. If
the uncertainty in the abundance for a particular element is not reported in
the literature, we considered the uncertainty to be 0.2 dex. The number of
neutron-capture elements for which abundance estimates are available in the
literature range from 4 to 14 (column 12 of Table 13 and column 8 of Table
14).

Ba Stars: We could estimate the masses of the primary companions of 158 Ba
stars. Out of these, 52 are mild Ba stars and 106 are strong Ba stars. We have
divided the sample of Ba stars into seven groups based on the metallicities of
the stars and used FRUITY models at z = 0.020, 0.014, 0.010, 0.008, 0.006,
0.003, 0.002. We have presented the initial masses of the primary stars
(M${}^{ini}_{AGB}$), $\chi^{2}$, dilution factor (d) and the number of
elements used for the analysis (N) in columns 9, 10, 11 and 12 respectively of
Table 13. When we plot the histograms of primary companions’ masses for mild
and strong Ba stars separately, we can clearly see two peaks (Figure 9). The
mass range of primaries for mild Ba stars (1.5 $<$ M⊙ $<$ 6.0) is greater than
that (1.5 $<$ M⊙ $<$ 4.0) of strong Ba stars. The masses of primaries of
strong Ba stars peak at 2.5 M⊙ with a standard deviation of 0.51 M⊙ and that
of mild Ba stars peak at 3.7 M⊙ with a standard deviation of 1.03 M⊙. If we
consider the Ba star sample as a whole and not distinguish between mild and
strong Ba stars, then the primaries of Ba stars peak at 2.9 M⊙ with a standard
deviation of 1.15 M⊙ (Figure 9). We note that Stancliffe (2021) studied the
observed properties of barium star sample of de Castro et al. (2016)
considering models involving mass transfer from an AGB companion. The extent
of dilution of accreted material as the star evolves have been examined and
its impact on the surface abundances are discussed. He could best fit 32
objects from the sample using ejecta from 2.5 M⊙ AGB stars and 36 objects
using ejecta from 3 M⊙ AGB stars. The accretion masses are found to be broadly
consistent with the results obtained from hydrodynamical simulations of wind
mass transfer in binary systems of Liu et al. (2017)

CEMP-s Stars: The metallicities of the sample of 36 CEMP-s stars range from
[Fe/H] = –3.00 to –1.29. We have divided the sample into five groups based on
the metallicities of the stars. We have used FRUITY models at z= 0.001,
0.0003, 0.0001, 0.00005, 0.00002. We have presented the initial masses of the
primary stars (M${}^{ini}_{AGB}$), $\chi^{2}$, dilution factor (d) and the
number of elements used for the analysis (N) in columns 5, 6, 7 and 8
respectively of Table 14. The primary mass distribution of CEMP-s stars peaks
at 2.03 M⊙ with a standard deviation of 0.49 M⊙.

Table 14: Initial masses of the AGB companions of CEMP-s stars.

Star Name |  Teff |  log$g$ | [Fe/H] |  M${}^{ini}_{AGB}$ | $\chi^{2}$ | dil. | N
---|---|---|---|---|---|---|---
| (K) | (cgs) |  |  (M⊙) |  |  |
BD+04 2466 | 5100 | 1.80 | -1.92 | 3.0 | 3.61 | 0.26884 | 7
BS 16077-0077 | 5900 | 3.19 | -2.05 | 2.0 | 1.89 | 1.14484 | 9
CD-27 14351 | 4320 | 0.50 | -2.71 | 1.3 | 8.02 | 0.24628 | 8

Note: This table is available in its entirety online only. A portion is shown
here for guidance regarding its form and content.

###  7.6 Formation scenarios of mild and strong Ba stars

de Castro et al. (2016) considered that mild Ba stars are formed from the ISM
mildly enhanced with s-process elements. However, studies (Jorissen et al.,
1998, 2019) have shown that both mild and strong Ba stars are formed in binary
systems and AGB mass-transfer is responsible for the enhanced abundances of
heavy elements. So, we can safely discard this formation scenario. From
theoretical analysis, Han et al. (1995) showed that while most mild Ba stars
are formed from the wind accretion and wind exposure channels, the strong Ba
stars are formed from the wind accretion, wind exposure and stable Roche lobe
overflow (RLOF) channels. Yang et al. (2016) discussed two possible formation
scenarios for the formation of mild Ba stars- i) the mild enhancement could be
explained by weaker neutron-exposure in the progenitor AGB and/or ii) less
accretion efficiency due to longer orbital period which means larger distance
between the binary companions. However, from long term radial velocity
monitoring programs Jorissen et al. (1998, 2019) have shown that mild Ba stars
are not limited to long period systems only. The orbital periods of strong Ba
stars are generally shorter than that of mild Ba stars, but there is no tight
correlation. In fact, there is a clear overlap in the orbital periods of these
two subclasses. From Table 8 of Jorissen et al. (2019), we can see that the
period ranges of mild and strong Ba stars are 80 – 22065 days and 185.7 – 8523
days respectively. So, a scenario having longer orbital period cannot explain
the formation of a mild Ba star. However, we note that the ranges of both
orbital periods and progenitor masses of mild Ba stars are larger than that of
strong Ba stars.

The difference in the peaks of primaries for mild and strong Ba stars (Figure
9) indicates that companions of mild Ba stars are more massive than those of
strong Ba stars. This is not surprising because, from Figure 12, it can be
seen that massive (e.g. 4, 5, 6 M⊙) AGBs yield less than the low-mass AGBs
with same dilution factor. So, we can say that the dominant factor controlling
the abundance peculiarities of mild Ba stars is the initial mass of the
companion. Mass-transfer from 4.0 – 6.0 M⊙ AGB companions can describe the
formation of mild Ba stars. The WD masses of $\sim$ 1.0 M⊙ around Ba stars
also point towards a massive (5 M⊙) companion AGB (Jorissen et al., 2019).
However, there is an overlap from 1.3 – 4.0 M⊙ in the case of primary masses
of mild and strong Ba stars. In this mass range, the metallicity of the system
and dilution (hence the distance of the binary companions) play crucial roles
for the formation of mild Ba stars. From Figure 13, we see that the mild Ba
stars are distributed towards higher metallicities than that of strong Ba
stars and Figure 12 shows the metallicity dependence of the AGB models. At
higher metallicities, s-process efficiency decreases and hence AGB yields
decrease.

Figure 12:  Panel a: Comparison of the s-process AGB model yields obtained at
z = 0.006 for different masses using the same dilution factor (d). The points
with error bars indicate the observed abundances of BD+75 348. Panel b:
Comparison of the s-process AGB model yields obtained at two metallicities z =
0.02 and z = 0.002 for two masses M = 2.5 & 6.0 M⊙ using the same dilution
factor (d)  Figure 13: Metallicity distribution of the sample of mild and
strong Ba stars.

##  8 Conclusions

We have conducted detailed spectroscopic analysis of seven stars based on
high-quality, high-resolution spectra. Out of the seven program stars, we have
classified two stars (BD+09 3019 and BD+75 348) as strong Ba stars, one star
(HD 238020) as mild Ba star and the other four stars (HE 0319–0215, HE
0507–1653, HE 0930–0018 and HE 1023–1504) as CEMP-s stars. Note that HE
0507–1653 shows [Eu/Fe] $>$ 1.0 and according to the classification criteria
of Abate et al. (2016) this star belongs to the category of CEMP-r/s stars,
but the classification criteria that we proposed in Goswami et al. (2021)
place this star in the CEMP-s subclass. While we could not get a reasonable
fit for this object with i-process models with higher ($\geq$ 1012-15 cm-3)
neutron-densities, s-process AGB model with initial mass 2.0 M$\odot$
satisfactorily reproduces the observed abundance pattern. Kinematic analysis
shows that BD+75 348, HD 238020 and HE 0930–0018 belong to the thin disc
population, BD+09 3019 is a thick disc object and HE 0319–0215 & HE 0507–1653
show the probability of being halo objects.

We have derived the mass distribution of Ba stars and found that a single
Gaussian cannot describe the mass distribution. The average mass of the
distribution is found to be 1.9 M⊙ with the tails of strong and mild Ba stars
going up to 4.0 M$\odot$ and 4.5 M$\odot$ respectively. We confirm the
previous claim by Escorza et al. (2017) that mild and strong Ba stars occupy
the same mass range, but we do not confirm their claim that there is a lack of
Ba stars in the mass range 1.0 – 2.0 M⊙. Using a parametric-model-based
analysis we have derived the mass distributions of the AGB progenitors of the
Ba and CEMP-s stars. To the best of our knowledge, this is the first attempt
to derive the initial mass distribtuions of the primary companions of these
stars. We found that the mass distributions of the progenitor AGBs of the mild
and strong Ba stars peak at different values. The peaks of the progenitor mass
distributions of mild and strong Ba stars are at 3.7 M⊙ and 2.5 M⊙
respectively. We can, therefore, say that the initial mass of the companion
AGB is the dominant factor controlling the heavy elements’ enhancement in mild
Ba stars. However, we cannot neglect the orbital periods and metallicities of
the binary systems as clear overlap can be seen in the progenitor mass
distributions and orbital periods of mild and strong Ba stars. The mass
distribution of progenitor AGBs of CEMP-s stars peak at 2.03 M⊙ with a
standard deviation of 0.49 M⊙.

This work made use of the SIMBAD astronomical database, operated at CDS,
Strasbourg, France, the NASA ADS, USA and data from the European Space Agency
(ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia
Data Processing and Analysis Consortium (DPAC,
https://www.cosmos.esa.int/web/gaia/dpac/consortium). We thank the referee for
useful comments and suggestions. We are thankful to Melanie Hampel for
providing us with the i-process yields in the form of number fractions.
Funding from DST SERB project No. EMR/2016/005283 is gratefully acknowledged.

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Table 4. Equivalent widths (in mÅ) of Fe lines used for deriving atmospheric
parameters. Wavelength Element Elow log gf BD+75 348 BD+09 3019 HD 238020 HE
0319–0215 HE 0507–1653 HE 0930–0018 HE 1023–1504 (Å) (eV) 4187.04 Fe I 2.45
–0.548 - - - - 124.8 (6.12) - - 4202.03 1.48 –0.708 - - - - 179.4 (6.02) - -
4203.57 1.01 –3.869 - - 73.1 (6.72) - - - - 4210.343 2.48 –0.870 174.2 (7.17)
- 133.3 (6.95) - - - - 4213.65 2.85 –1.290 - - 97.4 (6.88) - - - - 4217.55
3.43 –0.510 - - 97.9 (6.75) - - - - 4222.21 2.45 –0.967 145.8 (6.87) - 125.3
(6.84) - - - - 4224.17 3.37 –0.410 - - 110.0 (6.90) - - - - 4233.60 2.48
–0.604 - - - - 115.5 (5.96) - - 4238.81 3.37 –0.280 133.2 (6.96) - 118.8
(6.98) - - - - 4239.36 3.64 –1.520 - - 51.4 (6.77) - - - - 4250.12 2.47 –0.405
- - 149.4 (6.72) - 134.6 (6.17) - - 4250.79 1.56 –0.710 - - 221.5 (6.70) - - -
- 4276.68 3.88 –1.210 85.5 (7.28) - 47.3 (6.63) - - - - 4282.40 2.18 –0.810 -
- 133.9 (6.54) - - - - 4377.79 3.27 –2.310 - 82.2 (6.85) - - - - 29.4 (6.04)
4387.89 3.07 –1.470 - - 70.5 (6.51) - - - - 4388.41 3.60 –0.590 108.9 (6.93) -
89.4 (6.72) - - - - 4430.61 2.22 –1.659 - - 125.3 (7.20) - - - - 4432.57 3.57
–1.600 63.2 (6.74) - 44.3 (6.61) - - - - 4433.22 3.65 –0.700 117.6 (7.29) -
89.9 (6.89) - - - - 4436.92 3.05 –2.110 - - 71.3 (7.13) - - - - 4446.83 3.69
–1.330 - - 66.6 (6.94) - - - - 4466.55 2.83 –0.590 176.8 (7.23) - 139.9 (7.06)
60.6 (5.00) - - 114.5 (5.64) 4476.02 2.85 –0.570 - - - 75.2 (4.99) - 137.0
(5.98) - 4482.74 3.65 –1.350 - - 70.4 (7.01) - - - - 4490.08 3.02 –1.580 101.5
(7.00) - 73.8 (6.62) - - - - 4517.52 3.07 –1.840 - - 65.3 (6.73) - - - -
4547.85 3.55 –0.780 100.5 (6.78) - 80.4 (6.57) - - - - 4587.13 3.57 –1.780
63.4 (6.89) - 48.3 (6.85) - - - - 4596.06 3.60 –1.640 - - 61.8 (7.02) - - - -
4602.00 1.61 –3.154 109.4 (7.04) - 82.4 (6.79) - - - - 4602.94 1.49 –1.950
163.3 (6.84) - 123.5 (6.53) - - - - 4637.50 3.28 –1.390 90.0 (6.78) - 78.0
(6.81) - - - - 4647.43 2.95 –1.310 - - 95.7 (6.81) - - - - 4704.95 3.69 –1.570
85.0 (7.29) - 52.9 (6.85) - - - - 4735.84 4.08 –1.220 - - 47.5 (6.80) - - - -
4736.77 3.21 –0.740 - - 113.1 (6.96) - - - - 4741.53 2.83 –2.000 - - 74.8
(6.81) - - - - 4788.76 3.24 –1.810 104.7 (7.47) - 66.6 (6.88) - - - - 4791.25
3.27 –2.510 71.1 (7.41) 75.5 (6.92) 33.7 (6.95) - - - - 4799.41 3.64 –2.230 -
- 31.0 (7.00) - - - - 4800.65 4.14 –1.260 79.7 (7.36) - 51.0 (6.98) - - - -
4802.88 3.64 –1.514 - 107.0 (6.87) - - - - - 4809.94 3.57 –2.720 - 50.3 (7.16)
- - - - - 4813.11 3.27 –2.890 - 49.4 (6.94) - - - - - 4817.78 2.22 –3.530 -
106.9 (6.99) - - - - - 4871.32 2.87 –0.410 - - - - 126.8 (6.21) - - 4874.35
3.07 –3.030 - 76.2 (7.19) - - - - - 4885.43 3.88 –1.095 - 106.7 (6.75) - - - -
- 4886.33 4.15 –0.685 81.8 (6.84) 119.6 (6.91) 63.5 (6.68) - - - - 4890.76
2.88 –0.430 - - 151.4 (7.01) - - - - 4892.86 4.22 –1.290 66.4 (7.18) - 36.2
(6.78) - - - - 4903.31 2.88 –1.080 155.1 (7.37) - 125.7 (7.17) 48.4 (4.87)
96.6 (6.17) - 107.6 (5.68) 4909.38 3.93 –1.327 81.7 (7.21) - 52.0 (6.82) - - -
- 4924.77 2.28 –2.220 122.9 (7.13) 188.4 (7.12) 96.6 (6.90) - 68.0 (5.96)
100.6 (6.06) 108.5 (6.02) 4927.42 3.57 –1.990 70.2 (7.20) - 39.6 (6.86) - - -
- 4930.31 3.96 –1.350 81.9 (7.27) - 56.9 (6.98) - - - - 4938.17 3.94 –1.018 -
- 72.9 (6.98) - - - - 4938.81 2.88 –1.077 - - 103.2 (6.60) - - - - 4939.69
0.86 –3.340 150.8 (7.11) - 115.2 (6.82) - - - - 4946.39 3.37 –1.170 - - 90.0
(6.91) - - - - 4950.11 3.42 –1.670 92.4 (7.19) - 66.9 (6.92) - - - - 4967.90
4.19 –0.534 - - 65.8 (6.61) - - - - 4969.92 4.22 –0.710 84.4 (6.99) - 60.9
(6.71) - - - - 4973.10 3.96 –0.950 - - 76.0 (7.00) - - - - 4982.50 4.10 0.164
- - - - 84.2 (6.03) - - 4985.25 3.93 –0.560 - 135.9 (6.75) - - - - - 4985.55
2.87 –1.331 - 189.4 (7.00) - - - - -

The numbers in the parenthesis in columns 5 to 11 give the derived abundances
from the respective line.

-continued Wavelength Element Elow log gf BD+75 348 BD+09 3019 HD 238020 HE 0319–0215 HE 0507–1653 HE 0930–0018 HE 1023–1504 (Å) (eV) 4994.13 0.92 –3.080 154.5 (6.97) - 122.6 (6.79) 74.4 (4.83) - - - 5002.79 3.40 –1.580 105.2 (7.38) - 65.4 (6.77) - - - - 5006.12 2.83 –0.615 - - - 84.2 (5.07) 112.5 (5.99) - - 5014.94 3.94 –0.250 - - 92.1 (6.67) - - - - 5049.82 2.28 –1.420 167.1 (7.15) - 132.4 (6.93) - - - - 5074.75 4.22 –0.200 - - 93.8 (6.95) - - - - 5079.22 2.20 –2.067 - - - 39.9 (4.83) 83.7 (6.01) 111.8 (5.98) - 5083.34 0.96 –2.958 160.5 (6.97) - 128.8 (6.83) - - - - 5090.77 4.26 –0.400 - - 75.0 (6.74) - - - - 5097.00 4.28 –0.196 - - 75.5 (6.57) - - - - 5110.41 0.00 –3.760 - - 152.6 (6.99) - - - - 5123.72 1.01 –3.068 - - 118.6 (6.74) - - - - 5126.19 4.26 –1.080 - - 60.5 (7.09) - - - - 5141.74 2.42 –2.150 137.3 (7.48) - 90.8 (6.79) - - - - 5150.84 0.99 –3.070 174.5 (7.32) - 128.7 (6.95) - - - - 5159.06 4.28 –0.820 69.0 (6.80) - 55.5 (6.76) - - - - 5162.27 4.18 0.020 - - 106.8 (6.98) - - - - 5166.28 0.00 –4.195 170.9 (7.14) - 131.1 (6.93) 93.0 (5.02) - - - 5171.60 1.49 –1.793 188.2 (6.80) - 151.8 (6.73) 109.7 (5.06) - - - 5187.91 4.14 –1.260 60.1 (6.90) - 38.3 (6.70) - - - - 5192.34 3.00 –0.421 - - - 75.3 (4.84) 112.8 (5.95) 152.5 (6.11) 139.8 (5.80) 5194.94 1.56 –2.090 - - 132.9 (6.72) 87.4 (4.91) - - 156.5 (5.88) 5195.47 4.22 0.018 111.5 (6.84) - 87.2 (6.56) - - - - 5198.71 2.22 –2.135 127.5 (6.98) - 102.4 (6.82) 41.2 (4.93) 80.3 (6.01) 124.7 (6.30) 123.5 (6.08) 5202.34 2.18 –1.838 - - - 54.3 (4.82) 105.7 (6.22) 135.7 (6.16) - 5215.18 3.27 –0.967 - 183.8 (7.01) - - - - - 5216.27 1.61 –2.150 156.2 (6.83) - 127.3 (6.70) - - - 139.8 (5.61) 5217.39 3.21 –1.162 114.9 (6.90) 149.9 (6.59) 93.8 (6.76) 40.2 (5.16) 81.0 (6.21) 105.8 (6.30) 99.1 (5.92) 5226.86 3.04 –0.555 - - - 62.7 (4.76) 99.8 (5.83) 144.6 (6.17) 131.1 (5.77) 5227.19 1.56 –1.228 - - - 122.6 (4.88) - - - 5228.38 4.22 –1.290 - - 44.7 (6.94) - - - - 5229.85 3.28 –1.136 120.7 (7.10) - 100.2 (6.97) - - - - 5232.94 2.94 –0.190 - - - 89.0 (4.83) 134.3 (6.11) - 163.9 (5.98) 5242.49 3.63 –0.840 - 153.1 (6.87) 81.4 (6.62) - 58.8 (5.94) 72.0 (5.93) 77.6 (5.74) 5243.78 4.26 –1.150 73.1 (7.18) - 47.7 (6.89) - - - - 5247.05 0.09 –4.946 - - - 35.5 (4.86) - - - 5253.46 3.28 –1.670 - 130.2 (6.87) - - 49.3 (6.19) - - 5263.31 3.27 –0.970 - - 102.9 (6.85) - - - - 5266.56 3.00 –0.490 174.8 (7.09) - 151.8 (7.10) 77.6 (4.95) 111.0 (5.96) - - 5281.79 3.04 –1.020 149.6 (7.27) 196.6 (6.92) 121.2 (7.06) 47.7 (4.95) 94.2 (6.15) 116.9 (6.14) 114.5 (5.86) 5283.62 3.24 –0.630 151.7 (7.16) - 125.2 (6.99) 58.8 (5.01) 102.5 (6.18) - - 5288.53 3.69 –1.670 69.2 (6.95) 105.4 (7.03) 46.4 (6.78) - - - - 5307.36 1.61 –2.987 124.6 (6.95) 183.3 (6.73) 99.4 (6.84) 43.8 (5.04) - - 115.8 (5.89) 5322.04 2.28 –3.030 89.7 (7.03) - 65.4 (6.92) - - - - 5324.18 3.21 –0.240 - - 145.5 (6.96) 76.8 (4.93) 108.8 (5.90) - - 5328.53 1.56 –1.850 - - - 94.7 (4.79) - - - 5339.93 3.27 –0.680 135.3 (6.91) - 113.7 (6.80) - 89.8 (5.97) - 112.0 (5.75) 5341.02 1.61 –2.060 - - - 84.3 (4.85) - - - 5364.87 4.45 0.220 116.2 (6.96) - 93.8 (6.73) - - - - 5365.40 3.57 –1.020 - - 73.6 (6.54) - - - - 5367.47 4.42 0.350 115.2 (6.77) - 99.1 (6.69) - 78.2 (6.02) - - 5369.96 4.37 0.350 - - - - 81.9 (6.04) - - 5373.71 4.47 –0.860 59.0 (6.85) - 45.7 (6.80) - - - - 5379.57 3.69 –1.480 84.8 (7.08) - 52.4 (6.70) - - - - 5389.48 4.42 –0.410 94.7 (7.08) - 68.2 (6.74) - - - - 5397.13 0.92 –1.993 - - 184.0 (6.68) - - - - 5400.50 4.37 –0.160 - - 96.3 (7.08) - - - - 5415.20 4.39 0.500 130.4 (6.90) - 107.3 (6.69) - 88.9 (6.06) - - 5424.07 4.32 0.520 152.7 (7.19) - 119.3 (6.86) - - - - 5445.04 4.39 –0.020 104.3 (6.85) 156.5 (7.07) 88.6 (6.77) - - - - 5462.96 4.47 –0.234 - 131.2 (7.00) - - - - - 5463.28 4.43 0.110 - 140.8 (6.75) - - - - - 5466.40 4.37 –0.630 101.2 (7.38) - 61.9 (6.78) - - - - 5473.90 4.15 –0.760 84.2 (6.88) - 63.2 (6.69) - - - - 5476.29 4.14 –0.935 - 85.0 (6.58) - - - - - 5487.74 4.32 –0.352 - - 70.7 (6.62) - - - - 5501.47 0.96 –2.950 173.9 (7.02) - 131.1 (6.71) - - - - 5506.78 0.99 –2.797 - - 136.1 (6.70) - - - - 5543.94 4.22 –1.140 - - 47.0 (6.82) - - - - 5546.51 4.37 –1.310 70.6 (7.40) - 36.6 (6.95) - - - -

-continued Wavelength Element Elow log gf BD+75 348 BD+09 3019 HD 238020 HE 0319–0215 HE 0507–1653 HE 0930–0018 HE 1023–1504 (Å) (eV) 5554.89 4.55 –0.440 - - 67.3 (6.89) - - - - 5557.98 4.47 –1.280 - - 38.8 (7.07) - - - - 5560.21 4.43 –1.190 60.9 (7.15) - 35.4 (6.87) - - - - 5562.71 4.43 –0.580 77.1 (6.86) - - - - - - 5567.39 2.61 –2.800 - - 62.0 (6.97) - - - - 5576.09 3.43 –1.000 - - 97.8 (6.88) - - - - 5586.76 3.37 –0.210 - - - 63.6 (4.80) 106.8 (5.95) - 132.9 (5.79) 5624.02 4.39 –1.480 60.8 (7.38) - 35.2 (7.10) - - - - 5624.54 3.42 –0.900 148.2 (7.48) - 108.8 (7.01) - - - - 5633.95 4.99 –0.270 68.8 (7.03) - 43.5 (6.70) - - - - 5653.86 4.39 –1.640 - 58.5 (7.22) - - - - - 5662.52 4.18 –0.573 98.3 (7.00) 148.1 (7.19) 74.5 (6.76) - - - - 5679.02 4.65 –0.920 71.8 (7.34) - 39.2 (6.90) - - - - 5731.76 4.26 –1.300 - - 43.2 (6.93) - - - - 5752.03 4.55 –0.864 59.2 (6.92) - 37.1 (6.69) - - - - 5753.12 4.26 –0.760 85.6 (7.00) 129.6 (7.20) 62.2 (6.76) - - 35.0 (6.01) - 5762.99 4.21 –0.450 - 143.0 (7.02) - - - - 61.8 (5.77) 5775.08 4.22 –1.298 71.8 (7.20) - 45.6 (6.94) - - - - 5806.73 4.61 –1.050 - 74.7 (7.15) - - - - - 5848.13 4.61 –1.010 - 47.2 (6.71) - - - - - 5859.59 4.55 –0.386 91.9 (7.09) - 55.6 (6.57) - - - - 5862.36 4.55 –0.051 - - - - - - 57.0 (5.72) 5930.18 4.65 –0.230 102.9 (7.28) - 67.9 (6.78) - - - - 5934.65 3.93 –1.170 - - 60.6 (6.77) - - - - 5976.78 3.94 –1.503 83.5 (7.30) - 56.9 (7.04) - - - - 5984.81 4.73 –0.443 - - 56.8 (6.85) - - - - 6003.01 3.88 –1.120 91.1 (6.99) - 67.4 (6.79) - - - - 6008.56 3.88 –1.291 94.0 (7.23) - 69.5 (7.01) - - - - 6027.05 4.08 –1.210 - - - - - 36.5 (6.27) - 6056.01 4.73 –0.460 - 90.2 (6.94) - - - - - 6082.71 2.22 –3.573 - 132.6 (7.23) - - - - - 6136.61 2.45 –1.400 - - - 76.8 (4.99) 109.8 (5.98) 145.9 (6.09) - 6137.69 2.59 –1.403 158.8 (7.03) - 126.6 (6.83) 71.8 (5.08) 97.1 (5.92) 135.6 (6.11) - 6151.62 2.18 –3.299 - 128.4 (6.83) - - 29.3 (6.12) 49.0 (6.06) - 6180.20 2.73 –2.780 - - - - - 43.8 (6.19) 37.7 (5.78) 6226.73 3.88 –2.220 - 35.6 (6.80) - - - - - 6230.72 2.56 –1.281 - - 134.7 (6.82) 71.1 (4.90) 110.4 (6.00) - - 6246.32 3.60 –0.960 118.1 (7.02) - 95.3 (6.87) - - - - 6252.56 2.40 –1.687 157.0 (7.02) - 122.3 (6.77) 58.9 (4.89) 103.6 (6.07) 137.1 (6.14) - 6254.26 2.28 –2.480 139.3 (7.31) - 109.3 (7.14) - - - - 6256.36 2.45 –2.620 123.1 (7.34) - - - - - - 6265.13 2.18 –2.550 147.9 (7.41) - 95.4 (6.81) - - - - 6318.02 2.45 –2.228 - - - - 74.6 (6.13) 100.9 (6.14) - 6335.33 2.20 –2.230 - - - 42.1 (4.90) 77.1 (5.87) - 136.0 (6.03) 6411.65 3.65 –0.820 - 173.6 (7.01) - - - - - 6421.35 2.28 –2.027 154.8 (7.11) - 119.0 (6.86) - 88.2 (5.96) - - 6518.37 2.83 –2.750 - 127.3 (7.14) - - - - - 6593.87 2.43 –2.422 - - - - 64.1 (6.10) 84.1 (6.03) - 6739.52 1.56 –4.950 - 72.8 (6.90) - - - - - 4233.17 Fe II 2.58 –2.000 - - 125.2 (6.91) - - - - 4491.40 2.86 –2.700 95.9 (7.14) - 81.3 (6.69) - - - - 4515.34 2.84 –2.480 92.5 (6.80) - 87.7 (6.63) 36.5 (4.87) 60.8 (6.00) 29.3 (6.15) - 4541.52 2.86 –3.050 74.5 (6.90) - 78.1 (6.94) - - - - 4520.22 2.81 –2.600 100.5 (7.09) - 87.5 (6.70) - - - - 4576.34 2.84 –3.040 - - 75.0 (6.84) - - - - 4620.52 2.83 –3.280 71.0 (7.02) - 64.0 (6.78) - - - - 4923.93 2.89 –1.320 159.1 (6.99) 152.6 (6.96) 148.4 (6.81) 86.4 (4.99) 115.6 (6.19) 71.6 (6.17) - 5120.35 2.83 –4.214 - - 40.4 (7.15) - - - - 5197.58 3.23 –2.100 109.2 (7.18) - 90.0 (6.64) 39.2 (4.98) 61.4 (6.04) - 77.3 (5.89) 5234.62 3.22 –2.050 - 78.1 (6.85) - 40.5 (4.94) 66.9 (6.10) 20.2 (6.00) 75.7 (5.79) 5256.94 2.89 –4.250 44.0 (7.42) - 20.7 (6.77) - - - - 5264.81 3.23 –3.190 49.7 (6.86) 32.7 (7.06) 49.4 (6.75) - - - - 5276.00 3.20 –1.940 - - - 44.4 (4.90) - - - 5414.07 3.22 –3.790 42.2 (7.28) - 27.3 (6.82) - - - - 5425.26 3.20 –3.360 60.0 (7.23) - 44.1 (6.77) - - - - 5534.85 3.25 –2.930 69.3 (7.06) - 63.9 (6.83) - - - - 6147.74 3.89 –2.721 - - 60.3 (7.22) - - - - 6238.39 3.89 –2.630 - - 42.8 (6.73) - - - -

Table 6. Equivalent widths (in mÅ) of lines used for calculation of elemental
abundances. Wavelength Element Elow log gf BD+75 348 BD+09 3019 HD 238020 HE
0319–0215 HE 0507–1653 HE 0930–0018 HE 1023–1504 (Å) (eV) 5682.633 Na I 2.10
–0.700 115.8 (6.25) 172.5 (6.08) 64.4 (5.62) 22.4 (4.71) 45.2 (5.19) 112.1
(5.39) 51.5 (5.06) 5688.205 2.10 –0.450 140.3 (6.42) 170.6 (5.81) 87.1 (5.77)
25.3 (4.53) 58.7 (5.17) 136.8 (5.43) - 6154.23 2.10 –1.560 59.1 (6.14) - 16.1
(5.50) - - - - 6160.75 2.10 –1.260 88.1 (6.30) - 30.1 (5.55) - 19.7 (5.21) - -
4571.10 Mg I 0.00 –5.691 181.2 (7.59) - 131.6 (7.27) 62.7 (5.51) 113.8 (6.62)
- - 4702.99 4.35 –0.666 178.2 (7.37) - 161.8 (7.38) - - - - 5528.40 4.35
–0.620 191.2 (7.39) - 163.1 (7.31) - 143.8 (6.81) - - 5711.09 4.35 –1.833
101.3 (7.18) - 86.6 (7.19) - 61.1 (6.62) 105.1 (6.69) - 6318.72 5.11 –1.730 -
170.8 (8.31) - - - - - 6237.32 Si I 5.61 –0.530 - - 35.6 (6.31) - - - -
4283.01 Ca I 1.89 –0.224 155.1 (6.04) - 132.8 (6.01) - - - - 4318.65 1.90
–0.208 142.4 (5.84) - 125.7 (5.87) - 110.2 (5.30) - - 4425.44 1.88 –0.385
152.8 (6.12) - 118.6 (5.87) - - - - 4434.96 1.89 –0.029 169.5 (5.98) - - - - -
- 4585.86 2.53 –0.186 - - 116.7 (6.23) - - - - 5260.39 2.52 –1.900 - 69.7
(5.65) - - - - - 5512.98 2.93 –0.290 - - 62.6 (5.49) - - 120.1 (5.33) -
5581.97 2.52 –0.710 - - 84.7 (5.94) - - - - 5588.75 2.53 0.210 136.2 (5.71) -
126.8 (5.90) 57.9 (4.39) - - - 5590.11 2.52 –0.710 108.1 (6.07) 159.3 (5.64)
81.5 (5.86) - 62.8 (5.32) 128.6 (5.36) 98.5 (5.67) 5594.46 2.52 –0.050 143.5
(6.08) - 111.1 (5.85) 59.9 (4.68) 113.4 (5.68) - 122.3 (5.48) 5598.48 2.52
–0.220 - - 104.9 (5.88) - - - - 5601.28 2.53 –0.690 125.5 (6.40) - 90.7 (6.05)
- - - - 5857.45 2.93 0.230 138.9 (6.14) - 105.6 (5.86) - 95.0 (5.47) - 107.9
(5.39) 6102.72 1.88 –0.890 139.4 (6.00) - 112.8 (5.96) 40.6 (4.24) - - -
6122.22 1.89 –0.409 184.7 (6.20) - 142.7 (6.04) - - - - 6162.17 1.90 0.100 - -
162.3 (5.83) - - - - 6166.44 2.52 –0.900 82.6 (5.68) - 56.5 (5.49) - 45.5
(5.15) 115.1 (5.31) - 6169.04 2.52 –0.550 105.9 (5.78) - 74.3 (5.51) - 64.9
(5.18) 154.0 (5.45) - 6169.56 2.53 –0.270 125.9 (5.90) - 92.9 (5.64) - 78.5
(5.18) 180.0 (5.43) - 6439.07 2.53 0.470 156.7 (5.64) - 136.6 (5.71) 84.7
(4.65) 114.5 (5.12) - - 6449.81 2.52 –0.550 116.4 (5.95) - 90.4 (5.83) - - - -
6572.78 0.00 –4.290 - - 37.8 (5.69) - - 120.6 (5.13) - 4533.24 Ti I 0.85 0.476
133.6 (4.33) - 108.6 (4.32) - - - - 4820.41 1.50 –0.441 - 179.5 (4.92) - - - -
- 4840.87 0.90 –0.509 97.8 (4.40) - 74.1 (4.39) - 67.0 (4.00) 111.7 (3.25) -
4926.15 0.82 –2.170 28.5 (4.57) - - - - 42.2 (3.64) - 4937.73 0.81 –2.254 -
115.5 (4.65) - - - - - 4981.73 0.85 0.504 163.8 (4.66) - 121.6 (4.46) - - - -
4991.06 0.84 0.380 152.2 (4.58) - 118.3 (4.49) - - - - 4999.50 0.83 0.250 - -
118.2 (4.60) - - - - 5016.16 0.85 –0.574 112.1 (4.68) - 82.2 (4.56) - - - -
5024.84 0.82 –0.602 113.3 (4.69) - 77.3 (4.44) - 58.1 (3.78) 111.5 (3.17) 99.1
(3.79) 5064.65 0.05 –0.991 145.8 (4.81) - 101.4 (4.52) - - - - 5173.74 0.00
–1.118 - - 91.6 (4.32) - - - - 5192.97 0.02 –1.006 161.0 (5.02) - 107.6 (4.61)
- - - - 5210.39 0.05 –0.884 146.0 (4.63) - 108.2 (4.54) 62.5 (3.16) 90.7
(3.87) - 161.7 (4.09) 5460.50 0.05 –2.880 45.7 (4.60) - 13.9 (4.40) - - 57.7
(3.42) - 5918.53 1.07 –1.460 - - - - - 57.2 (3.42) - 5922.11 1.05 –1.466 51.1
(4.46) - 23.0 (4.35) - - 69.1 (3.56) 52.0 (3.98) 5978.54 1.87 –0.496 78.7
(4.98) - 23.1 (4.30) - - 69.6 (3.76) - 4163.65 Ti II 2.59 –0.400 - - 100.2
(4.62) - - - - 4443.79 1.08 –0.700 - - 157.3 (4.33) - 148.1 (3.90) 122.9
(3.17) - 4450.48 1.08 –1.450 137.1 (4.72) - - - - - - 4464.45 1.16 –2.080 - -
104.0 (4.72) - - - - 4468.51 1.13 –0.600 - - 158.6 (4.29) - - - - 4470.86 1.16
–2.280 - - 95.9 (4.70) - - - - 4501.27 1.12 –0.750 - - 152.9 (4.35) - - - -
4518.33 1.08 –2.555 83.0 (4.48) - 74.6 (4.31) - - - - 4563.76 1.22 –0.960 - -
144.6 (4.53) 118.2 (3.43) - 121.9 (3.57) - 4571.97 1.57 –0.530 - - 158.4
(4.67) - - - - 4589.96 1.24 –1.790 117.5 (4.76) - 110.0 (4.64) - - - - 4764.53
1.24 –2.770 77.1 (4.70) - 58.7 (4.29) - 48.1 (3.89) - - 4779.98 2.05 –1.370
95.5 (4.68) - 82.6 (4.36) 60.0 (3.18) 76.5 (4.03) - - 4798.52 1.08 –2.430 - -
70.3 (4.03) - 65.0 (3.71) - - 4805.09 2.06 –1.100 - - 102.6 (4.62) 73.3 (3.29)
86.4 (4.01) 57.6 (3.60) - 4865.61 1.12 –2.610 81.7 (4.49) - 66.4 (4.16) - 49.0
(3.60) - - 5129.15 1.89 –1.390 - - 91.2 (4.37) - - - - 5154.07 1.57 –1.920
115.4 (5.08) - 88.8 (4.47) - - - -

The numbers in the parenthesis in columns 5 to 11 give the derived abundances
from the respective line.

-continued Wavelength Element Elow log gf BD+75 348 BD+09 3019 HD 238020 HE 0319–0215 HE 0507–1653 HE 0930–0018 HE 1023–1504 (Å) (eV) 5185.91 1.89 –1.350 99.0 (4.50) - 84.4 (4.15) - 64.0 (3.51) - - 5226.54 1.57 –1.300 - - 112.9 (4.43) - - 76.0 (3.44) - 5336.77 1.58 –1.700 108.8 (4.68) - 92.7 (4.33) - 95.0 (4.17) - - 5381.02 1.57 –2.080 - - 79.4 (4.38) - - - - 5418.75 1.58 –1.999 84.5 (4.41) - 70.1 (4.09) - - - - 4545.95 Cr I 0.94 –1.370 - - 92.5 (5.06) - - - - 4616.12 0.98 –1.190 137.9 (5.44) - 92.8 (4.91) - - - - 4626.17 0.97 –1.320 - - 83.2 (4.77) - - - - 4646.16 1.03 –0.700 148.8 (5.19) - 104.6 (4.79) - - - - 4651.28 0.98 –1.460 - - 82.2 (4.89) - - - - 4652.16 1.00 –1.030 138.8 (5.30) - 105.2 (5.10) - - - - 5206.04 0.94 0.019 - - 172.3 (5.02) 86.8 (3.29) 125.8 (4.01) - - 5296.69 0.98 –1.400 135.3 (5.32) - 95.3 (5.03) - 75.6 (4.32) - - 5298.27 0.98 –1.150 - - 105.8 (5.04) 43.1 (3.29) 86.5 (4.33) - - 5300.74 0.98 –2.120 90.7 (5.06) - 56.7 (4.85) - 30.2 (4.11) 82.8 (3.65) 63.9 (4.05) 5345.80 1.00 –0.980 - - 111.9 (5.03) - - 173.0 (3.92) - 5348.31 1.00 –1.290 125.2 (5.01) - 99.5 (5.04) 22.7 (2.95) 72.2 (4.16) 130.7 (3.64) 100.8 (3.90) 5409.78 1.03 –0.720 169.6 (5.27) - 129.9 (5.18) - 104.2 (4.36) - - 4558.65 Cr II 4.07 –0.660 - - 80.8 (5.01) - - - - 4121.31 Co I 0.92 –0.320 - - 124.3 (4.40) - - - - 4813.47 3.22 0.050 66.3 (4.56) 79.8 (4.23) 36.0 (4.20) - 15.7 (3.52) 37.0 (3.57) 29.7 (3.47) 5342.69 4.02 0.690 - - 22.1 (4.08) - - - - 5483.34 1.71 –1.490 - - 61.1 (4.52) - - 58.1 (3.40) - 6117.00 1.79 –2.490 23.0 (4.41) - - - - - - 4714.41 Ni I 3.38 0.260 - - 108.9 (5.79) - - - - 4756.51 3.48 –0.270 98.2 (5.85) - 68.4 (5.39) - 47.5 (4.73) - - 4855.41 3.54 0.000 107.1 (5.84) - 83.4 (5.57) - - - - 4980.17 3.61 0.070 116.6 (6.04) - 88.9 (5.69) - - - 101.7 (5.38) 5035.36 3.64 0.290 102.0 (5.51) - 82.6 (5.34) - 55.8 (4.51) - - 5080.53 3.66 0.330 104.9 (5.55) - 87.1 (5.43) - - - - 5081.11 3.85 0.300 88.6 (5.41) - 79.4 (5.47) - 61.6 (4.86) - - 5137.07 1.68 –1.990 - - 103.0 (5.92) - 73.0 (4.92) - - 5146.48 3.71 0.120 94.9 (5.57) - 78.1 (5.45) - - 139.0 (5.67) - 5476.90 1.83 –0.890 173.0 (5.77) - 145.0 (5.78) - - - - 6175.36 4.09 –0.530 - - 30.9 (5.40) - - 61.9 (5.66) - 6176.81 4.09 –0.530 78.3 (6.17) - 45.5 (5.71) - - - - 6177.24 1.83 –3.500 43.6 (5.77) - 13.8 (5.40) - - 50.0 (5.39) - 6643.63 1.68 –2.300 134.0 (6.05) 178.9 (5.65) 103.8 (5.97) - - - 129.2 (5.14) 6767.77 1.83 –2.170 115.1 (5.72) - 86.9 (5.63) - - - - 5105.54 Cu I 1.39 –1.516 - - 96.4 (3.89) - - - - 5218.20 3.82 0.476 69.7 (3.66) 92.0 (3.62) - - 17.4 (2.55) 41.2 (2.85) - 4722.15 Zn I 4.03 –0.338 - - 66.8 (3.78) - - - - 4810.53 4.08 –0.137 85.8 (4.12) 79.3 (3.87) 70.3 (3.72) - 56.3 (3.21) 43.0 (3.30) 49.7 (2.74) 4607.33 Sr I 0.00 –0.570 - - - - - - - 4872.49 1.80 –0.200 - 98.0 (3.99) - - - - - 4215.52 Sr II 0.00 –0.145 - - 338.1 (2.27) - - - - 4317.30 Y II 0.71 –1.380 - 177.2 (3.66) - - - - - 4854.86 0.99 –0.380 140.1 (3.10) - 62.1 (1.27) 71.0 (0.76) 98.3 (1.97) 81.0 (1.32) - 4883.68 1.08 0.070 183.9 (3.27) - 75.9 (1.28) - - - - 4900.12 1.03 –0.090 - - 75.5 (1.38) - - - - 5087.42 1.08 –0.170 135.7 (2.86) - 62.6 (1.14) - - - - 5200.41 0.99 –0.570 128.7 (2.98) - 54.9 (1.24) - 87.8 (1.82) - 113.0 (1.52) 5205.72 1.03 –0.340 150.9 (3.19) - 63.9 (1.27) - 97.1 (1.87) - - 5289.81 1.03 –1.850 78.2 (3.08) - - - 43.4 (2.09) 18.5 (1.62) - 5402.77 1.84 –0.510 83.0 (2.81) - 14.8 (1.12) - 62.4 (2.10) - - 5544.61 1.74 –1.090 82.8 (3.25) - - - - - - 5662.93 1.94 0.160 121.9 (3.14) 178.5 (3.88) 51.7 (1.94) 59.1 (0.83) 81.1 (1.97) 60.2 (1.64) 108.3 (1.82) 5728.89 1.84 –1.120 64.5 (2.95) - - - - - - 4739.48 Zr I 0.65 0.230 - - 9.4 (1.97) - - 66.0 (1.57) - 4772.32 0.62 0.040 68.6 (3.13) 152.6 (2.96) 8.1 (2.05) - 40.4 (2.78) - - 4805.89 0.69 –0.420 41.9 (3.11) 97.2 (2.85) - - 14.3 (2.65) - - 6134.59 0.00 –1.280 57.2 (3.25) 171.7 (3.13) - - - - - 4379.74 Zr II 1.53 –0.356 99.3 (3.44) - 44.2 (1.93) - - - - 4457.42 1.37 –0.610 - - - 21.9 (0.63) - - - 4962.31 0.97 –2.000 70.6 (3.49) - - - 41.4 (2.62) - 59.3 (2.23) 5112.30 1.67 –0.590 - - - - 79.6 (2.91) - - 5350.09 1.83 –1.240 53.9 (3.31) - - - - - - 5350.37 1.77 –1.276 - - 8.2 (1.98) - - - - 4257.12 Ce II 0.46 –1.116 69.5 (2.74) - - - 59.0 (2.26) - - 4336.24 0.70 –0.564 - 127.3 (2.89) - - - - - 4427.92 0.54 –0.460 - - 30.7 (1.22) - 74.8 (2.11) - - 4460.21 0.17 0.478 - - - - 149.0 (2.31) - -

-continued Wavelength Element Elow log gf BD+75 348 BD+09 3019 HD 238020 HE 0319–0215 HE 0507–1653 HE 0930–0018 HE 1023–1504 (Å) (eV) 4483.89 0.86 0.010 86.8 (2.55) - 25.6 (0.97) - 77.4 (2.07) - - 4486.91 0.30 –0.474 115.4 (3.14) - 34.0 (1.04) - - - - 4515.85 1.06 –0.612 65.0 (2.76) - 9.3 (1.24) - - - - 4560.96 0.68 –0.546 101.4 (3.28) - - - - - - 4562.36 0.48 0.081 120.4 (2.88) - 49.3 (1.04) - 96.3 (2.06) - - 4628.16 0.52 0.008 - - 42.5 (0.99) - - - - 4725.07 0.52 –1.204 74.5 (2.92) - - - 50.8 (2.12) 28.6 (1.54) - 4874.00 1.11 –0.892 67.3 (3.10) - - - 41.0 (2.26) - 82.1 (2.44) 5187.46 1.21 –0.104 91.9 (3.02) - - 43.6 (0.92) 66.1 (2.15) 45.2 (1.66) 109.7 (2.34) 5274.23 1.04 –0.323 92.5 (3.03) 145.6 (3.16) 15.6 (1.15) - - - - 5330.56 0.87 –0.760 83.5 (3.02) 136.0 (3.18) - 36.6 (0.94) 57.0 (2.17) 22.8 (1.40) 96.1 (2.15) 5472.28 1.25 –0.544 77.3 (3.08) - - - - - - 6043.37 1.21 –0.772 72.2 (3.06) - - - - - - 5219.05 Pr II 0.79 –0.240 73.4 (2.02) 139.7 (2.48) - - - - 101.7 (1.53) 5220.11 0.80 0.160 93.5 (2.16) - 17.9 (0.36) - - - 118.6 (1.54) 5259.73 0.63 0.080 - - - - - 35.5 (0.35) - 5292.62 0.65 –0.300 90.4 (2.33) 167.2 (2.77) 17.6 (0.63) - - - - 5322.77 0.48 –0.315 102.6 (2.44) 176.4 (2.69) - 43.4 (0.48) - 32.5 (0.48) 128.3 (1.73) 6165.89 0.92 –0.205 68.0 (1.90) - - - 47.0 (1.25) - - 4061.08 Nd II 0.47 0.550 - - 69.3 (1.08) - - - - 4109.07 0.06 0.280 - - 77.1 (1.14) - - - - 4109.45 0.32 0.300 - - 79.5 (1.49) - - - - 4451.56 0.38 –0.040 124.6 (2.80) - - - - - - 4451.98 0.00 –1.340 - - 35.4 (1.40) 53.4 (0.93) 78.9 (2.25) 47.6 (1.11) 95.9 (1.69) 4594.45 0.20 –1.550 65.4 (2.45) - - 23.5 (0.48) 52.0 (1.93) - - 4645.76 0.56 –0.750 84.6 (2.61) - - - - - - 4706.54 0.00 –0.880 - - 36.9 (0.94) - 86.9 (1.93) - - 4797.15 0.56 –0.950 78.4 (2.59) - 11.4 (0.90) 29.8 (0.45) 57.0 (1.84) 27.2 (1.07) 96.3 (1.90) 4811.34 0.06 –1.140 - 160.4 (2.77) 28.1 (1.05) - - 47.6 (0.95) - 4825.48 0.18 –0.860 - - - - 89.1 (2.15) 51.9 (0.91) - 5092.79 0.38 –0.610 94.0 (2.37) - 20.6 (0.66) - - - - 5132.33 0.56 –0.770 - - 16.7 (0.90) - - - - 5212.36 0.20 –0.870 112.0 (2.84) - - 67.0 (0.83) 78.3 (1.81) 52.8 (0.93) 134.6 (2.01) 5255.51 0.20 –0.820 - - - 72.6 (0.94) 87.5 (1.99) 47.9 (0.79) 137.8 (2.00) 5293.16 0.82 –0.060 - - 30.2 (0.84) 66.9 (0.79) 88.0 (1.98) 43.0 (0.80) 130.4 (1.94) 5311.45 0.99 –0.420 94.2 (2.89) - - - - - - 5319.81 0.55 –0.210 120.7 (2.78) - 34.5 (0.78) - - - - 5356.97 1.26 –0.250 71.7 (2.46) - - - 71.1 (2.24) - - 5442.26 0.68 –0.910 75.3 (2.49) - - - 66.3 (2.08) - - 5688.52 0.99 –0.250 92.4 (2.59) - 15.8 (0.79) - 72.2 (1.90) 40.5 (1.16) - 5825.86 1.08 –0.760 - 115.8 (2.85) - - - - - 4318.93 Sm II 0.28 –0.613 - - 34.8 (0.71) 50.1 (0.28) - - 92.8 (1.14) 4424.34 0.48 –0.260 - - - 55.0 (0.30) 89.9 (1.81) 44.7 (0.41) - 4458.51 0.10 –1.110 - - - 40.2 (0.17) - 42.1 (0.69) - 4499.48 0.25 –1.413 - 128.8 (2.61) 9.4 (0.67) - - - - 4519.63 0.54 –0.751 - - 17.0 (0.63) - - - - 4566.20 0.33 –1.245 68.7 (2.15) 141.9 (2.79) - - - - - 4577.69 0.25 –1.234 67.6 (2.00) - 17.3 (0.80) - - - - 4704.40 0.00 –1.562 - - - - 59.4 (1.60) - - 4791.58 0.10 –1.846 - 139.7 (2.94) - - - - - 4815.81 0.18 –1.420 - - - 23.2 (0.01) 52.1 (1.48) - - 4854.37 0.38 –1.873 40.2 (2.10) - - - 23.5 (1.51) - 54.6 (1.34) 4103.31 Dy II 0.10 –0.346 81.0 (1.49) - 46.4 (0.53) - - - - 4923.17 0.10 –2.384 - 76.7 (2.43) - - - - - 4093.16 Hf II 0.45 –1.090 89.5 (2.33) - - - - - -

Table 13. Masses of the Ba stars and initial masses of their AGB companions.
Star Name Teff logg [Fe/H] [ls/Fe] [hs/Fe] [hs/ls] MBa M${}^{ini}_{AGB}$
$\chi^{2}$ dil N Type Ref (K) (cgs) (M⊙) (M⊙) BD-01302 4200 1.10 -0.64 -0.14
0.17 0.310 - 1.5 0.67 1.85697 5 m 2 BD-18821 5000 2.30 -0.27 0.70 1.27 0.570
2.30 3.0 1.92 0.18030 5 s 2 BD-083194 4900 3.00 -0.10 0.95 1.52 0.570 2.00 - -
- 5 s 2 BD-094337 4800 2.60 -0.24 1.31 1.50 0.190 1.80 2.5 0.26 0.42156 5 s 2
BD-142678 5200 3.10 0.01 0.94 0.94 0.010 3.00 - - - 5 s 2 BD+092384 4900 2.50
-0.98 0.57 0.88 0.310 0.80 3.0 0.90 0.46181 5 s 2 BD+185215 6300 4.20 -0.53
1.12 1.15 0.020 1.00 2.5 2.51 0.58244 14 s 1 CD-38585 4800 2.60 -0.52 1.00
1.54 0.540 0.80 2.0 0.41 0.17203 5 s 2 CD-267844 5100 2.80 0.02 0.55 0.39
-0.160 2.50 3.0 0.32 0.38827 5 m 2 CD-272233 4700 2.40 -0.25 0.81 1.10 0.290
1.20 2.0 0.85 0.24246 5 s 2 CD-298822 5100 2.80 0.04 0.94 1.15 0.220 3.00 - -
- 5 s 2 CD-308774 4900 2.30 -0.11 0.50 0.43 -0.070 2.30 3.0 0.73 0.62088 5 m 2
CD-309005 4700 2.30 0.05 0.66 0.73 0.070 2.80 3.0 2.30 0.04737 5 s 2 CD-346139
4900 2.20 -0.07 0.63 0.66 0.030 3.00 - - - 5 s 2 CD-347430 4900 2.60 0.01 0.59
0.52 -0.080 2.40 3.0 0.72 0.25785 5 m 2 CD-463977 4900 2.60 -0.10 0.68 0.67
-0.010 2.20 - - - 5 s 2 CD-538144 4800 2.30 -0.19 0.81 1.16 0.340 1.70 2.5
3.21 0.02395 5 s 2 CD-611941 4800 2.40 -0.20 0.71 1.26 0.560 2.20 - - - 5 s 2
CPD-621013 5100 2.60 -0.08 0.72 0.94 0.220 2.60 - - - 5 s 2 CPD-644333 4900
2.60 -0.10 1.12 1.78 0.660 1.50 - - - 5 s 2 HD 107 6440 4.10 -0.36 0.49 0.59
0.100 2.60 - - - 13 m 1 HD 749 4610 2.80 0.17 0.84 1.09 0.250 1.30 - - - 14 s
1, 2 HD 4084 4800 2.80 -0.42 0.85 0.89 0.040 1.20 2.5 1.76 0.78980 5 s 2 HD
5322 4800 1.70 -0.18 0.03 0.21 0.180 4.50 5.0 0.27 0.10268 5 m 2 HD 5424 4728
2.50 -0.43 1.28 1.84 0.560 1.00 2.5 5.80 0.01784 16 s 1, 2, 4 HD 5825 5000
2.70 -0.48 0.75 1.11 0.360 2.20 2.5 0.48 0.67253 5 s 2 HD 8270 5940 4.20 -0.42
0.93 0.92 -0.010 0.90 4.0 1.74 0.08759 14 s 1 HD 11353 4592 2.10 0.04 - 0.38 -
2.50 4.0 2.03 0.49563 4 m 3 HD 11658 4699 2.60 0.00 -0.14 0.22 0.360 1.60 4.0
1.51 1.90483 5 m 3 HD 12392 4987 3.40 -0.38 1.12 1.43 0.310 1.10 2.5 2.32
0.12114 11 s 1, 2, 4 HD 13551 5870 4.00 -0.24 0.75 0.75 -0.010 1.40 2.5 0.80
0.72091 14 s 1 HD 13787 4966 2.90 0.00 0.35 0.54 0.190 2.40 4.0 1.22 0.09316 5
m 3 HD 15589 4900 3.10 -0.27 0.94 1.61 0.670 1.40 - - - 5 s 2 HD 16458 4550
1.80 -0.64 1.21 1.46 0.250 1.00 2.5 8.08 0.14053 11 s 4 HD 17067 4200 1.10
-0.61 0.83 1.33 0.500 1.00 2.5 3.66 0.38338 5 s 2 HD 18182 4900 2.40 -0.17
0.42 0.30 -0.120 2.00 3.0 0.10 0.78827 5 m 2 HD 18361 4900 2.60 0.01 0.49 0.36
-0.130 2.40 4.0 0.02 0.06940 5 m 2 HD 18418 4845 2.40 -0.29 0.12 0.67 0.550
3.00 4.0 0.80 0.22111 5 s 3 HD 20394 5100 2.90 -0.22 1.07 1.43 0.360 2.30 2.5
1.18 0.04319 5 s 2 HD 20644 4115 1.20 -0.12 - 0.59 - - 1.5 1.49 0.17501 4 m 3
HD 21682 5200 2.80 -0.48 0.52 0.88 0.360 2.40 2.5 0.02 0.94319 5 s 2 HD 21989
4400 1.80 -0.14 0.54 0.68 0.140 1.60 2.0 0.98 0.35407 5 s 2 HD 22285 4900 2.30
-0.60 0.97 1.32 0.350 1.30 2.5 1.15 0.33086 5 s 2 HD 22589 5400 3.30 -0.27
0.91 0.59 -0.320 1.30 2.5 1.77 0.84988 14 m 1 HD 22772 4800 2.40 -0.17 0.84
0.99 0.150 1.10 3.0 1.12 0.01119 5 s 2 HD 24035 4750 2.20 -0.51 1.75 1.61
-0.140 0.80 - - - - s 5 HD 26886 5000 2.50 -0.30 0.47 0.72 0.250 2.30 3.0 0.01
0.71536 5 s 2 HD 27271 5022 2.90 -0.07 0.87 0.77 -0.100 2.60 3.0 11.25 0.00100
12 s 1, 4 HD 28159 3900 2.00 -0.50 0.25 0.40 0.140 0.80 5.0 12.82 0.10815 12 m
4 HD 29370 4800 2.10 -0.25 0.77 1.21 0.440 1.80 2.0 1.70 0.18502 5 s 2 HD
29685 4900 2.70 -0.07 0.57 0.66 0.090 1.40 3.0 1.87 0.16276 5 s 2 HD 30240
5100 2.70 0.02 0.70 0.72 0.020 2.80 3.0 1.60 0.03818 5 s 2 HD 30554 4800 2.50
-0.12 0.69 0.92 0.230 1.50 2.0 1.26 0.10176 5 s 2 HD 31308 4865 2.80 0.16 -
0.31 - 3.00 4.0 1.93 0.49622 4 m 3 HD 31487 4960 3.10 -0.04 1.28 1.58 0.300
2.60 - - - 11 s 4 HD 31812 5100 2.60 -0.07 0.66 0.53 -0.130 2.50 3.0 0.52
0.20328 5 m 2 HD 32712 4550 2.50 -0.25 0.63 1.52 0.890 1.00 2.5 15.82 0.03205
11 s 5 References: 1. Allen & Barbuy (2006), 2. de Castro et al. (2016). 3.
Yang et al. (2016), 4. Karinkuzhi et al. (2018), 5. Shejeelammal et al.
(2020), 6. This work

-continued Star Name Teff logg [Fe/H] [ls/Fe] [hs/Fe] [hsls] MBa M${}^{ini}_{AGB}$ $\chi^{2}$ dil N Type Ref (K) (cgs) (M⊙) (M⊙) HD 32901 4400 1.60 -0.44 0.29 0.92 0.630 0.80 3.0 0.52 0.63315 5 s 2 HD 33709 5000 2.10 -0.20 0.36 0.45 0.090 4.00 - - - 5 m 2 HD 35993 5100 2.90 -0.05 0.91 1.22 0.310 2.40 - - - 5 s 2 HD 36650 4880 2.40 -0.02 0.62 0.84 0.210 1.90 3.0 2.61 0.18718 5 s 5 HD 38488 4400 2.00 0.05 0.83 0.98 0.140 2.30 - - - 5 s 2 HD 39778 5000 2.50 -0.12 0.78 0.98 0.200 2.40 - - - 5 s 2 HD 40430 4900 2.50 -0.23 0.67 0.85 0.180 2.20 3.0 0.14 0.48739 5 s 2 HD 41701 5000 2.60 0.02 0.35 0.39 0.040 2.60 4.0 0.53 0.14309 5 m 2 HD 42700 4800 2.20 -0.25 0.09 0.22 0.130 1.70 6.0 0.07 0.09376 5 m 2 HD 43232 4386 1.40 -0.03 0.12 0.46 0.340 4.00 - - - 5 m 3 HD 43389 4000 2.00 -0.38 0.50 1.49 0.980 - 2.0 10.18 0.18226 12 s 2, 4 HD 45483 4800 2.20 -0.14 0.65 0.61 -0.040 1.80 2.0 0.32 0.35138 5 s 2 HD 46407 4854 2.20 -0.36 1.31 1.58 0.280 1.40 - - - 11 s 4 HD 48565 5860 4.00 -0.62 1.06 1.40 0.340 1.30 2.5 1.50 0.41230 14 s 1 HD 48814 4800 2.30 -0.07 0.39 0.28 -0.110 2.00 4.0 0.18 0.22345 5 m 2 HD 49017 5100 2.80 0.02 0.09 0.35 0.260 2.80 4.0 1.17 0.45773 5 m 2 HD 49641 4400 1.50 -0.30 0.71 1.29 0.580 2.20 3.0 0.15 0.08592 7 s 2, 3 HD 49661 5000 2.40 -0.13 0.15 0.33 0.180 2.40 4.0 0.31 0.29285 5 m 2 HD 49778 5000 2.30 -0.22 0.16 0.37 0.210 4.50 5.0 0.04 0.06051 5 m 2 HD 50075 4900 2.50 -0.16 0.63 0.97 0.340 2.40 - - - 5 s 2 HD 50082 4789 2.40 -0.32 1.06 1.50 0.440 1.40 2.5 3.55 0.13084 12 s 4 HD 50843 4700 2.30 -0.31 0.21 0.65 0.440 0.90 4.0 0.28 0.17401 5 s 2 HD 51959 5000 3.20 -0.10 0.69 0.89 0.200 1.20 2.0 1.05 0.12993 5 s 2 HD 53199 5000 2.30 -0.23 0.69 0.92 0.230 2.10 - - - 6 s 2 HD 58121 4600 1.80 -0.01 0.33 0.44 0.100 2.50 4.0 1.66 0.07038 7 m 2, 3 HD 58368 5000 2.60 0.04 0.72 0.91 0.190 2.50 - - - 5 s 2, 3 HD 59852 5000 2.20 -0.22 0.34 0.37 0.030 2.60 - - - 5 m 2 HD 60197 3800 2.00 -0.60 0.96 1.21 0.240 - 2.5 9.78 0.04846 12 s 4 HD 61332 4700 2.10 0.07 0.41 0.49 0.080 2.50 4.0 0.68 0.01184 5 m 2 HD 62017 5000 1.80 -0.32 0.72 0.80 0.080 2.80 3.0 0.64 0.53949 5 s 2 HD 64425 4900 2.40 0.06 0.86 1.06 0.200 2.10 - - - 5 s 2 HD 66216 4588 2.40 0.23 - 0.31 - - 4.0 0.57 0.49628 4 m 3 HD 66291 4600 1.50 -0.31 0.66 0.87 0.220 - 2.5 0.51 0.75217 5 s 2 HD 67036 4300 1.50 -0.41 0.92 1.24 0.320 1.10 2.5 2.42 0.51454 5 s 2 HD 71458 4600 2.20 -0.03 0.59 0.77 0.170 2.10 3.0 2.88 0.06749 5 s 2 HD 74950 4200 1.20 -0.21 0.60 0.88 0.280 1.30 2.0 0.87 0.48814 5 s 2 HD 76225 6110 3.80 -0.31 1.17 1.10 -0.070 1.30 2.5 1.10 0.49086 14 s 1 HD 81797 4034 1.20 0.01 0.15 0.50 \- 0 - 4.0 2.80 0.37459 4 m 3 HD 82221 4400 1.60 -0.21 0.84 0.92 0.080 1.30 3.0 0.46 0.24681 5 s 2 HD 83548 5000 2.40 0.03 0.70 0.77 0.070 3.50 - - - 5 s 2 HD 84610 4900 2.50 0.00 0.59 0.59 -0.000 2.30 3.0 1.48 0.19780 5 m 2 HD 84678 4600 1.70 -0.13 1.15 1.77 0.620 1.90 - - - 5 s 2 HD 87080 5460 3.70 -0.44 1.15 1.63 0.480 1.30 2.0 1.08 0.16062 14 s 1 HD 88035 4900 2.40 -0.10 0.83 1.31 0.480 2.60 - - - 5 s 2 HD 88495 4900 3.00 -0.11 0.67 0.66 -0.010 1.00 2.0 0.21 0.30187 5 s 2 HD 88562 4000 2.00 -0.53 0.90 1.21 0.300 0.80 2.5 6.92 0.53838 12 s 4 HD 88927 4600 2.30 0.02 0.41 0.24 -0.160 1.20 4.0 0.12 0.23975 5 m 2 HD 89175 4900 2.10 -0.55 1.03 1.88 0.850 1.30 2.5 2.06 0.04801 5 s 2 HD 89638 4900 2.40 -0.19 0.46 0.68 0.220 1.80 2.0 1.04 0.40945 5 s 2 HD 89948 6010 4.30 -0.30 1.01 0.82 -0.190 0.90 2.5 1.97 0.78790 14 s 1 HD 90127 4600 2.20 -0.40 0.70 0.93 0.230 1.00 2.5 0.88 0.82555 7 s 2, 3 HD 90167 5000 2.60 -0.04 0.51 0.31 -0.200 2.60 4.0 0.05 0.09771 5 m 2 HD 91208 5100 3.00 0.05 0.77 0.77 -0.000 2.40 2.5 1.72 0.01872 5 s 2 HD 91979 4900 2.70 -0.11 0.73 0.92 0.180 1.20 2.0 0.90 0.08348 5 s 2 HD 92545 6210 4.00 -0.12 0.69 0.69 0.010 1.20 2.0 0.69 0.29535 14 s 1 HD 92626 4800 2.30 -0.15 1.10 1.98 0.880 2.50 - - - 5 s 2 HD 94518 5700 3.90 -0.55 0.66 0.86 0.200 0.80 1.5 9.91 0.21671 9 s 5