# A MOLECULAR LINE OBSERVATION TOWARD MASSIVE CLUMPS ASSOCIATED WITH INFRARED
DARK CLOUDS

Takeshi Sakai11affiliation: Nobeyama Radio Observatory, Minamimaki,
Minamisaku, Nagano 384-1305, Japan. , Nami Sakai22affiliation: Department of
Physics, Graduate School of Science, The University of Tokyo, Tokyo 113-0033,
Japan. , Kazuhisa Kamegai33affiliation: Institute of Astronomy, The University
of Tokyo, Osawa, Mitaka, Tokyo 181-0015, Japan , Tomoya Hirota44affiliation:
National Astronomical Observatory of Japan, Osawa, Mitaka, Tokyo 181-8588,
Japan. , Nobuyuki Yamaguchi11affiliation: Nobeyama Radio Observatory,
Minamimaki, Minamisaku, Nagano 384-1305, Japan. , Shoichi Shiba22affiliation:
Department of Physics, Graduate School of Science, The University of Tokyo,
Tokyo 113-0033, Japan. and Satoshi Yamamoto22affiliation: Department of
Physics, Graduate School of Science, The University of Tokyo, Tokyo 113-0033,
Japan.

###### Abstract

We have surveyed the N2H+ $J$=1–0, HC3N $J$=5–4, CCS $J_{N}$=$4_{3}$–$3_{2}$,
NH3 ($J$, $K$) = (1, 1), (2, 2), (3, 3), and CH3OH $J$=7–6 lines toward the 55
massive clumps associated with infrared dark clouds by using the Nobeyama
Radio Observatory 45 m telescope and the Atacama Submillimeter Telescope
Experiment 10 m telescope. The N2H+, HC3N, and NH3 lines are detected toward
most of the objects. On the other hand, the CCS emission is detected toward
none of the objects. The [CCS]/[N2H+] ratios are found to be mostly lower than
unity even in the Spitzer 24 $\mu$m dark objects. This suggests that most of
the massive clumps are chemically more evolved than the low-mass starless
cores. The CH3OH emission is detected toward 18 out of 55 objects. All the
CH3OH-detected objects are associated with the Spitzer 24 $\mu$m sources,
suggesting that star formation has already started in all the CH3OH-detected
objects. The velocity widths of the CH3OH $J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ and
$7_{-1}$–$6_{-1}$ $E$ lines are broader than those of N2H+ $J$=1–0. The CH3OH
$J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ and $7_{-1}$–$6_{-1}$ $E$ lines tend to have
broader linewidth in the MSX dark objects than in the others, the former being
younger or less luminous than the latter. The origin of the broad emission is
discussed in terms of the interaction between an outflow and an ambient cloud.

ISM: clouds — ISM: molecule — star: formation

##  1 Introduction

Infrared dark clouds (IRDCs) are extinction features against the background
mid-IR emission (e.g. Simon et al. 2006), which were recognized by the
observations with the mid-infrared satellites such as ISO and MSX (Pérault et
al. 1996; Egan et al. 1998). Mapping observations of the mm and sub-mm
continuum emissions (Carey et al. 1998; Beuther et al. 2002; Rathborne et al.
2006) revealed that massive clumps are associated with several IRDCs. Although
such massive clumps have a similar mass to the clumps with ongoing high-mass
star formation, they are less active. The gas kinetic temperature of IRDCs is
as low as 10–20 K (Carey et al. 1998, Teyssier et al. 2002, Pillai et al.
2006b). Therefore, massive clumps in IRDCs are thought to be starless or at
least in a very early stage of high-mass star formation.

Recently, evidences of high-mass star formation were found in several massive
clumps associated with IRDCs. Rathborne et al. (2005) found luminous sources
(9,000$\sim$32,000 $L_{\odot}$) in massive clumps of IRDC G034.43+00.24, which
are recognized as high-mass protostars ($\sim$ 10 $M_{\odot}$). Rathborne et
al. (2007) also reported that a high-mass protostar ($>$ 8 $M_{\odot}$) is
associated with a massive clump in IRDC G024.33+00.11 on the basis of their
high angular resolution mm-wave observation. Beuther et al. (2005b) and
Beuther & Steinacker (2007) found a protostar in IRDC 18223-3 using the
Spitzer and the Plateau de Bure data, which would grow up to a high-mass star
at the end of its formation process. In addition to these, indirect evidences
of high-mass star formation, such as the CH3OH masers, are found in some IRDCs
(Ellingsen 2006; Purcell et al. 2006).

As mentioned above, IRDCs are good targets for studies on high-mass star
formation. But little attention has been paid for their chemical compositions,
although it would be useful to understand the evolutionary stages of IRDCs.
Since binary chemical reactions, such as neutral-neutral and ion-neutral
reactions, are responsible for chemical processes in the deep inside of
molecular clumps, the chemical composition changes slowly toward chemical
equilibrium with a time scale of $\sim 10^{6}$ yr. This time scale is
comparable with the dynamical time scale of molecular cloud clumps. Therefore,
chemical composition would reflect evolutionary stages of clumps. For example,
carbon-chain molecules, such as CCS and HC3N, are abundant in the early stage
of chemical evolution, while N2H+ and NH3 are abundant in the late stage (e.g.
Lee et al. 1996). Furthermore, carbon-chain molecules suffer the great effect
from depletion, whereas N2H+ and NH3 are less affected by depletion. When CO,
a major destroyer of N2H+, is depleted, N2H+ can be abundant in dense parts.
Since NH3 is produced from N2, NH3 can also be abundant (Aikawa et al. 2001,
2005; Bergin & Tafalla 2007). Thus, we can investigate the evolutionary stages
of clumps from the ratios between carbon-chain molecules and N2H+ or NH3.

This method has been established in low-mass star forming regions. Suzuki et
al. (1992) and Benson et al. (1998) surveyed the carbon-chain molecule toward
several low-mass cores, and they found that carbon-chain molecules are more
abundant in starless cores than star-forming cores, whereas NH3 or N2H+ is
more abundant in star-forming cores. In addition, Hirota et al. (2002, 2004)
and Hirota & Yamamoto (2006) found that carbon-chain molecules are very
abundant in several low-mass starless cores. Recently, Sakai et al. (2007)
suggested that this method can also be applied to high-mass star forming
regions. Sakai et al. (2006, 2007) observed the W 3 giant molecular cloud
(GMC) with the CCS $J_{N}$=$4_{3}$–$3_{2}$ and N2H+ $J$=1–0 lines, and found
that the [CCS]/[N2H+] ratio is higher toward a few massive starless cores in
the AFGL 333 cloud than toward the other massive star forming cores in the W 3
GMC. Sakai et al. (2007) proposed that the massive starless cores in the AFGL
333 cloud are novel candidates which will form high- or intermediate-mass
stars, because the CCS emission has hardly been detected in high-mass star-
forming regions (Lai & Crutcher, 2000). Note that definitions of ”core” and
”clump” are described in Sakai et al. (2007).

Chemical composition of clumps would be changed by various activities of newly
born stars. Saturated organic molecules like CH3OH become abundant due to
evaporation of grain mantles. The high excitation lines of CH3OH are therefore
employed as a tracer of hot cores and shocked regions (e.g. Bachiller & Pérez
Gutiérrez 1997).

In this paper, we report a systematic survey of the N2H+ $J$=1–0, CCS
$J_{N}$=$4_{3}$–$3_{2}$, HC3N $J$=5–4, CH3OH $J$=7–6 lines, as well as the NH3
($J$, $K$)=(1, 1), (2, 2) and (3, 3) lines toward massive clumps associated
with IRDCs. Although observations of several molecular lines were carried out
toward massive clumps in the IRDCs (Pillai et al. 2006b, 2007; Leurini et al.
2007; Purcell et al. 2006; Ragan et al. 2006; Beuther & Sridharan 2007), a
systematic survey of molecular lines focusing on chemical composition has been
limited. In this paper, we present chemical compositions and physical
properties of fifty-five nearby massive clumps associated with the IRDCs, and
investigate their evolutionary stages.

##  2 Observations

###  2.1 The Sample

Sridharan et al. (2005) identified the candidates of massive starless clumps
from the objects found with MAMBO by Beuther et al. (2002). Their candidates
involve clumps associated with IRDCs. Rathborne et al. (2006) also observed 38
IRDCs with known kinematic distance by using MAMBO, and listed the positions
of clumps. We prepared a sample of massive clumps associated with IRDCs by use
of these two lists on the basis of the following criteria:

  * 1\. Distance is less than 4.5 kpc.

  * 2\. Mass is larger than 100 $M_{\odot}$.

  * 3\. Galactic longitude is less than 34.5 degree.

In addition to these, we also involved the massive clumps located near the
clumps listed by Sridharan et al. (2005). Their masses are calculated from the
data by Beuther et al. (2002), where the revised equation by Beuther et al.
(2005) is employed. Finally, the sample consists of 55 objects, as listed in
Table A MOLECULAR LINE OBSERVATION TOWARD MASSIVE CLUMPS ASSOCIATED WITH
INFRARED DARK CLOUDS. In the course of this study, 15 objects are eventually
found to have the different LSR velocity from those listed by Rathborne et al.
(2006). As the result, such objects do not satisfy the above criteria.

We investigated whether the observed objects are associated with point-like
sources or extinction features in the MSX 8 $\mu$m data. Then, 12 objects are
found to be associated with the MSX 8 $\mu$m sources, and 26 objects to be
associated with extinction features. We call an object with an MSX 8 $\mu$m
extinction feature as an MSX dark object. In the archival Spitzer 24 $\mu$m
data, we also inspected whether the observed objects are associated with
point-like sources or extinction features of 24 $\mu$m. As a result, the 31
objects are found to be associated with the point-like 24 $\mu$m sources. Note
that there are no available Spitzer data for I18151-1208. There are 11 dark
objects in the Spitzer 24 $\mu$m data, which are all MSX 8 $\mu$m dark
objects. These results are summarized in Table A MOLECULAR LINE OBSERVATION
TOWARD MASSIVE CLUMPS ASSOCIATED WITH INFRARED DARK CLOUDS.

###  2.2 NRO 45 m observations

The N2H+ $J$=1–0, CCS $J_{N}$=$4_{3}$–$3_{2}$, HC3N $J$=5–4, NH3 ($J$, $K$) =
(1, 1), (2, 2) and (3, 3) lines (Table A MOLECULAR LINE OBSERVATION TOWARD
MASSIVE CLUMPS ASSOCIATED WITH INFRARED DARK CLOUDS) were observed by using
the Nobeyama Radio Observatory (NRO) 45 m telescope from January to March in
2007. We used the two SIS receivers, S100 for N2H+ and S40 for CCS and HC3N.
The N2H+, CCS, and HC3N lines were simultaneously observed. The half-power
beam width is about $37^{\prime\prime}$ at 45 GHz and about
$18^{\prime\prime}$ at 93 GHz, and the main beam efficiency is 0.75 at 45 GHz
and 0.53 at 93 GHz. The NH3 (1,1), (2,2) and (3, 3) lines were observed with
the HEMT receiver. The half-power beam width is about $73^{\prime\prime}$ at
22 GHz, and the main beam efficiency is 0.81 at 22 GHz. For all the
observations, acousto-optical radiospectrometers were employed as a backend,
each of which has bandwidth and frequency resolution of 40 MHz and 37 kHz,
respectively. The velocity resolutions are 0.50, 0.25, and 0.12 km s-1 at 22
GHz, 45 GHz, and 93 GHz, respectively.

The telescope pointing was checked by observing the nearby SiO maser sources
every 2 hours, and was maintained to be better than $5^{\prime\prime}$. The
line intensities were calibrated by the chopper wheel method. The system noise
temperature was 200–300 K for the N2H+, CCS, and HC3N observations, whereas it
was 100–150 K for the NH3 observation.

All the observations were carried out with the position switching mode. The
emission free regions in the Galactic Ring Survey 13CO $J$=1–0 data (Jackson
et al. 2006) were employed as the OFF positions. The data reduction was
carried out by use of the AIPS-based software package NewStar developed at
NRO.

###  2.3 ASTE observations

The CH3OH $J$=7–6 lines (Table A MOLECULAR LINE OBSERVATION TOWARD MASSIVE
CLUMPS ASSOCIATED WITH INFRARED DARK CLOUDS) were observed with the Atacama
Submillimeter Telescope Experiment (ASTE) 10 m telescope (Ezawa et al. 2004;
Kohno 2005) from September to October in 2006. We also observed the CH3OH
$J_{K}$=$1_{1}$–$0_{0}$ $A^{+}$ and $J_{K}$=$4_{0}$–$3_{-1}$ $E$ lines
simultaneously. The beam size of the ASTE telescope is about 22′′ at 345 GHz.
We used the SIS receiver, SC345, operated in the double-side-band mode. The
backends were autocorrelators, whose band width and resolution each are 512
MHz and 0.5 MHz, respectively. By using three autocorrelators, we covered the
frequency range from 337.9 to 338.8 GHz. The telescope pointing was calibrated
by observing the thermal continuum emission from the Jupiter. The pointing
observation was carried out every observing day, and the pointing accuracy was
maintained within 3′′.

All the observations were performed with the position switching mode. Antenna
temperature was calibrated by the single load chopper-wheel method. The
intensity scale was checked by observing the CH3OH lines toward the NGC 6334
hot core every 0.5–1 hr in order to correct a small variation of the telescope
gain due to the temperature and elevation change. As a result, the relative
error in intensity calibration can be maintained to be less than 9 %. The main
beam efficiency of the ASTE telescope is estimated to be 0.60, although this
includes an uncertainty of 20 %. The data reduction was carried out by use of
the NewStar.

##  3 Results

###  3.1 Detection Rates & Spectra

Table 3 shows the 3$\sigma$ detection rates of the observed lines. The N2H+
$J$=1–0 emission is detected toward 54 out of 55 objects, the HC3N $J$=5–4
emission toward 43 objects, and the NH3 ($J$, $K$) = (1, 1) emission toward
all the 55 objects. On the other hand, the CCS $J_{N}$=$4_{3}$–$3_{2}$
emission is not detected at all. This survey indicates that the CCS emission
is hardly detected in IRDCs, as in the case of high-mass star-forming regions.
This is not a distance effect. If the AFGL 333 clump were located on the
distance of 4.5 kpc, the peak temperature would be 0.29 K. This value is
higher than the upper limits to the CCS peak intensity of all the observed
objects, except for I18306-0835 MM1, MM2, and MM3. Thus, we can detect the CCS
line, if a chemically young massive clump like the AFGL 333 clump would exist
within the distance of 4.5 kpc.

The CH3OH $J$=7–6 emissions are detected toward 18 objects. Although the upper
state energy of the CH3OH $J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ line is as high as
65 K, the line is detected even in the objects without luminous heating
sources seen in the MSX 8 $\mu$m image (MSX dark objects). In contrast, the
Spitzer 24 $\mu$m sources are associated with all the CH3OH-detected objects
except for I18151-1208 MM2, for which there are no available Spitzer data.
Thus, it is likely that all the objects with the CH3OH $J$=$7_{0}$–$6_{0}$
$A^{+}$ emission harbor hot regions.

Figure 1a shows the spectra of N2H+ $J$=1–0, HC3N $J$=5–4, CH3OH
$J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$, and CCS $J_{N}$=$4_{3}$–$3_{2}$ for the
selected objects, whereas Figure 2a shows those of NH3 ($J$, $K$) = (1, 1),
(2, 2) and (3, 3). The spectra in Figures 1a and 2a are ”typical ones” taken
arbitrarily from the spectra of our sample. The observed spectra toward all
the objects are shown in Figures 1b–e and 2b–e, which are available in the
electric edition of the Journal. Note that the observed lines toward
G024.08+00.04 MM2 have two velocity components (52 km s-1 and 114 km s-1). The
N2H+ $J$=1–0 line shows complicated hyperfine splittings due to the nuclear
spin ($I$=1) of the nitrogen nuclei. The observed line shows triplet
structure, where the center and higher velocity components consist of three
hyperfine lines each unresolved due to the velocity width. The velocity width,
optical depth, and excitation temperature of N2H+ are derived by fitting the
observed spectrum pattern to a multi Gaussian function (see Appendix B in
Sakai et al. 2006). The results are given in Table 4. We fit the spectra of
the HC3N and CH3OH lines to a single Gaussian function, and these results are
summarized in Tables 5 and 6, respectively. We represent the upper limits to
peak temperature and integrated intensity for the non-detected lines in the
tables. The upper limits to peak temperature for the non-detected lines are a
3$\sigma$ value at the velocity resolution of one channel width. The upper
limits to integrated intensity for the non-detected lines are derived by using
the following equation; $3T_{\rm rms}\sqrt{10({\rm kms^{-1}})\Delta V_{\rm
res}}$, where $\Delta V_{\rm res}$ is a channel width in km s-1, and $T_{\rm
rms}$ is a rms noise level at the velocity resolution of $\Delta V_{\rm res}$.

As for the NH3 (1, 1) line, five hyperfine components are fitted to the single
Gaussian each, and the parameters of the main hyperfine components are listed
in Table 7. On the other hand, the NH3 (2, 2) and (3, 3) lines appear as a
single line without hyperfine structure, and hence, they are fitted to a
single Gaussian function each (Tables 8 and 9). Note that the NH3 (1, 1) and
(2, 2) lines show a double-peak feature in G024.33+00.11 MM3 and MM9. Since
the double peak structure is seen even in the weak hyperfine components, it
seems to be a velocity structure. Then, we fit the spectra to a double
Gaussian function. The parameters for each peak are listed in Tables 7 and 8.

As mentioned earlier, we found that the LSR velocities of 15 objects including
G024.33+00.11 are much different from the values in the lists of Rathborne et
al. (2006). This is because they estimated the systemic velocity of the
objects from the 13CO $J$=1–0 line. The critical density of N2H+ $J$=1–0 is
much higher than that of 13CO $J$=1–0, and hence, the N2H+ $J$=1–0 emission
well traces the dense clumps. We re-evaluate the kinematic distance of the
dense clumps from the LSR velocity of the N2H+ or NH3 lines for all the
observed objects by using the rotation curve obtained by Clemens (1985) with
($\Theta_{0}$, $R_{0}$) = (220 km s-1, 8.5 kpc). The derived distances are
listed in Table 4.

Figure 3 shows the spectra covering the CH3OH $J_{K}$=$7_{K}$–$6_{K}$
transitions toward the CH3OH-detected objects. Two strong lines are seen
around 338.4 GHz; these are the $J_{K}$=$7_{-1}$–$6_{-1}$ $E$ and
$J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ lines. In addition, higher excitation lines
($7_{0}$–$6_{0}$ $E$ and $7_{\pm 2}$–$6_{\pm 2}$ $E$) are seen toward most of
the sources. The CH3OH $J_{K}$=$1_{1}$–$0_{0}$ $A^{+}$ and
$J_{K}$=$4_{0}$–$3_{-1}$ $E$ lines from the other side band are also observed.
Although these two lines are lower-$J$ lines, the intensities of these lines
are generally lower than those of the $J_{K}$=$7_{0}$–$6_{0}$ line because of
their lower line strength. Therefore, the two lower-$J$ CH3OH lines are not
detected toward the objects without CH3OH $J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$
emission. The strongest CH3OH source is G034.43+00.24 MM1, where even the
$J_{K}$=$7_{3}$–$6_{3}$ lines ($E_{u}$ = 112–127 K) are detected. The H2CS
101,10–91,9 line ($E_{u}$ = 102 K) is detected toward three objects,
G024.33+00.11 MM1, G034.43+00.24 MM1, and I18182-1433 MM1, which seem to
contain hot core activities. In fact, Rathborne et al. (2007) reported the
detection of many molecular lines, such as HCOOCH3 and CH3CH2CN, toward
G024.33+00.11 MM1. Since large organic molecules are thought to be formed from
molecules evaporated from dust grains, such as C2H2, HCN, and CH3OH, in the
hot gas phase (e.g. Nomura & Millar, 2004), the detections of HCOOCH3 and
CH3CH2CN definitively indicate the hot core activity.

###  3.2 Integrated Intensities

In Figure 4, we plot the integrated intensities of a few observed lines
against the peak flux of the 1.2 mm continuum, $F_{1.2}$, reported by Beuther
et al. (2002) and Rathborne et al. (2006). We plot only the values of the
objects with $D$ $\leq$ 4.5 kpc. The mm-wave dust continuum emission is
optically thin in general, and it is a good tracer of column density of a
dense region. A correlation between the N2H+ $J$=1–0 emission and the dust
continuum emission was suggested in several regions (Caselli et al. 1999,
2002a; Bergin et al. 2001; Sakai et al. 2007), although it was also reported
that the N2H+ emission does not always trace the structures by dust continuum
emission in very active star forming regions, such as Orion KL (Ungerechts et
al. 1998). In IRDCs, the N2H+ emission is correlated with the 1.2 mm peak
flux, as shown in Figure 4, confirming that the N2H+ emission well traces the
column density of a dense regions. The HC3N integrated intensity is also
roughly correlated with the 1.2 mm peak flux, suggesting that the HC3N
emission also comes from a dense region, as well as the N2H+ emission. The
CH3OH $J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ line is only detected toward the objects
where $F_{1.2}$ is higher than 100 mJy. By using the relation reported by
Beuther et al. (2005a), $F_{1.2}$ of 100 mJy corresponds to $A_{V}$ of 49, 68,
and 114 at $T_{k}$ of 40, 30, and 20 K, respectively. Furthermore, all the
objects with $F_{1.2}$ $>$ 130 mJy are the Spitzer sources. Hence, the
appearance of the CH3OH $J$=7–6 emission is related to the star formation
activity.

A marginal correlation can be seen between the NH3 integrated intensities and
the 1.2 mm peak flux. The NH3 integrated intensities are scattered even at the
low $F_{1.2}$ values, probably because the NH3 emission traces less dense gas
due to its lower critical density ($\sim$ 103 cm-3), and also because the beam
size of the NH3 observation (73′′) is larger than those of the other
observations (18′′–37′′).

##  4 Discussions

###  4.1 Temperatures

We derive the NH3 rotation temperature, $T_{\rm rot}$(NH3), from the NH3 (1,
1) and (2, 2) lines by using the method presented by Ho & Townes (1983) and Li
et al. (2003). We first evaluate the optical depth of the NH3 (1, 1) line from
the peak intensity ratio of the main and satellite hyperfine components. Then
we calculate the rotation temperature from the peak intensity ratio of the
main hyperfine components of the (1, 1) and (2, 2) lines considering the
optical depth of the (1, 1) line obtained above. The derived $T_{\rm
rot}$(NH3) values are listed in Table 10. A range of $T_{\rm rot}$(NH3) is
from 10.3 to 20.8 K with the median of 14–16 K. This is higher than the
corresponding values of $T_{\rm rot}$(NH3) reported for dark clouds (10–15 K;
Benson & Myers, 1989).

Figure 5 represents a histogram of $T_{\rm rot}$(NH3) for the objects with $D$
$\leq$ 4.5 kpc. Figure 5 shows that $T_{\rm rot}$(NH3) for the MSX sources
tends to be higher than that for the MSX dark objects. This confirms that the
emitting regions are associated with the MSX sources. The $T_{\rm rot}$(NH3)
values of the MSX and Spitzer dark objects tend to be lower than those of the
other objects. The average $T_{\rm rot}$(NH3) value of the MSX and Spitzer
dark objects is 13.9$\pm$1.5 K, which is comparable to that for the other
samples of the MSX-dark IRDCs (13.9 K: Pillai et al. 2006b; 15.3 K: Sridharan
et al. 2005), but is lower than that for the high-mass protostellar objects
(22.5 K: Sridharan et al. 2002).

The rotation temperatures of CH3OH, $T_{\rm rot}$(CH3OH), are derived by using
the rotation diagram method (e.g. Turner 1991) under the assumption of local
thermodynamic equilibrium (LTE). Since several E type lines are detected in
many objects (Figure 3), we derive the rotation temperature from them. The
results are listed in Table 11. The derived $T_{\rm rot}$(CH3OH) values range
from 7 to 12 K. The range is lower than that for the high-mass star forming
cores (24–203 K reported by van der Tak et al. (2000b), if we exclude one
exception of GL 7009S (8 K)). The average value of $T_{\rm rot}$(CH3OH) in the
MSX dark objects is 8.0$\pm$0.9 K, which seems to be slightly lower than that
of the MSX sources (10$\pm$2 K). Although the upper state energy of the CH3OH
$J$=$7_{-1}$–$6_{-1}$ $E$ line is 70 K, the derived temperatures are less than
12 K, which are even lower than $T_{\rm rot}$(NH3). This may suggest that the
rotational levels of CH3OH are not thermalized to the gas kinetic temperature.
Leurini et al. (2007) modeled the CH3OH emission toward several IRDCs, and
they derived the gas kinetic temperatures for an extended component, an
outflow, and a core to be 24$\pm$7, 15$\pm$5, and 47$\pm$9 K, respectively.
The $T_{\rm rot}$(CH3OH) values derived in the present study are lower than
their values, implying that the CH3OH lines are subthermally excited.

###  4.2 Column Densities

We derive the column densities of the observed molecules. For simplicity, we
assume the LTE condition for all the molecules. As for N2H+, we derive the
column density by assuming that the excitation temperature is equal to the
rotation temperature of NH3, and the lines are optically thin. This can be
justified, because $\Delta V$(N2H+) is similar to $\Delta V$(NH3), as
mentioned in the next section. The derived column densities are listed in
Table 10. In the case of G034.43+00.24 MM1, a change in $T_{\rm ex}$ by $\pm$1
K results in a change in the derived column density by $\pm$4 %. Most of the
N2H+ column densities are found to be larger than 1$\times$1013 cm-2. This is
higher than a typical value found in low mass cores, which is several times
1012 cm-2 (Benson et al. 1998; Caselli et al. 2002b).

The upper limit to the CCS column density is derived by assuming the optically
thin condition. The rotation temperature of NH3 is employed as the excitation
temperature. The derived upper limits are listed in Table 10. They are found
to be lower than 7$\times$1012 cm-2 for all the objects. These are lower than
the CCS column densities of some low-mass starless cores in the dark clouds,
typically a few times 1013 cm-2 (Suzuki et al. 1992; Benson et al. 1998), and
are also lower than the CCS column density of the massive clump in the AFGL
333 cloud, which is (1.2–3.0)$\times$1013 cm-2 (Sakai et al. 2007). Table 10
lists the upper limit to the [CCS]/[N2H+] ratio. Most of the ratios are lower
than 1 even in the Spitzer dark objects, whereas the corresponding ratio is as
high as 2.6–3.2 for some low-mass starless cores (Benson et al. 1998). Since
we use the [CCS]/[N2H+] ratio to discuss the chemical evolution, the distance
effect would be cancelled. It is therefore suggested that the massive clumps
associated with the IRDCs are chemically evolved than low mass starless cores.
This survey demonstrates that the AFGL 333 clump could be a rare case of a
chemically young massive clump.

The HC3N column density is evaluated by assuming the optically thin condition,
where the excitation temperature is assumed to be equal to $T_{\rm rot}$(NH3).
In the case of G034.43+00.24 MM1, a change in $T_{\rm ex}$ by $\pm$1 K results
in a change in the derived column density by $\pm$3 %. In contrast to CCS, the
derived HC3N column densities (Table 10) are comparable to those for the low-
mass starless cores, $\sim$1013-14 cm-2(Suzuki et al. 1992), even in the
objects with MSX sources, probably because HC3N is less sensitive to chemical
evolution than CCS. In addition, HC3N could also be formed in a hot gas. In
fact, strong HC3N emission is detected toward hot core sources like Orion KL
(Ungerechts et al. 1998).

The NH3 column density is derived from the optical depth and rotation
temperature (Section 4.1). The derived column densities are listed in Table
10. The NH3 column densities (a few times 1015 cm-2) are higher than those of
the low mass cores, $\sim$1014-15 cm-2 (Suzuki et al. 1992), and are
comparable to those of the IRDCs observed by Pillai et al. (2006b). The
$N$(CCS)/$N$(NH3) ratios are found to be lower than 0.007 for most cases,
which are lower than those in some low-mass dark cloud cores ($>$0.01) (Suzuki
et al. 1992). Along with the results of the $N$(CCS)/$N$(N2H+) ratio, this
further supports that the observed IRDCs are chemically evolved.

We derive the CH3OH column density from the integrated intensity of the CH3OH
$J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ line. In this calculation, $T_{\rm
rot}$(CH3OH) is not used as the excitation temperature, because the rotational
levels of CH3OH are not thermalized as mentioned before. $T_{\rm rot}$(CH3OH)
is an effective temperature determined by the population difference between
the different $K$ ladders, and does not always represent the excitation
temperature of the $7_{0}$–$6_{0}$ $A^{+}$ line. Therefore, we assume the
excitation temperature ranging from 20 K to 50 K by referring the result by
Leurini et al. (2007). We also estimate the upper limit to the CH3OH column
density for the non-detected objects with adopting the rotation temperature of
20 K. The derived CH3OH column densities ranges from 2.9$\times$1014 to
4.9$\times$1015 cm-2 toward the CH3OH-detected objects, as shown in Table 10.
They are comparable to those in the IRDCs obtained by Leurini et al. (2007),
although they tend to be lower than those in several IRDCs obtained by Beuther
& Sridharan (2007) (1.7$\times$1013–3.7$\times$1014 cm-2). In addition, they
are also comparable to those in the massive star forming regions obtained by
van der Tak et al. (2000b). On the other hand, Maret et al. (2005) reported
that the CH3OH column densities ranges from 5.3$\times$1013 to 8.1$\times$1014
cm-2 in the low-mass star forming regions, NGC 1333, L1448, L1157, and
IRAS16293-2422. Thus, the CH3OH column densities tend to be higher than those
in the low-mass star forming regions.

###  4.3 Velocity Widths & Star Formation

Velocity widths give information about turbulence of clumps including effects
of star formation activity. In Figure 6, we plot the velocity widths of the
HC3N $J$=5–4, CH3OH $J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$, NH3 ($J$, $K$) = (1, 1),
(2, 2) and (3, 3) lines against that of the N2H+ $J$=1–0 line for the objects
with $D$ $\leq$ 4.5 kpc. The velocity widths of the HC3N, NH3 (1, 1) and (2,
2) lines are correlated with that of N2H+, indicating that they come from
almost the same region. On the other hand, the correlation is poor for high
excitation lines such as CH3OH ($J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ and
$7_{-1}$–$6_{-1}$ $E$) and NH3 (3, 3). Since the upper state energies of CH3OH
$J$=$7_{K}$–$6_{K}$ (65 K) is higher than that of N2H+ $J$=1–0 (4 K) and that
of NH3 (3, 3) is as high as 124.5 K, the CH3OH $J$=7–6 and NH3 (3, 3) lines
would trace the denser and hotter region near the protostar. In fact, the
velocity widths of the CH3OH $J$=7–6 and NH3 (3, 3) lines are correlated with
each other (Figure 7). Pillai et al. (2006a) also found that the NH3 (3, 3)
velocity width is larger than the NH3 (1, 1) and (2, 2) velocity widths toward
the IRDC, G11.11-0.12. Beuther et al. (2002) reported a similar trend in the
C34S and NH3 velocity widths, where the C34S $J$=2–1 velocity widths are about
1.5 times larger than the NH3 (1, 1) velocity widths. Since the C34S emission
is optically thin and the critical density of C34S is as high as $3\times
10^{5}$ cm-3, it also traces dense regions. Furthermore, CS could be abundant
in the hot gas phase in contrast to N2H+ (e.g. Nomura & Millar 2004). Thus it
is likely that the C34S emission comes from regions close to the newly born
stars, as well as the CH3OH and NH3 (3, 3) emissions.

Figure 8 shows histograms of the velocity width of N2H+ for the MSX dark
objects and the objects with MSX sources. The mean N2H+ velocity width of the
MSX dark objects (2.3 km s-1) is almost comparable to that of the objects with
MSX sources (2.5 km s-1). These values are also comparable to that of the
high-mass star forming regions observed by Pirogov et al. (2003; 2.4 km s-1).
The histogram shapes are also similar to each other. Since the N2H+ emission
arises from the whole clump, it is not sensitive to the star formation
activities. The mean N2H+ velocity widths of the MSX and Spitzer dark objects
(2.1 km s-1) are significantly larger than those of the low-mass starless
cores ($\sim$0.5 km s-1) (Benson et al. 1998), and are also larger than those
of the cores in a giant molecular cloud, Orion A (Tatematsu et al. 1993). The
massive clumps associated with the IRDCs seem to be initially turbulent. This
gives an important constraint when one would construct a model of star-
formation processes in IRDCs. For instance, McKee & Tan (2003) argued that
massive stars can form in turbulence-supported cores with a high accretion
rate. Thus, the large velocity widths observed in IRDCs are consistent with
the theoretical prediction, if the IRDCs are birthplaces of high-mass stars.

As shown in Figure 6, the CH3OH $J$=7–6 velocity widths for the MSX dark
objects tend to be broader than those for the objects with MSX sources at a
given N2H+ velocity width. This trend is clear in the case of G034.43+00.24.
Figure 9 shows the Spitzer 24 $\mu$m image toward the G034.43+00.24 region and
the spectra of the CH3OH $J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ and N2H+ $J$=1–0
$F_{1}$=0–1 $F$=1–2 lines toward G034.43+00.24 MM1, MM2 and MM3. In the
Spitzer image, G034.43+00.24 MM3, which is a MSX dark object, is less luminous
than MM1 and MM2. It is known that a ultracompact HII region is associated
with MM2 (Miralles et al. 1994; Shepherd et al. 2007). Thus, MM2 is thought to
be most evolved among three objects, whereas MM3 is thought to be youngest. In
Figure 9, the CH3OH spectrum of G034.43+00.24 MM3 is clearly broader than the
N2H+ spectrum for G034.43+00.24 MM3. On the other hand, the CH3OH velocity
width is comparable to the N2H+ velocity width toward G034.43+00.24 MM1 and
MM2. The CH3OH linewidths toward these two sources are relatively narrower
than that toward MM3.

As seen in Figure 9, the line shape of the CH3OH emission sometimes differs
from the Gaussian shape. It may consist of the broad wing component and the
narrow component. In the present analysis, we fit all the CH3OH spectra with a
single Gaussian, so that the derived velocity widths have to be recognized as
”effective” values for some sources where the line shape is much deviated from
the single Gaussian shape. We employ the single Gaussian fitting rather than
the double Gaussian fitting, because the latter fitting is difficult for most
of the objects due to the limited S/N ratio. Nevertheless, the ”effective”
line width reflects the presence of the broad component, and hence, our
discussion on the basis of the line width would be justified at least
qualitatively.

van der Tak et al. (2000a, 2000b) carried out multi-line observations of
CH3OH, C34S, and C17O toward several massive star-forming regions, and found
that the velocity widths of the CH3OH lines are broader than those of the C34S
and C17O lines for the less luminous objects, whereas they are comparable in
the luminous objects. van der Tak et al. (2000b) argued that shock by the
interaction between an outflow and an ambient cloud is important as the origin
of the gas-phase CH3OH enhancement in low-luminosity objects, while radiation
heating is important in high-luminosity objects. In fact, the broad CH3OH
emission are reported for such an interacting region in several low-mass star
forming regions, including the famous case of L1157, where a clear interaction
between an outflow and an ambient cloud is observed as broad lines of CH3OH,
NH3, and HC3N (Umemoto et al. 1992; Mikami et al. 1992; Bachiller & Pérez
Gutiérrez 1997; Umemoto et al. 1999). In contrast, the N2H+ line is not
detected in the interaction region. Therefore, the CH3OH
$J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ emission would well trace the shocked region
caused by the interaction between an outflow and an ambient cloud in the case
of the MSX dark objects. Furthermore, the broader line width can be seen in
the observed lower-$J$ lines, $J_{K}$=$1_{1}$–$0_{0}$ $A^{+}$ and
$4_{0}$–$4_{-1}$ $E$. This may imply that these CH3OH emissions do not come
from the quiescent and extended regions. To understand the properties of CH3OH
in the quiescent gas, we should observe the lower excitation transitions at
the millimeter-wave region, since the critical density is proportional to
$\nu^{3}$. Our result that the line width of the CH3OH line is broader in the
MSX dark object means that the interaction between an outflow and an ambient
cloud is important in the early stage of high-mass star formation.

##  5 Summary

  * •

We have surveyed the N2H+ $J$=1–0, HC3N $J$=5–4, CCS $J_{N}$=$4_{3}$–$3_{2}$,
CH3OH $J$=7–6, NH3 (J, K) = (1, 1), (2, 2), and (3, 3) lines toward the
massive clumps associated with the IRDCs. The N2H+ $J$=1–0 emission is
detected toward 54 out of 55 objects, the HC3N $J$=5–4 emission toward 43
objects, the NH3 ($J$, $K$) = (1, 1) emission toward all the 55 objects, the
NH3 ($J$, $K$) = (2, 2) emission toward 52 objects, and the NH3 ($J$, $K$) =
(3, 3) emission toward 34 objects. On the other hand, the CCS emission is not
detected at all. The CH3OH $J$=7–6 emission is detected toward 18 out of 55
objects. All the CH3OH detected objects are associated with the Spitzer 24
$\mu$m sources.

  * •

The mean NH3 rotation temperature of the MSX and Spitzer dark objects is 13.9
K, which tends to be lower than that of the objects with those of the MSX
sources (17.9 K).

  * •

The CCS column densities and the [CCS]/[N2H+] and [CCS]/[NH3] ratios in the
massive clumps associated with the IRDCs are lower than those in the low-mass
starless cores. Thus, most of the massive clumps would be more chemically
evolved than the low-mass starless cores. This survey demonstrates that the
massive clump in the AFGL 333 region, which was found by Sakai et al. (2006,
2007), could be very novel.

  * •

The mean N2H+ velocity widths are significantly broader than those of the low-
mass starless cores even in the MSX and Spitzer dark objects, indicating that
massive cores associated with the IRDCs are initially turbulent. This along
with the chemical ages inferred from the [CCS]/[N2H+] ratio would be useful to
constrain a models of star formation processes in IRDCs.

  * •

The velocity widths of the CH3OH $J$=7–6 and NH3 (3, 3) lines are broader than
those of the other lines. This seems to originate from the interaction between
an outflow and an ambient cloud. The CH3OH velocity widths of the MSX dark
objects are larger than those of the objects with MSX sources. This suggests
that outflow interaction plays an important role in production of the gas
phase CH3OH in the early stage of high-mass star formation.

We are grateful to the NRO staff for excellent support in the 45 m
observations. We would like to thank the members of the ASTE team for
supporting the ASTE observations. The 45 m radio telescope is operated by
Nobeyama Radio Observatory, a branch of National Astronomical Observatory of
Japan. The ASTE project is driven by Nobeyama Radio Observatory, a branch of
National Astronomical Observatory of Japan, in collaboration with University
of Chile, and Japanese institutes including University of Tokyo, Nagoya
University, Osaka Prefecture University, Ibaraki University, and Kobe
University.

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Figure 1: Spectra of the N2H+ $J$=1–0, HC3N $J$=5–4, CH3OH
$J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$, and CCS $J_{N}$=$4_{3}$–$3_{2}$ lines toward
the selected 9 objects (a) and all the other objects (b–e). For clarity, the
spectra, except for N2H+, are offset from zero. In Figure 1a, the intensities
for the spectra toward G034.43+00.24 MM2 and MM3 are divided by 2. Figures
1b–e are available in the electric edition of the journal.

Figure 1b: Continued.

Figure 1c: Continued.

Figure 1d: Continued.

Figure 1e: Continued.

Figure 2: Spectra of the NH3 ($J$, $K$) = (1, 1), (2, 2), and (3, 3) lines
toward the selected 9 objects (a) and all the other objects (b–e). For
clarity, the spectra, except for the (1, 1) line, are offset from zero.
Figures 2b–e are available in the electric edition of the journal.

Figure 2b: Continued.

Figure 2c: Continued.

Figure 2d: Continued.

Figure 2e: Continued.

Figure 3: Spectra of the CH3OH $J$=7–6 lines.

Figure 4: Correlation plots of the integrated intensities against the 1.2 mm
continuum peak flux. The 1.2 mm continuum data are observed by Beuther et al.
(2002) and Rathborne et al. (2006). The values of the objects with $D$ $\leq$
4.5 kpc are plotted.

Figure 5: Histogram of the NH3 rotation temperature. The objects with $D$
$\leq$ 4.5 kpc are used for the histogram.

Figure 6: Correlation plots of the N2H+ $J$=1–0 velocity width against the
velocity widths of HC3N $J$=5–4, CH3OH $J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$, CH3OH
$J_{K}$=$7_{-1}$–$6_{-1}$ $E$, NH3 ($J$, $K$) = (1, 1), (2, 2) and (3, 3). The
objects with $D$ $\leq$ 4.5 kpc are plotted.

Figure 7: Correlation plots of the velocity width of CH3OH
$J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ against the velocity width of NH3 ($J$, $K$) =
(3, 3). The objects with $D$ $\leq$ 4.5 kpc are plotted.

Figure 8: Histograms of the N2H+ velocity width of the MSX dark objects (top)
and MSX sources (bottom). The objects with $D$ $\leq$ 4.5 kpc are plotted.

Figure 9: Spizter 24 $\mu$m image toward G034.43+00.24 (left), and spectra of
the CH3OH $J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ (black) and N2H+ $J$=1–0 $F_{1}$=0–1
$F$=1–2 lines (gray) toward G034.43+00.24 MM1, MM2 and MM3 (right).

Table 1: Target list.

Source | R. A. | Dec. | MSXaa”D” indicates a dark object, and ”S” indicates an object with point-like sources, whereas ”—” represents an object without point-like sources and dark spots. | Spitzeraa”D” indicates a dark object, and ”S” indicates an object with point-like sources, whereas ”—” represents an object without point-like sources and dark spots. |  $F_{pk}$(1.2 mm) | Reference
---|---|---|---|---|---|---
| (J2000.0) | (J2000.0) | 8 $\mu$m | 24 $\mu$m | [mJy] |
G015.05+00.07 MM1 | 18 17 50.4 | -15 53 38 | D | D | 115 | 1
G015.31-00.16 MM2 | 18 18 50.4 | -15 43 19 | D | S | 39 | 1
G015.31-00.16 MM3 | 18 18 45.3 | -15 41 58 | D | D | 37 | 1
G019.27+00.07 MM1 | 18 25 58.5 | -12 03 59 | D | S | 150 | 1
G019.27+00.07 MM2 | 18 25 52.6 | -12 04 48 | D | S | 89 | 1
G022.35+00.41 MM1 | 18 30 24.4 | -09 10 34 | D | S | 349 | 1
G022.35+00.41 MM2 | 18 30 24.2 | -09 12 44 | S | S | 67 | 1
G022.35+00.41 MM3 | 18 30 38.1 | -09 12 44 | — | — | 53 | 1
G023.60+00.00 MM1 | 18 34 11.6 | -08 19 06 | — | S | 375 | 1
G023.60+00.00 MM2 | 18 34 21.1 | -08 18 07 | D | S | 272 | 1
G023.60+00.00 MM3 | 18 34 10.0 | -08 18 28 | — | — | 81 | 1
G023.60+00.00 MM4 | 18 34 23.0 | -08 18 21 | — | — | 68 | 1
G023.60+00.00 MM7 | 18 34 21.1 | -08 17 11 | D | S | 58 | 1
G024.08+00.04 MM1 | 18 34 57.0 | -07 43 26 | S | S | 219 | 1
G024.08+00.04 MM2 | 18 34 51.1 | -07 45 32 | D | — | 68 | 1
G024.08+00.04 MM3 | 18 35 02.2 | -07 45 25 | D | D | 50 | 1
G024.08+00.04 MM4 | 18 35 02.6 | -07 45 56 | D | D | 48 | 1
G024.33+00.11 MM1 | 18 35 07.9 | -07 35 04 | S | S | 1199 | 1
G024.33+00.11 MM2 | 18 35 34.5 | -07 37 28 | — | — | 117 | 1
G024.33+00.11 MM3 | 18 35 27.9 | -07 36 18 | — | — | 96 | 1
G024.33+00.11 MM4 | 18 35 19.4 | -07 37 17 | D | D | 90 | 1
G024.33+00.11 MM5 | 18 35 33.8 | -07 36 42 | — | — | 79 | 1
G024.33+00.11 MM6 | 18 35 07.7 | -07 34 33 | D | — | 77 | 1
G024.33+00.11 MM8 | 18 35 23.4 | -07 37 21 | — | — | 72 | 1
G024.33+00.11 MM9 | 18 35 26.5 | -07 36 56 | S | S | 66 | 1
G024.33+00.11 MM11 | 18 35 05.1 | -07 35 58 | D | D | 48 | 1
G024.60+00.08 MM1 | 18 35 40.2 | -07 18 37 | — | S | 279 | 1
G024.60+00.08 MM2 | 18 35 35.7 | -07 18 09 | D | S | 230 | 1
G025.04-00.20 MM1 | 18 38 10.2 | -07 02 34 | — | S | 203 | 1
G025.04-00.20 MM2 | 18 38 17.7 | -07 02 51 | D | S | 92 | 1
G025.04-00.20 MM4 | 18 38 13.7 | -07 03 12 | D | D | 82 | 1
G034.43+00.24 MM1 | 18 53 18.0 | 01 25 24 | — | S | 2228 | 1
G034.43+00.24 MM2 | 18 53 18.6 | 01 24 40 | S | S | 964 | 1
G034.43+00.24 MM3 | 18 53 20.4 | 01 28 23 | D | S | 244 | 1
G034.43+00.24 MM4 | 18 53 19.0 | 01 24 08 | — | S | 221 | 1
G034.43+00.24 MM5 | 18 53 19.8 | 01 23 30 | — | — | 122 | 1
G034.43+00.24 MM6 | 18 53 18.6 | 01 27 48 | D | D | 57 | 1
G034.43+00.24 MM8 | 18 53 16.4 | 01 26 20 | D | D | 51 | 1
G034.43+00.24 MM9 | 18 53 18.4 | 01 28 14 | D | D | 50 | 1
I18102-1800 MM1 | 18 13 11.0 | -17 59 59 | — | S | 316 | 2,3,4
I18151-1208 MM1 | 18 17 58.0 | -12 07 27 | S | No data | 672 | 2,3,4
I18151-1208 MM2 | 18 17 50.4 | -12 07 55 | D | No data | 424 | 2,3,4
I18151-1208 MM3 | 18 17 52.2 | -12 06 56 | S | No data | 149 | 2,3,4
I18182-1433 MM1 | 18 21 09.2 | -14 31 57 | S | S | 1303 | 2,3,4
I18182-1433 MM2 | 18 21 14.9 | -14 33 06 | — | S | 100 | 2,3,4
I18223-1243 MM1 | 18 25 10.5 | -12 42 26 | S | S | 328 | 2,3,4
I18223-1243 MM2 | 18 25 09.5 | -12 44 15 | — | S | 124 | 2,3,4
I18223-1243 MM3 | 18 25 08.3 | -12 45 28 | D | S | 205 | 2,3,4
I18223-1243 MM4 | 18 25 07.2 | -12 47 54 | D | S | 52 | 2,3,4
I18306-0835 MM1 | 18 33 24.0 | -08 33 31 | S | S | 731 | 2,3,4
I18306-0835 MM2 | 18 33 17.2 | -08 33 26 | — | S | 212 | 2,3,4
I18306-0835 MM3 | 18 33 32.1 | -08 32 29 | D | D | 103 | 2,3,4
I18337-0743 MM1 | 18 36 41.0 | -07 39 20 | S | S | 485 | 2,3,4
I18337-0743 MM2 | 18 36 27.7 | -07 40 28 | S | S | 180 | 2,3,4
I18337-0743 MM3 | 18 36 18.2 | -07 41 01 | D | S | 110 | 2,3,4

References. — (1) Rathborne et al. (2006); (2) Sridharan et al. (2002); (3)
Beuther et al. (2002); (4) Sridharan et al. (2005).

Table 2: Observed lines.

Species | Transition |  $\nu$(rest) | $\mu^{2}S$ |  $E_{u}$/$k$ | Reference | Telescope
---|---|---|---|---|---|---
|  | [GHz] | [Debye2] | [K] |  |
CCS |  $J_{N}$=$4_{3}$–$3_{2}$ | 45.379033 | 31.3 | 5.4 | 1 | NRO 45 m
HC3N |  $J$=5–4 | 45.490302 | 69.2 | 6.5 | 2 | NRO 45 m
N2H+ |  $J$=1–0 | 93.173777 | 11.6 | 4.47 | 3 | NRO 45 m
NH3 | ($J$, $K$) = (1, 1) | 23.694495 | 3.24 | 23.4 | 4 | NRO 45 m
NH3 | ($J$, $K$) = (2, 2) | 23.722633 | 7.20 | 64.9 | 4 | NRO 45 m
NH3 | ($J$, $K$) = (3, 3) | 23.870129 | 11.3 | 124.5 | 4 | NRO 45 m
CH3OH |  $J_{K}$ = $7_{0}$–$6_{0}$ $E$ | 338.124502 | 5.480 | 77.1 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{-1}$–$6_{-1}$ $E$ | 338.344628 | 5.375 | 69.6 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{0}$–$6_{0}$ $A^{+}$ | 338.408681 | 5.484 | 65.0 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{2}$–$6_{2}$ $A^{-}$ | 338.512762 | 5.059 | 86.4 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{3}$–$6_{3}$ $A^{+}$ | 338.540795 | 4.457 | 114.8 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{3}$–$6_{3}$ $A^{-}$ | 338.543204 | 4.457 | 114.8 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{-3}$–$6_{-3}$ $E$ | 338.559928 | 4.503 | 126.8 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{3}$–$6_{3}$ $E$ | 338.583195 | 4.486 | 111.8 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{1}$–$6_{1}$ $E$ | 338.614999 | 5.508 | 85.1 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{2}$–$6_{2}$ $A^{+}$ | 338.639939 | 5.509 | 102.7 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{2}$–$6_{2}$ $E$ | 338.721630 | 4.980 | 86.3 | 5 | ASTE
CH3OH |  $J_{K}$ = $7_{-2}$–$6_{-2}$ $E$ | 338.722940 | 5.046 | 90.0 | 5 | ASTE
CH3OH |  $J_{K}$ = $4_{0}$–$3_{-1}$ $E$ | 350.687730 | 1.553 | 35.4 | 5 | ASTE
CH3OH |  $J_{K}$ = $1_{1}$–$0_{0}$ $A^{+}$ | 350.905119 | 1.977 | 16.8 | 5 | ASTE

References. — (1) Yamamoto et al. (1990); (2) JPL Catalog
(http://spec.jpl.nasa.gov/) ; (3) Caselli et al. (1995) ; (4) Ho & Townes
(1983) ; (5) Anderson et al. (1990).

Table 3: 3 $\sigma$ detection rates of the observed lines.aaTypical 3 $\sigma$ level in $T_{a}^{*}$ and channel width in velocity are 0.30 K and 0.070 km s-1 for N2H+, 0.22 K and 0.134 km s-1 for HC3N, 0.24 K and 0.134 km s-1 for CCS, 0.28 K and 0.443 km s-1 for CH3OH, and 0.08 K and 0.253 km s-1 for NH3. MSX | Spitzer | N2H+ | HC3N | CCS | CH3OH | NH3 | NH3 | NH3
---|---|---|---|---|---|---|---|---
|  |  $J$=1–0 |  $J$=5–4 |  $J_{N}$=$4_{3}$–$3_{2}$ |  $J$=7–6 | (1, 1) | (2, 2) | (3, 3)
Dark | Dark | 11/11 | 7/11 | 0/11 | 0/11 | 11/11 | 10/11 | 3/11
Dark | Source | 12/12 | 12/12 | 0/12 | 6/12 | 12/12 | 11/12 | 8/12
Dark | Others | 3/3 | 2/3 | 0/3 | 1/3 | 3/3 | 3/3 | 2/3
Source | Source | 12/12 | 9/12 | 0/12 | 6/12 | 12/12 | 11/12 | 9/12
Others | Source | 9/9 | 7/9 | 0/9 | 5/9 | 9/9 | 9/9 | 7/9
Others | Others | 7/8 | 6/8 | 0/8 | 0/8 | 8/8 | 8/8 | 5/8
Total |  | 54/55 | 43/55 | 0/55 | 18/55 | 55/55 | 52/55 | 34/55

Table 4: Line parameters of the N2H+ $J$=1–0 line and distance of each object.aaThe quoted errors denote one standard deviation. Source | $T_{\rm ex}$ | $\tau$ | $V_{LSR}$ | $\Delta V$ |  $\int T_{a}^{*}dV$ bbVelocity range for integration is $\pm 10$ km s-1 centered at the $LSR$ velocity of N2H+ $J$=1–0 or NH3 (1, 1). | Distance ccThe distance is the assumed kinematic distance based on the rotation curve of Clemens (1985).
---|---|---|---|---|---|---
| [K] |  | [km s-1] | [km s-1] | [K km s-1] | [kpc]
G015.05+00.07 MM1 | 5.1 (0.2) | 2.5 (0.4) | 24.73 (0.03) | 2.79 (0.08) | 6.0 (0.1) | 2.5
G015.31-00.16 MM2 | 4.0 (0.2) | 6.9 (2.0) | 31.12 (0.02) | 0.81 (0.07) | 2.3 (0.1) | 3.1
G015.31-00.16 MM3 | 4.0 (0.1) | 11.4 (2.6) | 30.81 (0.02) | 0.62 (0.04) | 2.6 (0.1) | 3.0
G019.27+0.07 MM1 | 15 (1) | 1.1 (0.1) | 26.76 (0.01) | 3.15 (0.03) | 17.7 (0.1) | 2.3
G019.27+0.07 MM2 | 9.0 (0.6) | 1.5 (0.2) | 27.01 (0.02) | 2.62 (0.04) | 9.8 (0.1) | 2.3
G022.35+00.41 MM1 | 5.9 (0.1) | 3.1 (0.3) | 52.73 (0.02) | 2.74 (0.05) | 8.9 (0.1) | 3.7
G022.35+00.41 MM2 | 6 (2) | 1.50 (1.48) | 60.22 (0.02) | 0.83 (0.07) | 1.9 (0.1) | 4.1
G022.35+00.41 MM3 | 5.0 (0.2) | 3.4 (0.5) | 83.97 (0.03) | 2.23 (0.07) | 5.4 (0.1) | 5.3
G023.60+00.00 MM1 | 7.9 (0.5) | 1.5 (0.2) | 106.89 (0.06) | 3.82 (0.07) | 11.8 (0.1) | 6.7
G023.60+00.00 MM2 | 5.8 (0.3) | 2.2 (0.3) | 53.34 (0.03) | 3.03 (0.07) | 7.6 (0.1) | 3.7
G023.60+00.00 MM3 | 8 (3) | 0.7 (0.4) | 105.51 (0.04) | 3.4 (0.1) | 5.8 (0.1) | 6.6
G023.60+00.00 MM4 | 13 (24) | 0.2 (0.6) | 53.87 (0.05) | 2.6 (0.1) | 3.0 (0.1) | 3.7
G023.60+00.00 MM7 | 8 (1) | 1.3 (0.3) | 54.00 (0.05) | 1.90 (0.06) | 6.0 (0.1) | 3.7
G024.08+00.04 MM1 | 49 (26) | 0.21 (0.13) | 113.63 (0.01) | 2.67 (0.03) | 12.8 (0.1) | 7.8
G024.08+00.04 MM2(1) | 9.4 (8.5) | 0.6 (0.9) | 52.08 (0.03) | 1.5 (0.1) | 2.8 (0.1) | 3.6
G024.08+00.04 MM2(2) | 7 (3) | 0.8 (0.7) | 114.45 (0.04) | 2.1 (0.1) | 3.6 (0.1) | 7.8
G024.08+00.04 MM3 | 3.5 (0.1) | 3.5 (1) | 51.86 (0.06) | 2.2 (0.2) | 2.0 (0.1) | 3.6
G024.08+00.04 MM4 | 3.32 (0.04) | 19 (6) | 51.95 (0.03) | 0.85 (0.08) | 1.7 (0.1) | 3.6
G024.33+00.11 MM1 | 7.6 (0.1) | 3.4 (0.2) | 113.76 (0.02) | 3.53 (0.04) | 19.0 (0.1) | 7.7
G024.33+00.11 MM2 | 5.4 (0.3) | 2.3 (0.4) | 118.22 (0.04) | 3.23 (0.09) | 6.8 (0.1) | 7.7
G024.33+00.11 MM3 | 8 (2) | 0.8 (0.3) | 117.78 (0.05) | 4.3 (0.1) | 7.9 (0.1) | 7.7
G024.33+00.11 MM4 | 6 (2) | 0.9 (0.6) | 115.19 (0.07) | 3.6 (0.2) | 4.2 (0.1) | 7.7
G024.33+00.11 MM5 | 4.69 (0.09) | 4.6 (0.5) | 117.26 (0.04) | 3.00 (0.08) | 7.6 (0.1) | 7.7
G024.33+00.11 MM6 | 7 (2) | 0.9 (0.5) | 114.43 (0.04) | 2.97 (0.10) | 4.5 (0.1) | 7.7
G024.33+00.11 MM8 | — | — | — | — | 0.9 (0.1) | 7.7
G024.33+00.11 MM9 | 3.8 (0.2) | 4.2 (1.5) | 119.78 (0.05) | 1.7 (0.2) | 2.7 (0.1) | 7.7
G024.33+00.11 MM11 | 4.3 (0.3) | 2.4 (0.9) | 112.60 (0.05) | 2.18 (0.05) | 3.0 (0.1) | 7.7
G024.60+00.08 MM1 | 5.4 (0.1) | 3.9 (0.3) | 53.14 (0.03) | 3.10 (0.06) | 9.8 (0.1) | 3.6
G024.60+00.08 MM2 | 10 (2) | 1.2 (0.2) | 115.16 (0.01) | 2.37 (0.04) | 9.3 (0.1) | 7.7
G025.04-00.20 MM1 | 11 (1) | 1.1 (0.2) | 64.00 (0.02) | 2.36 (0.05) | 9.8 (0.1) | 4.2
G025.04-00.20 MM2 | 6.5 (0.4) | 2.0 (0.3) | 63.83 (0.03) | 2.77 (0.07) | 8.1 (0.1) | 4.2
G025.04-00.20 MM4 | 6.2 (0.5) | 1.9 (0.4) | 63.69 (0.02) | 2.18 (0.08) | 6.0 (0.1) | 4.1
G034.43+00.24 MM1 | 39 (2) | 0.75 (0.05) | 57.77 (0.05) | 3.15 (0.01) | 40.5 (0.1) | 3.5
G034.43+00.24 MM2 | 29 (2) | 0.67 (0.06) | 57.832 (0.009) | 4.04 (0.02) | 34.2 (0.1) | 3.5
G034.43+00.24 MM3 | 36 (7) | 0.42 (0.09) | 59.686 (0.008) | 2.90 (0.02) | 20.3 (0.1) | 3.6
G034.43+00.24 MM4 | 14.2 (0.5) | 1.5 (0.1) | 57.689 (0.008) | 2.81 (0.02) | 20.8 (0.1) | 3.5
G034.43+00.24 MM5 | 9 (2) | 0.9 (0.3) | 58.12 (0.03) | 2.58 (0.08) | 6.0 (0.1) | 3.5
G034.43+00.24 MM6 | 10 (2) | 0.8 (0.4) | 58.49 (0.02) | 2.07 (0.07) | 5.6 (0.1) | 3.6
G034.43+00.24 MM8 | 6 (1) | 1.1 (0.5) | 57.63 (0.05) | 3.2 (0.1) | 4.5 (0.1) | 3.5
G034.43+00.24 MM9 | 12 (3) | 0.7 (0.3) | 59.00 (0.02) | 2.45 (0.06) | 7.3 (0.1) | 3.6
I18102-1800 MM1 | 9.3 (0.5) | 1.7 (0.2) | 22.36 (0.02) | 3.49 (0.05) | 15.9 (0.1) | 2.7
I18151-1208 MM1 | 13 (2) | 0.8 (0.2) | 33.19 (0.01) | 2.10 (0.04) | 9.8 (0.1) | 2.8
I18151-1208 MM2 | 14 (2) | 0.9 (0.2) | 29.74 (0.02) | 3.09 (0.04) | 14.2 (0.1) | 2.6
I18151-1208 MM3 | 5.7 (0.2) | 4.9 (0.9) | 30.65 (0.01) | 0.87 (0.04) | 4.4 (0.1) | 2.7
I18182-1433 MM1 | 30 (8) | 0.4 (0.1) | 60.00 (0.01) | 3.06 (0.04) | 16.6 (0.1) | 4.6
I18182-1433 MM2 | 5.8 (0.4) | 2.3 (0.4) | 41.10 (0.03) | 2.28 (0.08) | 6.2 (0.1) | 3.6
I18223-1243 MM1 | 14 (1) | 1.2 (0.2) | 45.32 (0.01) | 2.16 (0.03) | 13.4 (0.1) | 3.6
I18223-1243 MM2 | 8.1 (0.7) | 1.3 (0.2) | 45.29 (0.02) | 2.99 (0.06) | 8.7 (0.1) | 3.6
I18223-1243 MM3 | 9.4 (0.3) | 2.2 (0.2) | 45.73 (0.01) | 2.64 (0.03) | 14.5 (0.1) | 3.7
I18223-1243 MM4 | 5.3 (0.3) | 2.4 (0.5) | 45.83 (0.03) | 1.97 (0.07) | 5.0 (0.1) | 3.7
I18306-0835 MM1 | 27 (31) | 0.2 (0.3) | 78.02 (0.03) | 2.81 (0.07) | 7.2 (0.1) | 4.9
I18306-0835 MM2 | 10 (11) | 0.4 (0.6) | 76.67 (0.05) | 2.6 (0.1) | 3.4 (0.1) | 4.9
I18306-0835 MM3 | 5 (2) | 0.95 (1.5) | 53.98 (0.09) | 2.1 (0.3) | 1.6 (0.1) | 3.7
I18337-0743 MM1 | 7.03 (0.08) | 5.9 (0.3) | 58.37 (0.02) | 3.35 (0.04) | 21.5 (0.1) | 3.9
I18337-0743 MM2 | 8 (1) | 1.3 (0.4) | 58.60 (0.03) | 2.71 (0.08) | 6.9 (0.1) | 3.9
I18337-0743 MM3 | 6.7 (0.6) | 1.7 (0.4) | 56.37 (0.03) | 2.44 (0.08) | 6.6 (0.1) | 3.8

Table 5: Line parameters of the HC3N $J$=5–4 and CCS $J_{N}$=$4_{3}$–$3_{2}$ lines.aaThe quoted errors denote one standard deviation. | HC3N |  | CCS
---|---|---|---
Source | $T_{\rm pk}$ | $V_{LSR}$ | $\Delta V$ |  $\int T_{a}^{*}dV$bbVelocity range for integration is $\pm 5$ km s-1 centered at the $LSR$ velocity of N2H+ $J$=1–0 or NH3 (1, 1). |  | $T_{\rm pk}$ |  $\int T_{a}^{*}dV$bbVelocity range for integration is $\pm 5$ km s-1 centered at the $LSR$ velocity of N2H+ $J$=1–0 or NH3 (1, 1).
| [K] | [km s-1] | [km s-1] | [K km s-1] |  | [K] | [K km s-1]
G015.05+00.07 MM1 | 0.25 (0.02) | 24.4 (0.1) | 3.5 (0.3) | 1.05 (0.09) |  |  $<$0.22 |  $<$0.25
G015.31-00.16 MM2 | 0.28 (0.03) | 30.92 (0.08) | 1.4 (0.2) | 0.61 (0.09) |  |  $<$0.24 |  $<$0.28
G015.31-00.16 MM3 |  $<$0.23 | — | — | 0.51 (0.09) |  |  $<$0.25 |  $<$0.29
G019.27+0.07 MM1 | 0.60 (0.02) | 26.39 (0.05) | 3.7 (0.1) | 2.60 (0.07) |  |  $<$0.19 |  $<$0.23
G019.27+0.07 MM2 | 0.64 (0.02) | 27.02 (0.04) | 2.9 (0.1) | 2.35 (0.07) |  |  $<$0.20 |  $<$0.23
G022.35+00.41 MM1 | 0.46 (0.02) | 53.00 (0.07) | 3.6 (0.2) | 1.94 (0.08) |  |  $<$0.20 |  $<$0.23
G022.35+00.41 MM2 |  $<$0.20 | — | — |  $<$0.24 |  |  $<$0.21 |  $<$0.24
G022.35+00.41 MM3 | 0.34 (0.03) | 84.36 (0.06) | 1.6 (0.1) | 0.59 (0.07) |  |  $<$0.19 |  $<$0.22
G023.60+00.00 MM1 | 0.57 (0.02) | 106.7 (0.06) | 3.6 (0.1) | 2.28 (0.08) |  |  $<$0.23 |  $<$0.26
G023.60+00.00 MM2 | 0.81 (0.02) | 53.37 (0.04) | 3.4 (0.1) | 3.35 (0.08) |  |  $<$0.20 |  $<$0.23
G023.60+00.00 MM3 |  $<$0.21 | — | — | 0.41 (0.08) |  |  $<$0.23 |  $<$0.27
G023.60+00.00 MM4 | 0.33 (0.02) | 53.91 (0.07) | 2.3 (0.2) | 0.76 (0.07) |  |  $<$0.21 |  $<$0.25
G023.60+00.00 MM7 | 0.55 (0.02) | 54.08 (0.05) | 2.1 (0.1) | 1.56 (0.08) |  |  $<$0.21 |  $<$0.24
G024.08+00.04 MM1 | 0.30 (0.02) | 113.68 (0.08) | 2.8 (0.2) | 0.89 (0.07) |  |  $<$0.21 |  $<$0.24
G024.08+00.04 MM2(1) | 0.22 (0.03) | 52.18 (0.07) | 0.9 (0.2) | 0.44 (0.07) |  |  $<$0.21 |  $<$0.24
G024.08+00.04 MM2(2) |  $<$0.19 | — | — | 0.38 (0.07) |  |  $<$0.21 |  $<$0.24
G024.08+00.04 MM3 | 0.39 (0.02) | 51.67 (0.04) | 1.6 (0.1) | 0.78 (0.07) |  |  $<$0.24 |  $<$0.28
G024.08+00.04 MM4 | 0.56 (0.03) | 51.90 (0.02) | 1.08 (0.07) | 0.83 (0.07) |  |  $<$0.21 |  $<$0.24
G024.33+00.11 MM1 | 0.71 (0.02) | 113.69 (0.06) | 4.0 (0.1) | 3.22 (0.09) |  |  $<$0.28 |  $<$0.32
G024.33+00.11 MM2 | 0.34 (0.02) | 118.1 (0.1) | 3.4 (0.2) | 1.27 (0.09) |  |  $<$0.25 |  $<$0.29
G024.33+00.11 MM3 | 0.24 (0.02) | 117.2 (0.2) | 5.1 (0.4) | 1.31 (0.09) |  |  $<$0.27 |  $<$0.31
G024.33+00.11 MM4 |  $<$0.23 | — | — | 1.11 (0.09) |  |  $<$0.26 |  $<$0.30
G024.33+00.11 MM5 | 0.34 (0.02) | 117.4 (0.1) | 4.0 (0.3) | 1.48 (0.09) |  |  $<$0.23 |  $<$0.27
G024.33+00.11 MM6 |  $<$0.24 | — | — | 0.73 (0.09) |  |  $<$0.28 |  $<$0.32
G024.33+00.11 MM8 |  $<$0.23 | — | — |  $<$0.27 |  |  $<$0.29 |  $<$0.34
G024.33+00.11 MM9 | 0.21 (0.03) | 119.4 (0.1) | 1.3 (0.2) | 0.50 (0.09) |  |  $<$0.29 |  $<$0.33
G024.33+00.11 MM11 |  $<$0.23 | — | — |  $<$0.27 |  |  $<$0.28 |  $<$0.32
G024.60+00.08 MM1 | 0.63 (0.02) | 53.22 (0.05) | 3.5 (0.1) | 2.59 (0.08) |  |  $<$0.17 |  $<$0.20
G024.60+00.08 MM2 | 0.29 (0.02) | 115.2 (0.1) | 3.0 (0.2) | 1.23 (0.09) |  |  $<$0.28 |  $<$0.32
G025.04-00.20 MM1 | 0.46 (0.02) | 63.67 (0.07) | 3.0 (0.2) | 1.67 (0.09) |  |  $<$0.23 |  $<$0.26
G025.04-00.20 MM2 | 0.46 (0.03) | 63.63 (0.07) | 2.4 (0.2) | 1.21 (0.09) |  |  $<$0.29 |  $<$0.34
G025.04-00.20 MM4 | 0.35 (0.03) | 63.76 (0.08) | 2.0 (0.2) | 0.67 (0.09) |  |  $<$0.23 |  $<$0.27
G034.43+00.24 MM1 | 1.22 (0.02) | 58.04 (0.03) | 3.85 (0.06) | 5.35 (0.06) |  |  $<$0.18 | 0.35 (0.07)
G034.43+00.24 MM2 | 1.10 (0.01) | 57.86 (0.03) | 4.22 (0.06) | 5.09 (0.06) |  |  $<$0.18 | 0.43 (0.07)
G034.43+00.24 MM3 | 0.57 (0.01) | 60.05 (0.07) | 5.8 (0.2) | 3.29 (0.07) |  |  $<$0.18 | 0.41 (0.07)
G034.43+00.24 MM4 | 0.80 (0.02) | 57.50 (0.03) | 3.22 (0.08) | 3.03 (0.07) |  |  $<$0.17 | 0.30 (0.07)
G034.43+00.24 MM5 | 0.31 (0.03) | 57.81 (0.08) | 1.8 (0.2) | 0.67 (0.08) |  |  $<$0.22 | 0.38 (0.08)
G034.43+00.24 MM6 | 0.45 (0.02) | 58.34 (0.06) | 2.5 (0.1) | 1.25 (0.08) |  |  $<$0.23 |  $<$0.26
G034.43+00.24 MM8 | 0.23 (0.02) | 57.7 (0.2) | 4.4 (0.4) | 1.1 (0.08) |  |  $<$0.21 |  $<$0.24
G034.43+00.24 MM9 | 0.50 (0.02) | 58.40 (0.05) | 2.4 (0.1) | 1.31 (0.08) |  |  $<$0.21 |  $<$0.24
I18102-1800 MM1 | 0.83 (0.02) | 21.53 (0.05) | 4.4 (0.1) | 4.14 (0.09) |  |  $<$0.29 |  $<$0.34
I18151-1208 MM1 | 0.53 (0.03) | 33.26 (0.05) | 2.1 (0.1) | 1.39 (0.09) |  |  $<$0.26 |  $<$0.3
I18151-1208 MM2 | 0.25 (0.02) | 30.3 (0.1) | 3.2 (0.3) | 0.93 (0.10) |  |  $<$0.27 |  $<$0.32
I18151-1208 MM3 |  $<$0.24 | — | — | 0.39 (0.09) |  |  $<$0.28 |  $<$0.32
I18182-1433 MM1 | 1.04 (0.03) | 59.86 (0.03) | 2.58 (0.07) | 3.07 (0.09) |  |  $<$0.26 |  $<$0.3
I18182-1433 MM2 |  $<$0.25 | — | — | 0.39 (0.10) |  |  $<$0.26 |  $<$0.3
I18223-1243 MM1 | 0.44 (0.03) | 45.38 (0.06) | 2.1 (0.1) | 1.09 (0.08) |  |  $<$0.22 |  $<$0.25
I18223-1243 MM2 | 0.24 (0.03) | 45.5 (0.1) | 2.1 (0.3) | 0.68 (0.09) |  |  $<$0.21 |  $<$0.25
I18223-1243 MM3 | 0.44 (0.02) | 45.65 (0.07) | 3.2 (0.2) | 1.59 (0.08) |  |  $<$0.24 |  $<$0.28
I18223-1243 MM4 |  $<$0.22 | — | — | 0.71 (0.08) |  |  $<$0.22 |  $<$0.25
I18306-0835 MM1 | 0.39 (0.02) | 78.5 (0.1) | 4.0 (0.2) | 1.7 (0.09) |  |  $<$0.30 |  $<$0.34
I18306-0835 MM2 |  $<$0.25 | — | — | 0.41 (0.10) |  |  $<$0.31 |  $<$0.36
I18306-0835 MM3 |  $<$0.25 | — | — | 0.32 (0.10) |  |  $<$0.31 |  $<$0.36
I18337-0743 MM1 | 1.06 (0.02) | 58.31 (0.04) | 3.51 (0.08) | 4.21 (0.09) |  |  $<$0.22 |  $<$0.26
I18337-0743 MM2 | 0.50 (0.03) | 58.13 (0.06) | 2.3 (0.1) | 1.22 (0.09) |  |  $<$0.24 |  $<$0.28
I18337-0743 MM3 | 0.25 (0.02) | 55.6 (0.2) | 3.7 (0.4) | 1.07 (0.09) |  |  $<$0.28 |  $<$0.33

Table 6: Line parameters of the CH3OH $J_{K}$=$7_{0}$–$6_{0}$ $A^{+}$ line.aaThe quoted errors denote one standard deviation. Source | $T_{\rm pk}$ | $V_{LSR}$ | $\Delta V$ |  $\int T_{a}^{*}dV$bbVelocity range for integration is $\pm 5$ km s-1 centered at the $LSR$ velocity of N2H+ $J$=1–0 or NH3 (1, 1).
---|---|---|---|---
| [K] | [km s-1] | [km s-1] | [K km s-1]
G015.05+00.07 MM1 |  $<$0.29 | — | — |  $<$0.6
G015.31-00.16 MM2 |  $<$0.30 | — | — |  $<$0.6
G015.31-00.16 MM3 |  $<$0.40 | — | — |  $<$0.8
G019.27+0.07 MM1 | 0.57 (0.04) | 26.7 (0.2) | 5.2 (0.4) | 3.1 (0.2)
G019.27+0.07 MM2 |  $<$0.28 | — | — |  $<$0.6
G022.35+00.41 MM1 | 0.64 (0.04) | 52.6 (0.2) | 5.4 (0.4) | 3.6 (0.2)
G022.35+00.41 MM2 |  $<$0.34 | — | — |  $<$0.7
G022.35+00.41 MM3 |  $<$0.28 | — | — |  $<$0.6
G023.60+00.00 MM1 | 0.67 (0.04) | 107.1 (0.2) | 4.9 (0.4) | 3.5 (0.2)
G023.60+00.00 MM2 | 0.34 (0.03) | 53.0 (0.3) | 6.7 (0.7) | 2.2 (0.2)
G023.60+00.00 MM3 |  $<$0.25 | — | — |  $<$0.5
G023.60+00.00 MM4 |  $<$0.25 | — | — |  $<$0.5
G023.60+00.00 MM7 |  $<$0.39 | — | — |  $<$0.8
G024.08+00.04 MM1 |  $<$0.34 | — | — |  $<$0.7
G024.08+00.04 MM2(1) |  $<$0.46 | — | — |  $<$1.0
G024.08+00.04 MM2(2) |  $<$0.46 | — | — |  $<$1.0
G024.08+00.04 MM3 |  $<$0.31 | — | — |  $<$0.7
G024.08+00.04 MM4 |  $<$0.39 | — | — |  $<$0.8
G024.33+00.11 MM1 | 0.48 (0.04) | 114.2 (0.3) | 6.6 (0.6) | 3.0 (0.2)
G024.33+00.11 MM2 |  $<$0.29 | — | — |  $<$0.6
G024.33+00.11 MM3 |  $<$0.19 | — | — |  $<$0.4
G024.33+00.11 MM4 |  $<$0.28 | — | — |  $<$0.6
G024.33+00.11 MM5 |  $<$0.28 | — | — |  $<$0.6
G024.33+00.11 MM6 |  $<$0.36 | — | — |  $<$0.8
G024.33+00.11 MM8 |  $<$0.24 | — | — |  $<$0.5
G024.33+00.11 MM9 |  $<$0.30 | — | — |  $<$0.6
G024.33+00.11 MM11 |  $<$0.26 | — | — |  $<$0.5
G024.60+00.08 MM1 | 0.32 (0.03) | 52.1 (0.3) | 5.9 (0.7) | 1.9 (0.2)
G024.60+00.08 MM2 |  $<$0.32 | — | — |  $<$0.7
G025.04-00.20 MM1 |  $<$0.28 | — | — |  $<$0.6
G025.04-00.20 MM2 |  $<$0.27 | — | — |  $<$0.6
G025.04-00.20 MM4 |  $<$0.33 | — | — |  $<$0.7
G034.43+00.24 MM1 | 1.79 (0.09) | 57.6 (0.1) | 4.8 (0.3) | 9.5 (0.1)
G034.43+00.24 MM2 | 1.26 (0.06) | 57.7 (0.1) | 5.7 (0.3) | 7.3 (0.2)
G034.43+00.24 MM3 | 0.73 (0.03) | 58.8 (0.2) | 8.6 (0.5) | 5.4 (0.1)
G034.43+00.24 MM4 | 0.57 (0.05) | 57.2 (0.2) | 4.1 (0.4) | 2.5 (0.2)
G034.43+00.24 MM5 |  $<$0.30 | — | — |  $<$0.6
G034.43+00.24 MM6 |  $<$0.31 | — | — |  $<$0.7
G034.43+00.24 MM8 |  $<$0.28 | — | — |  $<$0.6
G034.43+00.24 MM9 |  $<$0.32 | — | — |  $<$0.7
I18102-1800 MM1 | 0.67 (0.03) | 21.7 (0.2) | 6.2 (0.4) | 4.2 (0.1)
I18151-1208 MM1 | 0.30 (0.05) | 33.1 (0.3) | 3.6 (0.6) | 1.1 (0.2)
I18151-1208 MM2 | 0.51 (0.04) | 30.4 (0.3) | 7.1 (0.6) | 3.3 (0.2)
I18151-1208 MM3 |  $<$0.27 | — | — |  $<$0.6
I18182-1433 MM1 | 0.43 (0.04) | 60.0 (0.2) | 4.4 (0.5) | 2.0 (0.2)
I18182-1433 MM2 |  $<$0.39 | — | — |  $<$0.8
I18223-1243 MM1 |  $<$0.37 | — | — |  $<$0.8
I18223-1243 MM2 |  $<$0.42 | — | — |  $<$0.9
I18223-1243 MM3 | 0.27 (0.03) | 44.9 (0.3) | 5.4 (0.6) | 1.5 (0.1)
I18223-1243 MM4 |  $<$0.29 |  |  |  $<$0.6
I18306-0835 MM1 | 0.50 (0.04) | 78.0 (0.2) | 3.6 (0.4) | 1.6 (0.1)
I18306-0835 MM2 |  $<$0.45 | — | — |  $<$0.9
I18306-0835 MM3 |  $<$0.43 | — | — |  $<$0.9
I18337-0743 MM1 | 0.34 (0.03) | 58.1 (0.3) | 5.7 (0.6) | 1.9 (0.1)
I18337-0743 MM2 |  $<$0.25 | — | — |  $<$0.5
I18337-0743 MM3 | 0.23 (0.03) | 56.1 (0.3) | 5.0 (0.8) | 1.3 (0.1)

Table 7: Line parameters of the NH3 ($J$, $K$) = (1, 1) line.aaThe quoted errors denote one standard deviation. Source | $T_{\rm pk}$ | $V_{LSR}$ | $\Delta V$ |  $\int T_{a}^{*}dV$bbVelocity range for integration is $\pm 5$ km s-1 centered at the $LSR$ velocity of N2H+ $J$=1–0 or NH3 (1, 1).
---|---|---|---|---
| [K] | [km s-1] | [km s-1] | [K km s-1]
G015.05+00.07 MM1 | 0.41 (0.02) | 24.72 (0.04) | 2.3 (0.1) | 1.16 (0.04)
G015.31-00.16 MM2 | 0.45 (0.02) | 31.05 (0.03) | 1.34 (0.07) | 0.72 (0.04)
G015.31-00.16 MM3 | 0.38 (0.02) | 30.93 (0.03) | 1.27 (0.07) | 0.50 (0.04)
G019.27+0.07 MM1 | 0.93 (0.03) | 26.37 (0.03) | 2.57 (0.08) | 2.85 (0.04)
G019.27+0.07 MM2 | 0.86 (0.02) | 26.79 (0.04) | 2.71 (0.09) | 2.68 (0.04)
G022.35+00.41 MM1 | 0.36 (0.01) | 52.67 (0.05) | 3.0 (0.1) | 1.31 (0.03)
G022.35+00.41 MM2 | 0.29 (0.02) | 60.22 (0.04) | 1.5 (0.1) | 0.53 (0.04)
G022.35+00.41 MM3 | 0.78 (0.02) | 84.29 (0.03) | 2.45 (0.07) | 2.06 (0.04)
G023.60+00.00 MM1 | 0.60 (0.02) | 106.10 (0.05) | 4.1 (0.1) | 2.72 (0.03)
G023.60+00.00 MM2 | 1.02 (0.02) | 53.49 (0.03) | 2.47 (0.07) | 2.93 (0.04)
G023.60+00.00 MM3 | 0.76 (0.02) | 105.45 (0.05) | 3.6 (0.1) | 3.06 (0.04)
G023.60+00.00 MM4 | 0.78 (0.02) | 53.65 (0.03) | 2.2 (0.07) | 2.06 (0.04)
G023.60+00.00 MM7 | 1.04 (0.03) | 53.74 (0.03) | 2.22 (0.07) | 2.74 (0.04)
G024.08+00.04 MM1 | 0.55 (0.02) | 113.61 (0.04) | 2.9 (0.1) | 1.92 (0.04)
G024.08+00.04 MM2(1) | 0.31 (0.02) | 51.80 (0.06) | 1.6 (0.1) | 0.69 (0.04)
G024.08+00.04 MM2(2) | 0.39 (0.02) | 114.02 (0.05) | 2.4 (0.1) | 1.14 (0.04)
G024.08+00.04 MM3 | 0.52 (0.02) | 51.59 (0.03) | 1.89 (0.07) | 1.21 (0.04)
G024.08+00.04 MM4 | 0.55 (0.02) | 51.59 (0.03) | 1.67 (0.07) | 1.18 (0.04)
G024.33+00.11 MM1 | 1.25 (0.04) | 113.61 (0.05) | 3.4 (0.1) | 4.88 (0.06)
G024.33+00.11 MM2 | 0.71 (0.02) | 118.11 (0.05) | 3.5 (0.1) | 2.50 (0.05)
G024.33+00.11 MM3 p1 | 0.58 (0.01) | 116.63 (0.04) | 2.16 (0.09) | 2.26 (0.05)
G024.33+00.11 MM3 p2 | 0.47 (0.01) | 119.09 (0.05) | 1.9 (0.1) |
G024.33+00.11 MM4 | 0.55 (0.02) | 114.89 (0.07) | 4.6 (0.2) | 2.84 (0.05)
G024.33+00.11 MM5 | 0.97 (0.01) | 117.47 (0.03) | 3.06 (0.06) | 3.18 (0.05)
G024.33+00.11 MM6 | 1.02 (0.03) | 113.85 (0.05) | 3.2 (0.1) | 3.77 (0.06)
G024.33+00.11 MM8 | 0.29 (0.02) | 119.93 (0.09) | 2.8 (0.2) | 1.65 (0.03)
G024.33+00.11 MM9 p1 | 0.38 (0.01) | 116.18 (0.04) | 1.98 (0.09) | 1.99 (0.03)
G024.33+00.11 MM9 p2 | 0.45 (0.01) | 119.28 (0.03) | 1.90 (0.08) |
G024.33+00.11 MM11 | 0.59 (0.02) | 112.99 (0.04) | 2.4 (0.1) | 1.60 (0.06)
G024.60+00.08 MM1 | 0.93 (0.02) | 52.99 (0.03) | 2.37 (0.07) | 2.61 (0.04)
G024.60+00.08 MM2 | 0.34 (0.01) | 115.11 (0.04) | 2.3 (0.1) | 0.92 (0.04)
G025.04-00.20 MM1 | 1.18 (0.03) | 63.53 (0.02) | 2.08 (0.06) | 2.87 (0.04)
G025.04-00.20 MM2 | 0.86 (0.02) | 63.44 (0.03) | 2.56 (0.08) | 2.48 (0.04)
G025.04-00.20 MM4 | 1.00 (0.03) | 63.55 (0.03) | 2.03 (0.06) | 2.31 (0.04)
G034.43+00.24 MM1 | 1.77 (0.04) | 57.79 (0.04) | 3.39 (0.09) | 6.83 (0.03)
G034.43+00.24 MM2 | 1.58 (0.04) | 57.50 (0.04) | 3.8 (0.1) | 6.70 (0.03)
G034.43+00.24 MM3 | 1.16 (0.03) | 58.98 (0.03) | 2.56 (0.07) | 3.62 (0.04)
G034.43+00.24 MM4 | 1.43 (0.03) | 57.50 (0.04) | 3.28 (0.09) | 5.32 (0.04)
G034.43+00.24 MM5 | 0.73 (0.03) | 57.57 (0.04) | 2.3 (0.1) | 1.97 (0.06)
G034.43+00.24 MM6 | 0.85 (0.03) | 58.31 (0.04) | 2.59 (0.09) | 2.55 (0.06)
G034.43+00.24 MM8 | 1.29 (0.03) | 57.84 (0.04) | 3.14 (0.09) | 4.62 (0.06)
G034.43+00.24 MM9 | 1.10 (0.03) | 58.53 (0.04) | 2.62 (0.09) | 3.28 (0.06)
I18102-1800 MM1 | 1.63 (0.04) | 21.53 (0.04) | 2.88 (0.08) | 5.61 (0.04)
I18151-1208 MM1 | 0.58 (0.02) | 32.84 (0.03) | 2.37 (0.08) | 1.59 (0.04)
I18151-1208 MM2 | 0.45 (0.01) | 29.93 (0.04) | 2.9 (0.1) | 1.48 (0.04)
I18151-1208 MM3 | 0.23 (0.01) | 30.86 (0.06) | 2.1 (0.1) | 0.42 (0.04)
I18182-1433 MM1 | 0.75 (0.02) | 59.72 (0.04) | 3.18 (0.09) | 2.59 (0.04)
I18182-1433 MM2 | 0.53 (0.02) | 40.93 (0.04) | 2.08 (0.09) | 1.22 (0.05)
I18223-1243 MM1 | 0.93 (0.03) | 45.28 (0.03) | 1.87 (0.07) | 3.03 (0.03)
I18223-1243 MM2 | 0.82 (0.03) | 45.84 (0.05) | 2.9 (0.1) | 2.16 (0.06)
I18223-1243 MM3 | 0.92 (0.02) | 45.66 (0.04) | 2.95 (0.09) | 2.62 (0.06)
I18223-1243 MM4 | 0.62 (0.02) | 45.78 (0.03) | 1.73 (0.08) | 1.34 (0.06)
I18306-0835 MM1 | 0.91 (0.02) | 77.88 (0.03) | 2.57 (0.08) | 2.75 (0.04)
I18306-0835 MM2 | 0.29 (0.02) | 76.58 (0.07) | 2.3 (0.2) | 0.82 (0.06)
I18306-0835 MM3 | 0.37 (0.02) | 54.45 (0.06) | 2.1 (0.1) | 0.73 (0.06)
I18337-0743 MM1 | 1.38 (0.04) | 58.37 (0.05) | 3.7 (0.1) | 5.68 (0.04)
I18337-0743 MM2 | 0.32 (0.01) | 58.53 (0.07) | 3.2 (0.2) | 1.15 (0.04)
I18337-0743 MM3 | 0.45 (0.02) | 55.85 (0.05) | 3.2 (0.1) | 1.67 (0.05)

Table 8: Line parameters of the NH3 ($J$, $K$) = (2, 2) line.aaThe quoted errors denote one standard deviation. Source | $T_{\rm pk}$ | $V_{LSR}$ | $\Delta V$ |  $\int T_{a}^{*}dV$bbVelocity range for integration is $\pm 5$ km s-1 centered at the $LSR$ velocity of N2H+ $J$=1–0 or NH3 (1, 1).
---|---|---|---|---
| [K] | [km s-1] | [km s-1] | [K km s-1]
G015.05+00.07 MM1 | 0.18 (0.01) | 24.60 (0.08) | 2.1 (0.2) | 0.48 (0.05)
G015.31-00.16 MM2 |  $<$0.09 | — | — |  $<$0.14
G015.31-00.16 MM3 |  $<$0.08 | — | — |  $<$0.13
G019.27+0.07 MM1 | 0.43 (0.01) | 26.37 (0.03) | 2.24 (0.07) | 1.08 (0.04)
G019.27+0.07 MM2 | 0.40 (0.01) | 26.92 (0.04) | 2.44 (0.09) | 1.19 (0.04)
G022.35+00.41 MM1 | 0.17 (0.01) | 52.57 (0.07) | 2.0 (0.2) | 0.43 (0.04)
G022.35+00.41 MM2 |  $<$0.08 | — | — | 0.27 (0.05)
G022.35+00.41 MM3 | 0.30 (0.01) | 84.32 (0.03) | 2.1 (0.1) | 0.81 (0.05)
G023.60+00.00 MM1 | 0.31 (0.01) | 106.37 (0.04) | 3.3 (0.1) | 1.11 (0.03)
G023.60+00.00 MM2 | 0.46 (0.01) | 53.47 (0.03) | 2.62 (0.07) | 1.47 (0.04)
G023.60+00.00 MM3 | 0.32 (0.01) | 105.73 (0.06) | 3.8 (0.1) | 1.29 (0.04)
G023.60+00.00 MM4 | 0.30 (0.01) | 53.44 (0.04) | 2.2 (0.1) | 0.71 (0.04)
G023.60+00.00 MM7 | 0.33 (0.01) | 53.6 (0.04) | 2.0 (0.1) | 0.73 (0.05)
G024.08+00.04 MM1 | 0.30 (0.01) | 113.66 (0.05) | 2.5 (0.1) | 0.87 (0.04)
G024.08+00.04 MM2(1) | 0.12 (0.02) | 51.75 (0.08) | 1.1 (0.2) | 0.12 (0.04)
G024.08+00.04 MM2(2) | 0.17 (0.01) | 114.17 (0.07) | 2.1 (0.2) | 0.38 (0.04)
G024.08+00.04 MM3 | 0.12 (0.01) | 51.62 (0.09) | 1.7 (0.2) | 0.16 (0.04)
G024.08+00.04 MM4 | 0.15 (0.01) | 51.63 (0.07) | 1.5 (0.2) | 0.23 (0.04)
G024.33+00.11 MM1 | 0.84 (0.02) | 113.46 (0.03) | 3.04 (0.07) | 2.84 (0.06)
G024.33+00.11 MM2 | 0.34 (0.01) | 118.00 (0.06) | 3.1 (0.2) | 1.05 (0.06)
G024.33+00.11 MM3 p1 | 0.18 (0.01) | 116.9 (0.1) | 2.4 (0.3) | 0.62 (0.06)
G024.33+00.11 MM3 p2 | 0.17 (0.02) | 119.24 (0.08) | 1.2 (0.2) |
G024.33+00.11 MM4 | 0.16 (0.01) | 114.61 (0.2) | 4.8 (0.4) | 0.80 (0.05)
G024.33+00.11 MM5 | 0.47 (0.01) | 117.4 (0.05) | 2.9 (0.1) | 1.28 (0.05)
G024.33+00.11 MM6 | 0.62 (0.02) | 113.76 (0.04) | 3.02 (0.09) | 2.08 (0.06)
G024.33+00.11 MM8 | 0.10 (0.01) | 119.4 (0.1) | 2.0 (0.3) | 0.41 (0.03)
G024.33+00.11 MM9 p1 | 0.13 (0.01) | 116.26 (0.07) | 2.2 (0.2) | 0.62 (0.03)
G024.33+00.11 MM9 p2 | 0.19 (0.01) | 119.22 (0.04) | 1.4 (0.1) |
G024.33+00.11 MM11 | 0.24 (0.02) | 112.91 (0.09) | 2.5 (0.2) | 0.67 (0.06)
G024.60+00.08 MM1 | 0.37 (0.01) | 52.98 (0.04) | 2.4 (0.1) | 1.10 (0.04)
G024.60+00.08 MM2 | 0.14 (0.01) | 114.7 (0.1) | 3.4 (0.3) | 0.55 (0.04)
G025.04-00.20 MM1 | 0.44 (0.01) | 63.6 (0.03) | 2.18 (0.08) | 1.12 (0.04)
G025.04-00.20 MM2 | 0.25 (0.01) | 63.52 (0.07) | 2.9 (0.2) | 0.88 (0.05)
G025.04-00.20 MM4 | 0.28 (0.01) | 63.61 (0.05) | 2.1 (0.1) | 0.64 (0.05)
G034.43+00.24 MM1 | 1.02 (0.01) | 57.71 (0.02) | 3.54 (0.04) | 4.06 (0.04)
G034.43+00.24 MM2 | 0.93 (0.01) | 57.53 (0.02) | 3.66 (0.05) | 3.73 (0.04)
G034.43+00.24 MM3 | 0.46 (0.01) | 58.97 (0.03) | 2.91 (0.08) | 1.60 (0.04)
G034.43+00.24 MM4 | 0.76 (0.01) | 57.49 (0.02) | 3.17 (0.05) | 2.64 (0.04)
G034.43+00.24 MM5 | 0.28 (0.02) | 57.59 (0.07) | 1.9 (0.2) | 0.57 (0.06)
G034.43+00.24 MM6 | 0.27 (0.02) | 58.62 (0.08) | 2.5 (0.2) | 0.85 (0.07)
G034.43+00.24 MM8 | 0.63 (0.02) | 57.94 (0.04) | 3.3 (0.1) | 2.37 (0.07)
G034.43+00.24 MM9 | 0.36 (0.02) | 58.99 (0.06) | 2.3 (0.1) | 0.82 (0.07)
I18102-1800 MM1 | 0.93 (0.01) | 21.57 (0.02) | 3.04 (0.05) | 3.28 (0.05)
I18151-1208 MM1 | 0.34 (0.01) | 32.92 (0.04) | 2.2 (0.1) | 0.90 (0.05)
I18151-1208 MM2 | 0.20 (0.01) | 30.0 (0.1) | 4.2 (0.2) | 0.97 (0.05)
I18151-1208 MM3 | 0.11 (0.01) | 31.2 (0.2) | 3.6 (0.4) | 0.45 (0.04)
I18182-1433 MM1 | 0.39 (0.01) | 59.69 (0.04) | 3.0 (0.1) | 1.15 (0.04)
I18182-1433 MM2 | 0.17 (0.01) | 40.9 (0.1) | 2.6 (0.2) | 0.42 (0.05)
I18223-1243 MM1 | 0.48 (0.02) | 45.20 (0.04) | 2.2 (0.1) | 1.21 (0.04)
I18223-1243 MM2 | 0.33 (0.02) | 45.72 (0.07) | 2.8 (0.2) | 1.28 (0.06)
I18223-1243 MM3 | 0.42 (0.01) | 45.69 (0.03) | 2.57 (0.07) | 0.93 (0.06)
I18223-1243 MM4 | 0.23 (0.02) | 45.75 (0.08) | 1.8 (0.2) | 0.56 (0.06)
I18306-0835 MM1 | 0.49 (0.01) | 77.87 (0.04) | 2.82 (0.08) | 1.56 (0.04)
I18306-0835 MM2 | 0.12 (0.02) | 76.7 (0.2) | 2.5 (0.4) | 0.23 (0.06)
I18306-0835 MM3 | 0.13 (0.02) | 55.2 (0.2) | 2.3 (0.4) | 0.30 (0.06)
I18337-0743 MM1 | 0.77 (0.01) | 58.37 (0.03) | 3.52 (0.06) | 2.92 (0.05)
I18337-0743 MM2 | 0.18 (0.01) | 59.99 (0.09) | 2.4 (0.2) | 0.37 (0.05)
I18337-0743 MM3 | 0.16 (0.01) | 56.3 (0.1) | 2.9 (0.3) | 0.59 (0.05)

Table 9: Line parameters of the NH3 ($J$, $K$) = (3, 3) line.aaThe quoted errors denote one standard deviation. Source | $T_{\rm pk}$ | $V_{LSR}$ | $\Delta V$ |  $\int T_{a}^{*}dV$bbVelocity range for integration is $\pm 5$ km s-1 centered at the $LSR$ velocity of N2H+ $J$=1–0 or NH3 (1, 1).
---|---|---|---|---
| [K] | [km s-1] | [km s-1] | [K km s-1]
G015.05+00.07 MM1 |  $<$0.08 | — | — | 0.34 (0.04)
G015.31-00.16 MM2 |  $<$0.08 | — | — |  $<$0.13
G015.31-00.16 MM3 |  $<$0.08 | — | — |  $<$0.12
G019.27+0.07 MM1 | 0.16 (0.01) | 26.6 (0.1) | 4.0 (0.3) | 0.69 (0.04)
G019.27+0.07 MM2 | 0.16 (0.01) | 27.0 (0.1) | 3.9 (0.3) | 0.77 (0.04)
G022.35+00.41 MM1 | 0.15 (0.01) | 52.97 (0.07) | 4.5 (0.2) | 0.86 (0.04)
G022.35+00.41 MM2 |  $<$0.08 | — | — |  $<$0.12
G022.35+00.41 MM3 |  $<$0.08 | — | — | 0.24 (0.04)
G023.60+00.00 MM1 | 0.19 (0.01) | 106.56 (0.09) | 5.0 (0.2) | 0.99 (0.03)
G023.60+00.00 MM2 | 0.23 (0.01) | 53.51 (0.08) | 5.2 (0.2) | 1.29 (0.03)
G023.60+00.00 MM3 | 0.17 (0.01) | 106.3 (0.1) | 4.3 (0.3) | 0.82 (0.04)
G023.60+00.00 MM4 | 0.19 (0.01) | 53.46 (0.09) | 2.9 (0.2) | 0.72 (0.05)
G023.60+00.00 MM7 | 0.14 (0.01) | 53.3 (0.1) | 4.2 (0.3) | 0.72 (0.04)
G024.08+00.04 MM1 | 0.11 (0.01) | 113.9 (0.1) | 2.7 (0.3) | 0.28 (0.03)
G024.08+00.04 MM2(1) |  $<$0.07 | — | — |  $<$0.11
G024.08+00.04 MM2(2) |  $<$0.07 | — | — |  $<$0.11
G024.08+00.04 MM3 |  $<$0.07 | — | — | 0.13 (0.04)
G024.08+00.04 MM4 |  $<$0.07 | — | — |  $<$0.11
G024.33+00.11 MM1 | 0.70 (0.01) | 113.81 (0.04) | 4.2 (0.1) | 3.30 (0.06)
G024.33+00.11 MM2 | 0.18 (0.01) | 117.6 (0.2) | 5.6 (0.4) | 1.01 (0.05)
G024.33+00.11 MM3 | 0.12 (0.01) | 118.2 (0.2) | 5.7 (0.5) | 0.76 (0.05)
G024.33+00.11 MM4 | 0.14 (0.02) | 114.9 (0.1) | 2.1 (0.3) | 0.31 (0.05)
G024.33+00.11 MM5 | 0.19 (0.01) | 119.1 (0.1) | 5.0 (0.3) | 1.02 (0.05)
G024.33+00.11 MM6 | 0.48 (0.01) | 113.98 (0.05) | 3.7 (0.1) | 2.07 (0.06)
G024.33+00.11 MM8 |  $<$0.07 | — | — | 0.19 (0.03)
G024.33+00.11 MM9 |  $<$0.07 | — | — | 0.26 (0.03)
G024.33+00.11 MM11 |  $<$0.12 | — | — | 0.36 (0.06)
G024.60+00.08 MM1 | 0.11 (0.01) | 52.2 (0.2) | 7.6 (0.5) | 0.78 (0.04)
G024.60+00.08 MM2 |  $<$0.08 | — | — | 0.41 (0.04)
G025.04-00.20 MM1 | 0.13 (0.01) | 63.2 (0.1) | 3.0 (0.3) | 0.44 (0.04)
G025.04-00.20 MM2 | 0.10 (0.01) | 63.7 (0.2) | 3.4 (0.4) | 0.41 (0.04)
G025.04-00.20 MM4 |  $<$0.08 | — | — | 0.18 (0.04)
G034.43+00.24 MM1 | 0.66 (0.01) | 57.9 (0.03) | 5.17 (0.08) | 3.58 (0.04)
G034.43+00.24 MM2 | 0.59 (0.01) | 57.65 (0.04) | 5.76 (0.09) | 3.45 (0.04)
G034.43+00.24 MM3 | 0.215 (0.006) | 59.4 (0.1) | 7.2 (0.2) | 1.42 (0.04)
G034.43+00.24 MM4 | 0.399 (0.007) | 57.55 (0.05) | 5.2 (0.1) | 2.15 (0.04)
G034.43+00.24 MM5 |  $<$0.12 | — | — | 0.39 (0.06)
G034.43+00.24 MM6 |  $<$0.12 | — | — | 0.33 (0.06)
G034.43+00.24 MM8 | 0.33 (0.02) | 57.8 (0.1) | 4.3 (0.2) | 1.53 (0.07)
G034.43+00.24 MM9 | 0.19 (0.02) | 59.2 (0.1) | 2.9 (0.3) | 0.64 (0.07)
I18102-1800 MM1 | 0.61 (0.01) | 21.47 (0.03) | 4.71 (0.08) | 3.01 (0.04)
I18151-1208 MM1 | 0.14 (0.01) | 32.8 (0.1) | 3.4 (0.3) | 0.58 (0.04)
I18151-1208 MM2 | 0.11 (0.01) | 29.4 (0.2) | 6.8 (0.5) | 0.72 (0.05)
I18151-1208 MM3 |  $<$0.08 | — | — | 0.29 (0.04)
I18182-1433 MM1 | 0.17 (0.01) | 59.4 (0.1) | 6 (0.3) | 1.02 (0.04)
I18182-1433 MM2 |  $<$0.09 | — | — | 0.19 (0.05)
I18223-1243 MM1 | 0.16 (0.02) | 45.2 (0.1) | 1.9 (0.3) | 0.36 (0.06)
I18223-1243 MM2 |  $<$0.12 | — | — | 0.32 (0.06)
I18223-1243 MM3 | 0.15 (0.01) | 45.1 (0.1) | 5.3 (0.3) | 0.8 (0.03)
I18223-1243 MM4 |  $<$0.12 | — | — | 0.24 (0.07)
I18306-0835 MM1 | 0.31 (0.01) | 78.04 (0.06) | 3.5 (0.1) | 1.22 (0.04)
I18306-0835 MM2 | 0.09 (0.02) | 77.6 (0.2) | 2.8 (0.5) | 0.3 (0.06)
I18306-0835 MM3 |  $<$0.11 | — | — |  $<$0.18
I18337-0743 MM1 | 0.39 (0.01) | 58.29 (0.06) | 4.8 (0.1) | 1.99 (0.05)
I18337-0743 MM2 | 0.13 (0.01) | 58.3 (0.1) | 2.5 (0.3) | 0.32 (0.04)
I18337-0743 MM3 |  $<$0.08 | — | — | 0.67 (0.04)

Table 10: The NH3 rotation temperatures and column densities. Source |  $T_{\rm rot}$(NH3) |  $N$(N2H+)aaTex(N2H+) is assumed to be equal to $T_{\rm ex}$(NH3). The quoted error is dominated by the error in $T_{\rm ex}$(NH3). |  $N$(CCS)aaTex(N2H+) is assumed to be equal to $T_{\rm ex}$(NH3). The quoted error is dominated by the error in $T_{\rm ex}$(NH3). |  $N$(HC3N)aaTex(N2H+) is assumed to be equal to $T_{\rm ex}$(NH3). The quoted error is dominated by the error in $T_{\rm ex}$(NH3). |  $N$(NH3) |  $N$(CH3OH)bbTex(CH3OH) is assumed to be from 20 K to 50 K. |  $N$(CCS)/$N$(N2H+) |  $N$(CCS)/$N$(NH3)
---|---|---|---|---|---|---|---|---
| [K] | [1012 cm-2] | [1012 cm-2] | [1012 cm-2] | [1015 cm-2] | [1014 cm-5] |  | [10-2]
G015.05+00.07 MM1 | 15.2${}_{-1.5}^{+1.7}$ | 17.4${}_{-1.0}^{+1.2}$ |  $<$3.8 | 9.7${}_{-0.4}^{+0.5}$ | 2.7${}_{-0.8}^{+0.6}$ |  $<$2.2 |  $<$0.24 |  $<$0.20
G015.31-00.16 MM2 | 10.3${}_{-0.6}^{+0.7}$ | 5.4${}_{-0.1}^{+0.1}$ |  $<$1.6 | 5.0${}_{-0.1}^{+0.1}$ | 1.1${}_{-0.6}^{+0.5}$ |  $<$2.3 |  $<$0.30 |  $<$0.32
G015.31-00.16 MM3 | 12.6${}_{-2.0}^{+2.4}$ | 6.9${}_{-0.5}^{+0.7}$ |  $<$1.7 | 4.4${}_{-0.2}^{+0.3}$ | 0.6${}_{-0.5}^{+0.4}$ |  $<$3.1 |  $<$0.27 |  $<$1.74
G019.27+0.07 MM1 | 15.4${}_{-1.0}^{+1.1}$ | 52.0${}_{-2.1}^{+2.4}$ |  $<$3.7 | 24.2${}_{-0.7}^{+0.8}$ | 3.1${}_{-0.6}^{+0.6}$ | 7.9—16 |  $<$0.07 |  $<$0.15
G019.27+0.07 MM2 | 15.8${}_{-0.9}^{+1.0}$ | 29.2${}_{-1.1}^{+1.2}$ |  $<$3.5 | 22.1${}_{-0.6}^{+0.7}$ | 3.0${}_{-0.6}^{+0.5}$ |  $<$2.2 |  $<$0.12 |  $<$0.15
G022.35+00.41 MM1 | 16.0${}_{-1.4}^{+1.6}$ | 26.7${}_{-1.4}^{+1.7}$ |  $<$3.6 | 18.3${}_{-0.7}^{+0.8}$ | 3.3${}_{-0.8}^{+0.7}$ | 9.2—18.7 |  $<$0.14 |  $<$0.15
G022.35+00.41 MM2 | 12.8${}_{-1.7}^{+2.2}$ | 4.9${}_{-0.3}^{+0.4}$ |  $<$1.7 |  $<$2.2 | 1.3${}_{-0.9}^{+0.6}$ |  $<$2.6 |  $<$0.37 |  $<$0.42
G022.35+00.41 MM3 | 15.2${}_{-1.0}^{+1.1}$ | 15.8${}_{-0.6}^{+0.7}$ |  $<$3.0 | 5.5${}_{-0.1}^{+0.2}$ | 2.2${}_{-0.5}^{+0.5}$ |  $<$2.1 |  $<$0.20 |  $<$0.18
G023.60+00.00 MM1 | 17.0${}_{-1.2}^{+1.3}$ | 36.7${}_{-1.7}^{+1.9}$ |  $<$5.2 | 22.2${}_{-0.7}^{+0.8}$ | 4.3${}_{-0.7}^{+0.7}$ | 8.9—18 |  $<$0.15 |  $<$0.14
G023.60+00.00 MM2 | 16.0${}_{-0.9}^{+1.0}$ | 22.8${}_{-0.8}^{+0.9}$ |  $<$3.8 | 31.6${}_{-0.8}^{+0.9}$ | 2.5${}_{-0.5}^{+0.5}$ | 5.5—11.2 |  $<$0.17 |  $<$0.19
G023.60+00.00 MM3 | 16.4${}_{-1.1}^{+1.2}$ | 17.5${}_{-0.7}^{+0.8}$ |  $<$4.8 | 3.9${}_{-0.1}^{+0.1}$ | 2.6${}_{-0.7}^{+0.6}$ |  $<$1.9 |  $<$0.28 |  $<$0.25
G023.60+00.00 MM4 | 14.9${}_{-0.9}^{+1.1}$ | 8.6${}_{-0.3}^{+0.4}$ |  $<$3.5 | 7.0${}_{-0.2}^{+0.2}$ | 2.1${}_{-0.5}^{+0.5}$ |  $<$2.0 |  $<$0.42 |  $<$0.22
G023.60+00.00 MM7 | 13.1${}_{-0.7}^{+0.8}$ | 16.0${}_{-0.5}^{+0.5}$ |  $<$2.6 | 13.6${}_{-0.2}^{+0.3}$ | 2.7${}_{-0.6}^{+0.5}$ |  $<$3.0 |  $<$0.17 |  $<$0.13
G024.08+00.04 MM1 | 16.4${}_{-1.4}^{+1.6}$ | 38.9${}_{-2.1}^{+2.4}$ |  $<$3.8 | 8.5${}_{-0.3}^{+0.4}$ | 4.0${}_{-0.9}^{+0.7}$ |  $<$3.6 |  $<$0.10 |  $<$0.12
G024.08+00.04 MM2(1) | 14.9${}_{-2.6}^{+3.4}$ | 8.1${}_{-0.8}^{+1.1}$ |  $<$2.6 | 4.0${}_{-0.3}^{+0.4}$ | 1.3${}_{-0.9}^{+0.7}$ |  $<$3.6 |  $<$0.36 |  $<$0.65
G024.08+00.04 MM2(2) | 15.1${}_{-1.6}^{+1.9}$ | 10.5${}_{-0.7}^{+0.8}$ |  $<$3.1 | 3.5${}_{-0.1}^{+0.2}$ | 2.8${}_{-0.9}^{+0.7}$ |  $<$3.6 |  $<$0.32 |  $<$0.16
G024.08+00.04 MM3 | 12.1${}_{-0.9}^{+1.0}$ | 5.1${}_{-0.2}^{+0.2}$ |  $<$3.1 | 6.7${}_{-0.1}^{+0.2}$ | 2.0${}_{-0.6}^{+0.5}$ |  $<$2.4 |  $<$0.63 |  $<$0.22
G024.08+00.04 MM4 | 12.9${}_{-0.9}^{+1.1}$ | 4.6${}_{-0.2}^{+0.2}$ |  $<$1.7 | 7.2${}_{-0.1}^{+0.2}$ | 1.7${}_{-0.5}^{+0.4}$ |  $<$3.0 |  $<$0.39 |  $<$0.14
G024.33+00.11 MM1 | 18.8${}_{-1.6}^{+1.8}$ | 63.3${}_{-3.6}^{+4.1}$ |  $<$6.6 | 33.0${}_{-1.4}^{+1.7}$ | 5.0${}_{-0.8}^{+0.7}$ | 7.7—15.6 |  $<$0.11 |  $<$0.16
G024.33+00.11 MM2 | 16.6${}_{-1.2}^{+1.3}$ | 20.8${}_{-0.9}^{+1.1}$ |  $<$5.1 | 12.2${}_{-0.4}^{+0.5}$ | 3.4${}_{-0.8}^{+0.7}$ |  $<$2.6 |  $<$0.26 |  $<$0.20
G024.33+00.11 MM3 p1 | 13.9${}_{-0.7}^{+0.7}$ | 21.9${}_{-0.6}^{+0.6}$ |  $<$5.5 | 11.7${}_{-0.2}^{+0.2}$ | 2.1${}_{-0.4}^{+0.3}$ |  $<$1.5 |  $<$0.26 |  $<$0.32
G024.33+00.11 MM3 p2 | 14.5${}_{-1.3}^{+1.4}$ |  |  |  | 1.8${}_{-0.4}^{+0.3}$ |  |  |
G024.33+00.11 MM4 | 13.4${}_{-0.9}^{+1.0}$ | 11.5${}_{-0.4}^{+0.5}$ |  $<$4.6 | 9.8${}_{-0.2}^{+0.3}$ | 4.2${}_{-1.1}^{+0.9}$ |  $<$2.1 |  $<$0.42 |  $<$0.15
G024.33+00.11 MM5 | 17.1${}_{-0.5}^{+0.5}$ | 23.7${}_{-0.5}^{+0.5}$ |  $<$4.7 | 14.4${}_{-0.2}^{+0.2}$ | 2.7${}_{-0.2}^{+0.2}$ |  $<$2.2 |  $<$0.20 |  $<$0.19
G024.33+00.11 MM6 | 17.3${}_{-1.4}^{+1.6}$ | 14.3${}_{-0.8}^{+0.9}$ |  $<$5.7 | 7.2${}_{-0.3}^{+0.3}$ | 4.7${}_{-0.8}^{+0.7}$ |  $<$2.8 |  $<$0.42 |  $<$0.15
G024.33+00.11 MM8 | — | — | — | — | — |  $<$1.9 | — | —
G024.33+00.11 MM9 p1 | 15.1${}_{-1.1}^{+1.2}$ |  |  |  |  |  |  |
G024.33+00.11 MM9 p2 | 15.2${}_{-0.9}^{+1.0}$ | 7.7${}_{-0.3}^{+0.3}$ |  $<$3.9 | 4.6${}_{-0.1}^{+0.1}$ | 2.2${}_{-0.4}^{+0.3}$ |  $<$2.3 |  $<$0.52 |  $<$0.21
G024.33+00.11 MM11 | 14.8${}_{-1.4}^{+1.7}$ | 8.6${}_{-0.5}^{+0.6}$ |  $<$4.2 |  $<$2.5 | 2.7${}_{-0.8}^{+0.6}$ |  $<$2.0 |  $<$0.51 |  $<$0.22
G024.60+00.08 MM1 | 15.3${}_{-0.8}^{+0.9}$ | 28.5${}_{-0.9}^{+1.0}$ |  $<$3.2 | 24.0${}_{-0.5}^{+0.6}$ | 2.1${}_{-0.5}^{+0.4}$ | 4.9—9.9 |  $<$0.12 |  $<$0.20
G024.60+00.08 MM2 | 14.2${}_{-1.1}^{+1.2}$ | 25.9${}_{-1.1}^{+1.3}$ |  $<$4.2 | 11.1${}_{-0.3}^{+0.4}$ | 3.1${}_{-0.6}^{+0.5}$ |  $<$3.0 |  $<$0.17 |  $<$0.17
G025.04-00.20 MM1 | 14.7${}_{-0.8}^{+0.9}$ | 27.9${}_{-0.9}^{+1.0}$ |  $<$3.6 | 15.2${}_{-0.3}^{+0.4}$ | 2.0${}_{-0.4}^{+0.4}$ |  $<$2.5 |  $<$0.13 |  $<$0.22
G025.04-00.20 MM2 | 13.1${}_{-0.7}^{+0.8}$ | 21.5${}_{-0.6}^{+0.7}$ |  $<$4.5 | 10.5${}_{-0.2}^{+0.2}$ | 2.7${}_{-0.6}^{+0.5}$ |  $<$2.1 |  $<$0.21 |  $<$0.21
G025.04-00.20 MM4 | 13.5${}_{-0.8}^{+0.9}$ | 16.2${}_{-0.5}^{+0.6}$ |  $<$3.3 | 5.9${}_{-0.1}^{+0.1}$ | 1.7${}_{-0.5}^{+0.4}$ |  $<$2.5 |  $<$0.21 |  $<$0.27
G034.43+00.24 MM1 | 18.5${}_{-1.0}^{+1.1}$ | 133.6${}_{-5.0}^{+5.4}$ |  $<$3.9 | 54.3${}_{-1.6}^{+1.7}$ | 3.4${}_{-0.6}^{+0.6}$ | 24.2—49.2 |  $<$0.03 |  $<$0.14
G034.43+00.24 MM2 | 18.8${}_{-1.0}^{+1.1}$ | 113.9${}_{-4.2}^{+4.5}$ |  $<$4.5 | 52.0${}_{-1.5}^{+1.6}$ | 3.8${}_{-0.6}^{+0.6}$ | 18.7—37.9 |  $<$0.04 |  $<$0.14
G034.43+00.24 MM3 | 15.5${}_{-0.9}^{+0.9}$ | 59.6${}_{-2.0}^{+2.2}$ |  $<$3.2 | 30.6${}_{-0.7}^{+0.8}$ | 2.2${}_{-0.5}^{+0.4}$ | 13.9—28.1 |  $<$0.06 |  $<$0.19
G034.43+00.24 MM4 | 17.6${}_{-1.0}^{+1.1}$ | 66.0${}_{-2.4}^{+2.7}$ |  $<$3.4 | 29.9${}_{-0.8}^{+0.9}$ | 3.3${}_{-0.6}^{+0.6}$ | 6.4—13 |  $<$0.05 |  $<$0.13
G034.43+00.24 MM5 | 14.3${}_{-1.3}^{+1.5}$ | 16.8${}_{-0.9}^{+1.0}$ |  $<$3.5 | 6.1${}_{-0.2}^{+0.3}$ | 2.7${}_{-0.8}^{+0.6}$ |  $<$2.3 |  $<$0.22 |  $<$0.18
G034.43+00.24 MM6 | 14.0${}_{-1.1}^{+1.3}$ | 15.4${}_{-0.7}^{+0.8}$ |  $<$3.2 | 11.2${}_{-0.3}^{+0.4}$ | 2.3${}_{-0.7}^{+0.5}$ |  $<$2.4 |  $<$0.22 |  $<$0.20
G034.43+00.24 MM8 | 17.2${}_{-1.1}^{+1.2}$ | 14.0${}_{-0.6}^{+0.6}$ |  $<$4.4 | 10.7${}_{-0.3}^{+0.4}$ | 2.8${}_{-0.6}^{+0.5}$ |  $<$2.1 |  $<$0.33 |  $<$0.20
G034.43+00.24 MM9 | 13.9${}_{-0.9}^{+1.1}$ | 20.1${}_{-0.8}^{+0.9}$ |  $<$3.2 | 11.7${}_{-0.3}^{+0.3}$ | 2.5${}_{-0.6}^{+0.5}$ |  $<$2.4 |  $<$0.16 |  $<$0.17
I18102-1800 MM1 | 17.9${}_{-1.1}^{+1.2}$ | 51.2${}_{-2.1}^{+2.3}$ |  $<$6.6 | 41.2${}_{-1.2}^{+1.4}$ | 3.2${}_{-0.6}^{+0.5}$ | 10.7—21.7 |  $<$0.13 |  $<$0.25
I18151-1208 MM1 | 20.8${}_{-1.7}^{+1.8}$ | 34.9${}_{-2.1}^{+2.2}$ |  $<$5.3 | 15.0${}_{-0.7}^{+0.8}$ | 1.3${}_{-0.5}^{+0.5}$ | 2.9—5.9 |  $<$0.16 |  $<$0.66
I18151-1208 MM2 | 17.8${}_{-1.4}^{+1.5}$ | 45.7${}_{-2.4}^{+2.6}$ |  $<$5.8 | 9.3${}_{-0.4}^{+0.4}$ | 1.5${}_{-0.6}^{+0.6}$ | 8.4—17 |  $<$0.13 |  $<$0.65
I18151-1208 MM3 | 16.0${}_{-2.1}^{+2.7}$ | 13.2${}_{-1.1}^{+1.4}$ |  $<$2.8 | 3.6${}_{-0.2}^{+0.3}$ | 2.4${}_{-1.0}^{+0.8}$ |  $<$2.1 |  $<$0.23 |  $<$0.20
I18182-1433 MM1 | 19.0${}_{-1.4}^{+1.5}$ | 55.8${}_{-2.7}^{+3.0}$ |  $<$5.8 | 31.6${}_{-1.2}^{+1.3}$ | 1.9${}_{-0.6}^{+0.6}$ | 5.1—10.3 |  $<$0.11 |  $<$0.45
I18182-1433 MM2 | 13.8${}_{-1.1}^{+1.2}$ | 17.0${}_{-0.7}^{+0.8}$ |  $<$3.8 | 3.4${}_{-0.1}^{+0.1}$ | 2.0${}_{-0.6}^{+0.5}$ |  $<$3.0 |  $<$0.23 |  $<$0.27
I18223-1243 MM1 | 17.5${}_{-1.5}^{+1.6}$ | 42.4${}_{-2.3}^{+2.6}$ |  $<$3.8 | 10.7${}_{-0.4}^{+0.5}$ | 1.8${}_{-0.4}^{+0.4}$ |  $<$3.3 |  $<$0.09 |  $<$0.27
I18223-1243 MM2 | 15.1${}_{-1.3}^{+1.4}$ | 25.2${}_{-1.2}^{+1.5}$ |  $<$3.8 | 6.3${}_{-0.2}^{+0.3}$ | 2.9${}_{-0.7}^{+0.6}$ |  $<$3.3 |  $<$0.16 |  $<$0.17
I18223-1243 MM3 | 16.2${}_{-0.9}^{+1.0}$ | 43.9${}_{-1.6}^{+1.7}$ |  $<$4.3 | 15.1${}_{-0.4}^{+0.4}$ | 2.9${}_{-0.6}^{+0.5}$ | 3.8—7.7 |  $<$0.10 |  $<$0.19
I18223-1243 MM4 | 15.5${}_{-1.5}^{+1.7}$ | 14.6${}_{-0.9}^{+1.0}$ |  $<$3.3 | 6.6${}_{-0.3}^{+0.3}$ | 1.2${}_{-0.5}^{+0.4}$ |  $<$2.2 |  $<$0.24 |  $<$0.47
I18306-0835 MM1 | 17.3${}_{-1.1}^{+1.2}$ | 22.6${}_{-0.9}^{+1.0}$ |  $<$5.9 | 16.6${}_{-0.5}^{+0.6}$ | 2.8${}_{-0.5}^{+0.5}$ | 4.1—8.4 |  $<$0.27 |  $<$0.26
I18306-0835 MM2 | 16.4${}_{-2.9}^{+3.8}$ | 10.4${}_{-1.2}^{+1.6}$ |  $<$5.6 | 4.0${}_{-0.3}^{+0.4}$ | 1.6${}_{-1.2}^{+0.9}$ |  $<$3.5 |  $<$0.60 |  $<$1.39
I18306-0835 MM3 | 13.4${}_{-1.7}^{+2.2}$ | 4.3${}_{-0.3}^{+0.4}$ |  $<$4.2 | 2.8${}_{-0.1}^{+0.2}$ | 2.7${}_{-1.1}^{+0.7}$ |  $<$3.3 |  $<$1.05 |  $<$0.26
I18337-0743 MM1 | 17.1${}_{-0.9}^{+1.0}$ | 67.2${}_{-2.4}^{+2.6}$ |  $<$4.7 | 41.1${}_{-1.1}^{+1.2}$ | 4.6${}_{-0.7}^{+0.6}$ | 4.8—9.8 |  $<$0.07 |  $<$0.12
I18337-0743 MM2 | 17.1${}_{-1.8}^{+2.2}$ | 21.5${}_{-1.5}^{+1.8}$ |  $<$4.6 | 11.9${}_{-0.6}^{+0.8}$ | 4.1${}_{-1.2}^{+1.0}$ |  $<$1.9 |  $<$0.23 |  $<$0.16
I18337-0743 MM3 | 15.0${}_{-1.4}^{+1.6}$ | 19.1${}_{-1.1}^{+1.3}$ |  $<$4.6 | 9.8${}_{-0.4}^{+0.5}$ | 2.5${}_{-0.9}^{+0.8}$ | 3.2—6.5 |  $<$0.25 |  $<$0.29

Table 11: Integrated Intensities and rotation temperature of the CH3OH $J$=7–6 line.aaThe quoted errors denote one standard deviation. Velocity range for integration is $\pm 5$ km s-1 centered at the $LSR$ velocity of N2H+ $J$=1–0 or NH3 (1, 1). Source |  $7_{-1}$–$6_{-1}$ $E$ |  $7_{1}$–$6_{1}$ $E$ |  $7_{2}$–$6_{2}$ $E$ |  $7_{0}$–$6_{0}$ $E$ | $T_{\rm rot}$
---|---|---|---|---|---
| [K km s-1] | [K km s-1] | [K km s-1] | [K km s-1] | [K]
G019.27+0.07 MM1 | 3.2 (0.2) |  $<$0.4 | 0.7 (0.1) | 1.7 (0.2) | 7.3 (0.8)
G022.35+00.41 MM1 | 2.9 (0.2) | 0.5 (0.1) | 0.7 (0.1) | 1.1 (0.2) | 8.4 (0.3)
G023.60+00.00 MM1 | 3.6 (0.2) |  $<$0.4 | 0.5 (0.1) | 0.9 (0.2) | 6.9 (0.6)
G023.60+00.01 MM2 | 2.4 (0.2) |  $<$0.3 |  $<$0.3 |  $<$0.5 |  $<$7.4
G024.33+00.11 MM1 | 2.9 (0.2) |  $<$0.4 | 1.0 (0.1) | 2.3 (0.2) | 8.3 (2.4)
G024.60+00.08 MM1 | 1.9 (0.2) |  $<$0.4 | 0.5 (0.1) | 0.6 (0.2) | 9.2 (1.1)
G034.43+00.24 MM1 | 8.7 (0.1) | 2.5 (0.1) | 3.4 (0.1) | 5.4 (0.1) | 10.9 (1.2)
G034.43+00.25 MM2 | 6.8 (0.2) | 1.2 (0.1) | 1.6 (0.1) | 3.1 (0.2) | 8.3 (0.5)
G034.43+00.26 MM3 | 6.3 (0.1) | 0.7 (0.1) | 1.2 (0.1) | 2.7 (0.1) | 7.0 (0.5)
G034.43+00.27 MM4 | 2.8 (0.2) |  $<$0.4 | 0.7 (0.1) |  $<$0.5 | 9.3 (3.1)
I18102-1800 MM1 | 4.5 (0.1) | 0.4 (0.1) | 1.0 (0.1) | 1.5 (0.1) | 7.3 (1.0)
I18151-1208 MM1 | 1.6 (0.2) |  $<$0.4 | 0.8 (0.1) | 0.9 (0.2) | 12.1 (0.8)
I18151-1209 MM2 | 4.3 (0.2) |  $<$0.4 | 1.8 (0.1) | 2.7 (0.2) | 8.1 (2.8)
I18182-1433 MM1 | 2.0 (0.2) | 0.8 (0.1) | 0.8 (0.1) | 1.5 (0.2) | 12.4 (3.5)
I18223-1245 MM3 | 1.3 (0.1) | 0.3 (0.1) |  $<$0.3 | 0.4 (0.1) | 9.5 (2.5)
I18306-0835 MM1 | 1.8 (0.2) | 0.5 (0.1) | 0.6 (0.1) | 0.9 (0.2) | 10.2 (1.1)
I18337-0743 MM1 | 1.8 (0.1) |  $<$0.4 |  $<$0.4 | 0.5 (0.1) | 8.6 (1.9)
I18337-0745 MM3 | 1.7 (0.1) | 0.3 (0.1) |  $<$0.3 | 0.6 (0.1) | 8.2 (1.2)