# Astrochemical Properties of Planck Cold Clumps

Ken'Ichi Tatematsu, Tie Liu, Satoshi Ohashi, Patricio Sanhueza, Quang Nguyen Lu'O'Ng, Tomoya Hirota, Sheng-Yuan Liu, Naomi Hirano, Minho Choi, Miju Kang, et al.

► To cite this version:

Ken'Ichi Tatematsu, Tie Liu, Satoshi Ohashi, Patricio Sanhueza, Quang Nguyen Lu'O'Ng, et al. Astrochemical Properties of Planck Cold Clumps. The Astrophysical Journal Supplement Series, 2017, 228, 10.3847/1538-4365/228/2/12. insu-03677081

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Astrochemical Properties of Planck Cold Clumps

Ken'ichi Tatematsu<sup>1,2</sup>, Tie Liu<sup>3</sup>, Satoshi Ohashi<sup>4</sup>, Patricio Sanhueza<sup>1</sup>, Quang Nguyễn Lu'o'ng<sup>1,3</sup>, Tomoya Hirota<sup>1,2</sup>, Sheng-Yuan Liu<sup>5</sup>, Naomi Hirano<sup>5</sup>, Minho Choi<sup>3</sup>, Miju Kang<sup>3</sup>, Mark A.Thompson<sup>6</sup>, Gary Fuller<sup>7</sup>, Yuefang Wu<sup>8</sup>, Di Li<sup>9</sup>, James Di Francesco<sup>10,11</sup>, Kee-Tae Kim<sup>3</sup>, Ke Wang<sup>12</sup>, Isabelle Ristorcelli<sup>13</sup>, Mika Juvela<sup>14</sup>, Hiroko Shinnaga<sup>15</sup>, Maria Cunningham<sup>16</sup>, Masao Saito<sup>17</sup>, Jeong-Eun Lee<sup>18</sup>, L. Viktor Tóth<sup>19</sup>, Jinhua He<sup>20,21,22</sup>, Takeshi Sakai<sup>23</sup>, Jungha Kim<sup>18</sup>
(JCMT Large Program "SCOPE" collaboration)
and

(TRAO Key Science Program “TOP” collaboration)

<sup>1</sup> National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan; k.tatematsu@nao.ac.jp

<sup>2</sup> Department of Astronomical Science, SOKENDAI (The Graduate University for Advanced Studies), 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan

<sup>3</sup> Korea Astronomy and Space Science Institute, Daedeokdaero 776, Yuseong, Daejeon 305-348, Korea

<sup>4</sup> Department of Astronomy, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan

<sup>5</sup> Academia Sinica Institute of Astronomy and Astrophysics, 11F of Astronomy-Mathematics Building, AS/NTU. No.1, Section 4, Roosevelt Rd, Taipei 10617, Taiwan, R.O.C.

<sup>6</sup> Centre for Astrophysics Research, Science & Technology Research Institute, University of Hertfordshire, Hatfield, AL10 9AB, UK

<sup>7</sup> Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester, M13 9PL, UK

<sup>8</sup> Department of Astronomy, Peking University, 100871, Beijing, China

<sup>9</sup> National Astronomical Observatories, Chinese Academy of Sciences, Beijing, 100012, China

<sup>10</sup> NRC Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7, Canada

<sup>11</sup> Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 1A1, Canada

<sup>12</sup> European Southern Observatory, Germany

<sup>13</sup> IRAP, CNRS (UMR5277), Universite Paul Sabatier, 9 avenue du Colonel Roche, BP 44346, F-31028, Toulouse Cedex 4, France

<sup>14</sup> Department of physics, University of Helsinki, FI-00014, Helsinki, Finland

<sup>15</sup> Department of Physics, Kagoshima University, 1-21-35, Korimoto, Kagoshima, 890-0065, Japan

<sup>16</sup> School of Physics, University of New South Wales, Sydney, NSW 2052, Australia

<sup>17</sup> Nobeyama Radio Observatory, National Astronomical Observatory of Japan, National Institutes of Natural Sciences, Nobeyama, Minamimaki, Minamisaku, Nagano 384-1305, Japan

<sup>18</sup> School of Space Research, Kyung Hee University, Seocheon-Dong, Giheung-Gu, Yongin-Si, Gyeonggi-Do, 446-701, Korea

<sup>19</sup> Department of Astronomy, Eötvös Loránd Unviersity, Pázmany Péter sétny 1, 1117 Budapest, Hungary

<sup>20</sup> Key Laboratory for the Structure and Evolution of Celestial Objects, Yunnan Observatories, Chinese Academy of Sciences, P.O. Box 110, Kunming, 650011, Yunnan Province, China

<sup>21</sup> Chinese Academy of Sciences, South America Center for Astrophysics (CASSACA), Camino El Observatorio 1515, Las Condes, Santiago, Chile

<sup>22</sup> Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile

<sup>23</sup> Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan

*Received 2016 October 11; revised 2016 November 30; accepted 2016 December 1; published 2017 March 1*

Abstract

We observed 13 Planck cold clumps with the James Clerk Maxwell Telescope/SCUBA-2 and with the Nobeyama 45 m radio telescope. The $N_2H^+$ distribution obtained with the Nobeyama telescope is quite similar to SCUBA-2 dust distribution. The 82 GHz HC<sub>3</sub>N, 82 GHz CCS, and 94 GHz CCS emission are often distributed differently with respect to the $N_2H^+$ emission. The CCS emission, which is known to be abundant in starless molecular cloud cores, is often very clumpy in the observed targets. We made deep single-pointing observations in DNC, HN<sup>13</sup>C, $N_2D^+$, and cyclic-C<sub>3</sub>H<sub>2</sub> toward nine clumps. The detection rate of $N_2D^+$ is 50%. Furthermore, we observed the NH<sub>3</sub> emission toward 15 Planck cold clumps to estimate the kinetic temperature, and confirmed that most targets are cold (≤20 K). In two of the starless clumps we observed, the CCS emission is distributed as it surrounds the $N_2H^+$ core (chemically evolved gas), which resembles the case of L1544, a prestellar core showing collapse. In addition, we detected both DNC and $N_2D^+$. These two clumps are most likely on the verge of star formation. We introduce the chemical evolution factor (CEF) for starless cores to describe the chemical evolutionary stage, and analyze the observed Planck cold clumps.

**Key words:** ISM: clouds – ISM: molecules – ISM: structure – stars: formation

1. Introduction

On the basis of the Planck all-sky survey (Planck Collaboration XXIII 2011; Planck Collaboration XXVIII 2016), we are carrying out a series of observations of molecular clouds as the Planck cold clump collaboration in order to understand the initial condition for star formation (Liu et al. 2015). Planck cold clumps have low dust temperatures (10–20 K; median = 14.5 K). Pilot observations have been carried out

with various ground-based telescopes such as the James Clerk Maxwell Telescope (JCMT), IRAM, PMO 14 m, APEX, Mopra, Effelsberg, CSO, and SMA (Liu et al. 2015). A Large Program for JCMT dust continuum observations with SCUBA-2 (SCOPE<sup>24</sup>: SCUBA-2 Continuum Observations of Pre-protostellar Evolution; M. A. Thompson et al. 2017, in

<footnote n="24"><sup>24</sup> https://www.eaobservatory.org/jcmt/science/large-programs/scope/</footnote>
preparation) and a Key Science Program with TRAO 14 m
radio telescope (TOP<fnref n="25" />: TRAO Observations of Planck cold
clumps; T. Liu et al. 2017, in preparation) are ongoing.

To characterize Planck cold clumps, it is essential to
investigate their chemical and physical properties in detail. In
particular, we try to make their evolutionary stages clear. The
chemical evolution of molecular clouds has been established to
some extent, not only for nearby dark clouds (e.g., Suzuki et al.
1992; Hirahara et al. 1992; Benson et al. 1998; Hirota &
Yamamoto 2006; Hirota et al. 2009), but also for giant molecular
clouds (GMCs; Tatematsu et al. 2010, 2014b; Ohashi et al. 2014
for Orion A GMC; Ohashi et al. 2016a for Vela C GMC;
Sanhueza et al. 2012; Hoq et al. 2013 for infrared dark clouds).
Carbon-chain molecules such as CCS and HC₃N tend to be
abundant in starless molecular cloud cores, while N-bearing
molecules such as NH₃ and N₂H⁺ as well as cyclic-C₃H₂
(c-C₃H₂) tend to be abundant in star-forming molecular cloud
cores. However, N₂H⁺ will be destroyed by evaporated CO in
warm cores having T_dust > 25 K (Lee et al. 2004), and therefore
N(N₂H⁺)/N(CCS) may not be a good evolutionary tracer for
T_dust > 25 K. In a survey of nearby cold dark cloud cores,
Suzuki et al. (1992) detected CCS at 45 GHz in 55% of the
observed cores, and found that CCS is a tracer of the young
molecular gas in starless cloud cores. Tatematsu et al. (2010)
detected CCSJ_N = 4₃ – 3₂ at 45 GHz in 32% of the cores
observed toward Orion A GMC. Sakai et al. (2008) observed 55
massive clumps associated with infrared dark clouds (IRDCs) in
CCS J_N = 4₃ – 3₂ at 45 GHz using the Nobeyama 45 m
telescope, and detected this line in none of them. Dirienzo
et al. (2015) observed nine IRDCs in CCS J_N = 2₁ – 1₀ at
24 GHz using VLA, and detected this line in all of them.

Furthermore, deuterium fractionation ratios are powerful
evolutionary tracers (Hirota & Yamamoto 2006; Sakai et al.
2012). The deuterium fraction D/H in molecules in molecular
clouds is larger than the terrestrial abundance ratio
(1.15 × 10⁻⁴) or the protosolar estimate (2 × 10⁻⁵) (Geiss
& Reeves 1981). The deuterium fraction is enhanced in
molecular cloud cores before star formation (prestellar phase),
which is cold enough, and the ratio increases with prestellar
evolution until star formation (Crapsi et al. 2005; Hirota &
Yamamoto 2006). However, it should be noted that the
deuterium fraction decreases with increasing temperature (Snell
& Wootten 1979; Wootten 1987; Schilke et al. 1992;
Tatematsu et al. 2010). After star formation, the deuterium
fraction decreases (Emprechtinger et al. 2009). N(DNC)/N
(HNC) will decrease, which may in part be due to an increase
in the kinetic temperature, but may be affected by a larger
reaction timescale (several times 10⁴ years) while N(N₂D⁺)/N
(N₂H⁺) will reflect the current temperature more directly,
because of a shorter reaction timescale (less than 100 years)
(Sakai et al. 2012).

We investigate the evolutionary stages of Planck cold
clumps using molecular column density ratios. For this
purpose, by using the Nobeyama 45 m telescope, we observed
13 Planck cold clumps, for which we have already obtained
accurate positions from preliminary IRAM 30 m observations
in N₂H⁺ and/or SCUBA-2 observations. We selected sources
whose C¹⁸O J = 1–0 linewidths are relatively narrow (<1.5
km s⁻¹) from the previous observations with the 13.7 m
telescope of the Purple Mountain Observatory (PMO) at De

Ling Ha, because we prefer to observe relatively close objects
to investigate the chemical differentiation on scales of
0.05–0.1 pc (Ohashi et al. 2014, 2016a; Tatematsu et al.
2014b). However, some of our sources (G108.8-00.8 and
G120.7+2.7) are actually distant (1–3.5 kpc), which needs
some care in discussion based on the column density ratios.
While we focus on the chemical evolution stage as the main
target of the current study, we also briefly investigate the
physical properties of the sources by analyzing the specific
angular momenta.

**2. Observations**

2.1. James Clerk Maxwell Telescope

Observations with the 15 m JCMT on Mauna Kea were
made between 2014 November and 2015 December in the pilot
survey phase (project IDs: M15AI05, M15BI061) of the JCMT
legacy survey program “SCOPE.” The Submillimetre Com-
mon-User Bolometer Array 2 (SCUBA-2) was employed for
observations of the 850 µm continuum. It is a 10,000 pixel
bolometer camera operating simultaneously at 450 and 850
µm. Observations were carried out in constant velocity (CV)
Daisy mode under grade 3/4 weather conditions with a
225 GHz opacity between 0.1 and 0.15. The mapping area is
about 12' × 12'. The beam size of SCUBA-2 at 850 µm is
~14". The typical rms noise level of the maps is about 6–10
mJy beam⁻¹ in the central 3' area, and increases to
10–30 mJy beam⁻¹ out to 12'. The data were reduced using
SMURF in the STARLINK package.

## 2.2. Nobeyama 45 m Telescope

Observations with the 45 m radio telescope of Nobeyama
Radio Observatory<fnref n="26" /> were carried out from 2015 December to
2016 February. We observed eight molecular lines by using the
receivers TZ1 and T70 (Table 1). Observations with the
receiver TZ1 (we used one beam called TZ1 out of two beams
of the receiver TZ) (Asayama & Nakajima 2013; Nakajima
et al. 2013) were made to simultaneously observe four
molecular lines, 82 GHz CCS, 94 GHz CCS, HC₃N, and
N₂H⁺. Observations were carried out with T70 to simulta-
neously observe four other lines, HN¹³C, DNC, N₂D⁺, and
c-C₃H₂. TZ1 and T70 are double-polarization, two-sideband
SIS receivers. Molecular transitions are selected to achieve a
high angular resolution of ~20" to differentiate the distribution
of molecules, and they are detectable even from cold gas
(~20 K). The upper energy level E_u of the observed transitions
are listed in Table 1.

The full width at half maximum (FWHM) beam sizes at
86 GHz with TZ1 and T70 were 18.2 ± 0.1 and 18.8 ± 0.3,
respectively. The main-beam efficiency η<sub>mb</sub> at 86 GHz with
TZ1 was 54 ± 3% and 53 ± 3% in H and V polarizations,
respectively. The efficiencies with T70 was 54 ± 3% and
55 ± 3% in H and V polarizations, respectively. We also
observed NH₃ (J, K) = (1, 1) at 23.694495 GHz (Ho &
Townes 1983) in both circular polarizations with the receiver
H22. The FWHM beam size at 23 GHz with H22 was 74.4 ±
0.3 and 73.9 ± 0.3 for ch1 and ch2 (right-handed and left-
handed circular polarization), respectively. The main-beam
efficiency η<sub>mb</sub> at 23 GHz with H22 was 83 ± 4% and

<footnote n="25">²⁵ http://radio.kasi.re.kr/trao/key_science.php</footnote>

<footnote n="26">²⁶ Nobeyama Radio Observatory is a branch of the National Astronomical Observatory of Japan, National Institutes of Natural Sciences.</footnote>
<table><caption>**Table 1**
Observed Lines</caption><thead><tr><th>Line</th><th>Frequency</th><th>Frequency Reference</th><th>Upper Energy Level E<sub>u</sub></th><th>Receiver</th><th>Observing Mode</th></tr></thead><tbody><tr><td>CCS J<sub>N</sub> = 7<sub>6</sub> – 6<sub>5</sub></td><td>81.505208 GHz</td><td>Cummins et al. (1986)</td><td>15.3 K</td><td>TZ1</td><td>OTF</td></tr><tr><td>CCS J<sub>N</sub> = 8<sub>7</sub> – 6<sub>5</sub></td><td>93.870107 GHz</td><td>Yamamoto et al. (1990)</td><td>19.9 K</td><td>TZ1</td><td>OTF</td></tr><tr><td>HC<sub>3</sub>N J = 9–8</td><td>81.8814614 GHz</td><td>Picket et al. (1998)</td><td>19.7 K</td><td>TZ1</td><td>OTF</td></tr><tr><td>N<sub>2</sub>H<sup>+</sup> J = 1–0</td><td>93.1737767 GHz</td><td>Caselli & Myers (1995)</td><td>4.5 K</td><td>TZ1</td><td>OTF</td></tr><tr><td>DNC J = 1–0</td><td>76.3057270 GHz</td><td>Picket et al. (1998)</td><td>3.7 K</td><td>T70</td><td>single pointing</td></tr><tr><td>HN<sup>13</sup>C J = 1–0</td><td>87.090859 GHz</td><td>Frerking et al. (1979)</td><td>4.2 K</td><td>T70</td><td>single pointing</td></tr><tr><td>N<sub>2</sub>D<sup>+</sup> J = 1–0</td><td>77.1096100 GHz</td><td>Picket et al. (1998)</td><td>3.7 K</td><td>T70</td><td>single pointing</td></tr><tr><td>c-C<sub>3</sub>H<sub>2</sub> J<sub>K<sub>u</sub>K<sub>e</sub></sub> = 2<sub>12</sub>–1<sub>01</sub></td><td>85.338906 GHz</td><td>Thaddeus et al. (1981)</td><td>4.1 K</td><td>T70</td><td>single pointing</td></tr><tr><td>NH<sub>3</sub> (J, K) = (1, 1)</td><td>23.694495 GHz</td><td>Ho & Townes (1983)</td><td>23.4 K</td><td>H22</td><td>single pointing</td></tr></tbody></table>

84 ± 4%, for ch1 and ch2, respectively. The receiver backend was the digital spectrometer “SAM45.” The spectral resolution was 15.26 kHz (corresponding to 0.05–0.06 km s⁻¹) for TZ1 and T70, and 3.81 kHz (corresponding to ~0.05 km s⁻¹) for H22.

Observations with receiver TZ1 were conducted in the on-the-fly (OTF) mapping mode (Sawada et al. 2008) with data sampling intervals along a strip of 5" and separations between strips of 5". We have made orthogonal scans in R.A. and Decl. to minimize scan effects. Observations with receivers T70 and H22 were carried out in the ON-OFF position-switching mode. The ON positions with receiver T70 were determined from possible intensity peaks in N₂H⁺ on temporal lower-S/N-ratio TZ1 maps during observations (before completion), but are not necessarily intensity peaks in N₂H⁺ on the final maps. In addition, the T70 position of G207N was incorrect.

Coordinates used for the observations are listed in Table 2. The distances to the sources are taken from Ramirez Alegria et al. (2011) for G108.8-00.8, Wu et al. (2012) for G120.7+2.7, Lombardi et al. (2010) for G157.6-12.2, Loinard et al. (2007) and Lombardi et al. (2010) for G174.0-15.8, Kim et al. (2008) for G192.33-11.88, G202.31-8.92, G204.4-11.3, and G207.3-19.8, and Clariá (1974) for G224.4-0.6. The distances to G089.9-01.9, G149.5-1.2, and G202.00+2.65 are taken from Planck Collaboration XXVIII (2016).

The observed intensity is reported in terms of the corrected antenna temperature $T_A^*$. To derive the physical parameters, we use the main-beam radiation temperature $T_{mb} = T_A^*/\eta_{mb}$. The telescope pointing was established by observing relevant 43-GHz SiO maser sources every ~60 minutes for TZ1 and T70 observations, and was accurate to ~5". For H22 observations, pointing was established once a day in the beginning of observations. The observed data were reduced using the software package “NoStar” and “NewStar” of Nobeyama Radio Observatory.

### 3. Results

Figures 1 through 13 show the maps obtained with JCMT/SCUBA-2 and with the Nobeyama 45 m telescope. Table 3 lists the dense cores detected with JCMT/SCUBA-2, their intensities, and column densities. The column density is derived by using Equation (A.27) in Kauffmann (2007). Associations of young stars are investigated on the basis of WISE 22 µm, Akari, Spitzer images, and IRAS point source catalog, and they are classified through their spectral indexes (Liu et al. 2016, in preparation). N₂H⁺ was detected for all sources, and we detected 81 GHz CCS from 7 out of 13. Tables 4 and 5 summarize observed parameters from

Nobeyama 45 m telescope receiver TZ1. The emission line spectra have a single velocity component, when they are detected, and there is no position showing two velocity components. For Table 5, we should note that T70 positions do not necessarily coincide with the final N₂H⁺ peaks as intended. The line parameters are obtained through Gaussian fitting (either single-component Gaussian or hyperfine fitting). The upper limit to the intensity is defined as 3σ, where σ is the rms noise level at 1 km s⁻¹ bin.

Tables 6 summarizes the observed parameters from the Nobeyama 45 m telescope receiver T70. Again, emission line spectra have single velocity component, when they are detected, and there is no position showing two velocity components. We detected DNC, HN¹³C, c-C₃H₂ all but G108N and G207N (again, G207N position was mistakenly set). The N₂D⁺ hyperfine transitions were detected toward four out of eight sources (excluding G207N).

Furthermore, we observed 15 sources with the Nobeyama 45 m telescope receiver H22 in NH₃ transitions in single-pointing observations. Nine out of them were detected in (J, K) = (2, 2), and we derived $T_{rot}$. The NH₃ rotation temperature $T_{rot}$ is derived as explained in Ho & Townes (1983), and then converted to the gas kinetic temperature $T_k$ by using the relation by Tafalla et al. (2004). Observed intensities, derived $T_{rot}$ and $T_k$ are summarized in Table 7.

We investigate the molecular line intensity distribution shown in Figures 1 to 13. In general, the N₂H⁺ distribution (black contours in panel (b)) is quite similar to the 850 µm dust continuum emission distribution (contours in panel (a); gray-scale in panels (b) and (c)). The 82 GHz CCS emission (blue contours) is clumpy in general, and is often located at the edge of the N₂H⁺/850 µm core or is distributed as it surrounds the N₂H⁺/850 µm core. We draw the 2.5σ contour in some cases to let the reader understand the reliability of the 3σ contour as detection. Most clumps are as cold as 10–20 K, and therefore the depletion of CCS can contribute to a configuration of the N₂H⁺ core being surrounded by CCS (Aikawa et al. 2001; Bergin et al. 2002). The 94 GHz CCS emission, when detected, does not necessarily follow that of the 82 GHz CCS emission, although the upper energy levels of these transitions do not differ so much. Taking the beamsizes of JCMT/SCUBA-2 and the Nobeyama 45 m telescope and the pointing accuracy of the latter telescope, only differences in the spatial distribution larger than 10" will be meaningful.

The molecular column density is calculated by assuming local thermodynamic equilibrium (LTE) as explained in, e.g., Suzuki et al. (1992), Mangum & Shirley (2015), Sanhueza et al. (2012). N₂H⁺, N₂D⁺, and NH₃ have hyperfine transitions, and we can derive the excitation temperatures $T_{ex}$ directly from
<table><caption>Table 2
Coordinates for the Observations</caption><thead><tr><th rowspan="2">Source</th><th colspan="2">OTF Reference Center</th><th rowspan="2">OTF area</th><th colspan="2">T70</th><th colspan="2">H22</th><th colspan="2">OFF</th><th rowspan="2">Distance<br>(kpc)</th></tr><tr><th>R.A.(J2000.0)</th><th>Decl.(J2000.0)</th><th>R.A.(J2000.0)</th><th>Decl.(J2000.0)</th><th>R.A.(J2000.0)</th><th>Decl.(J2000.0)</th><th>R.A.(J2000.0)</th><th>Decl.(J2000.0)</th></tr></thead><tbody><tr><td>G089.9-01.9</td><td>21:20:04.35</td><td>46:54:46.8</td><td>2' x 2'</td><td>21:20:04.35</td><td>46:54:46.8</td><td>21:20:04.35</td><td>46:54:46.8</td><td>21:19:20</td><td>46:54:00</td><td>0.62</td></tr><tr><td>G108.8-00.8N (G108N)</td><td>22:58:56.2</td><td>58:58:21.7</td><td>2' x 2'</td><td>22:58:53.6</td><td>58:58:21.7</td><td>22:58:56.2</td><td>58:58:21.7</td><td>22:58:15</td><td>59:01:00</td><td>3.2</td></tr><tr><td>G108.8-00.8S (G108S)</td><td>22:58:40.8</td><td>58:55:34.4</td><td>2' x 2'</td><td>...</td><td>...</td><td>22:58:40.8</td><td>58:55:34.4</td><td>22:58:15</td><td>59:01:00</td><td>3.2</td></tr><tr><td>G120.7+2.7N (G120N)</td><td>00:29:26.11</td><td>65:27:14.3</td><td>2' x 2'</td><td>00:29:29.3</td><td>65:27:14.3</td><td>00:29:26.11</td><td>65:27:14.3</td><td>00:29:20</td><td>65:20:00</td><td>1.82</td></tr><tr><td>G120.7+2.7S (G120S)</td><td>00:29:46.76</td><td>65:25:47.8</td><td>2' x 2'</td><td>...</td><td>...</td><td>00:29:46.76</td><td>65:25:47.8</td><td>00:29:20</td><td>65:20:00</td><td>1.82</td></tr><tr><td>G149.5-1.2</td><td>03:56:53</td><td>51:48:00</td><td>3' x 3'</td><td>03:56:57.3</td><td>51:49:00</td><td>03:56:57.3</td><td>51:49:00</td><td>03:56:15</td><td>51:44:00</td><td>0.84</td></tr><tr><td>G157.6-12.2</td><td>03:51:53.6</td><td>38:15:22.6</td><td>2' x 2'</td><td>03:51:53.6</td><td>38:15:22.6</td><td>03:51:53.6</td><td>38:15:22.6</td><td>03:51:20</td><td>38:10:00</td><td>0.45</td></tr><tr><td>G174.0-15.8</td><td>04:32:45.30</td><td>24:21:51.7</td><td>2' x 2'</td><td>...</td><td>...</td><td>04:32:45.30</td><td>24:21:51.7</td><td>04:33:09.19</td><td>24:23:42.7</td><td>0.15</td></tr><tr><td>G192.33-11.88</td><td>05:29:54.16</td><td>12:16:53.0</td><td>2' x 2'</td><td>05:29:54.16</td><td>12:16:53.0</td><td>05:29:54.16</td><td>12:16:53.0</td><td>05:30:05</td><td>12:10:00</td><td>0.42</td></tr><tr><td>G202.00+2.65</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>06:40:55.10</td><td>10:56:16.2</td><td>06:40:43.93</td><td>11:01:40.8</td><td>0.76</td></tr><tr><td>G202.31-8.92</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>06:00:10.0</td><td>05:15:00.0</td><td>06:00:18</td><td>05:20:00</td><td>0.42</td></tr><tr><td>G204.4-11.3</td><td>05:55:38.54</td><td>02:11:35.6</td><td>2' x 2'</td><td>05:55:38.54</td><td>02:11:35.6</td><td>05:55:38.54</td><td>02:11:35.6</td><td>05:55:48.98</td><td>02:05:37.0</td><td>0.42</td></tr><tr><td>G207.3-19.8N (G207N)</td><td>05:30:48</td><td>-04:11:30</td><td>4' x 4'</td><td>05:30:48.5</td><td>-04:09:40.0</td><td>05:30:46.5</td><td>-04:10:30</td><td>05:31:35</td><td>-04:12:22</td><td>0.42</td></tr><tr><td>G207.3-19.8S (G207S)</td><td>05:31:03.00</td><td>-04:16:20</td><td>4' x 4'</td><td>...</td><td>...</td><td>05:31:03.00</td><td>-04:17:05.3</td><td>05:31:35</td><td>-04:12:22</td><td>0.42</td></tr><tr><td>G224.4-0.6</td><td>07:10:03.83</td><td>-10:31:28.21</td><td>2' x 2'</td><td>07:09:59.8</td><td>-10:31:18.2</td><td>07:10:01.12</td><td>-10:30:58.2</td><td>07:09:55</td><td>-10:28:00</td><td>1.1</td></tr></tbody></table>

Note. Three dots means "not observed."
<figure><img src="image_3.png" /><figcaption>**Figure 1.** (a) The 850 µm continuum image (contours) obtained toward G089.9-01.9 superimposed on the WISE 22 µm image (color). Contour levels are [0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 235.7 mJy/beam. The magenta cross symbol represents the SCUBA-2 peak position (Table 3). The dark brown filled circle represents the half-power beam size for JCMT/SCUBA-2 850 µm. (b) Black and red contour maps represent N<sub>2</sub>H<sup>+</sup> and HC<sub>3</sub>N integrated intensity maps, respectively, while the gray-scale map represents the 850 µm continuum intensity. The N<sub>2</sub>H<sup>+</sup> integrated intensity is calculated for the main hyperfine component group F<sub>1</sub> = 2–1 (F = 1–0, 2–1, and 3–2) from a velocity range of 0.5 to 3.5 km s<sup>-1</sup> with levels of [3, 6, 9, 12, 15] × 0.092 K km s<sup>-1</sup>(1σ). The HC<sub>3</sub>N intensity is calculated from a velocity range of 0.5 to 3.5 km s<sup>-1</sup> with levels of [3, 4.5, 6, 7.5, 10] × 0.081 K km s<sup>-1</sup>(1σ). The black and red filled circles represent the half-power beam sizes for N<sub>2</sub>H<sup>+</sup> and HC<sub>3</sub>N, respectively. (c) Blue and green contours represent the 82 GHz CCS and 94 GHz CCS integrated intensity maps, respectively, while the grayscale map represents the 850 µm continuum intensity. The 82 GHz CCS intensity is calculated from a velocity range of 0.5 to 3.5 km s<sup>-1</sup> with levels of [2.5, 3, 3.5, 4] × 0.080 K km s<sup>-1</sup>(1σ). The 94 GHz CCS intensity is calculated from a velocity range of 0.5 to 3.5 km s<sup>-1</sup> with levels of [2.5, 3, 3.5, 4] × 0.11 K km s<sup>-1</sup>(1σ). The blue and green filled circles represent the half-power beam sizes for 82 GHz CCS and 94 GHz CCS, respectively.</figcaption></figure>

observations. We assume that the beam filling factor is unity. If the filling factor is lower than unity, we underestimate $T_{ex}$. $T_{ex}$ from N<sub>2</sub>H<sup>+</sup> ranges from 3.7 to 5.7 K. When we compared $T_{ex}$ for N<sub>2</sub>H<sup>+</sup> with $T_K$ derived from NH<sub>3</sub> observations, we obtain a relation of $T_{ex} = 0.45 \pm 0.27$ $T_K$. We assume that the excitation temperatures $T_{ex}$ for the other molecular lines are 0.5 $T_K$, assuming that the levels are subthermally excited to 50% (for G207N, we assume $T_{ex} = 0.6$ $T_K$ so that the observed intensity can be explained in LTE). If $T_k$ is an upper limit, we assume $T_k = 10$ K. The necessary parameters for CCS are taken from Yamamoto et al. (1990) and references therein. For N<sub>2</sub>H<sup>+</sup>, if the hyperfine fitting is unsuccessful, we try to calculate the column density by using the velocity-integrated intensity of a main $F_1 = 2–1$ group of the three hyperfine components ($F = 1–0, 2–1$, and 3–2), by assuming optically thin emission, and by neglecting the background term.

We show in Table 8 the column density range by assuming that the actual column density is a factor of 1–10 larger than the optically thin estimate. The resulting column densities are listed in Tables 8 and 9. Although we observed the 94 GHz CCS emission, the detection rate is not high. At T70 positions, only two clumps were detected but the S/N ratio is low. We decided to use $T_k$ to estimate $T_{ex}$ (CCS) instead of the excitation analysis (e.g., Large Velocity Gradient models) to treat all the data in a consistent way. Tables 10 and 11 list the fractional abundance X of molecules relative to H<sub>2</sub> calculated from the column density ratio toward the JCMT/SCUBA-2 peaks and T70 positions, respectively. The H<sub>2</sub> column density is taken from the dust continuum flux density measured toward the T70 position.

In the next section, we introduce the results for individual sources.

# 4. Individual Objects

## 4.1. G089.9-01.9

The object is located in L974 (Lynds 1962; Dobashi et al. 2005), and in the dark cloud Khavtassi 137 (Khavtassi 1960). There is a Class 0 like source (IRAS 21182+4611),

which is a bright source in the WISE image, northeast of the western core G089W with an offset of ~15". Then, we regard G089W itself as starless. To our knowledge, there is no information that the eastern core G089E is associated with any young stellar object, and we also regard it as starless. Figure 1 shows maps toward G089.9-01.9. The N<sub>2</sub>H<sup>+</sup> distribution shows a resemblance to the 850 µm distribution, but their peak positions are slightly different. The HC<sub>3</sub>N distribution shows some similarity to the 850 µm distribution, but the correlation between their intensities is poor. The 82 GHz CCS distribution is very clumsy, and appears as if it surrounds the 850 µm core. The 94 GHz CCS distribution is different, but it is still located on both sides of the 850 µm core. Nobeyama T70 observations were made toward G089W. The column density ratio of N(DNC) to N(HN<sup>13</sup>C) is 4.5, which is close to the value of 3.0 at L1544 (Hirota et al. 2003; Hirota & Yamamoto 2006). L1544 is known as a prestellar core showing collapsing motion (Tafalla et al. 1998).

## 4.2. G108.8-00.8

G108.8-00.8 is located in a GMC (1° × 15') associated with five Sharpless (1959) HII regions, S147, S148, S149, S152, and S153, and also associated with the supernova remnant G109.1-1.0 (CTB109) in the Perseus arm (Tatematsu et al. 1985, 1987). These two cores are located between peaks α (corresponding to S152) and ζ in Tatematsu et al. (1985). G108.8-00.8S is associated with two Class I-like sources seen in the WISE image, while G108.8-00.8N is starless. Figure 2 shows maps toward G108.8-00.8. The N<sub>2</sub>H<sup>+</sup> distribution resembles the 850 µm distribution. The HC<sub>3</sub>N emission is observed at the edge of the 850 µm core of G108N, and the correlation between N<sub>2</sub>H<sup>+</sup> and HC<sub>3</sub>N is poor. For G108S, their distributions are more or less correlated. The 82 GHz CCS emission is detected toward the N<sub>2</sub>H<sup>+</sup>/850 µm cores (G108N and G108S) and also the edge of them (G108N). Note that this source is distant, the spatial resolution is as large as 0.3 pc. It is possible that different distributions between N<sub>2</sub>H<sup>+</sup> and CCS are less clear due to its large distance. The kinetic temperature of
<table><caption>**Table 3**
Parameters of SCUBA-2 Peaks</caption><thead><tr><th>Source</th><th>SCUBA-2 peak</th><th>R.A.<br>(J2000)</th><th>Decl.<br>(J2000)</th><th>Comments</th></tr></thead><tbody><tr><td rowspan="2">G089.9-01.9</td><td>G089E</td><td>21:20:08.5</td><td>46:54:52.4</td><td>starless</td></tr><tr><td>G089W</td><td>21:20:04.4</td><td>46:54:47.4</td><td>starless? an infrared source IRAS 21182+4641 on the east</td></tr><tr><td rowspan="5">G108.8-00.8</td><td>G108N</td><td>22:58:57.5</td><td>58:58:30.2</td><td>starless</td></tr><tr><td>G108S1</td><td>22:58:40.8</td><td>58:55:02.0</td><td>starless</td></tr><tr><td>G108S2</td><td>22:58:41.1</td><td>58:55:37.1</td><td>starless</td></tr><tr><td>G108S3</td><td>22:58:38.9</td><td>58:55:48.1</td><td>Class I?</td></tr><tr><td>G108S4</td><td>22:58:34.2</td><td>58:55:48.2</td><td>Class I?</td></tr><tr><td rowspan="2">G120.7+2.7</td><td>G120S1</td><td>00:29:43.8</td><td>65:26:03.1</td><td>WISE faint source only detected at 3.4 and 4.6 micron, no AKARI source, a foreground star?</td></tr><tr><td>G120S2</td><td>00:29:38.5</td><td>65:26:17.8</td><td>starless</td></tr><tr><td rowspan="2">G149.5-1.2</td><td>G120N</td><td>00:29:29.1</td><td>65:27:18.4</td><td>starless, offset from infrared sources</td></tr><tr><td>G149N</td><td>03:56:57.2</td><td>51:48:50.0</td><td>WISE, class I?</td></tr><tr><td>G157.6-12.1</td><td>G149S</td><td>03:56:50.4</td><td>51:46:57.4</td><td>starless</td></tr><tr><td>G174.0-15.8</td><td>G174</td><td>04:32:44.9</td><td>24:21:39.6</td><td>starless</td></tr><tr><td rowspan="2">G192.33-11.88</td><td>G192N</td><td>05:29:54.5</td><td>12:16:55.0</td><td>Class 0</td></tr><tr><td>G192S</td><td>05:29:54.7</td><td>12:16:30.6</td><td>proto-brown dwarf candidate</td></tr><tr><td rowspan="3">G202.00+2.65</td><td>G202.0N</td><td>06:40:56.1</td><td>10:56:34.9</td><td>Class 0? Spitzer, Akari, WISE</td></tr><tr><td>G202.0M</td><td>06:40:55.1</td><td>10:56:16.4</td><td>starless</td></tr><tr><td>G202.0S</td><td>06:40:54.8</td><td>10:55:40.1</td><td>Class 0? Spitzer, WISE</td></tr><tr><td>G202.31-8.92</td><td>G202.3</td><td>06:00:08.8</td><td>05:14:59.6</td><td>starless</td></tr><tr><td rowspan="2">G204.4-11.3</td><td>G204NE</td><td>05:55:38.4</td><td>02:11:35.5</td><td>starless</td></tr><tr><td>G204SW</td><td>05:55:35.6</td><td>02:11:01.6</td><td>class 0?</td></tr><tr><td rowspan="6">G207N</td><td>G207N1</td><td>05:30:51.0</td><td>-04:10:36.7</td><td>class 0? HH 58? but SCUBA-2 core peak offset from infrared source</td></tr><tr><td>G207N2</td><td>05:30:50.8</td><td>-04:10:14.3</td><td>starless</td></tr><tr><td>G207N3</td><td>05:30:46.5</td><td>-04:10:29.0</td><td>starless</td></tr><tr><td>G207N4</td><td>05:30:44.7</td><td>-04:10:27.4</td><td>starless</td></tr><tr><td>G207N5</td><td>05:30:47.1</td><td>-04:12:31.3</td><td>starless</td></tr><tr><td>G207S1</td><td>G207S2</td><td>05:31:02.0</td><td>-04:14:56.6</td><td>starless</td></tr><tr><td rowspan="5">G207S</td><td>G207S3</td><td>05:31:03.7</td><td>-04:15:48.3</td><td>starless</td></tr><tr><td>G207S4</td><td>05:31:00.3</td><td>-04:15:43.6</td><td>starless</td></tr><tr><td>G207S5</td><td>05:31:03.2</td><td>-04:17:00.3</td><td>starless</td></tr><tr><td>G207S6</td><td>05:31:03.8</td><td>-04:17:37.0</td><td>starless</td></tr><tr><td>G224.4-0.6</td><td>G224S</td><td>07:10:06.2</td><td>-10:32:00.3</td><td>IRAS 07077-1026, Akari, WISE, Spitzer</td></tr><tr><td rowspan="2"></td><td>G224NE</td><td>07:10:05.6</td><td>-10:31:11.8</td><td>Akari, WISE, Spitzer</td></tr><tr><td>G224NW</td><td>07:10:00.8</td><td>-10:30:58.2</td><td>starless</td></tr></tbody></table>

G108S is 14.3 ± 3.0 K. G108S is as cold as typical cold dark clouds. Nobeyama T70 observations were made toward G108N, a starless core. We detected DNC, but not $HN^{13}C$. The column density ratio of $N(DNC)$ to $N(HN^{13}C)$ is >2.5, which is similar to the value of 3.0 at L1544 (Hirota et al. 2003; Hirota & Yamamoto 2006). Kim et al. (2016) will report our observations with other telescopes such as PMO 14 m, CSO, IRAM 30 m telescopes, etc.

### 4.3. G120.7+2.7

Figure 3 shows maps toward G120.7+2.7. The WISE source is clearly offset from G120N, and we regard the latter as a starless core. Both $N_2H^+$ and $HC_3N$ distributions are well correlated with the 850 µm distribution. In G120N, the 82 GHz CCS emission has two intensity peaks, and one of them is close to the $N_2H^+$ emission peak. Toward the $N_2H^+$ peak, we detected $N_2D^+$. In G120S, the $N_2H^+$ emission shows two cores. We clearly detected both 82 GHz and 94 GHz CCS emission at G120S. It is possible that the CCS emission surrounds the $N_2H^+$ cores, although it is less clear. Nobeyama T70 observations were made toward G120N, a starless core.

The column density ratio of $N(DNC)$ to $N(HN^{13}C)$ is 1.7, which is close to the value of 1.91 at L1498 (Hirota & Yamamoto 2006).

### 4.4. G149.5-1.2

This clump is located at the edge of the dark cloud Khavtassi 241 (Khavtassi 1960). Figure 4 shows maps toward G149.5-1.2. The $N_2H^+$ distribution is well correlated with the 850 µm distribution. The $HC_3N$ emission is poorly correlated with the 850 µm distribution, and it is located on both sides of the north-eastern 850 µm (and $N_2H^+$) core. We detected the $N_2D^+$ emission in single pointing observations between the brightest $N_2H^+$ core G149N (WISE source) and the northern $HC_3N$ core. The column density ratio of $N(DNC)$ to $N(HN^{13}C)$ is 3.2, which is close to the value of 3.0 in L1544 (Hirota et al. 2003; Hirota & Yamamoto 2006).

### 4.5. G157.6-12.2

This clump is located near the dark cloud L1449 (Lynds 1962; Dobashi et al. 2005) and in Khavtassi 257 (Khavtassi 1960), which is close to the California Nebula, NGC
<table><caption>Table 4
Intensities<sup>a</sup> Observed with the Receiver TZ1 toward the SCUBA-2 Peaks</caption><thead><tr><th rowspan="3">SCUBA-<br>2 peak</th><th colspan="3">82<br>GHz CCS</th><th colspan="3">94<br>GHz CCS</th><th colspan="3">HC<sub>3</sub>N</th><th colspan="3">N<sub>2</sub>H<sup>+</sup></th><th rowspan="2">T<sub>ex</sub></th><th rowspan="2">τ(main)</th><th rowspan="2">Integrated<br>Intensity<br>(K km s<sup>-1</sup>)</th></tr><tr><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δ<sub>V</sub><br>(km s<sup>-1</sup>)</th><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δ<sub>V</sub><br>(km s<sup>-1</sup>)</th><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δ<sub>V</sub><br>(km s<sup>-1</sup>)</th><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δ<sub>V</sub><br>(km s<sup>-1</sup>)</th></tr></thead><tbody><tr><td>G089E</td><td>0.60</td><td>1.94</td><td>0.14</td><td>0.27</td><td>1.80</td><td>0.68</td><td>0.56</td><td>1.82</td><td>0.49</td><td>0.8</td><td>1.82</td><td>0.40</td><td>4.6 ± 0.4</td><td>6.2 ± 2.0</td><td>...</td></tr><tr><td>G089W</td><td>0.51</td><td>1.31</td><td>0.33</td><td>0.43</td><td>1.43</td><td>0.42</td><td>1.08</td><td>1.29</td><td>0.47</td><td>1.1</td><td>1.50</td><td>0.63</td><td>8.7 ± 4.2</td><td>1.4 ± 1.2</td><td>...</td></tr><tr><td>G108N</td><td>0.18</td><td>-49.38</td><td>1.53</td><td>&lt;0.16</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.5</td><td>-49.40</td><td>1.20</td><td>5.8 ± 3.8</td><td>0.9 ± 1.3</td><td>...</td></tr><tr><td>G108S1</td><td>0.19</td><td>-49.00</td><td>0.78</td><td>...</td><td>...</td><td>...</td><td>0.28</td><td>-48.84</td><td>0.33</td><td>&lt;0.10</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G108S2</td><td>0.18</td><td>-49.58</td><td>1.44</td><td>...</td><td>...</td><td>...</td><td>0.22</td><td>-49.66</td><td>1.39</td><td>0.3</td><td>-49.78</td><td>1.30</td><td>3.4 ± 0.2</td><td>3.2 ± 1.5</td><td>...</td></tr><tr><td>G108S3</td><td>&lt;0.12</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.2</td><td>~50</td><td>...</td><td>...</td><td>...</td><td>0.5</td></tr><tr><td>G108S4</td><td>&lt;0.12</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.3</td><td>-51.20</td><td>1.22</td><td>3.8 ± 0.8</td><td>1.9 ± 1.9</td><td>...</td></tr><tr><td>G120S1</td><td>0.25</td><td>-18.01</td><td>1.48</td><td>0.21</td><td>-18.12</td><td>1.48</td><td>0.51</td><td>-18.22</td><td>1.27</td><td>0.6</td><td>-18.33</td><td>1.33</td><td>4.8 ± 0.6</td><td>1.9 ± 0.7</td><td>...</td></tr><tr><td>G120S2</td><td>&lt;0.14</td><td>...</td><td>...</td><td>&lt;0.15</td><td>...</td><td>...</td><td>0.79</td><td>-18.16</td><td>0.92</td><td>0.4</td><td>-18.06</td><td>0.98</td><td>3.9 ± 0.3</td><td>4.0 ± 2.0</td><td>...</td></tr><tr><td>G120N</td><td>0.21</td><td>-18.44</td><td>0.95</td><td>&lt;0.17</td><td>...</td><td>...</td><td>0.39</td><td>-18.57</td><td>1.20</td><td>1.2</td><td>-18.46</td><td>1.24</td><td>22.7 ± 29.0</td><td>0.3 ± 0.5</td><td>2.6</td></tr><tr><td>G149N</td><td>&lt;0.16</td><td>...</td><td>...</td><td>&lt;0.19</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.6</td><td>-7.51</td><td>0.41</td><td>4.5 ± 1.3</td><td>3.5 ± 3.3</td><td>...</td></tr><tr><td>G149S</td><td>&lt;0.16</td><td>...</td><td>...</td><td>&lt;0.19</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>&lt;0.17</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G157</td><td>0.57</td><td>-7.62</td><td>0.28</td><td>&lt;0.19</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.8</td><td>-7.63</td><td>0.29</td><td>4.2 ± 0.1</td><td>16.5 ± 5.0</td><td>...</td></tr><tr><td>G174</td><td>0.55</td><td>6.27</td><td>0.33</td><td>&lt;0.16</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.7</td><td>6-7</td><td>...</td><td>...</td><td>...</td><td>0.5</td></tr><tr><td>G192N</td><td>&lt;0.16</td><td>...</td><td>...</td><td>&lt;0.17</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.6</td><td>~6</td><td>...</td><td>...</td><td>...</td><td>1.4</td></tr><tr><td>G192S</td><td>&lt;0.16</td><td>...</td><td>...</td><td>&lt;0.17</td><td>...</td><td>...</td><td>0.37</td><td>12.17</td><td>0.75</td><td>1.3</td><td>12.23</td><td>0.55</td><td>5.7 ± 0.2</td><td>6.2 ± 0.9</td><td>...</td></tr><tr><td>G204NE</td><td>0.38</td><td>1.74</td><td>0.71</td><td>&lt;0.17</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>1.6</td><td>1.57</td><td>0.47</td><td>6.0 ± 0.4</td><td>7.5 ± 1.6</td><td>...</td></tr><tr><td>G204SW</td><td>&lt;0.21</td><td>...</td><td>...</td><td>&lt;0.20</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.5</td><td>1.74</td><td>0.76</td><td>5.2 ± 3.1</td><td>1.8 ± 2.9</td><td>1.0</td></tr><tr><td>G207N1</td><td>&lt;0.22</td><td>...</td><td>...</td><td>&lt;0.22</td><td>...</td><td>...</td><td>0.44</td><td>10.48</td><td>1.20</td><td>0.9</td><td>10.71</td><td>1.10</td><td>6.1 ± 1.8</td><td>2.4 ± 1.8</td><td>...</td></tr><tr><td>G207N2</td><td>&lt;0.22</td><td>...</td><td>...</td><td>&lt;0.22</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.8</td><td>11.20</td><td>0.45</td><td>5.6 ± 1.6</td><td>3.6 ± 2.8</td><td>...</td></tr><tr><td>G207N3</td><td>&lt;0.22</td><td>...</td><td>...</td><td>&lt;0.22</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G207N4</td><td>&lt;0.22</td><td>...</td><td>...</td><td>&lt;0.22</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.4</td><td>11.28</td><td>0.54</td><td>3.5 ± 0.1</td><td>21.5 ± 12.4</td><td>0.9</td></tr><tr><td>G207N5</td><td>&lt;0.22</td><td>...</td><td>...</td><td>&lt;0.22</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.9</td><td>~11</td><td>...</td><td>...</td><td>...</td><td>0.7</td></tr><tr><td>G224S</td><td>0.22</td><td>14.44</td><td>2.59</td><td>&lt;0.19</td><td>...</td><td>...</td><td>0.49</td><td>14.4</td><td>2.17</td><td>1.5</td><td>~15</td><td>...</td><td>...</td><td>...</td><td>3.9</td></tr><tr><td>G224NE</td><td>0.15</td><td>13.87</td><td>3.46</td><td>&lt;0.19</td><td>...</td><td>...</td><td>0.36</td><td>13.75</td><td>1.46</td><td>1.6</td><td>13.95</td><td>1.46</td><td>13.6 ± 4.2</td><td>0.9 ± 0.4</td><td>...</td></tr><tr><td>G224NW</td><td>0.23</td><td>16.21</td><td>3.04</td><td>&lt;0.19</td><td>...</td><td>...</td><td>0.74</td><td>16.38</td><td>2.00</td><td>0.6</td><td>~16</td><td>...</td><td>...</td><td>...</td><td>0.2</td></tr></tbody></table>

Notes.

<sup>a</sup> The upper limit to the intensity is defined as $3\sigma$, where $\sigma$ is the rms noise level at 1 km s$^{-1}$ bin.

Three dots in $T_A^*$ means “hard to judge whether the emission is detected or not, due to low signal-to-noise ratios, baseline distortion, and/or possible spurious emission”.
<table><caption>**Table 5**
Intensities<sup>a</sup> Observed with the Receiver TZ1 toward T70 Position</caption><thead><tr><th rowspan="2">Source</th><th colspan="3">82 GHz CCS</th><th colspan="3">94 GHz CCS</th><th colspan="3">HC<sub>3</sub>N</th><th colspan="3">N<sub>2</sub>H<sup>+</sup></th><th rowspan="2">T<sub>ex</sub><br>(K)</th><th rowspan="2">τ(main)</th></tr><tr><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δν<br>(km s<sup>-1</sup>)</th><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δν<br>(km s<sup>-1</sup>)</th><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δν<br>(km s<sup>-1</sup>)</th><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δν<br>(km s<sup>-1</sup>)</th></tr></thead><tbody><tr><td>G089.9-01.9</td><td>0.53</td><td>1.32</td><td>0.32</td><td>0.44</td><td>1.44</td><td>0.47</td><td>1.23</td><td>1.29</td><td>0.45</td><td>1.1</td><td>1.49</td><td>0.60</td><td>9.0 ± 4.9</td><td>1.4 ± 1.3</td></tr><tr><td>G108N</td><td>0.16</td><td>-49.62</td><td>1.56</td><td>&lt;0.16</td><td>...</td><td>...</td><td>&lt;0.12</td><td>...</td><td>...</td><td>0.5</td><td>-49.89</td><td>1.39</td><td>...</td><td>...</td></tr><tr><td>G120N</td><td>0.21</td><td>-18.44</td><td>0.95</td><td>&lt;0.17</td><td>...</td><td>...</td><td>0.45</td><td>-18.65</td><td>0.81</td><td>1.2</td><td>-18.57</td><td>1.13</td><td>8.1 ± 1.5</td><td>1.6 ± 0.6</td></tr><tr><td>G120S</td><td>0.35</td><td>-18.42</td><td>0.73</td><td>0.33</td><td>-18.42</td><td>0.31</td><td>0.80</td><td>-18.47</td><td>0.66</td><td>&lt;0.14</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G149.5-1.2</td><td>&lt;0.16</td><td>...</td><td>...</td><td>&lt;0.19</td><td>...</td><td>...</td><td>&lt;0.14</td><td>...</td><td>...</td><td>0.6</td><td>-7.51</td><td>0.41</td><td>4.5 ± 1.3</td><td>3.5 ± 3.3</td></tr><tr><td>G157.6-12.2</td><td>0.59</td><td>-7.62</td><td>0.27</td><td>&lt;0.20</td><td>...</td><td>...</td><td>&lt;0.15</td><td>...</td><td>...</td><td>0.9</td><td>-7.61</td><td>0.29</td><td>4.5 ± 0.2</td><td>9.4 ± 1.9</td></tr><tr><td>G174.0-15.8</td><td>0.64</td><td>6.27</td><td>0.44</td><td>&lt;0.16</td><td>...</td><td>...</td><td>&lt;0.11</td><td>...</td><td>...</td><td>&lt;0.15</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G192.33-11.88</td><td>&lt;0.16</td><td>...</td><td>...</td><td>&lt;0.17</td><td>13.48</td><td>0.37</td><td>&lt;0.15</td><td>...</td><td>...</td><td>0.7</td><td>12.12</td><td>1.13</td><td>4.9 ± 0.3</td><td>2.7 ± 0.6</td></tr><tr><td>G204.4-11.3</td><td>0.38</td><td>1.74</td><td>0.71</td><td>&lt;0.20</td><td>...</td><td>...</td><td>&lt;0.18</td><td>...</td><td>...</td><td>1.4</td><td>1.59</td><td>0.47</td><td>5.6 ± 0.2</td><td>8.6 ± 1.5</td></tr><tr><td>G207N<sup>b</sup></td><td>&lt;0.22</td><td>...</td><td>...</td><td>&lt;0.24</td><td>...</td><td>...</td><td>&lt;0.19</td><td>...</td><td>...</td><td>&lt;0.23</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G224.4-0.6</td><td>&lt;0.18</td><td>...</td><td>...</td><td>&lt;0.19</td><td>...</td><td>...</td><td>&lt;0.17</td><td>...</td><td>...</td><td>1.6</td><td>13.95</td><td>1.46</td><td>13.6 ± 4.2</td><td>0.9 ± 0.4</td></tr></tbody></table>

**Notes.**

<footnote><sup>a</sup> The upper limit to the intensity is defined as $3\sigma$, where $\sigma$ is the rms noise level at 1 km s$^{-1}$ bin.</footnote>

<footnote><sup>b</sup> Incorrect position.</footnote>
<table><caption>**Table 6**
Intensities<sup>a</sup> Observed with the Receiver T70</caption><thead><tr><th rowspan="2">Source</th><th colspan="3">DNC</th><th colspan="3">HN<sup>13</sup>C</th><th colspan="3">N<sub>2</sub>D<sup>+</sup></th><th rowspan="2">T<sub>ex</sub><br>(K)</th><th rowspan="2">τ(tau)</th><th colspan="3">c-C<sub>3</sub>H<sub>2</sub></th></tr><tr><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δν<br>(km s<sup>-1</sup>)</th><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δν<br>(km s<sup>-1</sup>)</th><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δν<br>(km s<sup>-1</sup>)</th><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δν<br>(km s<sup>-1</sup>)</th></tr></thead><tbody><tr><td>G089.9-01.9</td><td>0.90</td><td>1.49</td><td>1.19</td><td>0.44</td><td>1.49</td><td>0.79</td><td>0.23</td><td>1.50</td><td>0.50</td><td>3.7 ± 0.4</td><td>2.09 ± 1.08</td><td>0.69</td><td>1.39</td><td>0.78</td></tr><tr><td>G108N</td><td>0.18</td><td>-49.46</td><td>2.48</td><td>&lt;0.089</td><td>...</td><td>2.48</td><td>&lt;0.036</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.21</td><td>-49.84</td><td>0.95</td></tr><tr><td>G120N</td><td>0.30</td><td>-18.52</td><td>1.51</td><td>0.25</td><td>-18.46</td><td>1.353</td><td>0.05 &lt; 0.036</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.51</td><td>-18.45</td><td>1.41</td></tr><tr><td>G149.5-1.2</td><td>0.17</td><td>-7.47</td><td>1.00</td><td>0.12</td><td>-7.31</td><td>0.592</td><td>0.05 &lt; 0.036</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.28</td><td>-7.44</td><td>0.46</td></tr><tr><td>G157.6-12.2</td><td>1.34</td><td>-7.66</td><td>0.90</td><td>0.53</td><td>-7.55</td><td>0.564</td><td>0.45</td><td>-7.65</td><td>0.31</td><td>4.1 ± 0.2</td><td>3.42 ± 0.66</td><td>1.25</td><td>-7.61</td><td>0.35</td></tr><tr><td>G192.33-11.88</td><td>0.81</td><td>12.14</td><td>1.06</td><td>0.22</td><td>12.32</td><td>0.959</td><td>0.28</td><td>12.16</td><td>0.59</td><td>5.8 ± 2.0</td><td>0.58 ± 0.40</td><td>0.42</td><td>12.19</td><td>0.84</td></tr><tr><td>G204.4-11.3</td><td>1.69</td><td>1.64</td><td>1.03</td><td>0.74</td><td>1.70</td><td>0.79</td><td>0.38</td><td>1.63</td><td>0.52</td><td>4.7 ± 1.4</td><td>1.68 ± 1.33</td><td>1.47</td><td>1.64</td><td>0.66</td></tr><tr><td>G207N<sup>b</sup></td><td>&lt;0.040</td><td>...</td><td>...</td><td>&lt;0.026</td><td>...</td><td>...</td><td>&lt;0.036</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.05</td><td>11.12</td><td>1.64</td></tr><tr><td>G224.4-0.6</td><td>0.23</td><td>15.76</td><td>1.42</td><td>0.17</td><td>15.73</td><td>0.479</td><td>&lt;0.044</td><td>...</td><td>...</td><td>...</td><td>...</td><td>0.19</td><td>15.69</td><td>1.35</td></tr></tbody></table>

**Notes.**

<footnote><sup>a</sup> The upper limit to the intensity is defined as $3\sigma$, where $\sigma$ is the rms noise level at 1 km s$^{-1}$ bin.</footnote>

<footnote><sup>b</sup> Incorrect position.</footnote>
<table><caption>**Table 7**
NH₃ Intensitiesª Observed with the Receiver H22 and Derived Rotation and Kinetic Temperatures</caption><thead><tr><th rowspan="2">Source</th><th colspan="3">NH₃ (1, 1)</th><th colspan="2">NH₃ (2, 2)</th><th rowspan="2">T<sub>rot</sub><br>(K)</th><th rowspan="2">T<sub>k</sub><br>(K)</th></tr><tr><th>T<sup>*</sup><sub>A</sub><br>(K)</th><th>V<sub>LSR</sub><br>(km s<sup>-1</sup>)</th><th>Δν<br>(km s<sup>-1</sup>)</th><th>T<sup>*</sup><sub>A</sub><br>(K)</th></tr></thead><tbody><tr><td>G089.9-01.9</td><td>0.87</td><td>1.59</td><td>0.86</td><td>0.11</td><td>10.5 ± 0.9</td><td>11.0 ± 1.1</td></tr><tr><td>G108N</td><td>0.49</td><td>-49.56</td><td>1.65</td><td>0.10</td><td>13.1 ± 2.8</td><td>14.3 ± 3.6</td></tr><tr><td>G108S</td><td>0.22</td><td>-49.82</td><td>2.06</td><td>&lt;0.03</td><td>&lt;16.5</td><td>&lt;19.1</td></tr><tr><td>G120N</td><td>0.42</td><td>-18.39</td><td>1.61</td><td>0.11</td><td>13.1 ± 4.1</td><td>14.3 ± 5.4</td></tr><tr><td>G120S</td><td>0.57</td><td>-18.47</td><td>1.11</td><td>0.15</td><td>11.3 ± 1.5</td><td>12.1 ± 1.9</td></tr><tr><td>G149.5-1.2</td><td>0.35</td><td>-7.49</td><td>0.96</td><td>&lt;0.03</td><td>&lt;13.4</td><td>&lt;14.8</td></tr><tr><td>G157.6-12.2</td><td>0.71</td><td>-7.68</td><td>0.72</td><td>&lt;0.03</td><td>&lt;10.7</td><td>&lt;11.4</td></tr><tr><td>G174.0-15.8</td><td>0.99</td><td>6.19</td><td>0.81</td><td>&lt;0.03</td><td>&lt;+10.5</td><td>&lt;11.1</td></tr><tr><td>G192.33-11.88</td><td>1.01</td><td>12.06</td><td>0.90</td><td>0.21</td><td>11.6 ± 1.7</td><td>12.5 ± 2.1</td></tr><tr><td>G202.00+2.65</td><td>0.80</td><td>5.08</td><td>0.77</td><td>&lt;0.06</td><td>&lt;9.8</td><td>&lt;10.2</td></tr><tr><td>G202.31-8.92</td><td>0.60</td><td>11.92</td><td>0.89</td><td>&lt;0.03</td><td>&lt;10.9</td><td>&lt;11.6</td></tr><tr><td>G204.4-11.3</td><td>1.34</td><td>1.56</td><td>0.73</td><td>0.14</td><td>9.8 ± 0.7</td><td>10.2 ± 0.8</td></tr><tr><td>G207N</td><td>0.87</td><td>11.04</td><td>1.04</td><td>0.14</td><td>12.9 ± 5.6</td><td>14.1 ± 7.3</td></tr><tr><td>G207S</td><td>0.62</td><td>11.58</td><td>1.31</td><td>&lt;0.04</td><td>11.1 ± 5.3</td><td>11.8 ± 6.5</td></tr><tr><td>G224.4-0.6</td><td>0.37</td><td>14.99</td><td>2.72</td><td>0.11</td><td>14 ± 13</td><td>15.5 ± 17.7</td></tr></tbody></table>

**Note.**

<table><caption>**Table 8**
Column Densities and Their Ratios toward SCUBA-2 Peak</caption><thead><tr><th>SCUBA-2 peak</th><th>N(CCS)<br>(cm<sup>-2</sup>)</th><th>N(N<sub>2</sub>H<sup>+</sup>)<br>(cm<sup>-2</sup>)</th><th>N(N<sub>2</sub>H<sup>+</sup>)/N(CCS)</th></tr></thead><tbody><tr><td>G089E</td><td>3.5E+12</td><td>1.2E+13</td><td>3.6</td></tr><tr><td>G089W</td><td>6.4E+12</td><td>4.5E+12</td><td>0.7</td></tr><tr><td>G108N</td><td>5.2E+12</td><td>5.4E+12</td><td>1.0</td></tr><tr><td>G108S1</td><td>6.4E+12</td><td></td><td></td></tr><tr><td>G108S2</td><td>1.1E+13</td><td>2.5E+13</td><td>2.3</td></tr><tr><td>G108S3</td><td>&lt;4.9E+12</td><td>1.7E+12 - 1.7E+13</td><td>&gt;0.3</td></tr><tr><td>G108S4</td><td>&lt;4.9E+12</td><td>1.3E+13</td><td>&gt;2.6</td></tr><tr><td>G120S1</td><td>9.8E+12</td><td>1.3E+13</td><td>1.3</td></tr><tr><td>G120S2</td><td>&lt;3.5E+12</td><td>2.1E+13</td><td>&gt;5.9</td></tr><tr><td>G120N</td><td>3.8E+12</td><td>3.5E+12</td><td>0.9</td></tr><tr><td>G149N</td><td>&lt;6.8E+12</td><td>7.2E+12</td><td>&gt;1.1</td></tr><tr><td>G149S</td><td>&lt;6.8E+12</td><td></td><td>...</td></tr><tr><td>G157</td><td>8.9E+12</td><td>2.5E+13</td><td>2.8</td></tr><tr><td>G174</td><td>5.0E+12</td><td>1.7E+12 - 1.7E+13</td><td>0.3-3.3</td></tr><tr><td>G192N</td><td>&lt;3.9E+12</td><td>4.6E+12 - 4.6E+13</td><td>&gt;1.2</td></tr><tr><td>G192S</td><td>&lt;6.9E+12</td><td>1.7E+13</td><td>&gt;2.4</td></tr><tr><td>G204NE</td><td>1.2E+13</td><td>1.7E+13</td><td>1.4</td></tr><tr><td>G204SW</td><td>...</td><td>6.7E+12</td><td></td></tr><tr><td>G207N1</td><td>&lt;3.3E+12</td><td>1.2E+13</td><td>&gt;3.8</td></tr><tr><td>G207N2</td><td>&lt;3.3E+12</td><td>7.7E+12</td><td>&gt;2.3</td></tr><tr><td>G207N3</td><td>&lt;3.3E+12</td><td></td><td>...</td></tr><tr><td>G207N4</td><td>&lt;3.3E+12</td><td>6.8E+13</td><td>&gt;21</td></tr><tr><td>G207N5</td><td>&lt;3.3E+12</td><td>2.6E+12 - 2.6E+13</td><td>&gt;0.8</td></tr><tr><td>G224S</td><td>9.6E+12</td><td>1.4E+13 - 1.4E+14</td><td>1.5-15</td></tr><tr><td>G224NE</td><td>8.6E+12</td><td>7.7E+12</td><td>0.9</td></tr><tr><td>G224NW</td><td>1.2E+13</td><td>6.4E+11 - 6.4E+12</td><td>0.05-0.5</td></tr></tbody></table>

1499. Figure 5 shows maps toward G157.6-12.2. The N₂H⁺ distribution is well correlated with the 850 µm distribution. The 82 GHz CCS emission surrounds the 850 µm (and N₂H⁺) core. The HC₃N emission shows distribution different from the N₂H⁺ distribution, and looks anticorrelated with the 82 GHz CCS emission. Nobeyama T70 observations were made toward the center of G157, a starless core. The column density ratio of N(DNC) to N(HN¹³C) is 6.9, which is larger than the value of 3.0 at L1544 (Hirota et al. 2003; Hirota & Yamamoto 2006).

### 4.6. G174.0-15.8

This clump is located in L1529 (Lynds 1962; Wouterloot & Habing 1985; Dobashi et al. 2005) in Taurus. G174.0-15.8 is a starless clump. Figure 6 shows maps toward G174.0-15.8. The N₂H⁺ distribution is more or less correlated with the 850 µm distribution. The HC₃N and 82 GHz CCS emission is distributed more extensively than the 850 µm core.

### 4.7. G192.32-11.88

G192.3-11.8 is located in the λ Orionis complex, and is associated with B30 cataloged by Barnard (1927), L1581 (Lynds 1962; Dobashi et al. 2005), and with No. 9 CO emission peak identified by Maddalena et al. (1986). It is located in the dark cloud Khavtassi 296 (Khavtassi 1960). Liu et al. (2016) discovered an extremely young Class 0 protostellar object (G192N) and a proto-brown dwarf candidate (G192S). Observations with SMA show the existence of molecular outflows associated with these objects. Figure 7 shows maps toward G192.32-11.88. The N₂H⁺ distribution shows an intensity peak toward G192S, while there is no N₂H⁺ peak corresponding to G192N. The 850 µm map of SCUBA-2 has two clear peaks, G192N being the more intense one. The HC₃N distribution is very different from that of 850 µm (and N₂H⁺), and is clumpy. G192S is associated with one HC₃N core, while there is no HC₃N counterpart to G192N. It seems that the 850 µm (and N₂H⁺) peak is surrounded by HC₃N cores.

Liu et al. (2016) detected large velocity gradient in this region in ¹³CO J = 1–0 and 2–1 in the NE–SW direction, and attributed its origin to compression by the H II region. The N₂H⁺ core inside shows an E–W velocity gradient of the order of 0.5 km s⁻¹ arcmin⁻¹ or 4 km s⁻¹ pc⁻¹. This gradient is consistent with what was observed by Liu et al. (2016) toward the center of their Clump-S in ¹³CO J = 1–0 and 2–1 (see their Figure 2). Figure 14 shows the intensity-weighted radial velocity (moment 1) map toward G192.32-11.88 in the N₂H⁺ main hyperfine emission group F₁ = 2–1 (F = 1–0, 2–1, and 3–2). This shows a velocity gradient of 0.5 km s⁻¹ across the clump in the E–W direction. Because this object is located

<footnote>ª The upper limit to the intensity is defined as 3σ, where σ is the rms noise level at 1 km s⁻¹ bin.</footnote>
<table><caption>**Table 9**
Column Densities and Their Ratios toward T70 or H22 Positions</caption><thead><tr><th>Source</th><th>N(CCS)<br>(cm<sup>-2</sup>)</th><th>N(N<sub>2</sub>H<sup>+</sup>)<br>(cm<sup>-2</sup>)</th><th>N(N<sub>2</sub>D<sup>+</sup>)<br>(cm<sup>-2</sup>)</th><th>N(HN<sup>13</sup>C)<br>(cm<sup>-2</sup>)</th><th>N(DNC)<br>(cm<sup>-2</sup>)</th><th>N(NH<sub>3</sub>)<br>(cm<sup>-2</sup>)</th><th>N(N<sub>2</sub>H<sup>+</sup>)/N(CCS)</th><th>N(DNC)/N(HN<sup>13</sup>C)</th><th>N(N<sub>2</sub>D<sup>+</sup>)/N(N<sub>2</sub>H<sup>+</sup>)</th><th>N(NH<sub>3</sub>)/N(CCS)</th></tr></thead><tbody><tr><td>G089.9-01.9</td><td>6.5E+12</td><td>4.2E+12</td><td>5.9E+12</td><td>1.5E+12</td><td>7.6E+12</td><td>5.2E+14 ± 9.5E+13</td><td>0.7</td><td>5.0</td><td>1.4</td><td>80 ± 15</td></tr><tr><td>G108N</td><td>4.8E+12</td><td>...</td><td>...</td><td>&lt;7.5E+11</td><td>1.9E+12</td><td>5.1E+14 ± 1.7E+14</td><td>...</td><td>&gt;2.5</td><td>...</td><td>106 ± 36</td></tr><tr><td>G108S</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>&lt;2.6E+14</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G120N</td><td>3.8E+12</td><td>8.9E+12</td><td>...</td><td>1.2E+12</td><td>2.0E+12</td><td>4.0E+14 ± 2.0E+14</td><td>2.4</td><td>1.7</td><td>...</td><td>106 ± 53</td></tr><tr><td>G120S</td><td>7.0E+12</td><td>...</td><td>...</td><td>...</td><td>...</td><td>5.2E+14 ± 1.4E+14</td><td>...</td><td>...</td><td>...</td><td>74 ± 19</td></tr><tr><td>G149.5-1.2</td><td>&lt;3.0E+12</td><td>7.2E+12</td><td>...</td><td>2.3E+11</td><td>7.4E+11</td><td>&lt;1.9E+14</td><td>&gt;2.4</td><td>3.2</td><td>...</td><td>...</td></tr><tr><td>G157.6-12.2</td><td>5.7E+12</td><td>1.4E+13</td><td>5.7E+12</td><td>1.3E+12</td><td>1.4E+13</td><td>&lt;2.4E+14</td><td>2.4</td><td>10.4</td><td>0.4</td><td>&lt;42</td></tr><tr><td>G174.0-15.8</td><td>1.1E+13</td><td>&lt;7.0E+12</td><td>...</td><td>...</td><td>...</td><td>&lt;1.9E+14</td><td>&lt;0.6</td><td>...</td><td>...</td><td>&lt;17</td></tr><tr><td>G192.33-11.88</td><td>&lt;4.8E+12</td><td>1.5E+13</td><td>1.6E+12</td><td>7.8E+11</td><td>4.8E+12</td><td>3.4E+14 ± 9.2E+13</td><td>&gt;3.1</td><td>6.2</td><td>0.1</td><td>&gt;71</td></tr><tr><td>G202.00+2.65</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>&lt;5.1E+14</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G202.31-8.92</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>&lt;2.6E+14</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G204.4-11.3</td><td>1.2E+13</td><td>2.0E+13</td><td>4.3E+12</td><td>3.5E+12</td><td>...</td><td>4.6E+14 ± 7.8E+13</td><td>1.6</td><td>...</td><td>0.2</td><td>37 ± 6</td></tr><tr><td>G207N<sup>a</sup></td><td>&lt;6.3E+12</td><td>...</td><td>...</td><td>...</td><td>...</td><td>2.1E+14 ± 1.5E+14</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G207S</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td><td>2.3E+14 ± 2.1E+14</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G224.4-0.6</td><td>&lt;2.7E+12</td><td>7.7E+12</td><td>...</td><td>...</td><td>...</td><td>...</td><td>&gt;2.9</td><td>...</td><td>...</td><td>...</td></tr></tbody></table>

**Note.**

<footnote><sup>a</sup> Incorrect position.</footnote>
<table><caption>**Table 10**
Fractional Abundance toward the JCMT/SCUBA-2 Peak</caption><thead><tr><th>Source</th><th>S<sub>v</sub><sup>beam a</sup><br>(mJy/beam)</th><th>N<sub>H2</sub><br>(10<sup>22</sup> cm<sup>-2</sup>)</th><th>X(CCS)</th><th>X(N<sub>2</sub>H<sup>+</sup>)</th></tr></thead><tbody><tr><td>G089E</td><td>132.2</td><td>1.7</td><td>2.0E-10</td><td>7.3E-10</td></tr><tr><td>G089W</td><td>235.7</td><td>3.0</td><td>2.1E-10</td><td>1.5E-10</td></tr><tr><td>G108N</td><td>231.9</td><td>1.8</td><td>2.9E-10</td><td>3.0E-10</td></tr><tr><td>G108S1</td><td>167.3</td><td>0.8</td><td>8.0E-10</td><td>...</td></tr><tr><td>G108S2</td><td>197.5</td><td>1.0</td><td>1.1E-09</td><td>2.5E-09</td></tr><tr><td>G108S3</td><td>175.9</td><td>0.9</td><td>...</td><td>...</td></tr><tr><td>G108S4</td><td>141.7</td><td>0.7</td><td>...</td><td>1.8E-09</td></tr><tr><td>G120S1</td><td>332.1</td><td>3.5</td><td>2.8E-10</td><td>3.6E-10</td></tr><tr><td>G120S2</td><td>116.9</td><td>1.2</td><td>...</td><td>1.7E-09</td></tr><tr><td>G120N</td><td>514.4</td><td>4.1</td><td>9.3E-11</td><td>8.7E-11</td></tr><tr><td>G149N</td><td>117.2</td><td>0.9</td><td>...</td><td>8.0E-10</td></tr><tr><td>G149S</td><td>93.2</td><td>0.7</td><td>...</td><td>...</td></tr><tr><td>G157</td><td>126.8</td><td>1.5</td><td>5.9E-10</td><td>1.7E-09</td></tr><tr><td>G174</td><td>90.3</td><td>1.1</td><td>4.5E-10</td><td>...</td></tr><tr><td>G192N</td><td>600.3</td><td>6.0</td><td>...</td><td>...</td></tr><tr><td>G192S</td><td>333.3</td><td>3.3</td><td>...</td><td>5.0E-10</td></tr><tr><td>G204NE</td><td>861.5</td><td>12.8</td><td>9.5E-11</td><td>1.3E-10</td></tr><tr><td>G204SW</td><td>338.5</td><td>5.0</td><td>...</td><td>1.3E-10</td></tr><tr><td>G207N1</td><td>386.4</td><td>3.1</td><td>...</td><td>4.0E-10</td></tr><tr><td>G207N2</td><td>216.2</td><td>1.7</td><td>...</td><td>4.5E-10</td></tr><tr><td>G207N3</td><td>185.3</td><td>1.5</td><td>...</td><td>...</td></tr><tr><td>G207N4</td><td>163.7</td><td>1.3</td><td>...</td><td>5.2E-09</td></tr><tr><td>G207N5</td><td>121.9</td><td>1.0</td><td>...</td><td>...</td></tr><tr><td>G224S</td><td>940.3</td><td>6.5</td><td>1.5E-10</td><td>...</td></tr><tr><td>G224NE</td><td>946.5</td><td>6.5</td><td>1.3E-10</td><td>1.2E-10</td></tr><tr><td>G224NW</td><td>387.5</td><td>2.7</td><td>4.4E-10</td><td>...</td></tr><tr><td>Median</td><td>206.9</td><td>1.7</td><td>2.8E-10</td><td>4.5E-10</td></tr></tbody></table>

**Note.**

in the Orion region, where the specific angular momentum was statistically investigated by Tatematsu et al. (2016), and also because this core shows a clear velocity gradient, we investigate its properties in detail. It is well known that the specific angular momentum (angular momentum per unit mass) *J/M* is roughly proportional to *R*¹.⁶ for molecular clouds and their cores having sizes of 0.1 to 30 pc in general (Goldsmith & Arquilla 1985; Goodman et al. 1993; Bodenheimer 1995). We compare the radius, velocity gradient, and the specific angular momentum among these emission lines. The beam-corrected half-intensity radius *R* is 0.26, 0.16, and 0.058 pc, the velocity

gradient is 3.9, 2.2, and 0.23 km s⁻¹; and *J/M* is 1.3 × 10²³, 4.5 × 10²², and 1.7 × 10²¹ cm² s⁻¹, respectively, in ¹³CO *J* = 1–0 and 2–1 (Liu et al. 2016) and N₂H⁺ (this study). Tatematsu et al. (2016) investigated the specific angular momentum *J/M* of N₂H⁺ cores in the Orion A GMC, and compared them with cold cloud cores observed in NH₃ by Goodman et al. (1993). Figure 15 plots the specific angular momentum *J/M* of G192.32-11.88 cores observed in this study as well as Tatematsu et al. (2016), Goodman et al. (1993). *J/M* of G192.32-11.88 in N₂H⁺ is within the range found for cores in the Orion A GMC, but is located at the high end of it. It is possible that compression by the H II region has resulted in relatively large *J/M* found in the present study.

Nobeyama T70 observations were made toward G192N associated with the Class 0 like protostar. The column density ratio of *N* (DNC) to *N* (HN¹³C) is 5.8, which is larger than the value of 3.0 at L1544 (Hirota et al. 2003; Hirota & Yamamoto 2006). Detection of DNC and N₂D⁺ indicates that this core is chemically relatively young, although the core is star-forming.

$$4.8. G202.00+2.65$$

This clump is located in the dark cloud L1613 (Lynds 1962; Dobashi et al. 2005) and Khavtassi 308 (Khavtassi 1960). *T*ₖ is derived to be <10.2 K. Figure 8 shows the continuum map. The upper limit to the kinetic temperature (10.2 K) was obtained from NH₃ observations.

$$4.9. G202.31-8.92$$

G202.31-8.92 is located in L1611 Lynds (1962), Dobashi et al. (2005) in the Orion Northern Filament, and close to No. 52 CO Emission Peak cataloged by Maddalena et al. (1986), which has two CO velocity components 8.8 and 11.4 km s⁻¹. As Maddalena et al. (1986) discussed, we assume that the distance to G202.31-8.92 is similar to that of Orion A and B GMCs. Figure 9 shows the continuum map. *T*ₖ is derived to be <11.6 K. Two velocity components (9.2 and 12.0 km s⁻¹) were detected in the ¹²CO (1–0) and ¹³CO (1–0) emission toward this source (Liu et al. 2012). The continuum emission shows a morphology similar to that of the 12.0 km s⁻¹ CO clump. The velocity of the NH₃ emission is 11.92 km s⁻¹, which is similar to that of the 12.0 km s⁻¹ CO clump.

The upper limit to the kinetic temperature (11.6 K) was obtained from NH₃ observations.

<table><caption>**Table 11**
Fractional Abundance toward the T70 Position</caption><thead><tr><th>Source</th><th>S<sub>v</sub><sup>beam a</sup><br>(mJy/beam)</th><th>N<sub>H2</sub><br>(10<sup>22</sup> cm<sup>-2</sup>)</th><th>X(CCS)</th><th>X(N<sub>2</sub>H<sup>+</sup>)</th><th>X(N<sub>2</sub>D<sup>+</sup>)</th><th>X(HN<sup>13</sup>C)</th><th>X(DNC)</th></tr></thead><tbody><tr><td>G089.9-01.9</td><td>277.7</td><td>2.0</td><td>3.3E-10</td><td>2.1E-10</td><td>2.9E-10</td><td>7.5E-11</td><td>3.8E-10</td></tr><tr><td>G108N</td><td>225.4</td><td>1.0</td><td>4.8E-10</td><td>...</td><td>...</td><td>...</td><td>1.9E-10</td></tr><tr><td>G120N</td><td>629.3</td><td>2.8</td><td>1.3E-10</td><td>3.2E-10</td><td>...</td><td>4.3E-11</td><td>7.2E-11</td></tr><tr><td>G149.5-1.2</td><td>108.2</td><td>0.4</td><td>...</td><td>...</td><td>...</td><td>5.9E-11</td><td>1.9E-10</td></tr><tr><td>G157.6-12.2</td><td>162.3</td><td>1.1</td><td>5.2E-10</td><td>1.2E-09</td><td>5.2E-10</td><td>1.2E-10</td><td>1.2E-09</td></tr><tr><td>G192.33-11.88</td><td>623.9</td><td>3.5</td><td>...</td><td>4.2E-10</td><td>4.7E-11</td><td>2.2E-11</td><td>1.4E-10</td></tr><tr><td>G204.4-11.3</td><td>1128.8</td><td>9.3</td><td>1.3E-10</td><td>2.1E-10</td><td>4.6E-11</td><td>3.8E-11</td><td>...</td></tr><tr><td>G224.4-0.6</td><td>88.4</td><td>0.3</td><td>...</td><td>...</td><td>...</td><td>...</td><td>...</td></tr><tr><td>Median</td><td>251.6</td><td>1.6</td><td>3.3E-10</td><td>3.2E-10</td><td>1.7E-10</td><td>5.1E-11</td><td>1.9E-10</td></tr></tbody></table>

**Note.**

<footnote>a Convolved with a beam of 18.8 arcsec.</footnote>

<footnote>a Convolved with a beam of 18.8 arcsec.</footnote>
<figure><img src="image_4.png" /><figcaption>**Figure 2.** Same as Figure 1 but for G108.8-00.8. (a) The 850 µm continuum (contours) levels are [0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 231.9 mJy/beam. (b) For G108N, the N<sub>2</sub>H<sup>+</sup> intensity (black contours) is calculated from a velocity range of −51.5 to −47.5 km s<sup>−1</sup> with levels of [3, 6, 9, 12, 15] × 0.088 K km s<sup>−1</sup>(1σ). For G108S, the N<sub>2</sub>H<sup>+</sup> intensity (black contours) is calculated from a velocity range of −52.5 to −48.5 km s<sup>−1</sup> with levels of [3, 6, 9, 12, 15] × 0.066 K km s<sup>−1</sup>(1σ). For G108N, the HC<sub>3</sub>N intensity (red) is calculated from a velocity range of −51.5 to −47.5 km s<sup>−1</sup> with levels of 2.5 × 0.078 K km s<sup>−1</sup>(1σ). For G108S, the HC<sub>3</sub>N intensity (red) is calculated from a velocity range of −52.5 to −48.5 km s<sup>−1</sup> with levels of [2.5, 3, 4, 5, 6] × 0.064 K km s<sup>−1</sup>(1σ). For G108N, the 82 GHz CCS intensity (blue) is calculated from a velocity range of −51.5 to −47.5 km s<sup>−1</sup> with levels of [2.5, 3, 3.5, 4, 4.5] × 0.080 K km s<sup>−1</sup>(1σ). For G108S, the 82 GHz CCS intensity (blue) is calculated from a velocity range of −52.5 to −48.5 km s<sup>−1</sup> with levels of [2.5, 3, 3.5, 4, 4.5] × 0.078 K km s<sup>−1</sup>(1σ). For G108N, the 94 GHz CCS intensity (green) is calculated from a velocity range of −51.5 to −47.5 km s<sup>−1</sup> with levels of 2.5 × 0.11 K km s<sup>−1</sup>(1σ). For G108S, the 94 GHz CCS intensity (green) is calculated from a velocity range of −52.5 to −48.5 km s<sup>−1</sup> with levels of 2.5 × 0.076 K km s<sup>−1</sup>(1σ).</figcaption></figure>

<figure><img src="image_5.png" /><figcaption>**Figure 3.** Same as Figure 1 but for G120.7+2.7. (a) The 850 µm continuum (contours) levels are [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 514.4 mJy/beam. (b) For G120N, the N<sub>2</sub>H<sup>+</sup> intensity (black contours) is calculated from a velocity range of −19.5 to −15.5 km s<sup>−1</sup> with levels of [3, 6, 9, 12, 15, 18, 21, 24, 27] × 0.098 K km s<sup>−1</sup>(1σ). For G120S, the N<sub>2</sub>H<sup>+</sup> intensity (black contours) is calculated from a velocity range of −19.5 to −16.5 km s<sup>−1</sup> with levels of [2.5, 3, 3.5, 4, 4.5, 5, 6, 7] × 0.099 K km s<sup>−1</sup>(1σ). For G120N, the HC<sub>3</sub>N intensity (red) is calculated from a velocity range of −19.5 to −15.5 km s<sup>−1</sup> with levels of [3, 4.5, 6] × 0.090 K km s<sup>−1</sup>(1σ). For G120S, the HC<sub>3</sub>N intensity (red) is calculated from a velocity range of −19.5 to −16.5 km s<sup>−1</sup> with levels of [3, 6, 9, 12] × 0.062 K km s<sup>−1</sup>(1σ). (c) For G120N, the 82 GHz CCS intensity (blue) is calculated from a velocity range of −19.5 to −15.5 km s<sup>−1</sup> with levels of [2.5, 3, 3.5, 4, 4.5] × 0.1 K km s<sup>−1</sup>(1σ). For G120S, the 82 GHz CCS intensity (blue) is calculated from a velocity range of −19.5 to −16.5 km s<sup>−1</sup> with levels of [3, 3.5, 4, 4.5, 5] × 0.080 K km s<sup>−1</sup>(1σ). For G120N, the 94 GHz CCS intensity (green) is calculated from a velocity range of −19.5 to −15.5 km s<sup>−1</sup> with levels of [2.5, 3, 3.5] × 0.11 K km s<sup>−1</sup>(1σ). For G120S, the 94 GHz CCS intensity (green) is calculated from a velocity range of −19.5 to −16.5 km s<sup>−1</sup> with levels of [3, 3.5, 4, 4.5, 5] × 0.085 K km s<sup>−1</sup>(1σ).</figcaption></figure>

### 4.10. G204.4-11.3

G204.4-11.3 is located in L1621 Lynds (1962), Dobashi et al. (2005) and the Orion B GMC, and close to No.37 CO Emission Peak cataloged by Lynds (1962), Maddalena et al. (1986), which has two CO velocity components 8.6 and 10.9 km s<sup>−1</sup>. It is located near the edge of the dark cloud Khavtassi 311 (Khavtassi 1960). As Maddalena et al. (1986) discussed, we assume that the distance to G204.4-11.3 is similar to that of Orion A and B GMCs. Figure 10 shows maps toward G204-11.3. The N<sub>2</sub>H<sup>+</sup> emission shows a peak toward the starless peak G204NE in the 850 µm continuum, but with a marginal offset of ~10′′. The HC<sub>3</sub>N is more extended than 850 µm (and N<sub>2</sub>H<sup>+</sup>). Toward G204NE (virtually identical to the T70 position), we detected the 82 GHz CCS emission (Tables 4 and 5), but the emission is too weak and narrow to draw a

reliable map. In the single pointing observations toward G204NE, we have detected both DNC and N<sub>2</sub>D<sup>+</sup>. The column density ratio of N(DNC) to N(HN<sup>13</sup>C) is 15.0, which is much larger than the value of 3.0 at L1544 (Hirota et al. 2003; Hirota & Yamamoto 2006). The high deuterium fraction ratio implies that G204NE is a starless core on the verge of star formation. Figure 16 shows the moment 1 radial velocity map toward G204-11.3 in N<sub>2</sub>H<sup>+</sup>. We do not see a prominent velocity gradient (<0.5 km s<sup>−1</sup> arcmin<sup>−1</sup> or <4 km s<sup>−1</sup> pc<sup>−1</sup>).

### 4.11. G207.3-19.8

G207.3-19.8 is located in the Orion A GMC, and close to the No. 19 CO emission peak identified by Maddalena et al. (1986). G207N is associated with the Herbig-Haro object HH58, which is a Class 0 like source. G207S is starless.
<figure><img src="image_6.png" /><figcaption>**Figure 4.** Same as Figure 1 but for G149.5-1.2. (a) The 850 µm continuum (contours) levels are [0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 117.2 mJy/beam. (b) The N₂H⁺ intensity (black contours) is calculated from a velocity range of -8.5 to -5.5 km s⁻¹ with levels of [2.5, 3, 3.5, 4, 4.5, 5, 6, 7] × 0.099 K km s⁻¹(1σ). The HC₃N intensity (red) is calculated for a velocity range of -8.5 to -5.5 km s⁻¹ with levels of [2.5, 3] × 0.080 K km s⁻¹(1σ).</figcaption></figure>

<figure><img src="image_7.png" /><figcaption>**Figure 5.** Same as Figure 1 but for G157.6-12.2. (a) The 850 µm continuum (contours) levels are [0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 126.8 mJy/beam. (b) The N₂H⁺ intensity (black contours) is calculated from a velocity range of -8.5 to -6.5 km s⁻¹ with levels of [3, 6, 9] × 0.078 K km s⁻¹(1σ). The HC₃N intensity (red) is calculated from a velocity range of -8.5 to -6.5 km s⁻¹ with levels of [2.5, 3, 3.5, 4] × 0.071 K km s⁻¹(1σ). The 82 GHz CCS intensity (blue) is calculated from a velocity range of -8.5 to -6.5 km s⁻¹ with levels of [2.5, 3, 3.5] × 0.086 K km s⁻¹(1σ).</figcaption></figure>

<figure><img src="image_8.png" /><figcaption>**Figure 6.** Same as Figure 1 but for G174.0-15.8. (a) The 850 µm continuum (contours) levels are [0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 90.3 mJy/beam. (b) Black contours represent intensity integrated for a velocity range of 5.5 to 7.5 km s⁻¹ with levels of [3, 4.5, 6] × 0.065 K km s⁻¹(1σ). The HC₃N intensity (red) is calculated from a velocity range of 5.5 to 7.5 km s⁻¹ with levels of [3, 6, 9, 12] × 0.052 K km s⁻¹(1σ). The 82 GHz CCS intensity (blue) is calculated from a velocity range of 5.5 to 7.5 km s⁻¹ with levels of [3, 4.5, 6] × 0.065 K km s⁻¹(1σ).</figcaption></figure>

Figure 11 shows maps toward G207N. The N₂H⁺ emission is well correlated with the 850 µm distribution. The N₂H⁺ emission shows a peak toward G207N1 associated with HH58. The HC₃N also shows a peak toward G207N1. Weak emission is observed also toward G207N2, G207N3, G207N4, and G207N5 in N₂H⁺, but not in HC₃N. We have not detected either the 82 GHz or 94 GHz CCS emission. In single pointing observation toward the T70 position, which was mistakenly set north of G207N, we have not detected either DNC or N₂D⁺.

Figure 12 shows the N₂H⁺ map toward G207S. The N₂H⁺ emission is more or less correlated with the 850 µm distribution, but their peak positions do not coincide completely with each other. We have not detected either the HC₃N, 82 GHz or 94 GHz CCS emission.

4.12. G224.4-0.6

This clump is located in L1658 Lynds (1962), Dobashi et al. (2005), the Orion Southern Filament (Genzel & Stutzki 1989),
<figure><img src="image_9.png" /><figcaption>**Figure 7.** Same as Figure 1 but for G192.32-11.88. (a) The 850 µm continuum (contours) levels are [0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 600 mJy/beam. (b) The N₂H⁺ intensity (black contours) is calculated from a velocity range of 11.5 to 13.5 km s⁻¹ with levels of [3, 6, 9, 12, 15, 18, 21, 24] × 0.081 K km s⁻¹(1σ). The HC₃N intensity (red) is calculated from a velocity range of 11.5 to 13.5 km s⁻¹ with levels of [3, 4, 5, 6] × 0.069 K km s⁻¹(1σ).</figcaption></figure>

<figure><img src="image_10.png" /><figcaption>**Figure 8.** The 850 µm continuum image (contours) obtained with JCMT/SCUBA-2 toward G202.00+2.65 superimposed on the WISE 22 µm image (color). Contour levels are [0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 88.8 mJy/beam.</figcaption></figure>

<caption>**Figure 9.** Same as Figure 8 but for G202.31-8.92. Contour levels are [0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 231.2 mJy/beam.</caption>

CMa R1 region (Nakano et al. 1984), and CMa OB1 (Blitz 1978; Kim et al. 1996) and near the dark cloud Khavtassi 330 (Khavtassi 1960). Figure 13 shows maps toward G224.4-0.6. The N₂H⁺ emission is well correlated with the 850 µm distribution. Both tracers have two prominent intensity peaks, i.e., G224NE and G224S. We see slight peak position offsets. The HC₃N emission is not well correlated with the 850 µm distribution, and shows a stronger peak toward the southern 850 µm source. The 82 GHz and 94 GHz CCS emissions have local emission peaks between the two 850 µm sources. T70 observations were carried out toward G224NE, and we detected DNC and HN¹³C. Figure 17 shows the moment 1 radial velocity map in N₂H⁺. We see a steep velocity gradient. The SE-NW gradient is about 0.9 km s⁻¹ arcmin⁻¹ or 3 km s⁻¹ pc⁻¹.

# 5. Discussion

## 5.1. Column Density Ratios

Hirota & Yamamoto (2006) indicated the evolutionary sequence of starless cores by using column density ratios such as N(DNC)/N(HN¹³C). It seems that N(DNC)/N(HN¹³C) in starless cores increases with core evolution (<0.66 to 3). Using their data, we can show that N(N₂H⁺)/N(CCS) is ≲0.12 for young starless cores (L1495B, L1521B, L1521E, TMC-1, and L492). According to Tatematsu et al. (2014b), N(N₂H⁺)/N(CCS) is usually ≲2-3 for starless cores, but can reach ~2-3 for evolved starless cores. Star-forming cores generally give N(N₂H⁺)/N(CCS) ≳2-3.

In the present observations, N(N₂H⁺)/N(CCS) ranges from 0.4 to 3.7, and N(DNC)/N(HN¹³C) ranges from 1.7 to 10. These results suggest that our Planck cold clumps consist of various evolutionary stages including relatively young starless cores and those on the verge of star formation. In the present observations, N(N₂D⁺)/N(N₂H⁺) ranges from 0.1 to 1.4.
<figure><img src="image_11.png" /><figcaption>**Figure 10.** Same as Figure 1 but for G204.4-11.3. (a) The 850 µm continuum (contours) levels are [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 861.5 mJy/beam. (b) The N<sub>2</sub>H<sup>+</sup> intensity (black contours) is calculated from a velocity range of 0.5 to 2.5 km s<sup>-1</sup> with levels of [3, 6, 9, 12, 15] × 0.11 K km s<sup>-1</sup>(1σ). The HC<sub>3</sub>N intensity (red) is calculated for intensity integrated for a velocity range of 0.5 to 2.5 km s<sup>-1</sup> with levels of [3, 4.5, 6, 7.5, 10] × 0.086 K km s<sup>-1</sup>(1σ).</figcaption></figure>

<figure><img src="image_12.png" /><figcaption>**Figure 11.** Same as Figure 1 but for G207N. (a) The 850 µm continuum (contours) levels are [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 386.4 mJy/beam. (b) The N<sub>2</sub>H<sup>+</sup> intensity (black contours) is calculated from a velocity range of 9.5 to 12.5 km s<sup>-1</sup> with levels of [3, 6, 9, 12, 15, 18] × 0.13 K km s<sup>-1</sup>(1σ). The HC<sub>3</sub>N intensity (red) is calculated for intensity integrated for a velocity range of 9.5 to 12.5 km s<sup>-1</sup> with levels of [3, 4.5, 6, 7.5] × 0.11 K km s<sup>-1</sup>(1σ).</figcaption></figure>

<figure><img src="image_13.png" /><figcaption>**Figure 12.** Same as Figure 1 but for G207S. (a) The 850 µm continuum (contours) levels are [0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 88.8 mJy/beam. (b) The N<sub>2</sub>H<sup>+</sup> intensity (black contours) is calculated from a velocity range of 11.5 to 12.5 km s<sup>-1</sup> with levels of [2.5, 3, 3.5, 4, 4.5, 5] × 0.083 K km s<sup>-1</sup>(1σ).</figcaption></figure>

Fontani et al. (2006) and Chen et al. (2011) studied the column density ratio of N<sub>2</sub>D<sup>+</sup> to N<sub>2</sub>H<sup>+</sup> (they call this the deuterium fractionation D<sub>frac</sub>) toward massive protostellar cores, and compared it with those of low-mass prestellar cores by Crapsi et al. (2005). N(N<sub>2</sub>D<sup>+</sup>)/N(N<sub>2</sub>H<sup>+</sup>) is of order 10<sup>-1</sup> in low-mass prestellar cores (Crapsi et al. 2005), and of order 10<sup>-2</sup> in massive protostellar IRAS cores (Fontani et al. 2006). The ratio is estimated to be 0.35 and 0.08 at typical cold clouds, L134N

and TMC-1N, respectively (Tiné et al. 2000). Our N<sub>2</sub>D<sup>+</sup> detected cores have larger N(N<sub>2</sub>D<sup>+</sup>)/N(N<sub>2</sub>H<sup>+</sup>) values than the massive protostellar IRAS cores of Fontani et al. (2006).

In G149.5-1.2 (contains a *WISE* source), G192N (contains a Class 0), G207N (contains HH58), and G207S, we did not detect the 82 GHz CCS emission over the OTF map regions. The H<sub>2</sub> column density of our sources are 3 × 10<sup>21</sup> cm<sup>-2</sup> or higher (Tables 10 and 11). In G149.5-1.2, the H<sub>2</sub> column
<figure><img src="image_14.png" /><figcaption>**Figure 13.** Same as Figure 1 but for G224.4-0.6. (a) The 850 µm continuum (contours) levels are [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9] × 946.5 mJy/beam. (b) The $N_2H^+$ intensity (black contours) is calculated from a velocity range of 12.5 to 17.5 km s$^{-1}$ with levels of [3, 5, 10, 15, 20, 25, 30] × 0.15 K km s$^{-1}$(1σ). The $HC_3N$ intensity (red) is calculated from a velocity range of 12.5 to 17.5 km s$^{-1}$ with levels of [3, 6, 9, 12] × 0.12 K km s$^{-1}$(1σ). (c) The 82 GHz CCS intensity (blue) is calculated for a velocity range of 12.5 to 17.5 km s$^{-1}$ with levels of [3, 4.5, 6, 7.5] × 0.13 K km s$^{-1}$. The 94 GHz CCS intensity (green) is calculated from a velocity range of 12.5 to 17.5 km s$^{-1}$ with levels of [3, 4.5, 6] × 0.14 K km s$^{-1}$(1σ).</figcaption></figure>

<figure><img src="image_15.png" /><figcaption>**Figure 14.** The intensity-weighted radial velocity (moment 1) map (color) toward G192.32-11.88 in the $N_2H^+$ $J = 1-0$ $F_1 = 2-1$ main hyperfine emission group $F_1 = 2-1$ ($F = 1-0$, 2-1, and 3-2) overlaid on the integrated intensity (moment 0) contour map. The emission less than $2\sigma$ is ignored in the moment 1 calculation. The contour levels are the same as those in Figure 7.</figcaption></figure>

density is lower than $1 \times 10^{22} \text{ cm}^{-2}$. It is possible that a low column density is the reason for non-detection of CCS. The $H_2$ column density toward G192N (contains Class 0) is as high as $6 \times 10^{22} \text{ cm}^{-2}$, so non-detection of CCS probably means that the gas is chemically evolved. In G108S, the $H_2$ column density is as low as $\sim 1 \times 10^{22} \text{ cm}^{-2}$, but we detected the 82 GHz CCS emission. G089W (starless) should be chemically young, because $N(^{12}\text{C})/N(\text{CCS})$ is as small as 0.7 and $N(^{12}\text{N})/N(^{12}\text{N}_2H^+)$ is as high as 1.4. G157.6-12.2 (starless) is young, because $N(\text{DNC})/N(\text{HN}^{13}\text{C})$ is as high as 10.4. G108N (starless) and G204NE (starless) show $N(^{12}\text{N}_2H^+)/N(\text{CCS})$ is $\sim 2$, which is close to the border between starless and star-forming cores in Tatematsu et al. (2014b).

In the next subsection, we discuss the evolutionary stage of our Planck cold clumps on the basis of the column density ratios in Tables 8 and 9. We assume the filling factor is unity when we estimate the column density, but it is possible that the beam filling factor is less than unity. If beam filling factors are similar between molecules, then the column density ratio will be less affected by unknown absolute values of the filling factor. Because $T_k$ is $\lesssim 25$ K in general, we can use $N(^{12}\text{N}_2H^+)/N(\text{CCS})$ as a chemical evolution tracer (Tatematsu et al. 2014b).

<figure><img src="image_16.png" /><figcaption>**Figure 15.** $J/M-R$ diagram for G192.32-11.88 in $N_2H^+$ in this study (box with cross), Orion A GMC cores (open circles, Tatematsu et al. 2016), and cold dark cloud cores (filled circles, Goodman et al. 1993). The thin solid straight line is computed using a linear least-squares program for cold dark cloud cores.</figcaption></figure>

The beam sizes for CCS and $NH_3$ differ by a factor of four, and $N(NH_3)/N(\text{CCS})$ suffers from sampling/averaging over very different size scales. We thus consider $N(NH_3)/N(\text{CCS})$ much less reliable.

## 5.2. Chemical Evolution Factor

We introduce a new parameter to represent the chemical evolution by using molecular column density ratios, the chemical evolution factor (CEF). We define CEF so that starless cores have CEFs of $\sim -100$ to 0, and star-forming cores show $\sim 0$ to 100. Starless cores having CEF $\sim 0$ are regarded as being on the verge of star formation. We use the form of CEF = $\log([N(A)/N(B)]/[N_0(A)/N_0(B)])^*d$ for the column density ratio of molecule A to molecule B. $N_0(A)/N_0(B)$ is chosen to be the column density ratio at the time of star formation. For $(N(^{12}\text{N}_2H^+)/N(\text{CCS}))$ and $(N(NH_3)/N(\text{CCS}))$,
<figure><img src="image_17.png" /><figcaption>**Figure 16.** The radial velocity (moment 1) map (color) toward G204.4-11.3 in N₂H⁺ superimposed on the integrated intensity (moment 0) map. The contour levels are the same as those in Figure 12.</figcaption></figure>

<figure><img src="image_18.png" /><figcaption>**Figure 17.** The radial velocity (moment 1) map (color) toward G224.4-0.6 in N₂H⁺ superimposed on the integrated intensity (moment 0) map. The contour levels are the same as those in Figure 16.</figcaption></figure>

$N_0(A)/N_0(B)$ corresponds to the border between starless and star-forming cores. For $N(DNC)/N(HN^{13}C)$ and $N(N_2D^+)/N(N_2H^+)$, $N_0(A)/N_0(B)$ is the highest value observed for starless cores. The factor $d$ is determined so that all starless cores range approximately from -100 to 0. By taking into account the observational results of Suzuki et al. (1992), Crapsi et al. (2005), Hirota & Yamamoto (2006), Tatematsu et al. (2014b), we define CEF as $CEF = \log(N(N_2H^+)/N(CCS))/2.5)^*50$, $\log(N(DNC)/N(HN^{13}C)/3)^*120$, $\log(N(N_2D^+)/N(N_2H^+)/0.3)^*50$, and $\log(N(NH_3)/N(CCS)/70)^*70$, for starless cores with $T_k \sim 10-20$ K at a spatial resolution of order 0.015-0.05 pc (for 0.1 pc sized structure "molecular cloud core"). These expressions should be only valid for the above-mentioned temperature range and spatial resolution, because we determined the CEF by using data obtained for molecular clumps or molecular cloud cores having such temperatures and observed at such spatial resolutions. The chemical reaction will depend on density, temperature, radiation strength, cosmic-ray strength, etc. The deuterium fraction will be lower for warm cores (Snell & Wootten 1979; Wootten 1987; Schilke et al. 1992; Tatematsu et al. 2010). It seems that the deuterium fraction decreases after the onset of star formation

<figure><img src="image_19.png" /><figcaption>**Figure 18.** CEF for starless sources in the literature.</figcaption></figure>

<table><caption>**Table 12**
CEF Based on the $N(N_2H^+)/N(CCS)$ Column Density Ratio toward the Starless SCUBA-2 Peak</caption><thead><tr><td>SCUBA-2 peak</td><td>CEF(N<sub>2</sub>H<sup>+</sup>, CCS)</td></tr></thead><tbody><tr><td>G089E</td><td>(8)</td></tr><tr><td>G089W</td><td>(-27)</td></tr><tr><td>G108N</td><td>(-19)</td></tr><tr><td>G108S2</td><td>(-2)</td></tr><tr><td>G120S2</td><td>(>19)</td></tr><tr><td>G120N</td><td>(-21)</td></tr><tr><td>G157</td><td>3</td></tr><tr><td>G174</td><td>-44-6</td></tr><tr><td>G204NE</td><td>-13</td></tr><tr><td>G207N2</td><td>>-2</td></tr><tr><td>G207N4</td><td>>46</td></tr><tr><td>G207N5</td><td>>-25</td></tr><tr><td>G224NW</td><td>(-83--33)</td></tr></tbody></table>

(Emprechtinger et al. 2009; Sakai et al. 2012; Fontani et al. 2014; Sakai et al. 2015). Because the nature of this decrease has not yet been fully characterized observationally, we do not use star-forming cores for CEF based on the deuterium fractionation. Figure 18 shows the resulting CEF using the data in the literature (Crapsi et al. 2005; Hirota & Yamamoto 2006; Hirota et al. 2009).

Tables 12 and 13 and Figures 19 and 20 show the CEFs estimated in the present study. We regard cores as star-forming if the first entry of comments in Table 3 suggests a possibility of star formation (e.g., Class 0, Class I etc.). Our beam size with receivers TZ1 and T70 corresponds to 0.1 and 0.3 pc at a distance of 700 pc and 3.5 kpc, respectively. To see the effect of very different spatial resolution (and probably very different volume density and very different beam-filling factor), we show sources located beyond 1 kpc in parentheses. In this paper, we treat only starless cores for CEF, because evolution of star-forming cores has not been well characterized yet. If we mistakenly identified star-forming cores as starless, we may mistakenly obtain lower CEF due to decrease in the deuterium fractionation after star formation. If this is the case, we may see
<table><caption>**Table 13**
CEF toward the Starless T70 Position</caption><thead><tr><th>Source</th><th>CEF(N<sub>2</sub>H<sup>+</sup>, CCS)</th><th>CEF(DNC, HN<sup>13</sup>C)</th><th>CEF(N<sub>2</sub>D<sup>+</sup>, N<sub>2</sub>H<sup>+</sup>)</th><th>CEF(average)</th></tr></thead><tbody><tr><td>G089.9-01.9</td><td>(-29)</td><td>(27)</td><td>(33)</td><td>(10 ± 34)</td></tr><tr><td>G108N</td><td>...</td><td>(-9)</td><td>...</td><td>(-9)</td></tr><tr><td>G120N</td><td>(-1)</td><td>(-30)</td><td>...</td><td>(-16 ± 20)</td></tr><tr><td>G157.6-12.2</td><td>-1</td><td>65</td><td>7</td><td>24 ± 36</td></tr><tr><td>G174.0-15.8</td><td>&lt;-30</td><td>...</td><td>...</td><td>...</td></tr><tr><td>G204.4-11.3</td><td>-10</td><td>...</td><td>-7</td><td>-8 ± 2</td></tr><tr><td>G224.4-0.6</td><td>(&gt;3)</td><td>...</td><td>...</td><td>...</td></tr></tbody></table>

<figure><img src="image_20.png" /><figcaption>**Figure 19.** CEF for starless SCUBA-2 peaks based on the column density ratio of $N(N_2H^+)/N(CCS)$. The source name in parentheses means distance is larger than 1 kpc. The range reflects the uncertainty for the $N_2H^+$ optical depth for cores for which hyperfine fitting was not successful.</figcaption></figure>

<figure><img src="image_21.png" /><figcaption>**Figure 20.** CEF at starless T70 positions based on multiple column density ratios. The source name in parentheses means distance is larger than 1 kpc. The range reflects the upper and lower limit to $N(N_2H^+)/N(CCS)$.</figcaption></figure>

inconsistency between CEF based on the deuterium fractionation and that based on $N(N_2H^+)/N(CCS)$. CEF(average) does not include the upper or lower limit to $N(N_2H^+)/N(CCS)$. For

$N_2H^+$) is a lower limit, but because this is a starless core, we will not provide a positive CEF(DNC, $HN^{13}C$) value. That means $CEF(DNC, HN^{13}C) = -9$ to 0 nominally. However, this does not mean the estimate is very accurate. Then, we simply adopt this lower limit value of -9 to avoid being misleading. Figures 19 and 20 show that G174.0-15.8 is chemically young, and G204NE seems to be in the intermediate stage (on the verge of star formation).

The advantage of Planck cold clumps is that they are cold ($\lesssim 20$ K), and less affected by temperature effects. We have detected the $N_2H^+$ (1-0) emission from all the 13 clumps mapped with the Nobeyama 45 m telescope and receiver TZ1. The optically thin critical density for this transition is $6.1 \times 10^4$ and $4.1 \times 10^4$ cm$^{-3}$ for 10 and 20 K, respectively (Shirley 2015). The volume density $n$ for dense cores in cold molecular clouds detected in $N_2H^+$ (1-0) is $\gtrsim 3 \times 10^4$ cm$^{-3}$ (Caselli et al. 2002). Thus, we can assume that the 13 mapped Planck cold clumps have densities higher than $\gtrsim 3 \times 10^4$ cm$^{-3}$. With increasing density, the chemical reaction timescale will decrease. Then, the change in CEF will correspond to longer timescales for lower densities. The physical nature of the Planck cold clumps such as radius, mass, and volume density will be discussed in detail in a separate paper.

### 5.3. Molecular Distribution

Next, we investigate the morphology. In G089.9-01.9, the 82 GHz and 94 GHz CCS emission (young molecular gas) is distributed as if it surrounds the $N_2H^+$ core (evolved gas). In G157.6-12.2, the 82 GHz CCS emission is distributed as if it surrounds the $N_2H^+$ core. Such configurations were previously reported in Aikawa et al. (2001) for L1544, and also starless NH$_3$ core surrounded by CCS configurations are also observed by Lai & Crutcher (2000) for L1498 and Tatematsu et al. (2014a) for Orion A GMC. L1544 shows evidence of the prestellar collapse. Therefore, these cores could be good targets for further studies for the initial conditions of star formation. For G157.6-12.2, CEF is $\gtrsim 0$, and its linewidth is as narrow as 0.3 km s$^{-1}$. It is possible that this core is a coherent core that has largely dissipated turbulence, and is on the verge of star formation (Tatematsu et al. 2014a; Ohashi et al. 2016b). In G120S1, G120S2, and G224.4-0.6 $N_2H^+$ and CCS distribution are largely different. G089.9-01.9, G120S, G157.6-12.2 are cold (<11K), which may suggest depletion of CCS (cf., Aikawa et al. (2001), Bergin et al. (2002), Caselli et al. (2002). On the other hand, $N_2H^+$ peaks are detected in the HC$_3$N emission in these cores. In G149N, the HC$_3$N emission (young molecular gas) is distributed on the both sides of the $N_2H^+$ core (evolved gas), which is also interesting. In G108N and G108S, the 82 GHz CCS and $N_2H^+$ emission coexist roughly, but,
again, this could be due to poorer physical resolution or a
projection effect.

## 6. Summary

Thirteen Planck cold clumps were observed with the James
Clerk Maxwell Telescope/SCUBA-2 and with the Nobeyama
45 m radio telescope. The N₂H⁺ spatial distribution is similar
to SCUBA-2 dust distribution. The spatial distribution of
HC₃N, 82 GHz CCS, and 94 GHz CCS emission is often
different from that of the N₂H⁺ emission. The CCS emission is
often very clumpy. In G089.9-01.9 and G157.6-12.2, the CCS
emission surrounds the N₂H⁺ core, which resembles the case of
L1544 and suggests that they are on the verge of star formation.
The detection rate of N₂D⁺ is 50%. We investigated chemical
evolutionary stages of starless Planck cold clumps using the
newly defined CEF. We found that G174.0-15.8 is chemically
young, and G089E, G157.6-12.2, and G204NE seem in the
intermediate stage (on the verge of star formation). In addition,
we observed NH₃, and determined the kinetic temperature Tₗ.

M.K. was supported by the Basic Science Research Program
through the National Research Foundation of Korea (NRF)
funded by the Ministry of Science, ICT & Future Planning
(No. NRF-2015R1C1A1A01052160). M.J. acknowledges the
support of the Academy of Finland Grant No. 285769.
K.W. was supported by grant WA3628-1/1 of the German
Research Foundation (DFG) through the priority program 1573
("Physics of the Interstellar Medium").

We wish to thank the anonymous referee for the helpful comments. The James Clerk Maxwell Telescope is operated by the East Asian Observatory on behalf of The National Astronomical Observatory of Japan, Academia Sinica Institute of Astronomy and Astrophysics, the Korea Astronomy and Space Science Institute, the National Astronomical Observatories of China and the Chinese Academy of Sciences (Grant No. XDB09000000), with additional funding support from the Science and Technology Facilities Council of the United Kingdom and participating universities in the United Kingdom and Canada. The data analysis was carried out on the open-use data analysis computer system at the Astronomy Data Center, ADC, of the National Astronomical Observatory of Japan.

Facilities: JCMT, No:45m.

Software: AIPS, NewStar, NOSTAR.

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