TY - JOUR
T1 - Astrochemical Properties of Planck Cold Clumps
AU - Tatematsu, Ken'ichi
AU - Liu, Tie
AU - Ohashi, Satoshi
AU - Sanhueza, Patricio
AU - Nguyen-Luong, Quang
AU - Hirota, Tomoya
AU - Liu, Sheng-Yuan
AU - Hirano, Naomi
AU - Choi, Minho
AU - Kang, Miju
AU - Thompson, Mark
AU - Fuller, Garry
AU - Wu, Yuefang
AU - Francesco, James Di
AU - Kim, Kee-Tae
AU - Wang, Ke
AU - Ristorcelli, Isabelle
AU - Juvela, Mika
AU - Shinnaga, Hiroko
AU - Cunningham, Maria R.
AU - Saito, Masao
AU - Lee, Jeong-Eun
AU - Toth, L. Viktor
AU - He, Jinhua
AU - Sakai, Takeshi
AU - Kim, Jungha
AU - collaboration, JCMT Large Program "SCOPE"
AU - collaboration, TRAO Key Science Program "TOP"
N1 - Ken’ichi Tatematsu, et al, 'Astrochemical Properties of Planck Cold Clumps', The Astrophysical Journal Supplement Series, Vol. 228 (2), 20 pp, February 2017, doi:10.3847/1538-4365/228/2/12.
© 2017. The American Astronomical Society. All rights reserved.
PY - 2017/3/1
Y1 - 2017/3/1
N2 - We observed thirteen Planck cold clumps with the James Clerk Maxwell Telescope/SCUBA-2 and with the Nobeyama 45 m radio telescope. The N$_2$H$^+$ distribution obtained with the Nobeyama telescope is quite similar to SCUBA-2 dust distribution. The 82 GHz HC$_3$N, 82 GHz CCS, and 94 GHz CCS emission are often distributed differently with respect to the N$_2$H$^+$ 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$^{13}$C, N$_2$D$^+$, cyclic-C$_3$H$_2$ toward nine clumps. The detection rate of N$_2$D$^+$ is 50\%. Furthermore, we observed the NH$_3$ emission toward 15 Planck cold clumps to estimate the kinetic temperature, and confirmed that most of targets are cold ($\lesssim$ 20 K). In two of the starless clumps observe, the CCS emission is distributed as it surrounds the N$_2$H$^+$ core (chemically evolved gas), which resembles the case of L1544, a prestellar core showing collapse. In addition, we detected both DNC and N$_2$D$^+$. 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.
AB - We observed thirteen Planck cold clumps with the James Clerk Maxwell Telescope/SCUBA-2 and with the Nobeyama 45 m radio telescope. The N$_2$H$^+$ distribution obtained with the Nobeyama telescope is quite similar to SCUBA-2 dust distribution. The 82 GHz HC$_3$N, 82 GHz CCS, and 94 GHz CCS emission are often distributed differently with respect to the N$_2$H$^+$ 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$^{13}$C, N$_2$D$^+$, cyclic-C$_3$H$_2$ toward nine clumps. The detection rate of N$_2$D$^+$ is 50\%. Furthermore, we observed the NH$_3$ emission toward 15 Planck cold clumps to estimate the kinetic temperature, and confirmed that most of targets are cold ($\lesssim$ 20 K). In two of the starless clumps observe, the CCS emission is distributed as it surrounds the N$_2$H$^+$ core (chemically evolved gas), which resembles the case of L1544, a prestellar core showing collapse. In addition, we detected both DNC and N$_2$D$^+$. 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.
KW - astro-ph.GA
U2 - 10.3847/1538-4365/228/2/12
DO - 10.3847/1538-4365/228/2/12
M3 - Article
SN - 0067-0049
VL - 228
JO - Astrophysical Journal, Supplement Series
JF - Astrophysical Journal, Supplement Series
IS - 2
ER -