Artículo de revista
Astrochemical Properties of Planck Cold Clumps
Fecha
2017Registro en:
Astrophysical Journal, Supplement Series, 228:12 (20pp), 2017 February
00670049
10.3847/1538-4365/228/2/12
Autor
Tatematsu, Ken'Ichi
Liu, Tie
Ohashi, Satoshi
Sanhueza, Patricio
Nguyen Lu'O'Ng, Quang
Hirota, Tomoya
Liu, Sheng Yuan
Hirano, Naomi
Choi, Minho
Kang, Miju
Thompson, Mark A.
Fuller, Gary
Wu, Yuefang
Li, Di
Di Francesco, James
Kim, Kee Tae
Wang, Ke
Ristorcelli, Isabelle
Juvela, Mika
Shinnaga, Hiroko
Cunningham, María
Saito, Masao
Lee, Jeong-Eun
Tóth, L. Viktor
He, Jinhua
Sakai, Takeshi
Kim, Jungha
Institución
Resumen
We observed 13 Planck cold clumps with the James Clerk Maxwell Telescope/SCUBA-2 and with the Nobeyama 45 m radio telescope. The N2H+ distribution obtained with the Nobeyama telescope is quite similar to SCUBA-2 dust distribution. The 82 GHz HC3N, 82 GHz CCS, and 94 GHz CCS emission are often distributed differently with respect to the N2H+ 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, (HNC)-C-13, N2D+, and cyclic-C3H2 toward nine clumps. The detection rate of N2D+ is 50%. Furthermore, we observed the NH3 emission toward 15 Planck cold clumps to estimate the kinetic temperature, and confirmed that most targets are cold (less than or similar to 20 K). In two of the starless clumps we observed, the CCS emission is distributed as it surrounds the N2H+ core (chemically evolved gas), which resembles the case of L1544, a prestellar core showing collapse. In addition, we detected both DNC and N2D+. 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.