Astrochemical Properties of Planck Cold Clumps
- National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
- Korea Astronomy and Space Science Institute, Daedeokdaero 776, Yuseong, Daejeon 305-348 (Korea, Republic of)
- Department of Astronomy, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)
- Academia Sinica Institute of Astronomy and Astrophysics, 11F of Astronomy-Mathematics Building, AS/NTU. No.1, Section 4, Roosevelt Rd, Taipei 10617, Taiwan (China)
- Centre for Astrophysics Research, Science and Technology Research Institute, University of Hertfordshire, Hatfield, AL10 9AB (United Kingdom)
- Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom)
- Department of Astronomy, Peking University, 100871, Beijing (China)
- National Astronomical Observatories, Chinese Academy of Sciences, Beijing, 100012 (China)
- NRC Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada)
- European Southern Observatory (Germany)
- IRAP, CNRS (UMR5277), Universite Paul Sabatier, 9 avenue du Colonel Roche, BP 44346, F-31028, Toulouse Cedex 4 (France)
- Department of physics, University of Helsinki, FI-00014, Helsinki (Finland)
- Department of Physics, Kagoshima University, 1-21-35, Korimoto, Kagoshima, 890-0065 (Japan)
We observed 13 Planck cold clumps with the James Clerk Maxwell Telescope/SCUBA-2 and with the Nobeyama 45 m radio telescope. The N{sub 2}H{sup +} distribution obtained with the Nobeyama telescope is quite similar to SCUBA-2 dust distribution. The 82 GHz HC{sub 3}N, 82 GHz CCS, and 94 GHz CCS emission are often distributed differently with respect to the N{sub 2}H{sup +} 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}C, N{sub 2}D{sup +}, and cyclic-C{sub 3}H{sub 2} toward nine clumps. The detection rate of N{sub 2}D{sup +} is 50%. Furthermore, we observed the NH{sub 3} 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{sub 2}H{sup +} core (chemically evolved gas), which resembles the case of L1544, a prestellar core showing collapse. In addition, we detected both DNC and N{sub 2}D{sup +}. 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.
- OSTI ID:
- 22661326
- Journal Information:
- Astrophysical Journal, Supplement Series, Vol. 228, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0067-0049
- Country of Publication:
- United States
- Language:
- English
Similar Records
GAS EMISSIONS IN PLANCK COLD DUST CLUMPS-A SURVEY OF THE J = 1-0 TRANSITIONS OF {sup 12}CO, {sup 13}CO, AND C{sup 18}O
ALMA observations of the IRDC clump G34.43+00.24 MM3: DNC/HNC ratio