The Properties of Planck Galactic Cold Clumps in the L1495 Dark Cloud

Mengyao Tang, Tie Liu, Sheng Li Qin, Kee Tae Kim, Yuefang Wu, Ken'Ichi Tatematsu, Jinghua Yuan, Ke Wang, Harriet Parsons, Patrick M. Koch, Patricio Sanhueza, D. Ward-Thompson, L. Tóth, Archana Soam, Chang Won Lee, David Eden, James Di Francesco, Jonathan Rawlings, Mark G. Rawlings, Julien MontillaudChuan Peng Zhang, M. R. Cunningham

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Planck Galactic Cold Clumps (PGCCs) possibly represent the early stages of star formation. To understand better the properties of PGCCs, we studied 16 PGCCs in the L1495 cloud with molecular lines and continuum data from Herschel, JCMT/SCUBA-2, and the PMO 13.7 m telescope. Thirty dense cores were identified in 16 PGCCs from 2D Gaussian fitting. The dense cores have dust temperatures of T d = 11-14 K, and H2 column densities of = (0.36-2.5) × 1022 cm-2. We found that not all PGCCs contain prestellar objects. In general, the dense cores in PGCCs are usually at their earliest evolutionary stages. All the dense cores have non-thermal velocity dispersions larger than the thermal velocity dispersions from molecular line data, suggesting that the dense cores may be turbulence-dominated. We have calculated the virial parameter α and found that 14 of the dense cores have α <2, while 16 of the dense cores have α >2. This suggests that some of the dense cores are not bound in the absence of external pressure and magnetic fields. The column density profiles of dense cores were fitted. The sizes of the flat regions and core radii decrease with the evolution of dense cores. CO depletion was found to occur in all the dense cores, but is more significant in prestellar core candidates than in protostellar or starless cores. The protostellar cores inside the PGCCs are still at a very early evolutionary stage, sharing similar physical and chemical properties with the prestellar core candidates.

Original languageEnglish
Article number141
JournalAstrophysical Journal
Volume856
Issue number2
DOIs
Publication statusPublished - Apr 1 2018

Fingerprint

clumps
pressure field
cold
chemical property
physical property
turbulence
dust
magnetic field
pressure distribution
chemical properties
star formation
depletion
temperature

Keywords

  • ISM: clouds
  • ISM: individual objects (L1495)
  • ISM: molecules
  • stars: formation

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Tang, M., Liu, T., Qin, S. L., Kim, K. T., Wu, Y., Tatematsu, KI., ... Cunningham, M. R. (2018). The Properties of Planck Galactic Cold Clumps in the L1495 Dark Cloud. Astrophysical Journal, 856(2), [141]. https://doi.org/10.3847/1538-4357/aaadad

The Properties of Planck Galactic Cold Clumps in the L1495 Dark Cloud. / Tang, Mengyao; Liu, Tie; Qin, Sheng Li; Kim, Kee Tae; Wu, Yuefang; Tatematsu, Ken'Ichi; Yuan, Jinghua; Wang, Ke; Parsons, Harriet; Koch, Patrick M.; Sanhueza, Patricio; Ward-Thompson, D.; Tóth, L.; Soam, Archana; Won Lee, Chang; Eden, David; Francesco, James Di; Rawlings, Jonathan; Rawlings, Mark G.; Montillaud, Julien; Zhang, Chuan Peng; Cunningham, M. R.

In: Astrophysical Journal, Vol. 856, No. 2, 141, 01.04.2018.

Research output: Contribution to journalArticle

Tang, M, Liu, T, Qin, SL, Kim, KT, Wu, Y, Tatematsu, KI, Yuan, J, Wang, K, Parsons, H, Koch, PM, Sanhueza, P, Ward-Thompson, D, Tóth, L, Soam, A, Won Lee, C, Eden, D, Francesco, JD, Rawlings, J, Rawlings, MG, Montillaud, J, Zhang, CP & Cunningham, MR 2018, 'The Properties of Planck Galactic Cold Clumps in the L1495 Dark Cloud', Astrophysical Journal, vol. 856, no. 2, 141. https://doi.org/10.3847/1538-4357/aaadad
Tang, Mengyao ; Liu, Tie ; Qin, Sheng Li ; Kim, Kee Tae ; Wu, Yuefang ; Tatematsu, Ken'Ichi ; Yuan, Jinghua ; Wang, Ke ; Parsons, Harriet ; Koch, Patrick M. ; Sanhueza, Patricio ; Ward-Thompson, D. ; Tóth, L. ; Soam, Archana ; Won Lee, Chang ; Eden, David ; Francesco, James Di ; Rawlings, Jonathan ; Rawlings, Mark G. ; Montillaud, Julien ; Zhang, Chuan Peng ; Cunningham, M. R. / The Properties of Planck Galactic Cold Clumps in the L1495 Dark Cloud. In: Astrophysical Journal. 2018 ; Vol. 856, No. 2.
@article{4ebcacadff2f4e458e3c92bda62bf687,
title = "The Properties of Planck Galactic Cold Clumps in the L1495 Dark Cloud",
abstract = "Planck Galactic Cold Clumps (PGCCs) possibly represent the early stages of star formation. To understand better the properties of PGCCs, we studied 16 PGCCs in the L1495 cloud with molecular lines and continuum data from Herschel, JCMT/SCUBA-2, and the PMO 13.7 m telescope. Thirty dense cores were identified in 16 PGCCs from 2D Gaussian fitting. The dense cores have dust temperatures of T d = 11-14 K, and H2 column densities of = (0.36-2.5) × 1022 cm-2. We found that not all PGCCs contain prestellar objects. In general, the dense cores in PGCCs are usually at their earliest evolutionary stages. All the dense cores have non-thermal velocity dispersions larger than the thermal velocity dispersions from molecular line data, suggesting that the dense cores may be turbulence-dominated. We have calculated the virial parameter α and found that 14 of the dense cores have α <2, while 16 of the dense cores have α >2. This suggests that some of the dense cores are not bound in the absence of external pressure and magnetic fields. The column density profiles of dense cores were fitted. The sizes of the flat regions and core radii decrease with the evolution of dense cores. CO depletion was found to occur in all the dense cores, but is more significant in prestellar core candidates than in protostellar or starless cores. The protostellar cores inside the PGCCs are still at a very early evolutionary stage, sharing similar physical and chemical properties with the prestellar core candidates.",
keywords = "ISM: clouds, ISM: individual objects (L1495), ISM: molecules, stars: formation",
author = "Mengyao Tang and Tie Liu and Qin, {Sheng Li} and Kim, {Kee Tae} and Yuefang Wu and Ken'Ichi Tatematsu and Jinghua Yuan and Ke Wang and Harriet Parsons and Koch, {Patrick M.} and Patricio Sanhueza and D. Ward-Thompson and L. T{\'o}th and Archana Soam and {Won Lee}, Chang and David Eden and Francesco, {James Di} and Jonathan Rawlings and Rawlings, {Mark G.} and Julien Montillaud and Zhang, {Chuan Peng} and Cunningham, {M. R.}",
year = "2018",
month = "4",
day = "1",
doi = "10.3847/1538-4357/aaadad",
language = "English",
volume = "856",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "2",

}

TY - JOUR

T1 - The Properties of Planck Galactic Cold Clumps in the L1495 Dark Cloud

AU - Tang, Mengyao

AU - Liu, Tie

AU - Qin, Sheng Li

AU - Kim, Kee Tae

AU - Wu, Yuefang

AU - Tatematsu, Ken'Ichi

AU - Yuan, Jinghua

AU - Wang, Ke

AU - Parsons, Harriet

AU - Koch, Patrick M.

AU - Sanhueza, Patricio

AU - Ward-Thompson, D.

AU - Tóth, L.

AU - Soam, Archana

AU - Won Lee, Chang

AU - Eden, David

AU - Francesco, James Di

AU - Rawlings, Jonathan

AU - Rawlings, Mark G.

AU - Montillaud, Julien

AU - Zhang, Chuan Peng

AU - Cunningham, M. R.

PY - 2018/4/1

Y1 - 2018/4/1

N2 - Planck Galactic Cold Clumps (PGCCs) possibly represent the early stages of star formation. To understand better the properties of PGCCs, we studied 16 PGCCs in the L1495 cloud with molecular lines and continuum data from Herschel, JCMT/SCUBA-2, and the PMO 13.7 m telescope. Thirty dense cores were identified in 16 PGCCs from 2D Gaussian fitting. The dense cores have dust temperatures of T d = 11-14 K, and H2 column densities of = (0.36-2.5) × 1022 cm-2. We found that not all PGCCs contain prestellar objects. In general, the dense cores in PGCCs are usually at their earliest evolutionary stages. All the dense cores have non-thermal velocity dispersions larger than the thermal velocity dispersions from molecular line data, suggesting that the dense cores may be turbulence-dominated. We have calculated the virial parameter α and found that 14 of the dense cores have α <2, while 16 of the dense cores have α >2. This suggests that some of the dense cores are not bound in the absence of external pressure and magnetic fields. The column density profiles of dense cores were fitted. The sizes of the flat regions and core radii decrease with the evolution of dense cores. CO depletion was found to occur in all the dense cores, but is more significant in prestellar core candidates than in protostellar or starless cores. The protostellar cores inside the PGCCs are still at a very early evolutionary stage, sharing similar physical and chemical properties with the prestellar core candidates.

AB - Planck Galactic Cold Clumps (PGCCs) possibly represent the early stages of star formation. To understand better the properties of PGCCs, we studied 16 PGCCs in the L1495 cloud with molecular lines and continuum data from Herschel, JCMT/SCUBA-2, and the PMO 13.7 m telescope. Thirty dense cores were identified in 16 PGCCs from 2D Gaussian fitting. The dense cores have dust temperatures of T d = 11-14 K, and H2 column densities of = (0.36-2.5) × 1022 cm-2. We found that not all PGCCs contain prestellar objects. In general, the dense cores in PGCCs are usually at their earliest evolutionary stages. All the dense cores have non-thermal velocity dispersions larger than the thermal velocity dispersions from molecular line data, suggesting that the dense cores may be turbulence-dominated. We have calculated the virial parameter α and found that 14 of the dense cores have α <2, while 16 of the dense cores have α >2. This suggests that some of the dense cores are not bound in the absence of external pressure and magnetic fields. The column density profiles of dense cores were fitted. The sizes of the flat regions and core radii decrease with the evolution of dense cores. CO depletion was found to occur in all the dense cores, but is more significant in prestellar core candidates than in protostellar or starless cores. The protostellar cores inside the PGCCs are still at a very early evolutionary stage, sharing similar physical and chemical properties with the prestellar core candidates.

KW - ISM: clouds

KW - ISM: individual objects (L1495)

KW - ISM: molecules

KW - stars: formation

UR - http://www.scopus.com/inward/record.url?scp=85045553131&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85045553131&partnerID=8YFLogxK

U2 - 10.3847/1538-4357/aaadad

DO - 10.3847/1538-4357/aaadad

M3 - Article

AN - SCOPUS:85045553131

VL - 856

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2

M1 - 141

ER -