A COMPARATIVE STUDY OF GIANT MOLECULAR CLOUDS IN M51, M33, AND THE LARGE MAGELLANIC CLOUD

被引：163

作者：

Hughes, Annie ^{[1
]}

Meidt, Sharon E. ^{[1
]}

Colombo, Dario ^{[1
]}

Schinnerer, Eva ^{[1
]}

Pety, Jerome ^{[2
,3
]}

Leroy, Adam K. ^{[4
]}

Dobbs, Clare L. ^{[5
]}

Garcia-Burillo, Santiago ^{[6
]}

Thompson, Todd A. ^{[7
,8
]}

Dumas, Gaelle ^{[2
]}

Schuster, Karl F. ^{[2
]}

Kramer, Carsten ^{[9
]}

机构：

[1] Max Planck Inst Astron, D-69117 Heidelberg, Germany

[2] Inst Radioastron Milimetr, F-38406 St Martin Dheres, France

[3] Observ Paris, F-75014 Paris, France

[4] Natl Radio Astron Observ, Charlottesville, VA 22903 USA

[5] Univ Exeter, Sch Phys & Astron, Exeter EX4 4QL, Devon, England

[6] Observ Madrid, Observ Astron Nacl, E-28040 Madrid, Spain

[7] Ohio State Univ, Dept Astron, Columbus, OH 43210 USA

[8] Ohio State Univ, Ctr Cosmol & AstroParticle Phys, Columbus, OH 43210 USA

[9] Inst Radioastron Milimetr, E-18012 Granada, Spain

来源：

ASTROPHYSICAL JOURNAL | 2013年 / 779卷 / 01期

基金：

欧洲研究理事会;

关键词：

galaxies:; individual; (M51; M33; Large Magellanic Cloud); galaxies: ISM; ISM: clouds; ISM: molecules; ISM: structure; CO-TO-H-2 CONVERSION FACTOR; DWARF SEYFERT NUCLEI; ON SPIRAL GALAXIES; ALL-DISK SURVEY; STAR-FORMATION; NEARBY GALAXIES; VELOCITY DISPERSION; INTERSTELLAR-MEDIUM; H-I; LOCAL GROUP;

D O I：

10.1088/0004-637X/779/1/46

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We compare the properties of giant molecular clouds (GMCs) in M51 identified by the Plateau de Bure Interferometer Whirlpool Arcsecond Survey with GMCs identified in wide-field, high-resolution surveys of CO emission in M33 and the Large Magellanic Cloud (LMC). We find that GMCs in M51 are larger, brighter, and have higher velocity dispersions relative to their sizes than equivalent structures in M33 and the LMC. These differences imply that there are genuine variations in the average mass surface density <Sigma(H2)> of the different GMC populations. To explain this, we propose that the pressure in the interstellar medium surrounding the GMCs plays a role in regulating their density and velocity dispersion. We find no evidence for a correlation between size and linewidth in M51, M33, or the LMC when the CO emission is decomposed into GMCs, although moderately robust correlations are apparent when regions of contiguous CO emission (with no size limitation) are used. Our work demonstrates that observational bias remains an important obstacle to the identification and study of extragalactic GMC populations using CO emission, especially in molecule-rich galactic environments.

引用

页数：20

共 105 条

[41] GIANT MOLECULAR CLOUDS IN THE SPIRAL ARM OF IC 342 [J].