A CO survey of the LMC with NANTEN: II. Catalog of molecular clouds

被引:117
作者
Mizuno, N [1 ]
Yamaguchi, R
Mizuno, A
Rubio, M
Abe, R
Saito, H
Onishi, T
Yonekura, Y
Yamaguchi, N
Ogawa, H
Fukui, Y
机构
[1] Nagoya Univ, Dept Astrophys, Chikusa Ku, Nagoya, Aichi 4648602, Japan
[2] Univ Chile, Dept Astron, Santiago, Chile
[3] Osaka Prefecture Univ, Dept Earth & Life Sci, Sakai, Osaka 5998531, Japan
[4] Nobeyama Radio Observ, Minamisa Ku, Nagano 3841305, Japan
关键词
galaxies : ISM; galaxies : Magellanic Clouds; ISM : clouds; radio lines : ISM;
D O I
10.1093/pasj/53.6.971
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
From a (CO)-C-12 (J = 1-0) survey with the NANTEN telescope, we present a complete catalog of giant molecular clouds (GMCs) in the Large Magellanic Cloud. In total, 107 CO clouds have been identified, 55 of which were detected at more than 3 observed positions. For the 55 clouds, the physical properties, such as size, line-width, virial mass, and CO luminosity, are cataloged. From a statistical analysis of these quantities, we show that GMCs in the LMC are close to gravitational equilibrium. A comparison with Hi data indicates that most of the CO clouds are distributed in dense parts of 14 1 gas, whose H I column density is greater than 10(21) cm(-2). It is notable that the mass ratio of the molecular-to-atomic hydrogen of the lower radial velocity component of gas is similar to 0.2, which is a factor of 2 higher than Chat of the gaseous-disk component, similar to 0.1. Molecular clouds are apparently formed efficiently in the parent atomic clouds in the lower velocity component. The CO Arc, which is a few kpc scale ordered structure of CO clouds along the southern optical edge of the galaxy, corresponds well to the the lower velocity component of HI gas.
引用
收藏
页码:971 / 984
页数:14
相关论文
共 62 条
[1]   CO-to-H-2: Conversion factor in galaxies [J].
Arimoto, N ;
Sofue, Y ;
Tsujimoto, T .
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, 1996, 48 (02) :275-284
[2]   Integrated UBV photometry of 624 star clusters and associations in the Large Magellanic Cloud [J].
Bica, E ;
Claria, JJ ;
Dottori, H ;
Santos, JFC ;
Piatti, AE .
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 1996, 102 (01) :57-73
[3]  
BLOEMEN JBGM, 1986, ASTRON ASTROPHYS, V154, P25
[4]   Star formation activity in the large magellanic cloud: Far-infrared emission from IRAS high-resolution data [J].
Caldwell, DA ;
Kutner, ML .
ASTROPHYSICAL JOURNAL, 1996, 472 (02) :611-623
[5]  
CASOLI F, 1984, ASTRON ASTROPHYS, V133, P99
[6]   A COMPLETE CO SURVEY OF THE LARGE MAGELLANIC CLOUD [J].
COHEN, RS ;
DAME, TM ;
GARAY, G ;
MONTANI, J ;
RUBIO, M ;
THADDEUS, P .
ASTROPHYSICAL JOURNAL, 1988, 331 (02) :L95-L99
[7]   MAXIUM-LIKELIHOOD ESTIMATION OF SLOPE FROM NUMBER-FLUX-DENSITY COUNTS OF RADIO SOURCES [J].
CRAWFORD, DF ;
JAUNCEY, DL ;
MURDOCH, HS .
ASTROPHYSICAL JOURNAL, 1970, 162 (02) :405-&
[8]   THE LARGEST MOLECULAR CLOUD COMPLEXES IN THE 1ST GALACTIC QUADRANT [J].
DAME, TM ;
ELMEGREEN, BG ;
COHEN, RS ;
THADDEUS, P .
ASTROPHYSICAL JOURNAL, 1986, 305 (02) :892-&
[9]  
Davies R.D., 1976, MEM R ASTRON SOC, V81, P89
[10]  
de Boer KS, 1998, ASTRON ASTROPHYS, V338, pL5