Structural model of molecular cloud complexes: Mass, size, and external pressure

Akio K. Inoue*, Hideyuki Kamaya

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)


We investigate the structure of the molecular cloud complexes (MCCs) as a group of several giant molecular clouds (GMCs) in the Galaxy. We then find that the mass-size relation which has been reported for the GMCs is well-established even for very large MCCs, whose sizes are about 1 kpc. Since the horizontal size of the MCCs is larger than the thickness of the galactic disk, we can no longer consider the MCCs to be spherical. Thus, we construct a structural model of the MCCs, adopting a rectangular-solid geometry. As a result, our model explains the observed mass-size relation of the MCCs very well. From the estimated external pressure around the MCCs, we find that they are in a rough pressure balance with the interstellar medium. Moreover, we find there is an observational deficiency of the MCCs with a large size and surface density. We thus suggest that the external pressure has a significant effect on the structure and evolution of the MCCs. We also discuss the effect of H II regions in the MCCs.

Original languageEnglish
Pages (from-to)L47-L51
JournalPublications of the Astronomical Society of Japan
Issue number6
Publication statusPublished - 2000
Externally publishedYes


  • Galaxy: ISM
  • Hydrodynamics
  • ISM: clouds
  • ISM: structure
  • Stars: formation

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'Structural model of molecular cloud complexes: Mass, size, and external pressure'. Together they form a unique fingerprint.

Cite this