Threshold between Spontaneous and Cloud-Collisional Star Formation

Publications of the Astronomical Society of Japan

Sofue, Yoshiaki¹  Egusa, Fumi¹  Shinya, Komugi¹ 

[1]Institute of Astronomy, The University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo, 181-8588

关键词: "galaxies: ISM";    "ISM: molecules";    "stars: formation";   

DOI  :  10.1093/pasj/58.5.793

学科分类：天文学(综合)

来源: Oxford University Press

【 摘 要 】

Basedonsimplephysicalandgeometricassumptions,wehavecalculatedthemeansurfacemoleculardensityofspiralgalaxiesatthethresholdbetweenstarformationinducedbycloud-cloudcollisionandspontaneousgravitationalcollapse.Thecalculatedthresholdisapproximately$$logSigma_mathrm{crit}sim2.5$$,where$$Sigma;[{{{M}_{odot}}},mathrm{pc}^{-2}]$$istheobservedsurfacemassdensityofanassumedflatgasdisk.Abovethislimit,therateofmolecularcloudcollisionsdominatesoverspontaneousmolecularcloudcollapse.ThismodelmayexplaintheapparentdiscontinuityintheSchmidtlawfoundrecentlyat$$2lesssimlogSigmalesssim3$$.

【 授权许可】

Unknown