Structural Model of Molecular Cloud Complexes: Mass, Size, and External Pressure
[摘要] Weinvestigatethestructureofthemolecularcloudcomplexes(MCCs)asagroupofseveralgiantmolecularclouds(GMCs)intheGalaxy.Wethenfindthatthemass-sizerelationwhichhasbeenreportedfortheGMCsiswell-establishedevenforverylargeMCCs,whosesizesareabout1kpc.SincethehorizontalsizeoftheMCCsislargerthanthethicknessofthegalacticdisk,wecannolongerconsidertheMCCstobespherical.Thus,weconstructastructuralmodeloftheMCCs,adoptingarectangular-solidgeometry.Asaresult,ourmodelexplainstheobservedmass-sizerelationoftheMCCsverywell.FromtheestimatedexternalpressurearoundtheMCCs,wefindthattheyareinaroughpressurebalancewiththeinterstellarmedium.Moreover,wefindthereisanobservationaldeficiencyoftheMCCswithalargesizeandsurfacedensity.WethussuggestthattheexternalpressurehasasignificanteffectonthestructureandevolutionoftheMCCs.WealsodiscusstheeffectofHIIregionsintheMCCs.
[发布日期] [发布机构]
[效力级别] [学科分类] 天文学(综合)
[关键词] "Galaxy: ISM";hydrodynamics;"ISM: clouds";"ISM: structure";"stars: formation" [时效性]
