大质量恒星形成核区多谱线的观测研究-ThesisMod

UDC800212007S152007.82007.8-2-Shirleyetal200363CSJ=5-4Spitzer24200513.712CO,13COC18OJ=1-0C18O1515LTEC18O13COLTE12CO12CO13COR12=132.5-4.513COC18OR13=184-206-1212COC18OR12=1813-9013-50FCRAOHCNCSC18O13COC18OHCNCSC18OHCNCS13COHCNCSC18OHCNCSC18O13COHCN-i-AbstractABSTRACTDirectedby:YuGaoThesisby:LiyunZhangSimultaneousobservationsof12C,13COandC18Olineemissionwerecarriedouttowards24Galactichigh-massstarformingcoresinNovember2005withthe13.7mmillimeterwavetelescopeofPurpleMountainOb-servatoryattheQinghaiStation.ThesecoresareassociatedwithwatermasersandasselectedfromShirleyetal(2003)'ssampleof63coreswiththeobservationofCS(J=5-4)andarealsoobservedbytheSpitzer.Inoursample15coresweremappedwithintheregionswhereC18Ointegratedin-tensityreachesthehalfmaximum,whiletherestwerenotobservedwithsolargescaleofmappingbecauseofthelowsignal-to-noiseratioortheintrin-sicallyextendedmorphologyofthecores.Wealsocalculatedthephysicalparametersofthese15fullymappeddensecoresincludingthemass,thesize,thecolumndensity,opticaldepth,andaveragenumberdensityandsoon.Wecomparedanddiscussedthecharateristicsofthe15fullyobservedcoresbaseduponanalysis.ThevirialmassissmallerthantheLTEmass,andtheratioofvirialmasstoLTEmassforC18Oissmallerthanthatfor13CO.Ingeneral,theintegratedintensityratiosof12COtoitsisotropesgraduallyincreasesfromtheinnermosttotheouterpartofthecoresforeachdensecores.Wefoundthattheratioof12COto13CO(R12=13)rangesmostlyfrom2.5to4.5;fortheratioof13COtoC18O(R13=18)itrangesfrom4to20withsmall°uctuationof6-12intheinnerpartofthecores;theratioof12COtoC18O(R12=18)is13-90,andtypically13-50inthedenserregionsofthecores.OurC18OcoresdonotnecessarillymatchthecorrespondingcoresofHCNandCSmapsobservedwithFCRAO14mbyWuetal(2005).Bycomparingtheluminositiesofthesefourmolecularspectrallines,thecorrelationbetweenluminosityofC18OandHCNorCSistighterthanthatbetween13CO'sluminosityandHCNorCS's.We-ii-AbstractalsoconcludedthattheluminosityofC18Oor13COhavealoosercorrela-tionwiththeIRluminositythanHCNthoughthereseemstobeacertaincorrelationbetweenthetheIRluminosityandC18Oor13CO'sluminosity.KeywordISM:clouds|radiolines:ISM|stars:formation|luminosity:IR|ratio:molecularlineemission-iii-.........................................................11.1.......................................................11.1.1..................................................31.1.2..................................................31.1.3.....................................................41.2...........................................51.3...........................................................51.4................................................7.........................................................102.1..............................................................102.2.........................................................13..............................................183.1................................................................183.2................................................................203.3..................................................293.3.1..............................................293.3.2.......................................................343.4................................................3513COC18OHCNCS..........414.1HCNCS.................................................414.2C18OHCNCS..........................424.313COC18OHCNCS...............................524.413COC18O.....................................57.........................................................615.1................................................................615.2...........................................................62.........................................................64.............................................................79.........................................83.................................................................84-iv-2-113COC18O......................................152-213COC18O......................................162-313COC18O......................................173-112CO..............................................183-212CO..............................................193-313COC18O............................................203-413COC18O............................................213-513COC18O............................................223-613COC18O............................................233-713COC18O............................................243-813COC18O............................................253-913COC18O............................................263-1013COC18O...........................................273-11LTE............................343-12CO..........384-1C18OCSHCN................................454-2C18OCSHCN................................464-3C18OCSHCN................................474-4C18OCSHCN................................484-5C18OCSHCN................................494-6C18OCSHCN................................504-7C18OCSHCN................................514-8C18O13CO.........................................