Metal-Rich Plasma at the Center Portion of the Cygnus Loop

Publications of the Astronomical Society of Japan

Miyata, Emi¹  Kohmura, Takayoshi¹  Tsunemi, Hiroshi¹  Suzuki, Seiji¹  Kumagai, Shiomi² 

[1] Department of Earth and Space Science, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 E-mail(EM):;Department of Physics, College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062

关键词: Abundances;    Nucleosynthesis;    "Supernovae;    Supernova remnants";    "X-rays: spectra";   

DOI  :  10.1093/pasj/50.2.257

学科分类：天文学(综合)

来源: Oxford University Press

【 摘 要 】

WeobservedthecenterportionoftheCygnusLoopsupernovaremnantwiththeASCAobservatory.TheX-rayspectrumofthecenterportionwassignificantlydifferentfromthatobtainedattheNorth-East(NE)limb.TheemissionlinesfromSiandSwerequitestrong,whilethoseofOandthecontinuumemissionweresimilartothoseobtainedattheNElimb.Basedonaspectralanalysis,theSiandSemissionlinesoriginatedfromahigh-kTeandlow-ionizationplasma,whereasOandmostofthecontinuumemissionarosefromalow-kTeandhigh-ionizationplasma.WesupposethatSiandSemittinggasesarepresentattheinterioroftheLoop,whiletheOlinesandcontinuumemissionmainlyarisefromtheshellregion.Therefore,wesubtractedthespectrumoftheNElimbfromthatofthecenter.TheobtainedabundancesofSi,S,andFewere4±1,6±2,and$$1.3^{+0.6}_{-0.3}$$timeshigherthanthoseofthecosmicabundances,respectively,and∼40timesricherthanthoseobtainedattheNElimb.ThesefactsstronglysupporttheideathatsomeofthecrudeejectamustbeleftatthecenterportionoftheCygnusLoop.ThelowabundanceofFerelativetoSiandSsuggestsatypeIISNwithamassiveprogenitorstarastheoriginoftheCygnusLoop.

【 授权许可】

Unknown