Another Abundance Inhomogeneity in the South East Limb of the Cygnus Loop

摘要

Weobservedthesoutheast(SE)limboftheCygnusLoopwithSuzaku.Ourspatially-resolvedspectroscopicstudyshowsthataone-$$kT_mathrm{e}$$non-equilibriumionizationmodelrepresentsourspectrafairlywell.WefindthatthemetalabundancesobtainedarealldepletedrelativetothesolarvalueswithapositionaldependencealongtheradialdirectionoftheCygnusLoop.Theabundancesintheveryedgeofthelimbshowabouthalfthesolarvalue,whereasotherregionsinsidetheLoopshowabout0.2-timesthesolarvalue,whichhasbeenbelievedtobeatypicalvaluefortheCygnusLooplimb.Thea€?enhanceda€?abundanceintheveryedgeoftheSElimbisquitesimilartothatfoundinthenorth-east(NE)limboftheLoop,andthusthisisanotherevidenceofanabundanceinhomogeneityinthelimbregionsoftheLoop.Theradiomapshowsaquitedifferentfeature:theNElimbisintheradiobrightregion,whiletheSElimbshowsalmostnoradio.Therefore,themetalabundancevariationintheSElimbcannotbeattributedtonon-thermalemission.Theabundanceinhomogeneityaswellasthemetaldepletiondownto0.2timesthesolarvaluestillremainanopenquestion.