X-Ray Flares from an Hα Emission-Line Star in the Orion Region, Kiso A0904–105

[摘要] WeanalyzedASCAdata,includingthereflectionnebulaNGC2023,anddiscoveredtwoX-rayflaresfromanHαemission-linestar,KisoA0904–105,locatedat∼30′tothesouthwestofNGC2023.Theseparationtimebetweenthetwoflareswas∼4hr.Thetemperaturesofthefirstandsecondflaresreached(5–7)×107Kandtheluminositiesaroundtheflarepeakswere∼1033ergs−1(0.5–10.0keVenergyband,assumingthedistanceof400pc),whicharecomparabletothoseofthegiantX-rayflaresfromTTauristars.Aftertheflarepeaks,X-rayintensityexhibitedanexponentialdecay.ComparingtheflareswiththosefromTTauristars,wefoundthatthephysicalparametersintheflaringplasmawerewithintherangeofthoseobtainedfromTTauristars.

[学科分类] 天文学(综合)

[关键词] "stars: flare";"stars: pre-main-sequence";"X-rays: sources";"X-rays: spectra";"X-rays: stars"