ASCA Observations of the NGC 2264 Molecular Cloud

[摘要] WehavemadeASCAobservationsofthemolecularcloudassociatedwithNGC2264,anddetectednineandfivesourcesinthesoftandhardX-raybandimages,respectively.Mostofthemareidentifiedwithknownpre-main-sequencestarsorprotostellarobjects.TwoClassIsourceswithintermediateluminositiesandoneClassIIsourceassociatedwithmolecularoutflowarepromisingcandidatesforX-rayemitters.Anopticallythinhot-plasmamodelwithtwocomponentscanreproducetheGISX-rayspectra,includingbothoftheClassIsources.ThehardX-raysprobablyarisefromtheseClassIsources,andareintrinsicallyveryluminous,gt;1032ergs−1inthe0.7–10.0keVenergyband,andtheirluminositiesliebetweenlow-massClassIsourcesandthatoftheW3massivecoreregion.Sincenear-infraredsurveydatarevealthatClassIsourcesaresurroundedbyembeddedyoungclusters,thesoftX-raycomponentscouldbeexplainedbyaggregatesoflow-masspre-main-sequencestars.

[学科分类] 天文学(综合)

[关键词] "open clusters and associations: individual (NGC 2264)";"stars: pre-main sequence";"X-rays: stars";"X-rays: sources";"X-rays: spectra"