Observational clues for a role of circumstellar accretion in PMS X-ray activity

被引：51

作者：

Flaccomio, E ^{[1
]}

Micela, G ^{[1
]}

Sciortino, S ^{[1
]}

机构：

[1] INAF Osservatorio Astron Palermo Giuseppe S Viana, I-90134 Palermo, Italy

来源：

ASTRONOMY & ASTROPHYSICS | 2003年 / 397卷 / 02期

关键词：

stars : pre-main sequence; X-rays : stars; accretion; accretion disks; open clusters and associations : individual : Orion Nebula Cluster; NGC; 2264; Chamaeleon I;

D O I：

10.1051/0004-6361:20021484

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We revisit the published analyses of ROSAT X-ray observations of the star forming regions NGC 2264 and Chamaeleon I (similar to3 and similar to5 Myr old respectively) in the light of newly published optical data. At odds with previous results on Chamaeleon I members, we find that low mass stars in both regions have near-saturated emission levels. Similarly to what previously found in the Orion Nebula Cluster, Weak Line T-Tauri Stars in NGC 2264 and in the Chamaeleon I cloud have higher X-ray activity levels respect to Classical T Tauri Stars, arguing in favor of a role of the disk and/or accretion in determining X-ray emission.

引用

页码：611 / 621

页数：11

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