X-Ray Analysis of the ρ Ophiuchi Dark Cloud with ASCA : Source Identification, X-Ray Spectra, and Temporal Variability
X-Ray Analysis of the ρ Ophiuchi Dark Cloud with ASCA : Source Identification, X-Ray Spectra, and Temporal Variability
复制标题
使用 ASCA 对蛇夫座 ρ 暗云进行 X 射线分析：源识别、X 射线光谱和时间变化
DOI：
--
复制
发表时间：
1997
期刊：
影响因子：
--
通讯作者：
S. Yamauchi
中科院分区：
文献类型：
--
作者：
Y. Kamata;K. Koyama;Y. Tsuboi;S. Yamauchi
本文介绍了日本X射线天文卫星ASCA对蛇夫座p星云主体X射线的综合研究。我们使用3个能带和12个时间切片数据构建了单独的X射线图像，从而检测到19个X射线源，是之前ASCA结果的11个X射线源的两倍。其中三个源与I类红外源有关，它们先于金牛座T阶段。发现19个源中有一半是时变的，并观察到5个平均能量> 3 × 1035 erg的耀斑样事件。通过与太阳耀斑的类比，我们估计耀斑环的高度和等离子体密度分别为3 × 10 ~（11）cm ~（-3）和3 × 10 ~（11）cm ~（-3）。在这些源中，来自I类源EL 29的耀斑表现出比静止状态大一个数量级的吸收（A/H），这可能表明存在致密的原恒星盘。
This paper presents a comprehensive study with the Japanese X-ray astronomical satellite ASCA on X-rays from the main body of the p Ophiuchi dark cloud. We have constructed separate X-ray images using 3 energy bands and 12 time-sliced data, and thereby detected 19 X-ray sources, doubling the previous ASCA results of 11 X-ray sources. Three of the sources are associated with class-I infrared sources, which precede the T Tauri phase. Half of the 19 sources were found to be time variable, and 5 flare-like events with an averaged energy of > 3 x 1035 erg were observed. With the analogy of solar flares, we estimated the flare loop height and plasma density to be 3 x 1011 cm and 3 x 1011 cm -3 , respectively. Among these sources, a flare from the class-I source EL 29 exhibited an order-of-magn itude larger absorption (A/H) than in quiescence states, which may indicate the exsistence of a dense protostellar disk.