仙王座B触发星形成区周围的原行星盘演化
Protoplanetary Disk Evolution around the Triggered Star Forming Region Cepheus B
摘要：
仙王座B（CepB）分子云和附近的CepOB 3b OB协会的一部分，是1 kpc内最活跃的恒星形成区域之一，已经被斯皮策太空望远镜上的IRAC探测器观测到。目标是研究该区域的原行星盘演化和连续触发恒星形成的过程。在钱德拉X射线天文台早期观测到的400颗前主序星中，95%的恒星都有中红外光源，其中大部分被归类为无盘星或有盘星。发现了额外的>200个IR过量的低质量成员，给出了一个组合的钱德拉+斯皮策PMS样品，在云外完整的低至0.5 Mo，在云中略高于1 Mo。对几乎圆盘无偏的钱德拉+斯皮策组合恒星样本的分析给出了几个结果。我们的主要发现是年轻恒星从热分子核心到主要电离O星HD 217086的时空梯度。这有力地支持了辐射驱动内爆（RDI）模型的触发恒星形成的区域。经验估计的1公里/秒的冲击速度是非常相似的理论模型RDI在冲击分子云…简短...其他结果包括：1.一致的磁盘分数，它们的质量依赖性，以及过渡磁盘与其他集群的分数; 2.确认嵌入的CepB簇的年轻性; 3.确认在带盘系统与无盘系统中抑制时间积分X射线发射的效果。
英文摘要：
The Cepheus B (CepB) molecular cloud and a portion of the nearby CepOB3b OB association, one of the most active regions of star formation within 1 kpc, have been observed with the IRAC detector on board the Spitzer Space Telescope. The goals are to study protoplanetary disk evolution and processes of sequential triggered star formation in the region. Out of ~400 pre-main sequence (PMS) stars selected with an earlier Chandra X-ray Observatory observation, 95% are identified with mid-infrared sources and most of these are classified as diskless or disk-bearing stars. The discovery of the additional >200 IR-excess low-mass members gives a combined Chandra+Spitzer PMS sample complete down to 0.5 Mo outside of the cloud, and somewhat above 1 Mo in the cloud. Analyses of the nearly disk-unbiased combined Chandra+Spitzer selected stellar sample give several results. Our major finding is a spatio-temporal gradient of young stars from the hot molecular core towards the primary ionizing O star HD 217086. This strongly supports the radiation driven implosion (RDI) model of triggered star formation in the region. The empirical estimate for the shock velocity of 1 km/s is very similar to theoretical models of RDI in shocked molecular clouds...ABRIDGED... Other results include: 1. agreement of the disk fractions, their mass dependency, and fractions of transition disks with other clusters; 2. confirmation of the youthfulness of the embedded CepB cluster; 3. confirmation of the effect of suppression of time-integrated X-ray emission in disk-bearing versus diskless systems.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
