标题： 年轻大质量星团VVV CL077的X射线源初步研究 显示英文标题

标题： A First Look at the X-ray Population of the Young Massive Cluster VVV CL077

摘要： 对年轻的巨大星团VVV CL077的多波长分析首次被提出。 我们的钱德拉巡天使该区域的三个X射线发射恒星成员得以被检测到，同时还可能检测到一个从星团核心延伸几个角秒的弥漫X射线成分，在0.5-10 keV波段的固有流量为(9+/-3)x10^-14 erg cm^-2 s^-1。 我们获得的这两个X射线点源的红外光谱显示了典型的大质量O型恒星大气吸收线。 从可见范围的VVV CL077，即围绕星团15"半径的范围内的X射线光谱可以用一个吸收幂律模型来描述，nH = (6+/-4)x10^22 cm^-2，gamma = 2+/-1。 此外，VVV CL077的X射线核心与红外波段看到的弥散辐射以及射电连续谱图中的局部最大值相吻合。 与邻近的H II区可能的关联将把VVV CL077置于约11 kpc的距离；在Norma臂的远侧。 在这个距离上，这个星团宽0.8 pc，质量密度为(1-4)x10^3 Msol pc^-3。 显示英文摘要

摘要： Multi-wavelength analysis of the young massive cluster VVV CL077 is presented for the first time. Our Chandra survey of this region enabled the detection of three X-ray emitting stellar members of the cluster, as well as a possible diffuse X-ray component that extends a few arcseconds from the cluster core with an intrinsic flux of (9+/-3)x10^-14 erg cm^-2 s^-1 in the 0.5-10 keV band. Infrared spectra we obtained for two of these X-ray point sources show absorption lines typical of the atmospheres of massive O stars. The X-ray spectrum from the visible extent of VVV CL077 i.e., a 15"-radius around the cluster, can be modeled with an absorbed power law with nH = (6+/-4)x10^22 cm^-2 and gamma = 2+/-1. In addition, the X-ray core of VVV CL077 coincides with diffuse emission seen in the infrared band and with a local maximum in the radio continuum map. A possible association with a neighboring H II region would place VVV CL077 at a distance of around 11 kpc; on the far side of the Norma Arm. At this distance, the cluster is 0.8 pc wide with a mass density of (1-4)x10^3 Msol pc^-3.