论文标题
形成大量星团的恒星变异性
Stellar Variability in a Forming Massive Star Cluster
论文作者
论文摘要
我们提出了6 \ arcmin $ \ times $ 6 \ arcmin区域的近红外（NIR）可变性分析，该区域涵盖了庞大的原始群集G286.21+0.17。总样本包含5000多个对象，其中562个基于其红外颜色显示出偶有磁盘的迹象。数据包括在F110W和F160W频段中以3年分离的两个时期进行的HST观测值。 363个物体（样品的7％）在显着水平（Stetson Index> 1.7）上表现出NIR的可变性，并且发现具有磁盘过量的年轻恒星对象（YSO）的变异性分数（14％）。我们确定了在两个NIR频段中看到的4个高振幅（> 0.6 mag）变量。此调查中最可变对象的后续和档案观察（G286.2032+0.1740）揭示了从2011年到2019年的8年来上升的光曲线，K带亮点为3.5 mag。总体而言，G286.2032+0.1740的时间行为类似于典型的fu ori对象的时间，但是其前的亮度表明它的质量很低（$ <0.12 \：m_ \ odot $），这使其成为爆炸事件的极端情况。
We present a near-infrared (NIR) variability analysis for an 6\arcmin $\times$ 6\arcmin region, which encompasses the massive protocluster G286.21+0.17. The total sample comprises more than 5000 objects, of which 562 show signs of a circumstellar disk based on their infrared colors. The data includes HST observations taken in two epochs separated by 3 years in the F110W and F160W bands. 363 objects (7% of the sample) exhibit NIR variability at a significant level (Stetson index >1.7), and a higher variability fraction (14%) is found for the young stellar objects (YSOs) with disk excesses. We identified 4 high amplitude (>0.6 mag) variables seen in both NIR bands. Follow up and archival observations of the most variable object in this survey (G286.2032+0.1740) reveal a rising light curve over 8 years from 2011 to 2019, with a K band brightening of 3.5 mag. Overall the temporal behavior of G286.2032+0.1740 resembles that of typical FU Ori objects, however its pre-burst luminosity indicates it has a very low mass ($<0.12\:M_\odot$), making it an extreme case of an outburst event that is still ongoing.
