Title: The Inclination of the Soft X-ray Transient A0620--00 and the Mass of its Black Hole Show Chinese title

Title: 软X射线暂变体A0620--00的倾角及其黑洞质量

Abstract: We analyze photometry of the Soft X-ray Transient A0620-00 spanning nearly 30 years, including previously published and previously unpublished data. Previous attempts to determine the inclination of A0620 using subsets of these data have yielded a wide range of measured values of i. Differences in the measured value of i have been due to changes in the shape of the light curve and uncertainty regarding the contamination from the disk. We give a new technique for estimating the disk fraction and find that disk light is significant in all light curves, even in the infrared. We also find that all changes in the shape and normalization of the light curve originate in a variable disk component. After accounting for this disk component, we find that all the data, including light curves of significantly different shapes, point to a consistent value of i. Combining results from many separate data sets, we find i=51 plus or minus 0.9 degrees, implying M=6.6 plus or minus 0.25 solar masses. Using our dynamical model and zero-disk stellar VIH magnitudes, we find d=1.06 plus or minus 0.12 kpc. Understanding the disk origin of non-ellipsoidal variability may assist with making reliable determinations of i in other systems, and the fluctuations in disk light may provide a new observational tool for understanding the three-dimensional structure of the accretion disk. Show Chinese abstract

Abstract: 我们分析了软X射线暂变源A0620-00近30年的测光数据，包括之前已发表和未发表的数据。 此前尝试利用这些数据的子集来确定A0620的倾角，得出了i的测量值范围很广的结果。 i的测量值差异是由于光曲线形状的变化以及盘污染的不确定性所致。 我们提出了一种新的估算盘分数的方法，并发现盘光在所有光曲线中都是显著的，即使是在红外波段也是如此。 我们还发现，光曲线形状和归一化的所有变化都源于可变的盘成分。 在考虑了这一盘成分后，我们发现所有数据，包括形状明显不同的光曲线，都指向一个一致的i值。 结合多个独立数据集的结果，我们发现i = 51 ± 0.9度，这意味着M = 6.6 ± 0.25个太阳质量。 使用我们的动力学模型和零盘恒星VIH星等，我们发现d = 1.06 ± 0.12千秒差距。 理解非椭圆变异性中的盘起源可能有助于在其他系统中做出可靠的i值确定，而盘光的波动可能提供一种新的观测工具，以理解吸积盘的三维结构。