将M31 X射线系统RX J0042 .3+4115恢复为黑洞X射线双星，以及扩展日冕的令人信服的证据
Reinstating the M31 X-ray system RX J0042.3+4115 as a black hole X-ray binary, and compelling evidence for an extended corona
摘要：
M31 X射线源RX J0042.3+4115最初被认为是一个黑洞双星，因为它在显著的高光度下表现出低的状态变化;不幸的是，这种变化后来被发现是人为的。然而，对84个钱德拉ACIS观测、一个HST ACS/WFC观测和一个60 ks XMM-牛顿观测的分析提供了新的证据，表明RX J0042.3+4115确实是一个黑洞双星。在RX J0042.3+4115位置3 σ范围内最亮的光学星的F435 W（~B）星等为25.4+/-0.2; M_B >-0.4，因此我们认为可能存在一个低质量施主。RX J0042.3+4115持续明亮约12年。光谱拟合揭示了典型的黑洞二元态：低/硬态在2.08+/-0.08 E+38 erg/s，陡峭的幂律态在2.41+/-0.05 E+38 erg/s（0.3--10 keV）。高光度的低状态表明一个~20 M_太阳的主要;这是高的，但在已知的恒星黑洞质量的范围内。在陡峭的幂律状态下的内部磁盘温度为2.24 $\pm$ 0.15 keV，高，但惊人的相似，GRS 1915+105，唯一已知的银河系黑洞二进制与低质量的捐助者要持久明亮。因此，RX J0042.3+4115可能是GRS 1915+105的类似物;然而，其他机制可能解释其行为。我们发现了令人信服的证据，扩展电晕在陡峭的幂律状态，因为紧凑的电晕模型，其中种子光子康普顿化的内部光盘温度被拒绝。
英文摘要：
The M31 X-ray source RX J0042.3+4115 was originally identified as a black hole binary because it displayed characteristic low state variability at conspicuously high luminosities; unfortunately, this variability was later found to be artificial. However, analysis of 84 Chandra ACIS observations, an HST ACS/WFC observation, and a 60 ks XMM-Newton observation has supplied new evidence that RX J0042.3+4115 is indeed a black hole binary. The brightest optical star within 3 sigma of the position of RX J0042.3+4115 had a F435W (~B) magnitude of 25.4+/-0.2; M_B > -0.4, hence we find a low mass donor likely. RX J0042.3+4115 was persistently bright over ~12 years. Spectral fits revealed characteristic black hole binary states: a low/hard state at 2.08+/-0.08 E+38 erg/s, and a steep power law state at 2.41+/-0.05 E+38 erg/s (0.3--10 keV). The high luminosity low state suggests a ~20 M_Sun primary; this is high, but within the range of known stellar black hole masses. The inner disk temperature during the steep power law state is 2.24$\pm$0.15 keV, high but strikingly similar to that of GRS 1915+105, the only known Galactic black hole binary with a low mass donor t o be persistently bright. Therefore RX J0042.3+4115 may be an analog for GRS 1915+105; however, other mechanisms may account for its behavior. We find compelling evidence for an extended corona during the steep power law state, because compact corona models where the seed photons for Comptonization are tied to the inner disc temperature are rejected.
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。
