低质量活动星系核X射线弱尾的射电审视：高爱丁顿吸积的新特征？
Radio Scrutiny of the X-ray-Weak Tail of Low-Mass Active Galactic Nuclei: A Novel Signature of High-Eddington Accretion?
AI总结：
本研究通过射电与X射线多波长分析，发现低质量高吸积率活动星系核的X射线越弱，射电-X射线光度比越高，提出该特征可作为高吸积率活动星系核的新观测标识。
摘要：
为明亮活动星系核（AGNs）即类星体提供能量的超大质量黑洞（$M_{\rm BH} \sim 10^{6}$$-$$10^{10}~M_\odot$），通常表现出紫外（UV）热盘辐射与硬X射线日冕辐射之间的相关性。相比之下，低质量星系中的一些“大质量”黑洞（mBHs；$M_{\rm BH} \sim 10^{5}$$-$$10^{6}~M_\odot$）呈现出奇特的X射线性质，其日冕辐射输出比预期弱多达100倍。为探究这一问题，我们开展了一项试点研究，利用甚大阵（Very Large Array）射电观测，对18个具有钱德拉（Chandra）X射线观测数据的高吸积率（爱丁顿比$L_{\rm bol}/L_{\rm Edd} > 0.1$）、由mBH驱动的AGN（$M_{\rm BH} \sim 10^{6}~M_\odot$）样本进行了分析。此前在射电宁静、高爱丁顿AGN样本中发现的经验相关性表明，射电-X射线光度比$L_{\rm R}/L_{\rm X}$近似为常数。然而通过多波长分析，我们发现样本中X射线更弱的mBHs倾向于具有更大的$L_{\rm R}/L_{\rm X}$值，尽管根据其光学-紫外性质它们仍属于射电宁静型。这一趋势导致了$L_{\rm R}/L_{\rm X}$与X射线弱度之间一种初步但极具吸引力的相关性，我们认为这与X射线可能被“薄”吸积盘沿我们的视线方向优先遮挡的情景一致。我们将这一观测结果与弱发射线类星体（具有极弱宽线发射且X射线弱比例显著的AGN）进行了比较，最后指出我们的结果可能为寻找高吸积率AGN提供一种新的观测特征。
英文摘要：
The supermassive black holes ($M_{\rm BH} \sim 10^{6}$$-$$10^{10}~M_\odot$) that power luminous active galactic nuclei (AGNs), i.e., quasars, generally show a correlation between thermal disk emission in the ultraviolet (UV) and coronal emission in hard X-rays. In contrast, some "massive" black holes (mBHs; $M_{\rm BH} \sim 10^{5}$$-$$10^{6}~M_\odot$) in low-mass galaxies present curious X-ray properties with coronal radiative output up to 100$\times$ weaker than expected. To examine this issue, we present a pilot study incorporating Very Large Array radio observations of a sample of 18 high-accretion-rate (Eddington ratios $L_{\rm bol}/L_{\rm Edd} > 0.1$), mBH-powered AGNs ($M_{\rm BH} \sim 10^{6}~M_\odot$) with Chandra X-ray coverage. Empirical correlations previously revealed in samples of radio-quiet, high-Eddington AGNs indicate that the radio$-$X-ray luminosity ratio, $L_{\rm R}/L_{\rm X}$, is approximately constant. Through multiwavelength analysis, we instead find that the X-ray-weaker mBHs in our sample tend toward larger values of $L_{\rm R}/L_{\rm X}$ even though they remain radio-quiet per their optical$-$UV properties. This trend results in a tentative but highly intriguing correlation between $L_{\rm R}/L_{\rm X}$ and X-ray weakness, which we argue is consistent with a scenario in which X-rays may be preferentially obscured from our line of sight by a "slim" accretion disk. We compare this observation to weak emission-line quasars (AGNs with exceptionally weak broad-line emission and a significant X-ray-weak fraction) and conclude by suggesting that our results may offer a new observational signature for finding high-accretion-rate AGNs.
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。
