论文标题
Seyfert Galaxy NGC 5033核中的极端X射线反射
Extreme X-ray Reflection in the Nucleus of the Seyfert Galaxy NGC 5033
论文作者
论文摘要
NGC 5033是一个有趣的Seyfert星系，因为其亚分类可能会随着时间而变化，并且由于光学和亚MM观察结果发现巨大的黑洞不位于银河系的动态中心，指向过去的合并。我们使用Palomar的200'Hale望远镜获得了NGC 5033的新光谱，该光谱清楚地揭示了广泛的H $β$线（FWHM $ = 5400 \ pm 300〜 {\ rm km}〜{\ rm km}〜{\ rm S}}^{ - 1} $）。这标志着光学宽线区域（BLR）的清晰视图，需要Seyfert-1.5名称。过去获得的一些光谱表明SEYFERT-1.9分类，可能会发出变量或“更换”几何形状。我们对2019年大型黑洞Chandra频谱的分析几乎没有晦涩难懂，也表明了中央发动机的清洁视图。但是，狭窄的fe〜k $α$发射线的测量值与ew $ = 460^{+100} _ { - 90} $ 〜ev具有等效。与未探测的AGN中的典型值相比，该值非常高。 Indeed, the line is persistently strong in NGC 5033: the line equivalent width in a 2002 XMM-Newton snapshot is EW$=250^{+40}_{-40}$~eV, similar to the EW$=290^{+100}_{-100}$~eV equivalent width measured using ASCA in 1999. These results can likely be explained through a combination of an反射的异常高覆盖因子，并且由于轻度行进时间而被视为相位的通量。我们研究了NGC 5033可以加强X射线鲍德温效应的证据的可能性。
NGC 5033 is an intriguing Seyfert galaxy because its sub-classification may change with time, and because optical and sub-mm observations find that the massive black hole does not sit at the dynamical center of the galaxy, pointing to a past merger. We obtained a new optical spectrum of NGC 5033 using the 200'' Hale telescope at Palomar that clearly reveals a broad H$β$ line (FWHM$=5400\pm 300~{\rm km}~{\rm s}^{-1}$). This signals a clear view of the optical broad line region (BLR) and requires Seyfert-1.5 designation. Some spectra obtained in the past suggest a Seyfert-1.9 classification, potentially signaling a variable or "changing-look" geometry. Our analysis of a 2019 Chandra spectrum of the massive black hole reveals very little obscuration, also suggesting a clean view of the central engine. However, the narrow Fe~K$α$ emission line is measured to have an equivalent with of EW$=460^{+100}_{-90}$~eV. This value is extremely high compared to typical values in unobscured AGN. Indeed, the line is persistently strong in NGC 5033: the line equivalent width in a 2002 XMM-Newton snapshot is EW$=250^{+40}_{-40}$~eV, similar to the EW$=290^{+100}_{-100}$~eV equivalent width measured using ASCA in 1999. These results can likely be explained through a combination of an unusually high covering factor for reflection, and fluxes that are seen out of phase owing to light travel times. We examine the possibility that NGC 5033 may strengthen evidence for the X-ray Baldwin effect.
