Presidential Young Investigator Award-Active Galactic Nuclei and Supernovae

我们将从观测的角度结合理论计算来研究类星体、活动星系、超新星和X射线双星中发生的物理条件和过程。许多研究将涉及开发复杂的图像处理数据分析技术，以及吸积盘和电离气体的精确数值模型。在某些情况下，这些方法可能适用于许多非天文研究领域。主要目标之一是确定附近的星系是否以任何方式与发光的类星体有关。人们普遍认为，类星体的能量来自于星系中心超大质量黑洞上积累的物质。如果是这样的话，很可能至少有一些局部星系是“死的”类星体，因此它们的核心里有这样的黑洞。类似地，在一些星系中，即使过去不是发光的类星体，类星体现象也可能发生在较低的本征能级。我们将分析在过去几年中观测到的500个明亮星系核的高质量光谱。在仔细去除恒星连续体和吸收线之后，通常可以看到微弱的发射线。还将开展超新星(SNE)研究。北方望远镜可获得的每一个明亮SN的一长串光度学光谱将用于统计研究(前身恒星、与环境的相关性等)。与理论模型的预测进行比较，将有助于了解膨胀气体的化学成分和激发机制，以及恒星爆炸的性质。人们将尝试确定X射线双星的物理特征，这些双星经常显示出与活动星系核有趣的相似之处。最重要的问题之一是SS433的中心天体是黑洞还是中子星。吸积盘的性质以及它承受强迫进动的机制，也是需要解决的突出问题。

The physical conditions and processes that occur in quasars (QSOs), active galaxies, supernovae, and X-ray binary stars will be investigated from an observational point of view, coupled with theoretical calculations. Much of the research will involve the development of sophisticated image processing data analysis techniques, as well as accurate numerical models of accretion disks and ionized gases. In some cases the methods may become applicable to many non- astronomical research areas. One of the main goals is to determine whether nearby galaxies are in any way related to luminous QSOs. It is generally believed that QSOs derive their energy from matter accreting onto supermassive black holes in the centers of galaxies. If so, it is likely that at least some local galaxies are "dead" QSOs, and therefore harbor such black holes in their nuclei. Similarly, the QSO phenomenon may occur at a low intrinsic level in some galaxies even if thy were not luminous QSOs in the past. High-quality optical spectra of the nuclei of 500 bright, nearby galaxies, observed during the past few years will be analyzed. After careful removal of the underlying stellar continuum and absorption lines, faint emission lines are usually visible. The study of supernovae (SNe) will also be carried out. A long series of photometric optical spectra of every bright SN accessible to northern telescopes will be used in statistical studies (progenitor stars, correlations with environment, etc.). Comparison with the predictions of theoretical models should shed light on the chemical composition and excitation mechanism of the expanding gas as well as on the nature of the stellar explosion. There will be an attempt to determine the physical characteristics of X-ray binaries, which often show interesting parallels with active galactic nuclei. One of the most important questions is whether the central object in SS 433 is a black hole or a neutron star. The nature of the accretion disk, and the mechanism by which it undergoes forced precession, are also outstanding problems that should be solved.