天文学进展2017，Vol.35Issue(4)：398-416,19.DOI:10.3969/j.issn.1000-8349.2017.04.02
活动星系核X射线本征谱指数与爱丁顿比关系的研究进展
Research Progress on the Correlation Between X-ray Intrinsic Photon Index and Eddington Ratio in Active Galactic Nuclei
摘要
Abstract
Active galactic nuclei (AGN) are galaxies that have strong activities at their centers. Due to continual progress in observational technologies, a wide variety of researches on AGN have been carried out, leading to profound understanding of the nature of AGN. This paper collects and summarizes recent observational results about the correlation between X-ray intrinsic photon index and Eddington ratio in AGN, which present a V-shape correlation:as the Eddington ratio decreases continuously, such a correlation changes from being positive into being negative. It is generally believed that these observational results reflect that, as the accretion rate decreases, the black hole accretion mode changes as well, from the original standard thin disk into radiatively ine?cient accretion flow. This indicates that the very basic AGN unification models based on the standard thin accretion disk have to be modified in order to well explain some observed properties of the low-luminosity AGN, although those models enjoy great success in explaining many observations of the AGN with higher luminosities. In the future, it is possible to use this correlation (if refined further) to estimate some important AGN parameters such as the black hole mass and accretion rate, which will facilitate our better understanding of the radiation mechanisms and evolution of AGN. Finally, this paper is concluded with some future prospects in this research field.关键词
活动星系核/X射线天文学/吸积物理Key words
AGN/X-ray astronomy/accretion physics分类
天文与地球科学引用本文复制引用
倪嘉阳,薛永泉..活动星系核X射线本征谱指数与爱丁顿比关系的研究进展[J].天文学进展,2017,35(4):398-416,19.基金项目
国家自然科学基金(11473026,11421303) （11473026,11421303）
973项目(2015CB857004) （2015CB857004）
中国科学院战略性先导科技专项(XDB09000000) （XDB09000000）
中央高校基本科研业务费专项资金 （）
中国科学院前沿科学重点研究项目(QYZDJ-SSW-SLH006) （QYZDJ-SSW-SLH006）
