Ia型超新星的消光改正

发布时间：2018-03-31 18:52

本文选题：超新星　切入点：Ia型超新星　出处：《天文学进展》2015年02期

【摘要】：Ia型超新星因其在宇宙学上起着标准烛光的作用而备受关注,正确的消光改正才能还原其本征亮度和颜色,然后才能在宇宙学中恰当地应用。综述了不同环境中的尘埃对Ia型超新星消光的影响,并讨论Ia型超新星绝对星等的校正和Rv值偏小的原因。Ia型超新星绝对星等的弥散主要受两个方面的影响,一是由前身星状态所导致的固有弥散,二是寄主星系内尘埃的消光。利用与距离无关的参数对绝对星等校正后,可以将弥散降低到0.1 mag以下。Ia型超新星的内禀色指数呈现出随时间演化的一致性,使得其红化比较容易计算。大量的观测和分析表明,Ia型超新星在寄主星系中的Rv值在低红化时,其情形比较接近银河系;而在红化严重时偏小,多在2.0以下,低于银河系的平均值3.1。一种可能的解释是Ia型超新星的星周尘埃对星光的多重散射,另一种可能是Ia型超新星寄主星系的尘埃与典型的银河系内星际尘埃的差异。
[Abstract]:Type Ia supernova has attracted much attention for its role as standard candlelight in cosmology. Correct extinction correction can restore its intrinsic brightness and color. The effects of dust in different environments on the extinction of type Ia supernova are reviewed. It is also discussed that the correction of absolute magnitude of type Ia supernova and the reason that the RV value is small. The dispersion of absolute magnitude of type Ia supernova is mainly affected by two aspects, one is the inherent dispersion caused by the former star state. The other is the extinction of dust in host galaxies. After the absolute magnitude is corrected by the distance independent parameters, the intrinsic color index of the supernova can be reduced to less than 0. 1 mag. The intrinsic color index of the Ia type supernova shows a consistent evolution over time. A large number of observations and analyses show that the Rv value of Ia supernova in host galaxies is similar to that of the Milky way galaxy when it is low reddish, but is smaller than 2.0 in severe redness. One possible explanation is the multiple scattering of stars by the circumstellar dust of the Ia supernova, and the other is the difference between the dust of the host galaxy of the type Ia supernova and the interstellar dust of the typical intergalactic system.
【作者单位】：北京师范大学天文系;
【基金】：国家自然科学基金(11373015) 973项目(2014CB845702)
【分类号】：P145.3

【参考文献】