Investigating the Evolution of Amati Parameters with Redshift  

作　　者：Meghendra Singh Darshan Singh Kanhaiya Lal Pandey Dinkar Verma Shashikant Gupta 

机构地区：[1]Delhi Metro Rail Corporation Limited,New Delhi 110001,India [2]GD Goenka University,Gurugram 122103,India [3]Department of Physics,Mata Raj Kaur Institute of Engineering and Technology,Rewari 123401,India [4]Department of Physics,School of Advanced Sciences,Vellore Institute of Technology,Vellore 632014,India

出　　处：《Research in Astronomy and Astrophysics》2024年第1期188-200,共13页天文和天体物理学研究（英文版）

基　　金：M.S.thanks DMRC for support;D.S.thanks the compeers of GD Goenka University for continuing assistance.

摘　　要：Gamma-ray bursts(GRBs) are among the brightest objects in the Universe and, hence, can be observed up to a very high redshift. Properly calibrated empirical correlations between intensity and spectral correlations of GRBs can be used to estimate the cosmological parameters. However, the possibility of the evolution of GRBs with redshift is a long-standing puzzle. In this work, we used 162 long-duration GRBs to determine whether GRBs below and above a certain redshift have different properties. The GRBs are split into two groups, and we fit the Amati relation for each group separately. Our findings demonstrate that estimations of the Amati parameters for the two groups are substantially dissimilar. We perform simulations to investigate whether the selection effects could cause the difference. Our analysis shows that the differences may be either intrinsic or due to systematic errors in the data, and the selection effects are not their true origin. However, in-depth analysis with a new data set comprised of 119 long GRBs shows that intrinsic scatter may partly be responsible for such effects.

关 键 词：COSMOLOGY gamma rays:general (cosmology:)large-scale structure of universe galaxies:high-redshift 

分 类 号：P172.3[天文地球—天文学]