X-Ray Plateaus in Gamma-Ray Burst Afterglows and Their Application in Cosmology

• Published in: The Astrophysical journal Vol. 920; no. 2; pp. 135 - 153
• Main Authors: Xu, Fan, Tang, Chen-Han, Geng, Jin-Jun, Wang, Fa-Yin, Wang, Yu-Yang, Kuerban, Abudushataer, Huang, Yong-Feng
• Format: Journal Article
• Language: English
• Published: Philadelphia The American Astronomical Society 01.10.2021; IOP Publishing
• Subjects: Afterglows; Astronomical models; Astrophysics; Constraint modelling; Correlation; Cosmological parameters; Cosmology; Dark energy; Dark matter; Evolution; Gamma ray bursts; Gamma rays; Legal issues; Luminosity; Neutron stars; Parameters; Plateaus; Red shift; X-rays
• ISSN: 0004-637X; 1538-4357
• DOI: 10.3847/1538-4357/ac158a

Abstract For gamma-ray bursts (GRBs) with a plateau phase in the X-ray afterglow, a so-called L – T – E correlation that tightly connects the isotropic energy of the prompt GRB ( E γ ,iso ) with the end time of the X-ray plateau ( T a ) and the corresponding X-ray luminosity at the end time ( L X ) has been found. Here we show that there is a clear redshift evolution in the correlation. Furthermore, because the power-law indices of L X and E γ ,iso in the correlation function are almost identical, the L – T – E correlation is insensitive to cosmological parameters and cannot be used as a satisfactory standard candle. On the other hand, based on a sample including 121 long GRBs, we establish a new three-parameter correlation that connects L X , T a , and the spectral peak energy E p , i.e., the L – T – E p correlation. This correlation strongly supports the so-called Combo-relation established by Izzo et al. After correcting for the redshift evolution, we show that the de-evolved L – T – E p correlation can be used as a standard candle. By using this correlation alone, we are able to constrain the cosmological parameters as Ω m = 0.389 − 0.141 + 0.202 (1 σ ) for the flat ΛCDM model, or Ω m = 0.369 − 0.191 + 0.217 and w = − 0.966 − 0.678 + 0.513 (1 σ ) for the flat w CDM model. Combining with other cosmological probes, more accurate constraints on the cosmology models are presented.