Measuring cosmological parameters with a luminosity-time correlation of gamma-ray bursts

Gamma-ray bursts (GRBs), as a possible probe to extend the Hubble diagram to high redshifts, have attracted much attention recently. In this paper, we select two samples of GRBs that have a plateau phase in X-ray afterglow. One is short GRBs (SGRBs) with plateau phases dominated by magnetic dipole (MD) radiations. The other is long GRBs (LGRBs) with gravitational wave (GW) dominated plateau phases. These GRBs can be well standardized using the correlation between the plateau luminosity L-0 and the end time of plateau t(b). The so-called circularity problem is mitigated by using the observational Hubble parameter data and Gaussian process method. The calibrated L-0 - t(b) correlations are also used to constrain Lambda cold dark matter (Lambda CDM) and w(z) = w(0) models. Combining the MD-LGRBs sample from Wang et al. (2021) and the MD-SGRBs sample, we find Omega(m) = 0.33(-0.09)(+0.06) and Omega(Lambda) = 1.06(-0.34)(+0.15) excluding systematic uncertainties in the non-flat Lambda CDM model. Adding Type Ia supernovae from Pantheon sample, the best-fitting results are w(0) =-1.11(-0.15)(+0.11) and Omega(m) = 0.34(-0.04)(+0.05) in the w = w(0) model. These results are in agreement with the Lambda CDM model. Our result supports that selection of GRBs from the same physical mechanism is crucial for cosmological purposes.

Automated summary

This paper investigates gamma-ray bursts (GRBs) with plateau phases in X-ray afterglow and finds that selecting GRBs from the same physical mechanism is crucial for cosmological purposes. The study calibrates the correlations between plateau luminosity and end time of plateau to constrain ΛCDM and w(z) = w(0) models. The results support the ΛCDM model and highlight the importance of careful selection of GRBs for cosmological studies.