Search for strong gravitational lensing effect in the current GRB data of BATSE

TL;DR

This study investigates the potential gravitational lensing effects on gamma-ray bursts (GRBs) caused by dark matter halos in galaxies, analyzing BATSE data to find lensed pairs but ultimately not detecting any.

Contribution

It models GRB lensing probabilities assuming dark matter halos follow a singular isothermal sphere profile and applies this to analyze BATSE data for lensing signatures.

Findings

No convincing lensed GRB pairs found in BATSE data

Calculated lensing probabilities based on dark matter halo models

Discussed implications and future prospects for GRB lensing observations

Abstract

Because gamma-ray bursts (GRBs) trace the high-z Universe, there is an appreciable probability for a GRB to be gravitational lensed by galaxies in the universe. Herein we consider the gravitational lensing effect of GRBs contributed by the dark matter halos in galaxies. Assuming that all halos have the singular isothermal sphere (SIS) mass profile in the mass range $10^{10} h^{-1} M_\odot < M < 2\times 10^{13} h^{-1}M_\odot $ and all GRB samples follow the intrinsic redshift distribution and luminosity function derived from the Swift LGRBs sample, we calculated the gravitational lensing probability in BATSE, Swift/BAT and Fermi/GBM GRBs, respectively. With an derived probability result in BATSE GRBs, we searched for lensed GRB pairs in the BATSE 5B GRB Spectral catalog. The search did not find any convincing gravitationally lensed events. We discuss our result and future observations for GRB lensing observation.