Evidence for gravitational lensing of GRB 200716C

Abstract

Observationally, there is a small fraction of Gamma-ray bursts (GRBs) with prompt emission observed by Fermi/GBM that are composed of two pulses. Occasionally, the distance to a GRB may be lensed when a high mass astrophysical object resides in the path between the GRB source and observer. In this paper, we describe GRB 200716C, which has a two-pulse emission and duration of a few seconds. We present a Bayesian analysis identifying gravitational lensing in both temporal and spectral properties, and calculate the time delay ($\Delta t\sim 1.92$ s) and magnification ($\gamma \sim 1.5$) between those two pulses based on the temporal fits. One can roughly estimate the lens mass to be about $2.4\times 10^5{M}_{\odot }$ in the rest frame. We also calculate the false alarm probability for this detection to be about 0.07\% with trial factors, and a present-day number density of about $808\mathrm{Mp}{\mathrm{c}}^{-3}$ with an energy density $\Omega \sim 1.4\times 10^{-3}$. If the first pulse of this GRB near the trigger time is indeed gravitationally echoed by a second pulse, GRB 200716C may be a short GRB candidate with extended emission.

22 pages, 2 tables, 7 figures, ApJL in press, added two references

References in corpus (21)

• Discovery of the peculiar supernova 1998bw in the error box of GRB980425
• Methods and results of an automatic analysis of a complete sample of Swift-XRT observations of GRBs
• The Fermi Gamma-Ray Burst Monitor
• The Physics of Gamma-Ray Bursts and Relativistic Jets
• A Photometric Redshift of z ~ 9.4 for GRB 090429B
• Strong Lensing by Galaxies
• An introduction to Bayesian inference in gravitational-wave astronomy: parameter estimation, model selection, and hierarchical models
• A Comprehensive Analysis of Fermi Gamma-Ray Burst Data. I. Spectral Components and Their Possible Physical Origins of LAT/GBM GRBs
• Galaxies at the extremes: Ultra-diffuse galaxies in the Virgo Cluster
• The First Swift BAT Gamma-Ray Burst Catalog
• Synchrotron Origin of the Typical GRB Band Function - A Case Study of GRB 130606B
• Precursor activity in bright long BATSE gamma-Ray Bursts
• Precursors in Swift Gamma Ray Bursts with redshift
• Evidence for an intermediate-mass black hole from a gravitationally lensed gamma-ray burst
• Internal Energy Dissipation of Gamma-Ray Bursts Observed with Swift: Precursors, Prompt Gamma-rays, Extended emission and Late X-ray Flares
• Curvature Effect of a Non-Power-Law Spectrum and Spectral Evolution of GRB X-Ray Tails
• How to switch on and off a Gamma-ray burst through a magnetar
• Extremely bright GRB 160625B with multi-episodes emission: Evidences for long-term ejecta evolution
• GRB 200716C: Evidence for a Short Burst Being Lensed
• Characteristics of Two-episode Emission Patterns in {\em Fermi} Long Gamma-Ray Bursts
• Evidence for gravitational-wave dominated emission in the central engine of short GRB 200219A

Cited by in corpus (4)

• Gravitational lensing in the presence of plasma scattering with application to Fast Radio Bursts
• Gravitationally Lensed Orphan Afterglows of Gamma-Ray Bursts
• Fermi-GBM Observation of GRB 090717034: ${\chi }^2$ Test Confirms Evidence of Gravitational Lensing by a Supermassive Black Hole with Million Solar Mass
• Multi-scale VLBI observations of the candidate host galaxy of GRB 200716C