Multi-wavelength analysis of short GRB 201221D and its comparison with other high \& low redshift short GRBs

TL;DR

This paper analyzes the properties of short GRB 201221D at high redshift, compares it with other SGRBs, and discusses implications for their progenitors, highlighting differences in spectral features and host galaxy characteristics.

Contribution

It provides a detailed multi-wavelength analysis of a high-redshift short GRB and compares its properties with other SGRBs, exploring potential progenitor origins.

Findings

GRB 201221D has a softer peak energy compared to typical SGRBs.

Some high-redshift SGRBs share properties with long GRBs, suggesting possible collapsar origins.

Host galaxy analysis indicates diverse environments for SGRBs.

Abstract

We present a detailed analysis of short GRB 201221D lying at redshift $z= 1.045$. We analyse the high-energy data of the burst and compare it with the sample of short gamma-ray bursts (SGRBs). The prompt emission characteristics are typical of those seen in the case of other SGRBs except for the peak energy ($E_{\rm p}$), which lies at the softer end (generally observed in the case of long bursts). We estimate the host galaxy properties by utilising the {\sc Python}-based software {\sc Prospector} to fit the spectral energy distribution of the host. The burst lies at a high redshift relative to the SGRB sample with a median redshift of $z=0.47$. We compare the burst characteristics with other SGRBs with known redshifts along with GRB 200826A (SGRB originated from a collapsar). A careful examination of the characteristics of SGRBs at different redshifts reveals that some of the SGRBs lying at high redshifts have properties similar to long GRBs indicating they might have originated from collapsars. Further study of these GRBs can help to explore the broad picture of progenitor systems of SGRBs.