# Detecting the imprint of a kilonova or supernova \\ in short GRB afterglows

## TL;DR

This paper investigates the conditions under which kilonovae and supernovae can be detected in short GRB afterglows, aiding in understanding their diversity and observational signatures.

## Contribution

It provides a model-based analysis of the detectability conditions for kilonovae and supernovae in short GRB afterglows, highlighting key parameters influencing their observability.

## Key findings

- Identified parameter spaces where kilonovae or supernovae outshine afterglows.
- Developed diagrams mapping burst energy and external density for detection likelihood.
- Provided peak luminosity and timing estimates for kilonovae based on physical parameters.

## Abstract

Short gamma-ray bursts result from mergers of two neutron stars or from collapsars, but probably at a smaller rate. In the first case, a kilonova occurs while in the second case a Type Ic supernova is expected. } {Even if future observations of kilonovae in association with gravitational wave events provide better data, detecting a kilonova during an afterglow follow-up would remain useful for exploring the diversity of the kilonova phenomenon. As supernovae produce a weaker gravitational signal, afterglow follow-up will be the only possible method to find one. In this work, we identify the conditions of the burst energy, external density, kilonova mass, supernova luminosity, that are necessary for the detection of a kilonova or supernova in the follow-up of short GRB afterglows.} {We have used a simple kilonova model to obtain the peak luminosities and times as a function of mass, expansion velocity and ejected matter opacity. Afterglow light curves are computed for a uniform medium and a stellar wind, in the kilonova and supernova cases, respectively.} {We represent, using diagrams of the burst kinetic energy vs. density of the external medium, the domains where the kilonova or supernova at maximum is brighter than the afterglow. %\LEt{Please check I have retained your intended meaning -> It's OK