Multiwavelength analysis of three SNe associated with GRBs observed by GROND

TL;DR

This study analyzes three GRB-associated supernovae using multiwavelength data, estimating their physical properties and confirming they are generally brighter than typical type-Ic supernovae without GRBs.

Contribution

It provides detailed multiwavelength analysis and physical parameter estimation of three GRB-SNe, expanding understanding of their luminosity and explosion characteristics.

Findings

SN 2010ma is highly luminous with 1.4x10^43 erg/s.

SNe 2008hw and 2009nz have peak luminosities similar to SN 1998bw.

All three SNe have nickel masses around 0.4-0.5 Msun.

Abstract

After the discovery of the first connection between GRBs and SNe almost two decades ago, tens of SN-like rebrightenings have been discovered and about seven solid associations have been spectroscopically confirmed to date. Using GROND optical/NIR data and Swift X-ray/UV data, we estimate the intrinsic extinction, luminosity, and evolution of three SN rebrightenings in GRB afterglow light curves at z~0.5. The SNe 2008hw, 2009nz, and 2010ma exhibit 0.80, 1.15, and 1.78 times the optical (r band) luminosity of SN 1998bw, respectively. While SN 2009nz evolves similarly to SN 1998bw, SNe 2008hw and 2010ma show earlier peak times. The quasi-bolometric light curves were corrected for the contribution of the NIR bands using data available in the literature and blackbody fits. The large luminosity of SN 2010ma (1.4x10^43 erg/s) is confirmed, while SNe 2008hw and 2009nz reached a peak luminosity closer to SN 1998bw. Physical parameters of the SN explosions, such as synthesised nickel mass, ejecta mass, and kinetic energy, are estimated using Arnett's analytic approach, which resulted in nickel masses of around 0.4-0.5 Msun. By means of the a very comprehensive data set, we found that the luminosity and the nickel mass of SNe 2008hw, 2009nz, and 2010ma resembles those of other known GRB-associated SNe. This findings strengthens previous claims of GRB-SNe being brighter than type-Ic SNe unaccompanied by GRBs.