# Very-high-energy gamma-ray observations of the Type Ia Supernova SN 2014J with the MAGIC telescopes

## TL;DR

This study used MAGIC telescopes to search for very-high-energy gamma rays from the nearby Type Ia supernova SN 2014J, setting the first upper limits on such emissions and constraining models of gamma-ray production in supernovae.

## Contribution

First to establish upper limits on VHE gamma-ray emission from a Type Ia supernova, providing constraints on theoretical models of gamma-ray production in these explosions.

## Key findings

- No significant gamma-ray excess detected from SN 2014J.
- Upper limits on gamma-ray flux above 300 GeV and 700 GeV were established.
- The energy emitted in TeV gamma rays is less than 10^-6 of the supernova's total energy.

## Abstract

In this work we present data from observations with the MAGIC telescopes of SN 2014J detected in January 21 2014, the closest Type Ia supernova since Imaging Air Cherenkov Telescopes started to operate. We probe the possibility of very-high-energy (VHE; $E\geq100$ GeV) gamma rays produced in the early stages of Type Ia supernova explosions. We performed follow-up observations after this supernova explosion for 5 days, between January 27 and February 2 in 2014. We search for gamma-ray signal in the energy range between 100 GeV and several TeV from the location of SN 2014J using data from a total of $\sim5.5$ hours of observations. Prospects for observing gamma-rays of hadronic origin from SN 2014J in the near future are also being addressed. No significant excess was detected from the direction of SN 2014J. Upper limits at 95$\%$ confidence level on the integral flux, assuming a power-law spectrum, d$F/$d$E\propto E^{-\Gamma}$, with a spectral index of $\Gamma=2.6$, for energies higher than 300 GeV and 700 GeV, are established at $1.3\times10^{-12}$ and $4.1\times10^{-13}$ photons~cm$^{-2}$s$^{-1}$, respectively. For the first time, upper limits on the VHE emission of a Type Ia supernova are established. The energy fraction isotropically emitted into TeV gamma rays during the first $\sim10$ days after the supernova explosion for energies greater than 300 GeV is limited to $10^{-6}$ of the total available energy budget ($\sim 10^{51}$ erg). Within the assumed theoretical scenario, the MAGIC upper limits on the VHE emission suggest that SN 2014J will not be detectable in the future by any current or planned generation of Imaging Atmospheric Cherenkov Telescopes.