# Gamma-ray line measurements from supernova explosions

## TL;DR

This paper reviews gamma-ray line emissions from supernovae, discussing observations of radioactive decay isotopes like 56Ni and 44Ti, and what these emissions reveal about supernova explosion mechanisms and properties.

## Contribution

It provides a comprehensive analysis of gamma-ray line measurements from supernovae, highlighting recent observational data and their implications for understanding supernova physics.

## Key findings

- Detected gamma-ray lines from 56Ni and 44Ti in supernova remnants
- Observed gamma-ray emissions from Cas A, SN1987A, and SN2014J
- Discussed the potential of gamma-ray spectroscopy to reveal supernova explosion details

## Abstract

Gamma ray lines are expected to be emitted as part of the afterglow of supernova explosions, because radioactive decay of freshly synthesised nuclei occurs. Significant radioactive gamma ray line emission is expected from 56Ni and 44Ti decay on time scales of the initial explosion (56Ni, tau~days) and the young supernova remnant (44Ti,tau~90 years). Less specific, and rather informative for the supernova population as a whole, are lessons from longer lived isotopes such as 26Al and 60Fe. From isotopes of elements heavier than iron group elements, any interesting gamma-ray line emission is too faint to be observable. Measurements with space-based gamma-ray telescopes have obtained interesting gamma ray line emissions from two core collapse events, Cas A and SN1987A, and one thermonuclear event, SN2014J. We discuss INTEGRAL data from all above isotopes, including all line and continuum signatures from these two objects, and the surveys for more supernovae, that have been performed by gamma ray spectrometry. Our objective here is to illustrate what can be learned from gamma-ray line emission properties about the explosions and their astrophysics.