SPI Measurements of Nucleosynthesis Gamma-Rays

TL;DR

This paper reviews gamma-ray line measurements from radioactive isotopes like 26Al and 60Fe to study nucleosynthesis in massive stars and supernovae, highlighting recent observational results and their astrophysical significance.

Contribution

It summarizes recent multi-year gamma-ray observations of nucleosynthesis isotopes and discusses their implications for stellar structure and galactic processes.

Findings

Detection of gamma-ray lines from 26Al and 60Fe in various regions

Isotopic ratios provide insights into stellar nucleosynthesis

Doppler shifts reveal kinematic information of source regions

Abstract

Studies based on the gamma-ray lines from radioactive decay of unstable isotopes produced in massive-star and supernova nucleosynthesis have been among INTEGRAL's prominent science achievements. 26Al has become a tool to study specific source regions, such as massive-star groups and associations in nearby regions which can be discriminated from the galactic-plane background, and the inner Galaxy where Doppler shifted lines add to the astronomical information. 60Fe is co-produced by the sources of 26Al, and the isotopic ratio from their nucleosynthesis encodes stellar-structure information. Here we summarize latest results using the accumulated multi-year database of observations, point to the relevant publications, and discuss their astrophysical implications.