# The activation method for cross section measurements in nuclear astrophysics

## TL;DR

This paper reviews the activation method in nuclear astrophysics for measuring reaction cross sections, highlighting techniques, advantages, and applications including Accelerator Mass Spectrometry, to improve understanding of stellar reaction rates.

## Contribution

It provides a comprehensive review of the activation method and related techniques for cross section measurements in nuclear astrophysics, emphasizing recent developments and applications.

## Key findings

- Activation method offers advantages over in-beam detection.
- Various techniques for measuring produced isotopes are detailed.
- Accelerator Mass Spectrometry is a valuable tool in this context.

## Abstract

The primary aim of experimental nuclear astrophysics is to determine the rates of nuclear reactions taking place in stars in various astrophysical conditions. These reaction rates are important ingredient for understanding the elemental abundance distribution in our solar system and the galaxy. The reaction rates are determined from the cross sections which need to be measured at energies as close to the astrophysically relevant ones as possible. In many cases the final nucleus of an astrophysically important reaction is radioactive which allows the cross section to be determined based on the off-line measurement of the number of produced isotopes. In general, this technique is referred to as the activation method, which often has substantial advantages over in-beam particle- or gamma-detection measurements. In this paper the activation method is reviewed from the viewpoint of nuclear astrophysics. Important aspects of the activation method are given through several reaction studies for charged particle, neutron and gamma-induced reactions. Various techniques for the measurement of the produced activity are detailed. As a special case of activation, the technique of Accelerator Mass Spectrometry in cross section measurements is also reviewed.