On the extraction of weak transition strengths via the (3He,t) reaction at 420 MeV

TL;DR

This study measures weak nuclear transition strengths using the (3He,t) reaction at 420 MeV across various targets, revealing simple mass-dependent trends that aid in determining Gamow-Teller distributions where beta-decay calibration is unavailable.

Contribution

It demonstrates that (3He,t) reaction cross sections follow predictable trends with mass number, enabling more accurate extraction of weak transition strengths in diverse nuclei.

Findings

Proportionalities between strengths and cross sections follow simple mass-dependent trends.

Distorted-wave Born approximation calculations overestimate data but help interpret experimental features.

Trends can be used to determine Gamow-Teller strengths without beta-decay calibration.

Abstract

Differential cross sections for transitions of known weak strength were measured with the (3He,t) reaction at 420 MeV on targets of 12C, 13C, 18O, 26Mg, 58Ni, 60Ni, 90Zr, 118Sn, 120Sn and 208Pb. Using this data, it is shown the proportionalities between strengths and cross sections for this probe follow simple trends as a function of mass number. These trends can be used to confidently determine Gamow-Teller strength distributions in nuclei for which the proportionality cannot be calibrated via beta-decay strengths. Although theoretical calculations in distorted-wave Born approximation overestimate the data, they allow one to understand the main experimental features and to predict deviations from the simple trends observed in some of the transitions.