Impact of $^7$Be breakup on $^7$Li(p,n) Neutron Spectrum

TL;DR

This study investigates how the breakup of $^7$Be influences the neutron spectrum in the $^7$Li(p,n) reaction, combining experimental measurements with theoretical calculations to understand continuum neutron production.

Contribution

It provides a detailed analysis of $^7$Be breakup effects on neutron spectra using combined experimental data and CDCC-CRC modeling at 21 MeV proton energy.

Findings

Breakup levels of $^7$Be significantly affect neutron spectra.

Theoretical calculations successfully reproduce experimental data.

Model parameters can be adapted to different proton energies.

Abstract

The formation of continuum neutron distribution in $^7$Li(p,n) has been identified as due to the coupling of the $^7$Be breakup levels to the final state of the reaction. The continuum neutron spectra produced by $^7$Li(p,n) reaction has been estimated by measuring the double differential cross sections for continuum and resonant breakup of $^7$Be, through $^7$Li(p,n)$^7$Be$^*$ reaction at 21 MeV of proton energy. The breakup contributions from continuum and $5/2^-$, $7/2^-$ states of $^7$Be have been identified. The measured double differential cross sections have been reproduced through CDCC-CRC calculations. The cross sections were projected to neutron spectrum using Monte-Carlo approach and validated using experimentally measured $^3$He gated neutron spectra. $^7$Li(p,n) neutron spectrum at 20 MeV incident proton energy measured by McNaughton. et al. has been reproduced by adapting estimated model parameters for the reaction.