Measurement of ${}^{nat}$Pb($\nu_e$,X$n$) production with a stopped-pion neutrino source

TL;DR

This study measures the neutrino-induced neutron production on lead using a stopped-pion source at SNS, providing the first inelastic neutrino-nucleus process measurement by COHERENT, with results consistent with theoretical predictions within uncertainties.

Contribution

First measurement of the Pb(nu_e, Xn) process with a stopped-pion neutrino source by COHERENT, combining new and previous data for cross section analysis.

Findings

Measured cross section is 0.29 (+0.17/-0.16) times the MARLEY prediction.

Results are consistent with no neutrino-induced neutron events at 1.8 sigma.

First inelastic neutrino-nucleus process studied by COHERENT.

Abstract

Using neutrinos produced at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL), the COHERENT collaboration has studied the Pb($\nu_e$,X$n$) process with a lead neutrino-induced-neutron (NIN) detector. Data from this detector are fit jointly with previously collected COHERENT data on this process. A combined analysis of the two datasets yields a cross section that is $0.29^{+0.17}_{-0.16}$ times that predicted by the MARLEY event generator using experimentally-measured Gamow-Teller strength distributions, consistent with no NIN events at 1.8$\sigma$. This is the first inelastic neutrino-nucleus process COHERENT has studied, among several planned exploiting the high flux of low-energy neutrinos produced at the SNS.