Neutral-current neutrino cross section and expected supernova signals for $^{40}$Ar from a three-fold increase in the magnetic dipole strength

TL;DR

This paper investigates the neutral-current neutrino cross section for $^{40}$Ar at supernova energies, revealing a significant increase in magnetic dipole strength that impacts expected supernova detection signals in liquid argon detectors.

Contribution

It provides new experimental data on magnetic dipole strength in $^{40}$Ar and calculates the resulting neutrino cross sections using shell-model methods, informing supernova neutrino detection.

Findings

Three-fold increase in magnetic dipole strength at ~10 MeV in $^{40}$Ar

Revised calculations of neutrino cross sections at supernova energies

Implications for supernova neutrino detection in liquid argon detectors

Abstract

In view of the great interest in liquid argon neutrino detectors, the $^{40}$Ar($\gamma,\gamma'$)$^{40}$Ar$^{*}$ reaction was revisited to guide a calculation of the neutral current neutrino cross section at supernova energies. Using the nuclear resonance fluorescence technique with a monoenergetic, 99% linearly polarized photon beam, we report a three-fold increase in magnetic dipole strength at around 10 MeV in $^{40}$Ar. Based on shell-model calculations, and using the experimentally identified transitions, the neutral current neutrino cross sections for low-energy reactions on $^{40}$Ar are calculated.