Speaker
Description
The study of ($\alpha,n$) reactions is becoming increasingly important for the rare-event search community. Alpha particles originating from uranium and thorium decay chains can interact with detector materials, producing neutrons that may induce nuclear recoils in the region of interest for direct dark matter searches, thereby generating a background indistinguishable from a WIMP signal.
A reliable prediction of the resulting neutron yield requires precise knowledge of the relevant ($\alpha,n$) cross-sections. However, current calculations are affected by significant uncertainties. In particular, the ${}^{40}$Ar($\alpha,n$) cross-section has never been directly measured in the energy range relevant for WIMP searches.
In this talk, I will discuss the uncertainties associated with the calculation of neutron backgrounds in dark matter experiments, with particular emphasis on the impact of argon cross-section uncertainty on the neutron background evaluation for DarkSide-20k. Finally, I will present the work in progress towards a direct measurement of the ${}^{40}$Ar($\alpha,n$) cross-section by a newly formed Spanish collaboration.
| Main Contribution topic | Direct detection |
|---|---|
| Secondary contribution topic | Instrumentation for Dark Matter |