Surface roughness interpretation of 730 kg days CRESST-II results

TL;DR

This paper reinterprets the CRESST-II dark matter search results by proposing that surface roughness and ion sputtering effects can explain the observed excess events, challenging the dark matter signal attribution.

Contribution

It introduces a novel surface roughness model combined with ion sputtering effects to explain excess events in dark matter detection experiments.

Findings

Surface roughness significantly affects event interpretation.

Ion sputtering can mimic dark matter signals.

Revised background model reduces the excess attributed to dark matter.

Abstract

The analysis presented in the recent publication of the CRESST-II results finds a statistically significant excess of registered events over known background contributions in the acceptance region and attributes the excess to a possible Dark Matter signal, caused by scattering of relatively light WIMPs. We propose a mechanism which explains the excess events with ion sputtering caused by 206Pb recoils and alpha particles from 210Po decay, combined with realistic surface roughness effects.