Searching for dark matter with helium atom

TL;DR

This paper models the interaction between dark matter particles and helium atoms to estimate electronic excitation cross sections, providing data relevant for future dark matter detection experiments.

Contribution

It introduces a method using the boost operator and configuration interaction to estimate helium excitation cross sections caused by dark matter interactions.

Findings

Estimated upper limit of excitation cross section: 9.7×10⁻⁸ barns

Calculated total electronic excitation cross section for helium

Provides a basis for future scintillator-based dark matter detection experiments.

Abstract

With the help of the boost operator we can model the interaction between a weakly interacting particle(WIMP) of dark matter(DAMA) and an atomic nuclei. Via this "kick" we calculate the total electronic excitation cross section of the helium atom. The bound spectrum of He is calculated through a diagonalization process with a configuration interaction (CI) wavefunction built up from Slater orbitals. All together 19 singly- and doubly-excited atomic sates were taken with total angular momenta of L=0,1 and 2. Our calculation may give a rude estimation about the magnitude of the total excitation cross section which could be measured in later scintillator experiments. The upper limit of the excitation cross section is $9.7\cdot 10^{-8}$ barn.