Superfluid Effective Field Theory for Dark Matter Direct Detection

TL;DR

This paper develops an effective field theory for superfluid helium-4 to model quasiparticle interactions, providing a framework that can be applied to dark matter detection experiments involving superfluid helium.

Contribution

It introduces a novel EFT framework for superfluid helium-4 that combines symmetry principles with classical fluid dynamics, enabling detailed modeling of quasiparticle interactions.

Findings

Derived decay and scattering rates for quasiparticles and helium atoms.

Established a theoretical basis for understanding thermalization in superfluid helium.

Applied the EFT framework to potential dark matter detection scenarios.

Abstract

We develop an effective field theory (EFT) framework for superfluid ${}^4$He to model the interactions among quasiparticles, helium atoms and probe particles. Our effective field theory approach brings together symmetry arguments and power-counting and matches to classical fluid dynamics. We then present the decay and scattering rates for the relevant processes involving quasiparticles and helium atoms. The presented EFT framework and results can be used to understand the dynamics of thermalization in the superfluid, and can be further applied to sub-GeV dark matter direct detection with superfluid ${}^4$He.