Absorption of Fermionic Dark Matter in the PICO-60 C${}_3$F${}_8$ Bubble Chamber

Abstract

Fermionic dark matter absorption on nuclear targets via neutral current interactions is explored using a non-relativistic effective field theory framework. An analysis of data from the PICO-60 C${}_3$F${}_8$ bubble chamber sets leading constraints on spin-independent absorption for dark matter masses below 23 MeV/${\text{c}}^2$ and establishes the first limits on spin-dependent absorptive interactions. These results demonstrate the sensitivity of bubble chambers to low-mass dark matter and underscore the importance of absorption searches in expanding the parameter space of direct detection experiments.