First results on sub-GeV spin-dependent dark matter interactions with $$^{7}$$ 7 Li

Abstract In this work, we want to highlight the potential of lithium as a target for spin-dependent dark matter search in cryogenic experiments, with a special focus on the low-mass region of the parameter space. We operated a prototype detector module based on a $$\hbox {Li}_2\hbox {MoO}_4$$ Li2MoO4 target crystal in an above-ground laboratory. Despite the high background environment, the detector sets a competitive limit on spin-dependent interactions of dark matter particles with protons and neutrons for masses between $$0.8~\hbox {GeV/c}^2$$ 0.8GeV/c2 and $$1.5~\hbox {GeV/c}^2$$ 1.5GeV/c2 .