Discriminating WIMP-nucleus response functions in present and future XENON-like direct detection experiments

Understand

The standard interpretation of direct-detection limits on dark matter involves particular assumptions of the underlying WIMP-nucleus interaction, such as, in the simplest case, the choice of a Helm form factor that phenomenologically describes an isoscalar spin-independent interaction.

• In general, the interaction of dark matter with the target nuclei may well proceed via different mechanisms, which would lead to a different shape of the corresponding nuclear structure factors as a function of the momentum transfer $q$.
• We study to what extent different WIMP-nucleus responses can be differentiated based on the $q$-dependence of their structure factors (or "form factors").
• We assume an overall strength of the interaction consistent with present spin-independent limits and consider an exposure corresponding to XENON1T-like, XENONnT-like, and DARWIN-like direct detection experiments.