Diurnal modulation due to self-interacting mirror and hidden sector dark matter

TL;DR

This paper investigates how self-interacting mirror and hidden sector dark matter can cause daily variations in detection signals, with potential for significant diurnal modulation detectable in different hemispheres.

Contribution

It introduces the concept of diurnal modulation caused by self-interacting dark matter and estimates its size for detectors in various locations, highlighting the potential for detection.

Findings

Diurnal modulation peaks in April for northern hemisphere detectors.

Southern hemisphere detectors show larger diurnal variation.

Relocating CoGeNT to Argentina could enable a 5σ discovery in 30 days.

Abstract

Mirror and more generic hidden sector dark matter models can simultaneously explain the DAMA, CoGeNT and CRESST dark matter signals consistently with the null results of the other experiments. This type of dark matter can be captured by the Earth and shield detectors because it is self-interacting. This effect will lead to a diurnal modulation in dark matter detectors. We estimate the size of this effect for dark matter detectors in various locations. For a detector located in the northern hemisphere, this effect is expected to peak in April and can be detected for optimistic parameter choices. The diurnal variation is expected to be much larger for detectors located in the southern hemisphere. In particular, if the CoGeNT detector were moved to e.g. Sierra Grande, Argentina then a $5 \sigma$ dark matter discovery would be possible in around 30 days of operation.