Calculated WIMP signals at the ANDES laboratory: comparison with northern and southern located dark matter detectors

TL;DR

This study predicts how diurnal and annual WIMP detection signals vary with laboratory location, highlighting amplified diurnal modulation at the southern hemisphere site of ANDES compared to northern detectors.

Contribution

It provides the first analysis of diurnal and annual WIMP signal modulation dependence on laboratory geographic coordinates, specifically for the planned ANDES underground facility.

Findings

Diurnal modulation signals are amplified at the ANDES site.

Annual modulation signals are unaffected by geographic location.

Predictions for NaI and Ge detectors at ANDES are consistent with existing northern detectors.

Abstract

Weakly Interacting Massive Particles (WIMP) are possible components of the Universe's Dark Matter. The detection of WIMP is signalled by the recoil of the atomic nuclei which form a detector. CoGeNT at the Soudan Underground Laboratory (SUL) and DAMA at the Laboratori Nazionali del Gran Sasso (LNGS) have reported data on annual modulation of signals attributed to WIMP. Both experiments are located in laboratories of the northern hemisphere. Dark matter detectors are planned to operate (or already operate) in laboratories of the southern hemisphere, like SABRE at Stawell Underground Physics Laboratory (SUPL) in Australia, and DM-ICE in the South Pole. In this work we have analysed the dependence of diurnal and annual modulation of signals, pertaining to the detection of WIMP, on the coordinates of the laboratory, for experiments which may be performed in the planned new underground facility ANDES (Agua Negra Deep Experimental Site), to be built in San Juan, Argentina. We made predictions for NaI and Ge-type detectors placed in ANDES, to compare with DAMA, CoGeNT, SABRE and DM-ICE arrays, and found that the diurnal modulation of the signals, at the site of ANDES, is amplified at its maximum value, both for NaI (Ge)-type detectors, while the annual modulation remains unaffected by the change in coordinates from north to south.