Prospects For Identifying Dark Matter With CoGeNT

TL;DR

This paper projects that one year of CoGeNT data, especially with an upgrade, can confirm if the observed excess is due to dark matter by detecting annual modulation and analyzing its spectrum.

Contribution

It provides projections for CoGeNT's future data collection and upgrade capabilities to confirm dark matter detection through annual modulation analysis.

Findings

One year of data could reveal a 2-3σ annual modulation.

The upgrade can measure the modulation energy spectrum.

Data will better constrain dark matter parameter space.

Abstract

It has previously been shown that the excess of events reported by the CoGeNT collaboration could be generated by elastically scattering dark matter particles with a mass of approximately 5-15 GeV. This mass range is very similar to that required to generate the annual modulation observed by DAMA/LIBRA and the gamma rays from the region surrounding the Galactic Center identified within the data of the Fermi Gamma Ray Space Telescope. To confidently conclude that CoGeNT's excess is the result of dark matter, however, further data will likely be needed. In this paper, we make projections for the first full year of CoGeNT data, and for its planned upgrade. Not only will this body of data more accurately constrain the spectrum of nuclear recoil events, and corresponding dark matter parameter space, but will also make it possible to identify seasonal variations in the rate. In particular, if the CoGeNT excess is the product of dark matter, then one year of CoGeNT data will likely reveal an annual modulation with a significance of 2-3$\sigma$. The planned CoGeNT upgrade will not only detect such an annual modulation with high significance, but will be capable of measuring the energy spectrum of the modulation amplitude. These measurements will be essential to irrefutably confirming a dark matter origin of these events.