The COSINUS project - a NaI-based cryogenic calorimeter for direct dark matter detection

Abstract

At present the results in the field of direct dark matter search are in tension: the positive claim of DAMA/LIBRA versus null results from other experiments. However, the comparison of the results of different experiments involves model dependencies, in particular because of the different target materials in use. The COSINUS R&D project aims to operate NaI as a cryogenic calorimeter. Such a detector would not only allow for a direct comparison to DAMA/LIBRA, but would also provide a low(er) nuclear recoil threshold and particle discrimination.

Rare event searches with cryogenic detectors

“…A few experiments attempt to cross-check DAMA/LIBRA results with NaI crystals, using a similar technology to test the annual modulation of a dark matter signal. The COSINUS experiment has taken on the challenge of adapting CRESST technology to NaI target crystals, aiming to scrutinize the observation made by the DAMA experiment regarding the annually modulated dark matter signal [19]. The distinct advantage of COSINUS, compared with the DAMA/LIBRA experiment, lies in its event-by-event signal versus background separation capabilities, setting it apart from other NaI-based detectors trying to test DAMA/LIBRA observations.…”

“…The scintillation light, measured by a LD and read out by a separate TES, allows an event-by-event particle discrimination. To achieve a sensitivity comparable with the DAMA/LIBRA experiment, an energy resolution for the NaI crystals of 0.2 keV is needed, corresponding to a nuclear recoil energy threshold of 1 keV [19]. The expected sensitivity of the COSINUS experiment compared with the parameter region preferred by DAMA, using standard dark matter astrophysical assumptions, is shown in figure 9 [20].…”