Low background techniques on particle detectors for rare event searches
The nature of the Dark Matter (DM) is one of major open questions in modern physics with two interesting candidates: axions and Weakly Interacting Massive Particles (WIMPs). Axions arise from extensions of the Standard Model (SM) implementing the Peccei-Quinn mechanism. On the other hand, WIMPs appear in well-motivated extensions of the SM, like supersymmetry. Axions and WIMPs could have been produced in an early stage of the Universe and have been extensively searched during last decades.
The use of Micromegas (MICROMesh GAs Structure) readouts has been recently introduced for axion and WIMPs searches and proposed for different experiments: TREX-DM and IAXO. TREX-DM is located in the Canfranc Underground Laboratory and is looking for low-mass WIMPs, in a mass range that is attracting the interest of the experiments. On the other hand, IAXO is a proposed new generation solar axion helioscope with enhanced sensitivity. The low counting rates expected in these experiments require to bring down the experimental background to the lowest levels possible. Another important aspect to enhance the physics potential is to reduce the low energy threshold, that would increase TREX-DM sensitivity to even lower WIMP masses. Moreover, it would make IAXO sensitive to axion-electron coupling values.
The goal of this proposal is to reduce the background levels in order to reach sensitivity scenarios with discovery potential for axions and low-mass WIMPs and secondarily to reduce the low energy threshold. These objectives can be achieved by the use of some innovative aspects like the introduction of new Micromegas architectures and the use of new radiopure electronics. If the objectives are fulfilled, the advancements in the field would be tremendous, it will set the baseline for the design and construction of ultra-low background detectors for many different applications. Moreover, these new developments could be extrapolated to different kind of particle detectors.