Speaker
Description
The discrimination of nuclear recoils (NR) possibly induced by dark matter (DM) particles from the electronic recoils (ER) induced by the ordinary matter particles is one of the main experimental challenges of direct DM searches in the ${\rm GeV}/c^2$ mass region. Gaseous Time Projection Chambers (TPCs) with optical readout are a promising and innovative technique: the high granularity of the newest sCMOS light sensors, with the help of additional fast photosensors, allow high precision 3D position reconstruction with a good energy resolution and a sub-keV low energy threshold.
The Cygno collaboration is developing a gaseous TPC with optical readout filled with an atmospheric pressure He:CF$_4$ gas mixture, with a triple Gas Electron Multiplier (GEM) amplification stage. As a result, low energy events result in visible tracks, which are acquired by means of the sCMOS camera and the fast photosensors.
In this contribution, we present the main feature of the Cygno project, with particular focus on the current R&D activities and the future perspectives and goals. LIME, the largest 50 L prototype built so far, has been recently moved underground at the Laboratori Nazionali del Gran Sasso (LNGS) to evaluate the performances of this experimental approach in a low radioactive background environment. This campaign has the goal of proving the scalability of the Cygno detector approach to a bigger O(30 -100 ${\rm m}^3$) apparatus that could contribute to directional DM and neutrino searches.
