Speaker
Description
The CYGNO collaboration aims to propose a large volume (O(30m^3)) gaseous Time Projection Chamber (TPC) with optical readout to search for rare events, such as interactions of DM in the GeV mass range and solar neutrinos. The TPC, operated with a He:CF4 gas mixture at atmospheric pressure, uses a triple Gas Electron Multiplier (GEM) stack to amplify primary ionization charges and produce light. A low-noise sCMOS camera and fast light sensors detect the light, allowing a full 3D-reconstruction of the tracks with good energy resolution and high sensitivity in the few keV energy range. This detailed reconstruction of the event topology provides a powerful tool to discriminate DM signal nuclear recoils from background electronic recoils. A 50 liter prototype, the Long Imaging ModulE (LIME), was built to conclude the R&D phase of the CYGNO project. It is currently being commissioned underground at Laboratori Nazionali del Gran Sasso. We present preliminary estimates of the environmental and internal background and assessments of detector performance, whose characterization is essential to pursue CYGNO's approach. We also present the results of the overground campaign at Laboratori Nazionali di Frascati (LNF) in terms of energy response, track reconstruction, and event identification, which were carried out by means of radioactive sources. These results are used to evaluate the sensitivity of the CYGNO proposal in searching for DM in the GeV mass range.
