Ponente
Descripción
CYGNO, a directional Dark Matter TPC optically readout
We are going to discuss the latest R&D progress concerning the enhancement of the light yield in the CYGNO experiment. CYGNO is a directional detector for low mass (0.5-50 GeV) Dark Matter WIMP searches. The experiment is focused on developing a high-precision and optically readout gaseous Time Projection Chamber and, given its directional capabilities, CYGNO is also expected to be able to perform solar neutrino spectroscopy.
In the CYGNO approach, the ionization charge is amplified by three Gas Electron Multipliers (GEMs) operating in a He:CF$_4$ mixture, a gas sensible to both spin-dependent and independent interactions. The readout system comprises scientific CMOS cameras and PMTs that read the visible light emitted during the charge amplification process. Their combined analysis allows a three-dimensional and topological reconstruction of the particle interactions in the gas.
We will discuss the state-of-the-art results of LIME, a 50 cm prototype that was installed and commissioned in the underground laboratories of LNGS in February 2022. LIME results will help validate the design of a 0.4 m$^3$ detector which will ultimately serve as a demonstrator of the technology, performance, and scalability of the project for the experiment's phase 1 detector, a $O(30)$ m$^3$ TPC already competitive with other DM search experiments in the low WIMP mass region.
Achieving a higher light yield would further improve CYGNO's sensitivity to lower-mass WIMPs. With this in mind, within the CYGNO R&D framework, an ITO thin glass window was introduced in our 0.5L prototype, MANGO, resulting in the introduction of an induction field where the secondary electrons are further accelerated to the point where additional scintillation is possible, and with little additional charge production. This feature was further tested using different GEM thicknesses and configurations, and a Maxwell simulation was created to study the electric fields in the regions around the GEM. Such simulation helped us in the interpretation of our results on detector energy and spatial resolutions. The cross-interpretation of experimental data acquired in these conditions and simulations will be discussed.
David J. G. Marques* on behalf of the CYGNO collaboration
*Gran Sasso Science Institute, 67100 L’Aquila, Italy
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso, 67100 Assergi, Italy
Mailing Address: david.marques@gssi.it
