Progress on Superconducting Bolometers for the RICOCHET Experiment

The RICOCHET experiment located at the research reactor at ILL in Grenoble, France is a Coherent Elastic Neutrino-Nucleus Scattering (CEνNS) observatory that aims to detect reactor neutrinos through low-energy nuclear recoils. Consisting of cryogenic bolometers with heat and charge readouts, the experiment has been installed and operated at ILL since the first half of 2024 with a small array of Ge detectors, as a precursor of the full-sized CryoCube detector. The complementary detector array under active R&D, Q-Array, uses superconducting centimeter-scale crystals (Zn, Al, and Sn) of around ∼50 grams as the recoil target and Manganese-doped Al Transition-Edge-Sensors (TESes) for readout. We present the Q-Array as the focus of this work and discuss the Al and Sn data along with their implications for two key goals: (1) O(50 eV) nuclear recoil threshold and (2) Particle identification (PID) for nuclear and electron recoil events.