Speaker
Description
The QuIPS (Quantum Invisible Particle Sensor) experiment reconstructs the full kinematics of weak nuclear decays using a radioisotope-loaded silica nanosphere, optically trapped in ultra-high vacuum and surrounded by active particle detectors. The recoil impulse imparted to the sphere, read out with quantum-limited sensitivity, is combined with a direct measurement of the emitted beta particle to infer the neutrino momentum. This enables searches for heavy sterile neutrinos in the keV to few MeV range, as well as other BSM physics. I will give an overview of the project, including the beta detector we have built at LBL. It uses two planes of ultra-thin CMOS sensors backed by a plastic scintillator for vertexing and momentum reconstruction, in a compact package designed to operate at 10⁻⁸ mbar. I will present its first calibration results and its integration with the optical trap at Yale, where the first recoil demonstration using F-18 loaded spheres is underway. I will also show initial designs for a 1550 nm optical levitation setup under development at LBL and outline the path to future searches, including sphere arrays, squeezed mechanical states of the sphere's motion, and improved beta detection.