Speaker
Description
Coherent elastic neutrino–nucleus scattering (CE$\nu$NS) provides a powerful probe of the weak interaction, neutron distributions in nuclei, and new physics scenarios such as non-standard neutrino interactions, light mediators, and electromagnetic properties of neutrinos. We report results from the Mitchell Institute Neutrino Experiment at Reactor (MINER), which deployed cryogenic sapphire ($\mathrm{Al_2O_3}$) detectors equipped with phonon sensors, called Transition Edge sensors (TES), operating at mK temperature at the 1 $\mathrm{MW_{th}}$ TRIGA reactor at Texas A$\&$M University. The primary 72 g detector achieved a baseline energy resolution of about 40 eV, making it well suited for low-energy recoil measurements. Based on 158 g·days of reactor-on and 381 g·days of reactor-off data, no significant CE$\nu$NS excess was observed: the measured rate is dominated by reactor-induced backgrounds, with a best-fit signal strength relative to the Standard Model of $\mathrm{\rho=0.26\pm1534.74~(stat)\pm0.05~(sys)}$. This highlights the challenges of operating at low recoil energies near a research reactor.
To overcome these limitations, MINER will be relocated to the 85 $\mathrm{MW_{th}}$ High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory in 2025. The combination of $\mathrm{\sim70\times}$ higher antineutrino flux, improved compact shielding, and increased detector mass (multi-crystal sapphire tower) will enable CE$\nu$NS detection with 3$\sigma$ significance in $\sim$30 kg·days exposure, and potentially 5$\sigma$ with optimized background suppression. The upgraded setup is expected to deliver the first precision reactor-based CE$\nu$NS measurements with cryogenic sapphire detectors, opening opportunities to probe nuclear form factors, constrain non-standard neutrino interactions, and explore beyond-Standard-Model signatures.
| Position | PhD student |
|---|---|
| Affiliation | National Institute of Science education and Research |
| Country | India |