Coherent elastic neutrino nucleus scatter response of semiconductor detectors to nuclear reactor antineutrinos
and
Update on MINER activities at Texas A&M University

By Wei-Eng Ang
Abstract
This talk will demonstrate if a recently demonstrated detection mechanism coherent-neutrino-nucleus-scatter (CEνNS) can be the next generation of viable/deployable detector technology to measure antineutrinos from nuclear reactors. CEνNS, although hypothesized nearly 50 years ago, was demonstrated only in 2017 by the COHERENT collaboration using scintillation-based detectors. In this study, we will study the applicability of semiconductor detectors to CEνNS (developed by the MINER collaboration) for antineutrino detection with the aims of achieving very low thresholds and high intrinsic detection efficiency. To demonstrate these improvements, we will provide CEνNS detection rates in Ge and Si detectors. In our approach, first the reactor antineutrino energy spectrum modelling is performed using the summation method for a 1-MW TRIGA reactor at Texas A&M.  We compare our summation method results to other past works to verify our calculations. Next, the standard model of physics is used to calculate CEνNS cross-section as function energy. Finally, the detector response spectrum of semiconductor detectors using natural germanium (Ge) and silicon (Si) are calculated. These response rates are also compared with the current-state-of-the-art inverse beta decay (IBD) based detectors. The calculations assume semiconductor detectors with a mass of 100 kg, placed at a distance of 10 m from the 1 MW TRIGA reactor core. The results show that the Ge detector provides an improvement over the IBD detector of the same size by a factor of 24, while in the case of Si the improvement is a factor of 4. It also found that Ge and Si detectors have lower energy threshold compared to IBD (1.806 MeV). For a 20-eV nuclear recoil threshold, Ge detector and Si detector can detect antineutrino energies above 0.82 MeV and 0.51 MeV respectively. In our future work, we will extend the calculations on a commercial reactor such as AP1000 and conduct nonproliferation analysis by considering several diversion cases.
At the end of our talk we will also provide a quick update on the most recent developments of the MINER collaboration.
Biosketch
Wei Eng Ang is a final year Ph.D. candidate in the Department of Nuclear Engineering, Texas A&M University. He is currently working on nonproliferation and security applications of antineutrino detection, especially using CEνNS-based-detectors being developed by the MINER collaboration.