Coherent elastic neutrino nucleus scatter response of semiconductor detectors to nuclear reactor antineutrinos

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 1004; p. 165342
• Main Authors: Ang, Wei Eng, Prasad, Shikha, Mahapatra, Rupak
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 11-07-2021
• Subjects: CE[formula omitted]NS; Coherent elastic neutrino nucleus scatter; Reactor antineutrino measurement; Semiconductor detectors; Semiconductor detectors; Coherent elastic neutrino nucleus scatter; Reactor antineutrino measurement; CEνNS
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2021.165342

We studied the performance of advanced semiconductor detectors to measure reactor antineutrino with the potential to drastically improve efficiency and lower existing thresholds of detectable incident-antineutrino-energy. Recent developments, such as those by the Mitchell Institute Neutrino Experiment at Reactor (MINER) experiment at Texas A&M University, in semiconductor technologies have enabled the ability to lower the coherent-elastic-neutrino-nucleus-scatter (CEνNS) based detection threshold to nuclear recoil energies between 10-eV and 100-eV (Dutta et al., 2016). Existing detectors based on inverse beta decay (IBD) have a threshold of 1.806 MeV (Oralbaev et al., 2016). In this study, we calculated the CEνNS response of semiconductor detectors to antineutrino flux from a 1-MW(th) TRIGA reactor as a function of incident antineutrino energy. In the calculations, the reaction rates of detectors made of germanium and silicon are calculated for a 100-kg detector and placed 10 m from the core. No background radiation characterization and reduction were performed. First, the reactor antineutrino flux spectrum is obtained for the fuel composition specific to 1-MW(th) TRIGA reactor without any thresholds. Next, the standard model (SM) of physics is used to calculate the CEνNS cross-section as a function of incident antineutrino energy. Finally, the above two functions are convolved to provide the detector response for both, germanium and silicon detectors. The results show that germanium has a greater efficiency than silicon; however, it is shown that silicon is sensitive to lower antineutrino energies. It is found that a 100-eV nuclear recoil in germanium semiconductor detectors can be produced by a minimum incident energy of 1.84 MeV antineutrinos, and in silicon by 1.14 MeV antineutrinos. For the lower threshold, a 20-eV nuclear recoil in germanium semiconductors can be produced by a minimum incident energy of 0.82 MeV antineutrinos and in Si by 0.51 MeV antineutrinos. Lowering the detector response energy sensitivity equips us with newer techniques for nuclear fuel monitoring.