Coherent Elastic Neutrino-Nucleus Scattering Experiments and Sterile Neutrino Searches Using Reactor Antineutrinos in India
Scientists in India pursue reactor-based neutrino experiments with clear goals. They focus on coherent elastic neutrino-nucleus scattering and sterile neutrino searches. Research teams place detectors near research reactors at Bhabha Atomic Research Centre. These setups use electron antineutrinos produced in fission processes.
The Indian Scintillator Matrix for Reactor Anti-Neutrinos operates at the Dhruva research reactor. Researchers deploy a one-ton plastic scintillator array about thirteen metres from the core. They detect antineutrinos through the inverse beta decay process. The experiment collects data continuously since early 2022. Teams measure the antineutrino spectrum from a natural uranium fuelled core. This approach differs from earlier studies that relied on highly enriched fuel.
Scientists search for sterile neutrinos through short-baseline oscillations. They test the three-active-plus-one-sterile neutrino model. Detector placements at near and far positions improve sensitivity. Analysis shows the setup can constrain mixing parameters in the reactor antineutrino anomaly region. An exposure of one ton-year allows meaningful limits on the mixing angle at mass-squared differences near one electronvolt squared.
Parallel efforts target coherent elastic neutrino-nucleus scattering. Proposed experiments such as the Indian Coherent Neutrino-nucleus Scattering Experiment use the Apsara-U reactor. The compact and movable core of this reactor reduces systematic uncertainties. Low-threshold detectors including sapphire and high-purity germanium record nuclear recoils at the kiloelectronvolt scale. Coherent scattering offers a larger cross-section than inverse beta decay at low energies.
Researchers explore physics beyond the Standard Model with these detectors. They constrain non-standard neutrino interactions and light mediators. Teams also examine the weak mixing angle at low momentum transfer. Additional studies probe neutrino electromagnetic properties such as magnetic moments. Reactor monitoring applications emerge as a practical benefit. Spectral information helps track fuel composition and power levels without intrusive methods.
These Indian programmes combine fundamental physics with applied reactor safeguards. Short-baseline measurements address the reactor antineutrino anomaly directly. Low-energy coherent scattering opens new windows into nuclear and particle interactions. Continued data collection and detector improvements strengthen the overall scientific reach.