Speaker
Description
The question of whether neutrinos follow inverted or normal mass hierarchy and the CP violation parameter $\delta_{CP}$ in the neutrino sector (which may help understand the matter antimatter asymmetry etc.), are some of the important goals of current and future neutrino experiments. Cosmology provides constraints on total neutrino mass, $N_{eff}$ (and implications for mass hierarchy). Whereas for the accurate measurement of various neutrino parameters, a deep understanding of neutrino-target interactions is crucial to reduce the systematic uncertainties. We investigate the effect of final-state interactions (FSI) in the charge current quasi-elastic (CCQE) channel by reconstructing the neutrino energy using the calorimetric method. A selection of events with 1 proton, 0 pion, and any number of neutrons in the final state reduces the discrepancy between reconstructed and true neutrino energy for the CCQE process analysed for DUNE and MicroBooNE using Monte-Carlo simulations. Since the reconstruction of neutrino energy is important for improving cross-section measurements, the Kaon-Decays-At-Rest (KDAR) neutrinos provide an opportunity to study the neutrino interactions in the low-energy regime with a known neutrino energy of 235.5 MeV. We explore the missing energy in KDAR $\nu_{\mu}$ CC scattering on Carbon in JSNS2 using MC generators. In addition to FSI, the initial state of nucleon also affects the cross-section measurements. We discuss the same in some specific cases. Neutrino oscillation implying the physics beyond the standard model, we explore a BSM scenario, Lepton flavour violation (LFV) is considered to be a suitable avenue. We study the charged LFV $\mu$ decays such as $\mu$ → 𝑒$\gamma$, $\mu$ → 𝑒𝑒𝑒, and ($\mu$ − 𝑒) Ti with a vector leptoquark ($𝑈_3$) by considering the constraints from non-standard neutrino interaction (NSI) sector parameter $\epsilon_{𝑒\mu}$. Here we consider that these NSIs are attributed to the presence of leptoquarks (hypothetical particles which can also help understand some anomalies) account for the difference in the experimental observations of $\delta_{𝐶𝑃}$ measurement by NOvA and T2K and obtain the branching ratios (BR) for the LFV processes. The enhanced BR predictions potentially could be verified in the far future.