# [Seminar] Dr.Anil Kumar ( IOP Bhubaneswar, SINP Kolkata, HBNI Mumbai, India), 28th May, 2021

We are delighted to notice that there we will have a seminar talk about neutrino physics with Dr.Anil Kumar, from IOP Bhubaneswar, SINP Kolkata, HBNI Mumbai, India

Title : Exploring Oscillation Dip and Valley, NSI, and Earth’s Core using Atmospheric Neutrinos at INO-ICAL Detector
Speaker : Dr.Anil Kumar
Date & time : 10:00 AM 28th, May, 2021
The 50 kt magnetized Iron Calorimeter (ICAL) detector at the proposed India-based Neutrino Observatory (INO) aims to detect atmospheric neutrinos and antineutrinos separately in the multi-GeV range of energies and over a wide range of baselines. By utilizing its charge identification capability, ICAL can efficiently distinguish $\mu^-$ and $\mu^+$ events and hence, the parent particles $\nu_\mu$ and $\bar{\nu}_\mu$. We demonstrate for the first time that the oscillation dip and valley can be reconstructed using the ratio of upward-going and downward-going reconstructed muon events at ICAL separately for $\mu^-$ and $\mu^+$. The location of dip and the alignment of valley is used to constrain the atmospheric mass-squared difference in two separate ways. Further, we propose a new approach to explore the neutral-current non-standard neutrino interaction (NSI) parameter $\varepsilon_{\mu\tau}$ in atmospheric neutrino experiments using oscillation dips and valleys. We show that non-zero $\varepsilon_{\mu\tau}$ shifts the oscillation dip locations and bends the oscillation valley. Thanks to the charge identification capability of ICAL, the opposite shifts in the locations of oscillation dips as well as the contrast in the curvatures of oscillation valleys for $\mu^-$ and $\mu^+$ is used to constrain $|\varepsilon_{\mu\tau}|$. Next, we explore the possibility of utilizing neutrino oscillations in the presence of matter to extract information about the internal structure of Earth complementary to seismic studies. Using good directional resolution, ICAL would be able to observe 331 $\mu^-$ and 146 $\mu^+$ core-passing events with 500 kt$\cdot$yr exposure. With this exposure, we show for the first time that the presence of Earth’s core can be independently confirmed at ICAL with a median $\Delta \chi^2$ of 7.45 (4.83) assuming normal (inverted) mass ordering by ruling out the simple two-layered mantle-crust profile in theory while generating the prospective data with the PREM profile.