Enhancing sensitivity to non-standard neutrino interactions at INO combining muon and hadron information

Abstract

AbstractIn this paper, we explore the impact of flavor violating neutral current non-standard interaction (NSI) parameter $$\varepsilon _{\mu \tau }$$εμτ in the oscillation of atmospheric neutrinos and antineutrinos separately using the 50 kt magnetized ICAL detector at INO. We find that due to non-zero $$\varepsilon _{\mu \tau }$$εμτ, $$\nu _\mu \rightarrow \nu _\mu $$νμ→νμ and $${\bar{\nu }}_\mu \rightarrow {\bar{\nu }}_\mu $$ν¯μ→ν¯μ transition probabilities get modified substantially at higher energies and longer baselines, where vacuum oscillation dominates. We demonstrate for the first time that by adding the hadron energy information along with the muon energy and muon direction in each event, the sensitivity of ICAL to the NSI parameter $$\varepsilon _{\mu \tau }$$εμτ can be enhanced significantly. The most optimistic bound on $$\varepsilon _{\mu \tau }$$εμτ that we obtain is $$-\,\,0.01< \varepsilon _{\mu \tau } < 0.01 $$-0.01<εμτ<0.01 at 90$$\%$$% C.L. using 500 kt$$\cdot $$·yr exposure and considering $$E_\mu $$Eμ, $$\cos \theta _\mu $$cosθμ, and $$E'_{\mathrm{had}}$$Ehad′ as observables in their ranges of [1, 21] GeV, [−  1, 1], and [0, 25] GeV, respectively. We discuss for the first time the importance of the charge identification capability of the ICAL detector to have better constraints on $$\varepsilon _{\mu \tau }$$εμτ. We also study the impact of non-zero $$\varepsilon _{\mu \tau }$$εμτ on mass hierarchy determination and precision measurement of oscillation parameters.