Exploring the Earth matter effect with atmospheric neutrinos in ice

Abstract

We study the possibility to perform neutrino oscillation tomography and to determine the neutrino mass hierarchy in kilometer-scale ice Čerenkov detectors by means of the θ 13 -driven matter effects which occur during the propagation of atmospheric neutrinos deep through the Earth. We consider the ongoing IceCube/DeepCore neutrino observatory and future planned extensions, such as the PINGU detector, which has a lower energy threshold. Our simulations include the impact of marginalization over the neutrino oscillation parameters and a fully correlated systematic uncertainty on the total number of events. For the current best-fit value of the mixing angle θ 13 , the DeepCore detector, due to its relatively high-energy threshold, could only be sensitive to fluctuations on the normalization of the Earth's density of ∆ρ ±10% at ∼ 1.6σ CL after 10 years in the case of a true normal hierarchy. For the two PINGU configurations we consider, overall density fluctuations of ∆ρ ±3% (±2%) could be measured at the 2σ CL after 10 years, also in the case of a normal mass hierarchy. We also compare the prospects to determine the neutrino mass hierarchy in these three configurations and find that this could be achieved at the 5σ CL, for both hierarchies, after 5 years in DeepCore and about 1 year in PINGU. This clearly shows the importance of lowering the energy threshold below 10 GeV so that detectors are fully sensitive to the resonant matter effects.

Validating the Earth's Core using Atmospheric Neutrinos with ICAL at INO

“…The neutrino-based absorption tomography of Earth has been performed using atmospheric neutrino data at IceCube detector [30]. On the other hand, the neutrino oscillation tomography relies on the matter effects in neutrino oscillations which has been considered by the study of man-made beams [31][32][33][34][35][36][37][38][39][40][41], atmospheric [42][43][44][45], solar [46,47], and supernova [47,48] neutrinos. The third possibility of Earth tomography using the study of diffraction pattern produced by coherent neutrino scattering in crystalline matter inside Earth is technologically not feasible [49].…”

Neutrino Oscillations through the Earth's Core

“…During propagation in matter, neutrino oscillations are modified by the presence of electrons [22]. This allows one, in principle, to probe the electron number density of dense materials [23][24][25][26][27] assuming either the oscillation parameters are measured in vacuum or measurements are made in different environments.…”

Neutrino Tomography of the Earth with ORCA Detector

“…In the somewhat related studies [46][47][48] the authors have analysed the IceCube sensitivity to the Earth matter effects in oscillations of atmospheric neutrinos [46] and the IceCube [47] and ORCA [48] sensitivities to the Earth core composition. In [47,48] the PREM density distribution of the Earth core was used as input in the corresponding analyses.…”