Oscillation tomography of the Earth with solar neutrinos and future experiments

Abstract

We study in details the Earth matter effects on the boron neutrinos from the Sun using recently developed 3D models of the Earth. The models have a number of new features of the density profiles, in particular, substantial deviation from spherical symmetry. In this connection we further elaborate on relevant aspects of oscillations ( 2 corrections, adiabaticity violation, entanglement, etc.) and the attenuation effect. The night excesses of the νe− and νN − events and the Day-Night asymmetries, AND, are presented in terms of the matter potential and the generalized energy resolution functions. The energy dependences of the cross-section and the flux improve the resolution, and consequently, sensitivity to remote structures of the profiles. The nadir angle (η) dependences of AND are computed for future detectors DUNE, THEIA, Hyper-Kamiokande and MICA at the South pole. Perspectives of the oscillation tomography of the Earth with the boron neutrinos are discussed. Next generation of detectors will establish the integrated day-hight asymmetry with high confidence level. They can give some indications of the η− dependence of the effect, but will discriminate among different models at most at the (1 − 2)σ level. For the high level discrimination, the MICA-scale experiments are needed. MICA can detect the ice-soil borders and perform unique tomography of Antarctica.

Sensitivities of future solar neutrino observatories to NSI

“…During the night, neutrinos travel a larger distance to reach the detector because of propagation through the Earth. The differences of survival probability during night and day is given by [39,40] ∆P (E, η)…”

“…where a E CC ≡ 2V (x)E/∆m 2 21 and ∆ 21 ≡ ∆m 2 21 /4E. As discussed in [40] we can neglect I 2 in our calculations. For a constant density…”

“…Notice that only 9.7% of 8 B neutrinos have energy E ν > 11 MeV but due to strong energy dependence (42) the corresponding fraction of the detected events is 0.9. We find that about 27000 events of ν e will be detected annually for E ν > 11 MeV in a 40 kt liquid argon detector considering neutrino interaction with argon nuclei [40,42]. We have assumed the energy resolution of DUNE is σ E /E = 0.07.…”

“…In addition, we have assumed the same details of analysis as given in Ref. [40]. For the statistical inferences we have considered Asimov data set approximation, and the true model is the standard model or f αβ = 0.…”

Accounting for the Heisenberg and Pauli principles in the kinetic approach to neutrino oscillations

“…figure 1 in reference [40]. The night-day asymmetry [39,41], A N D = [P e (t N ) − P e (t D )]/P e (t D ), computed numerically as a function of cos(η) for the neutrino energy E = 10 MeV is presented in the right panel of figure 2. Its shape can be qualitatively understood in the two-layer approximation, that distinguishes only between the mantle and the core.…”