Resonance refraction and neutrino oscillations

Abstract

The refraction index and matter potential depend on neutrino energy and this dependence has a resonance character associated to the production of the mediator in the s−channel. For light mediators and light particles of medium (background) the resonance can be realized at energies accessible to laboratory experiments. We study properties of the energy dependence of the potential for different C-asymmetries of background. Interplay of the background potential and the vacuum term leads to (i) bump in the oscillation probability in the resonance region, (ii) dip related to the MSW resonance in the background, (iii) substantial deviation of the effective ∆m2 above the resonance from the low energy value, etc. We considered generation of mixing in the background. Interactions with background shifts the energy of usual MSW resonance and produces new MSW resonances. Searches of the background effects allow us to put bounds on new interactions of neutrinos and properties of the background. We show that explanation of the MiniBooNE excess, as the bump due to resonance refraction, is excluded.

Quasi-Sterile Neutrinos from Dark Sectors I. BSM matter effects in neutrino oscillations and the short-baseline anomalies

“…Importantly, at high very neutrino energies E ν → ∞, the active neutrino ν 3 receives an effective contribution to its mass of δm 2 3 = sin 2 θ S 3 δM 2 3 (note (2.17d)), an effect that has been previously noted in [57][58][59][60]. Compatibility with observations from high energy atmospheric and accelerator neutrinos then enforces only two possibilities:…”

“…In the 'oscillatory' approaches, BSM effects alter neutrino propagation through a medium (either ordinary matter [53], the CνB [54], or extra dimensions [55,56]), leading to resonant neutrino oscillations within the window of energy where the MiniBooNE low energy excess is concentrated. Previous attempts to implement oscillatory approaches have not been successful, however, because new matter effects invariably alter the effective in-medium mass splittings of active neutrinos [57][58][59][60], leading to oscillation probabilities incompatible with observations at long-baseline neutrino experiments.…”

Neutrino Transition in Dark Matter

“…In Fig. 2, the lower black and upper gray solid lines show the bounds from ( 17) and (18), respectively. Also shown are the upper limits on the neutrino-dark matter interactions obtained from SN1987A and IceCube-170922A observations.…”

“…As the classical amplitude of such a dark matter may be as large as φ 0 ∼ 10 11 GeV(10 −22 eV/m φ ) GeV, it can also alter the Standard Model dynamics when it couples to quarks and leptons. In recent years, its relevance to neutrino physics has been explored extensively [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] as the neutrino sector would require some new physics for the origin of tiny neutrino masses. The ultralight dark matter coupling to neutrinos modifies the standard neutrino oscillations in various ways and thus may hint at some anomalous phenomena in observations.…”

Probing Secret Interactions of Astrophysical Neutrinos in the High-Statistics Era

“…In that scenario, neutrinos interact with a light boson, increasing the neutrino-neutrino scattering rate with respect to that of the standard model. Laboratory limits, mostly from meson-decay experiments, are relatively weak [5,6], allowing νSI to have large effects, potentially explaining short baseline neutrino anomalies [7][8][9][10][11][12] and the muon g − 2 anomaly [13][14][15][16][17].…”