Neutrino-Nucleon Scattering Research Articles

Radiative Corrections to Neutron Beta Decay and (Anti)Neutrino-Nucleon Scattering from Low-Energy Effective Field Theory

Radiative Corrections to Neutron Beta Decay and (Anti)Neutrino-Nucleon Scattering from Low-Energy Effective Field Theory

PHOTON-NEUTRINO INTERACTION IN θ-EXACT COVARIANT MODEL: PHENOMENOLOGY AND QUANTUM PROPERTIES

We construct the theta-exact covariant noncommutative model and obtain various closed constraints on the noncommutative scale from inelastic neutrino-nucleon scatterings, from plasmon decay into neutrino pair, from the Big Bang Nucleosynthesis and from the reheating phase after inflation, respectively. We find neutrino two-point function in a closed form and decoupling of the UV divergent term from softened UV/IR mixing term. Deformed dispersion relations at low energies are capable to account for the recent results from the OPERA collaboration on the superluminal speed of the muon neutrinos.

The decay of tau leptons produced in neutrino–nucleon scatterings

Energy and angular distributions of the τ decay products in the CERN-to-Gran Sasso ν τ appearance experiments are studied for the decay modes τ → π ν and τ → ℓ ν ¯ ν ( ℓ = e or μ). We find that the decay particle distributions in the laboratory frame are significantly affected by the τ polarization. Rather strong azimuthal asymmetry of π − and ℓ − about the τ momentum axis is predicted, which may have observable consequences even at small statistics experiments.

WHAT DO WE MEAN BY DETECTING EARTH-SKIMMING NEUTRINOS?

In this talk, we elaborate the strategy for detecting the Earth-skimming tau neutrinos. We first show that there are non-negligible astrophysical tau neutrino fluxes due to neutrino flavor oscillations. We then illustrate the idea of detecting Earth-skimming tau neutrinos. In particular, we point out that the tau-lepton flux resulting from neutrino-nucleon scatterings inside the earth is controlled by the tau-lepton range. We demonstrate this observation by showing the tau-lepton flux induced by the GZK tau-neutrino flux. The question on the energy resolutions of tau neutrinos in this detection strategy is briefly discussed.

Polarization of Tau Leptons Produced in Neutrino-Nucleon Scattering

Polarization of Tau Leptons Produced in Neutrino-Nucleon Scattering

Asymmetric neutrino emission due to neutrino-nucleon scatterings in supernova magnetic fields

We derive the cross section of neutrino-nucleon scatterings in supernova magnetic fields, including weak-magnetism and recoil corrections. Since the weak interaction violates the parity, the scattering cross section asymmetrically depends on the directions of the neutrino momenta to the magnetic field; the origin of pulsar kicks may be explained by the mechanism. An asymmetric neutrino emission (a drift flux) due to neutrino-nucleon scatterings is absent at the leading level of $\mathcal O(\mu_BB/T)$, where $\mu_B$ is the nucleon magneton, $B$ is the magnetic field strength, and $T$ is the matter temperature at a neutrinosphere. This is because at this level the drift flux of the neutrinos are exactly canceled by that of the antineutrinos. Hence, the relevant asymmetry in the neutrino emission is suppressed by much smaller coefficient of $\mathcal O(\mu_BB/m)$, where $m$ is the nucleon mass; detailed form of the relevant drift flux is also derived from the scattering cross section, using a simple diffusion approximation. It appears that the asymmetric neutrino emission is too small to induce the observed pulsar kicks. However, we note the fact that the drift flux is proportional to the deviation of the neutrino distribution function from the value of thermal equilibrium at neutrinosphere. Since the deviation can be large for non-electron neutrinos, it is expected that there occurs cancellation between the deviation and the small suppression factor of $\mathcal O(\mu_BB/m)$. Using a simple parameterization, we show that the drift flux due to neutrino-nucleon scatterings may be comparable to the leading term due to beta processes with nucleons, which has been estimated to give a relevant kick velocity when the magnetic field is sufficiently strong as $10^{15}$--$10^{16}$ G.

Parity Violation in Neutrino Transport and the Origin of Pulsar Kicks

In proto-neutron stars with strong magnetic fields, the neutrino-nucleon scattering/absorption cross sections depend on the direction of neutrino momentum with respect to the magnetic field axis, a manifestation of parity violation in weak interactions. We study the deleptonization and thermal cooling (via neutrino emission) of proto-neutron stars in the presence of such asymmetric neutrino opacities. Significant asymmetry in neutrino emission is obtained because of multiple neutrino-nucleon scatterings. For an ordered magnetic field threading the neutron star interior, the fractional asymmetry in neutrino emission is about 0.006(B/1014 G), corresponding to a pulsar kick velocity of about 200(B/1014 G) km s−1 for a total radiated neutrino energy of 3×1053 ergs.

Evidence for Color-Excitation in Deep-Inelastic Charged-Current Neutrino-Nucleon Scattering

Aiming at a search for possible color-excitation, deep-inelastic neutrino-nucleon scattering, νµ(νµ) + N →µ∓ + X, is analysed with a weak interaction model incorporating a color-changing current in addition to the standard GIM current. Various quantities of experimental interest are evaluated as functions of incident neutrino energy E and compared with the latest CDHS, BEBC and CIFR data as well as the lower-energy GGM data. Negative scalling violation is taken into account by a propagator-like parametrization. It is shown that (i) these neutrino data do not exclude a weak-boson of mass as low as ∼15 GeV; (ii) there is, particularly in the BEBC and CIFR data, some evidence in favor of positive scaling violation which indicates onset of new production channel (s); and (iii) the color-excitation with threshold at mX∼10 GeV is one probable explanation of the latter behavior.

Neutrino-Nucleon Scattering under Scaling Violation

Neutrino-nucleon scatterings are discussed within the framework of the Wilson operator product expancsion assuming that observed scaling violations are clue to the field theoretical origin. It is shown that the total cross sections rise linealy with initial neutrino energy and the neutrino total cross section becomes equal to the antineutrino cross section at sufficiently high energy. The numerical value of muon inelasticity is estimated to be 9/16. The average value of q' is also discussed.

Radiative Corrections to Deep-Inelastic Neutrino-Nucleon Scattering

A simple parton model is used to estimate the radiative corrections to neutrino-induced inclusive processes. An application of the resulting expressions to ${\ensuremath{\nu}}_{\ensuremath{\mu}}+p\ensuremath{\rightarrow}{\ensuremath{\mu}}^{\ensuremath{-}}+X$ at ${E}_{\ensuremath{\nu}}^{\mathrm{LAB}}=100$ GeV shows that the muon spectrum is distorted by as much as 10% in some regions.

Relations Among the Structure Functions of Deep-Inelastic Neutrino-Nucleon Scattering

Light-cone current commutators are used to derive relations between the structure functions of the vector-vector part of neutrino-nucleon scattering and the structure functions of the vector-axial-vector part.