Neutral current coherent pion production

We investigate the neutrino induced coherent pion production reaction at low and intermediate energies. The model includes pion, nucleon and Delta(1232) resonance as the relevant hadronic degrees of freedom. Nuclear medium effects on the production mechanisms and pion distortion are taken into account. We obtain that the dominance of the Delta excitation holds due to large cancellations among the background contributions. We consider two sets of vector and axial-vector N-Delta transition form-factors, evidencing the strong sensitivity of the results to the axial coupling C5A(0). The differences between neutrino and antineutrino cross sections, emerging from interference terms, are also discussed.Comment: 4 pages, 3 figures, minor corrections, a few references adde

Weak Neutral Current Studies with Positrons

Weak neutral current interactions with charged leptons have offered unique opportunities to study novel aspects of hadronic structure and search for physics beyond the standard model. These studies in the medium energy community have been primarily through parity-violating processes with electron beams, but with the possibility of polarized positron beams, new and complementary observables can be considered in experiments analogous to their electron counterparts. Such studies include elastic proton, deep inelastic, and electron target scattering. Potential positron neutral current experiments along with their potential physics reach, requirements, and feasibility are presented

Neutral-current neutrino-nucleus quasielastic scattering

A relativistic distorted-wave impulse-approximation model to quasielastic neutral-current neutrino-nucleus scattering is developed, using the relativistic mean field theory for the bound state and taking into account the final state interaction in the relativistic scattering state. Results for the neutrino (antineutrino) reaction on 12C target nucleus are presented in an energy range between 500 and 1000 MeV. The sensitivity to the strange quark content of the axial-vector form factor is discussed.Comment: 12 pages, 9 figure

Neutral Current π0\pi^0 Production in MiniBooNE

This paper describes the analysis used to determine the neutral current $\pi^0$ production in MiniBooNE in bins of momentum. Additionally, a measurement of the relative coherent production of $\pi^0$s is discussed. The coherent production rate is found to be (19.5 $\pm$1.1 (stat) $\pm$2.5 (sys))% of the total exclusive neutral current $\pi^0$ production rate.Comment: Prepared for the Proceedings of Neutrino Interactions 200

Probing Supersymmetry with Neutral Current Scattering Experiments

We compute the supersymmetric contributions to the weak charges of the electron and proton in the framework of Minimal Supersymmetric Standard Model. We also consider the ratio of neutral current to charged current cross sections, R_nu and R_nubar at nu (nubar)-nucleus deep inelastic scattering, and compare the supersymmetric corrections with the deviations of these quantities from the Standard Model predictions implied by the recent NuTeV measurement.Comment: 4 pages, contribution to the proceedings of CIPANP 2003 (May, 2003), New York Cit

Neutral-current neutrino reactions in the supernova environment

We study the neutral-current neutrino scattering for four nuclei in the iron region. We evaluate the cross sections for the relevant temperatures during the supernova core collapse and derive Gamow-Teller distributions from large-scale shell-model calculations. We show that the thermal population of the excited states significantly enhances the cross sections at low neutrino energies. Calculations of the outgoing neutrino spectra indicate the prospect of neutrino upscattering at finite temperatures. Both results are particularly notable in even-even nuclei.Comment: 14 pages, 4 figures, accepted in Phys. Lett. B