Measurement of Charged Current Coherent Pion Production by Neutrinos on Carbon at MINER$\nu$A

Abstract

Neutrino-nucleus coherent pion production is a rare neutrino scattering process where the squared four-momentum transferred to the nucleus is small, a lepton and pion are produced in the forward direction, and the nucleus remains in its initial state. This process is an important background in neutrino oscillation experiments. Measurements of coherent pion production are needed to constrain models which are used to predict coherent pion production in oscillation experiments. This thesis reports measurements of vm and -vm charged current coherent pion production on carbon for neutrino energies in the range 2 < Ev < 20 GeV. The measurements were made using data from MINERvA, which is a dedicated neutrino-nucleus scattering experiment that uses a fine-grained scintillator tracking detector in the high-intensity NuMI neutrino beam at Fermilab. Coherent interactions were isolated from the data using only model-independent signatures of the reaction, which are a forward muon and pion, no evidence of nuclear breakup, and small four-momentum transfer to the nucleus. The measurements were compared to the coherent pion production model used by oscillation experiments. The data and model agree in the total interaction rate and are similar in the dependence of the interaction rate on the squared four- momentum transferred from the neutrino. The data and model disagree significantly in the pion kinematics. The measured vm and -vm interaction rates are consistent, which supports model predictions that the neutrino and antineutrino interaction rates are equal.