Muon Neutrino Cross Sections Research Articles

Measurement of differential cross sections for νμ -Ar charged-current interactions with protons and no pions in the final state with the MicroBooNE detector

We present an analysis of MicroBooNE data with a signature of one muon, no pions, and at least one proton above a momentum threshold of 300 MeV/c (CC0πNp). This is the first differential cross-section measurement of this topology in neutrino-argon interactions. We achieve a significantly lower proton momentum threshold than previous carbon and scintillator-based experiments. Using data collected from a total of approximately 1.6×1020 protons on target, we measure the muon neutrino cross section for the CC0πNp interaction channel in argon at MicroBooNE in the Booster Neutrino Beam which has a mean energy of around 800 MeV. We present the results from a data sample with estimated efficiency of 29% and purity of 76% as differential cross sections in five reconstructed variables: the muon momentum and polar angle, the leading proton momentum and polar angle, and the muon-proton opening angle. We include smearing matrices that can be used to “forward fold” theoretical predictions for comparison with these data. We compare the measured differential cross sections to a number of recent theory predictions demonstrating largely good agreement with this first-ever dataset on argon.36 MoreReceived 7 October 2020Accepted 24 November 2020DOI:https://doi.org/10.1103/PhysRevD.102.112013Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.Published by the American Physical SocietyPhysics Subject Headings (PhySH)Research AreasNucleus-neutrino interactionsParticles & Fields

New experiment at J-PARC to measure the muon neutrino cross section ratio between water and hydrocarbon

A new experiment, named WAGASCI can precisely measure the ratio of muon neutrino cross sections between water and hydrocarbon for charged-current interactions with a large angular acceptance at J-PARC. A new detector mainly consists of two water target modules and two hydrocarbon target modules. Each module is composed of scintillators aligned in a 3D grid-like structure having almost 4π solid angle acceptance. Each scintillator has a groove for a WLS fiber to be put on, and they are glued with the optical cement by using a semi-automated gluing system. WLS fibers are connected to Multi-Pixel Photon Counters (MPPCs), which are crosstalk suppression type. The detector is now under construction, and we will start taking the data in 2017.

On the impact of systematical uncertainties for the CP violation measurement in superbeam experiments

Superbeam experiments can, in principle, achieve impressive sensitivities for CP violation in neutrino oscillations for large �13. We study how those sensitivities depend on assumptions about systematical uncertainties. We focus on the second phase of T2K, the so-called T2HK experiment, and we explicitly include a near detector in the analysis. Our main result is that even an idealised near detector cannot remove the dependence on systematical uncertainties completely. Thus additional information is required. We identify certain combinations of uncertainties, which are the key to improve the sensitivity to CP violation, for example the ratio of electron to muon neutrino cross sections and efficiencies. For uncertainties on this ratio larger than 2%, T2HK is systematics dominated. We briefly discuss how our results apply to a possible two far detector configuration, called T2KK. We do not find a significant advantage with respect to the reduction of systematical errors for the measurement of CP violation for this setup.

Inadequacy of scaling arguments for neutrino cross sections

The problem with the use of scaling arguments for simultaneous studies of different weak interaction processes is discussed. When different neutrino scattering cross sections involving quite different momentum transfers are being compared it difficult to define a meaningful single scaling factor to renormalize calculated cross sections. It has been suggested that the use of such scaling can be used to estimate high energy neutrino cross sections from low energy neutrino cross sections. This argument has lead to questions on the consistency of the magnitude of the LSND muon neutrino cross sections on $^{12}$C relative to other lower energy weak processes. The issue is revisited here and from inspection of the structure of the form factors involved it is seen that the problem arises from a poor description of the transition form factors at high momentum transfer. When wave functions that reproduce the transverse magnetic inelastic (e,e') scattering form factor for the 15.11 MeV state in $^{12}$C are used there is no longer a need for scaling the axial current, and the different weak interactions rates involving the T=1 1$^+$ triplet in mass 12 are consistent with one another.

Inclusive neutrino and antineutrino reactions in 56Fe

We obtain cross sections for the inclusive neutrino and antineutrino reactions in 56Fe for the processes νe + 56Fe ⟶ e− + X, ν̄e + 56Fe ⟶ e+ + X, νμ + 56Fe ⟶ μ− + X and ν̄μ + 56Fe ⟶ μ+ + X. For the former two reactions we do this for incident neutrino energies from threshold to 240 MeV and for the latter two reactions from threshold to 300 MeV. We make use of a tensor model, which depends upon data obtained from the total muon capture rate in 56Fe, to calculate our results. We also obtain the electron neutrino cross section averaged over the Michel spectrum and the muon neutrino cross section averaged over the LAMPF muon neutrino spectrum. We find that these cross sections are substantial as would be expected from the neutron content of the 56Fe nucleus and might therefore be a serious background for nuclear neutrino experiments with substantial iron or steel shielding. We compare our calculation with the experimental results of the KARMEN Collaboration and discuss our results in light of planned experiments in iron.