Invariant amplitudes, unpolarized cross sections, and polarization asymmetries in (anti)neutrino-nucleon elastic scattering

At leading order in weak and electromagnetic couplings, cross sections for (anti)neutrino-nucleon elastic scattering are determined by four nucleon form factors that depend on the momentum transfer $Q^2$. Including radiative corrections in the Standard Model and potential new physics contributions beyond the Standard Model, eight invariant amplitudes are possible, depending on both $Q^2$ and the (anti)neutrino energy $E_\nu$. We review the definition of these amplitudes and use them to compute both unpolarized and polarized observables including radiative corrections. We show that unpolarized accelerator neutrino cross-section measurements can probe new physics parameter space within the constraints inferred from precision beta decay measurements.Comment: 65 pages, 89 figure

Study of quasi-elastic scattering in the NOvA detector prototype

University of Minnesota Ph.D. dissertation. June 2013. Major: Physics. Advisor: Prof. Kenneth Heller. 1 computer file (PDF); ix, 153 pages, appendices A-C.NOvA is a 810 km long base-line neutrino oscillation experiment with two detectors (far 14 KTon and near detector 300 Ton) currently being installed in the NUMI off-axis neutrino beam produced at Fermilab. A 222 Ton prototype NOvA detector (NDOS) was built and operated in the neutrino beam for over a year to understand the response of the detector and its construction. The goal of this thesis is to study the muon neutrino interaction data collected in this test, specifically the identification of quasi-elastic charged-current interactions and measure the behavior of the quasi-elastic muon neutrino cross section. This thesis presents the analysis of the data from two detector configurations, the first configuration collected data from 1e19 protons on target (POT) from April to May 2011 and the second configuration collected data from 1.7e20POT from October 2011 to April 2012. The charged current quasi-elastic muon neutrino events collected with each configuration were analyzed to extract the cross section as a function of energy as well as the single differential cross sections with respect to outgoing muon momentum, outgoing muon angle from the incident neutrino direction; and the momentum dP, and transfer squared of the interaction.Betancourt, Minerba. (2013). Study of quasi-elastic scattering in the NOvA detector prototype. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/155571

Deuterium target data for precision neutrino-nucleus cross sections

Amplitudes derived from scattering data on elementary targets are basic inputs to neutrino-nucleus cross section predictions. A prominent example is the isovector axial nucleon form factor, FA(q2), which controls charged current signal processes at accelerator-based neutrino oscillation experiments. Previous extractions of FA from neutrino-deuteron scattering data rely on a dipole shape assumption that introduces an unquantified error. A new analysis of world data for neutrino-deuteron scattering is performed using a model-independent, and systematically improvable, representation of FA. A complete error budget for the nucleon isovector axial radius leads to rA2=0.46(22) fm2, with a much larger uncertainty than determined in the original analyses. The quasielastic neutrino-neutron cross section is determined as σ(νμn→μ-p)|Eν=1 GeV=10.1(0.9)×10-39 cm2. The propagation of nucleon-level constraints and uncertainties to nuclear cross sections is illustrated using MINERvA data and the GENIE event generator. These techniques can be readily extended to other amplitudes and processes

Constraints on new physics with (anti)neutrino-nucleon scattering data

New physics contributions to the (anti)neutrino-nucleon elastic scattering process can be constrained by precision measurements, with controlled Standard Model uncertainties. In a large class of new physics models, interactions involving charged leptons of different flavor can be related, and the large muon flavor component of accelerator neutrino beams can mitigate the lepton mass suppression that occurs in other low-energy measurements. We employ the recent high-statistics measurement of the cross section for ν¯μp→μ+n scattering on the hydrogen atom by MINERvA to place new confidence intervals on tensor and scalar neutrino-nucleon interactions: ReCT=−1−13+14×10−4, |ImCT|≤1.3×10−3, and |ImCS|=45−19+13×10−3. These results represent a reduction in uncertainty by a factor of 2.1, 3.1, and 1.2, respectively, compared to existing constraints from precision beta decay

Deuterium target data for precision neutrino-nucleus cross sections

Amplitudes derived from scattering data on elementary targets are basic inputs to neutrino-nucleus cross section predictions. A prominent example is the isovector axial nucleon form factor, $F_A(q^2)$, which controls charged current signal processes at accelerator-based neutrino oscillation experiments. Previous extractions of $F_A$ from neutrino-deuteron scattering data rely on a dipole shape assumption that introduces an unquantified error. A new analysis of world data for neutrino-deuteron scattering is performed using a model-independent, and systematically improvable, representation of $F_A$. A complete error budget for the nucleon isovector axial radius leads to $r_A^2=0.46(22) \,{\rm fm}^2$, with a much larger uncertainty than determined in the original analyses. The quasielastic neutrino-neutron cross section is determined as $\sigma(\nu_\mu n \to \mu^- p)\big|_{E_\nu =1\,{\rm GeV}} = 10.1(0.9) \times 10^{-39}{\rm cm}^2$. The propagation of nucleon-level constraints and uncertainties to nuclear cross sections is illustrated using MINERvA data and the GENIE event generator. These techniques can be readily extended to other amplitudes and processes.Comment: 17 pages, 9 figures. v2: Supplementary data included, minor typos corrected. v3: replaced with published versio

Deep Underground Neutrino Experiment (DUNE), Far Detector Technical Design Report, Volume I Introduction to DUNE

International audienceThe preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay—these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. The Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. This TDR is intended to justify the technical choices for the far detector that flow down from the high-level physics goals through requirements at all levels of the Project. Volume I contains an executive summary that introduces the DUNE science program, the far detector and the strategy for its modular designs, and the organization and management of the Project. The remainder of Volume I provides more detail on the science program that drives the choice of detector technologies and on the technologies themselves. It also introduces the designs for the DUNE near detector and the DUNE computing model, for which DUNE is planning design reports. Volume II of this TDR describes DUNE's physics program in detail. Volume III describes the technical coordination required for the far detector design, construction, installation, and integration, and its organizational structure. Volume IV describes the single-phase far detector technology. A planned Volume V will describe the dual-phase technology