PaperPanorama
FAQ

Nuclear Theory·nucl-th

Friday·March 11, 2016

9 papers—6 primary·3 cross-listed

All9Primary6Cross-lists3
  1. 07

    [Submitted on 9 Mar 2016] (cross-list from hep-ph)

    Deuterium target data for precision neutrino-nucleus cross sections

    Aaron S. Meyer🇺🇸 · Minerba Betancourt🇺🇸 · Richard Gran🇺🇸 · Richard J. Hill🇺🇸

    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, , which controls charged current signal processes at accelerator-based neutrino oscillation experiments. Previous extractions of 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 . A complete error budget for the nucleon isovector axial radius leads to , with a much larger uncertainty than determined in the original analyses. The quasielastic neutrino-neutron cross section is determined as . 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.

    Comments:
    17 pages, 9 figures. v2: Supplementary data included, minor typos corrected. v3: replaced with published version
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
    arXiv:
    1603.03048 [pdf]
    PRD(2016)·242 citations
  2. 08

    [Submitted on 10 Mar 2016] (cross-list from astro-ph.CO)

    Low-lying Resonances and Relativistic Screening in Big Bang Nucleosynthesis

    Michael A. Famiano🇺🇸 · A. Baha Balantekin🇺🇸 · Toshitaka Kajino🇯🇵

    We explore effects of the screening due to the relativistic electron-positron plasma and presence of resonances in the secondary reactions leading to A=7 nuclei during the Big Bang Nucleosynthesis. In particular, we investigate and examine possible low-lying resonances in the Be(He, )C reaction and examine the resultant destruction of Be for various resonance locations and strengths. While a resonance in the C compound nucleus is thought to have negligible effects we explore the possibility of an enhancement from plasma screening that may adjust the final Be abundance. We find the effects of relativistic screening and possible low-lying resonances to be relatively small in the standard Early Universe models.

    Comments:
    8 pages, 13 figures, Physical Review C (2016) (in press)
    Subjects:
    Cosmology and Nongalactic Astrophysics (astro-ph.CO); Nuclear Theory (nucl-th)
    arXiv:
    1603.03137 [pdf]
    PRC(2016)·20 citations
  3. 09

    [Submitted on 10 Mar 2016] (cross-list from hep-ph)

    Transient anomalous charge production in strong-field QCD

    N. Tanji🇩🇪 · N. Mueller🇩🇪 · J. Berges🇩🇪

    We investigate axial charge production in two-color QCD out of equilibrium. We compute the real-time evolution starting with spatially homogeneous strong gauge fields, while the fermions are in vacuum. The idealized class of initial conditions is motivated by glasma flux tubes in the context of heavy-ion collisions. We focus on axial charge production at early times, where important aspects of the anomalous dynamics can be derived analytically. This is compared to real-time lattice simulations. Quark production at early times leading to anomalous charge generation is investigated using Wilson fermions. Our results indicate that coherent gauge fields can transiently produce significant amounts of axial charge density, while part of the induced charges persist to be present even well beyond characteristic decoherence times. The comparisons to analytic results provide stringent tests of real-time representations of the axial anomaly on the lattice.

    Comments:
    12 pages, 10 figures; To appear in Phys. Rev. D
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
    arXiv:
    1603.03331 [pdf]
    PRD(2016)·26 citations

Affiliations

first authorsco-authorsvia INSPIRE