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We investigate one pion production processes within the Giessen Boltzmann-Uehling-Uhlenbeck (GiBUU) coupled channel transport model. Our calculations for integrated and differential cross sections for realistic experimental neutrino fluxes are compared to the data recently provided by the MiniBooNE collaboration.
The status of the ArgoNeuT experiment's neutrino reconstruction software and analysis is presented. A number of physics measurement possibilities with ArgoNeuT are also discussed.
We study electroweak processes in complex nuclei within the framework of self-consistent mean field theories including pairing and RPA correlations. We review the adiabatic time dependent Hartree-Fock (HF) theory and its ability to simultaneously handle large and small amplitude modes. We apply the formalism to the study of single and double beta decay as normal modes of the system, allowing for collective deformation, using Skyrme density-dependent two-body interactions. We also apply the formalism to the study of parity-violating electron scattering. We highlight nuclear structure issues that are crucial for the correct analysis of these processes, namely neutron densities and spectroscopic factors, whose proper knowledge and interpretation in stable nuclei is required to get reliable predictions on exotic nuclei.
In this paper, we present a measurement of the rate of correlated neutron captures in the WATCHBOY detector, deployed at a depth of approximately 390 meters water equivalent (m.w.e.) in the Kimballton Underground Research Facility (KURF). WATCHBOY consists of a cylindrical 2 ton water target doped with 0.1% gadolinium, surrounded by a 40 ton undoped water hermetic shield. We present a comparison of our results with the expected rate of correlated neutron captures arising from high-energy neutrons incident on the outside of the WATCHBOY shield, predicted by a hybrid FLUKA/GEANT4-based simulation. The incident neutron energy distribution used in the simulation was measured by a fast neutron spectrometer, the 1.8-ton Multiplicity and Recoil Spectrometer (MARS) detector, at the same depth. We nd that the measured detection rate of two correlated neutrons is consistent with that predicted by simulation. The result lends additional confidence in the detection technique used by MARS, and therefore in the MARS spectra as measured at three different depths. Confirmation of the fast neutron flux and spectrum is important as it helps validate the scaling models used to predict the fast neutron fluxes at different overburdens.
In this work, inclusive electron scattering from nuclear targets has been measured to extract the nuclear dependence of the inelastic cross section in Hall C at the Thomas Jefferson National Accelerator facility. Results are presented for 2 H, 3 He, 4 He, 9 B, 12 C, 63 Cu and 197 Au at an incident electron beam energy of 5.77 GeV for a range of momentum transfer from Q 2 = 2 to 7 (GeV/c) 2 . These data improve the precision of the existing measurements of the EMC effect in the nuclear targets at large x, and allow for more detailed examinations of the A dependence of the EMC effect.
The neutron structure function, F 2n , has historically been extracted from measurements of the deuteron structure function, which is limited by our understanding of the nuclear effects on the bound proton and neutron. The MARATHON Collaboration recently extracted F 2n from the comparison of 3 H and 3 He targets, where the nuclear effects are larger but nearly identical, yielding a precise extraction of F 2n /F 2p . Here, to ensure that this comparison is not biased by the specific model of nuclear effects used by MARATHON, we examine a range of models of the nuclear effects to obtain a more conservative, but more model-independent, extraction of F 2n /F 2p for comparison with deuteron extractions. Even with this approach, the results are precise enough to compare to deuteron extractions, providing new constraints on the nuclear effects in the deuteron and indicating the need for larger nuclear corrections than those included in most models.
We measured the nuclear dependence of the di-pion azimuthal correlation function in deepinelastic scattering (DIS) using the CEBAF Large Acceptance Spectrometer (CLAS) and a 5 GeV electron beam. As the nuclear-target size increases, transitioning from deuterium to carbon, iron, and lead, the correlation function broadens monotonically. Its shape exhibits a significant dependence on kinematics, including the transverse momentum of the pions and the difference in their rapidity. None of the various Monte-Carlo event generators we evaluated could fully replicate the observed correlation functions and nuclear effects throughout the entire phase space. As the first study of its kind in DIS experiments, this research provides an important baseline for enhancing our understanding of the interplay between the nuclear medium and the hadronization process in these reactions.
Preliminary results on semi-inclusive charged pion production in eA collisions at E{sub beam} = 5 GeV/c{sup 2} are presented. The data were collected using the CLAS detector, which is a multipurpose, large acceptance, magnetic spectrometer located in Hall B at the Thomas Jefferson National Accelerator Facility. Distributions in W, Q{sup 2}, p{sub {pi}}, and {theta}{sub {pi}} are shown for data produced using deuterium and carbon targets. Preliminary comparisons with data simulated using the GENIE generator are made. The motivation for this work is to provide distributions useful for tuning the hadronic production models used in extracting results from current and next-generation neutrino oscillation experiments.
We calculate cross sections for the neutral current induced neutrino/antineutrino reaction from {sup 208}Pb target and applied it to study Supernova neutrino event rates. The calculations are done in local density approximation taking into account Pauli blocking, Fermi motion effects and renormalization of weak transition strengths in the nuclear medium. The numerical results for the neutrino nucleus total cross sections have been averaged over the various Supernova neutrino/antineutrino fluxes available in literature.
The extraction of neutrino oscillation parameters requires the determination of the neutrino energy from observations of the hadronic final state. Here we discuss the difficulties connected with this energy reconstruction for the ongoing experiments MiniBooNE and T2K. We point out that a lower limit to the uncertainty in the reconstructed energy from Fermi motion alone amounts to about 15%. The entanglement of very different elementary processes, in this case quasielastic scattering and pion production, in the actual observables leads to considerably larger errors. We discuss the sensitivity of the energy reconstruction to detection techniques and experimental acceptances. We also calculate the misidentification cross section for electron appearance in the T2K experiment due to neutral pion production.
We calculate the neutrino scattering and absorption on the hot and dense neutron-star matter with hyperons under the strong magnetic field using perturbative approach. We find that the absorption cross-sections show the remarkable angular dependence: its strength is reduced in the direction parallel to the magnetic field and enhanced in the opposite direction. This variation becomes about 2.2% when the magnetic field is about 2x10{sup 17} G.
Neutrino reactions recorded by the MINOS Near Detector in exposures totalling 2.8x10{sup 20} protons-on-target were searched for single, highly-forward {pi}{sup 0} mesons produced by coherent neutral current interactions {nu}{sub {mu}}+A{yields}{nu}{sub {mu}}+A+{pi}{sup 0}. Events having topologies consistent with single electromagnetic showers were isolated. Contributions from neutrino-induced backgrounds are determined using a data-driven fit of Monte Carlo distributions over sideband regions. The fit is used to project the background levels into signal regions. An excess of events above the best-fit background is observed for shower topologies of few GeV energies and at very forward angles. The partial cross section for NC({pi}{sup 0}) coherent scattering yielding E{sub vis}({pi}{sup 0})>1.0 GeV averaged over incident neutrino energies 2.4{<=}E{sub {nu}{<=}9}.0 GeV is (31.6{+-}10.5)x10{sup -40} cm{sup 2}/nucleus. Total cross sections for coherent scattering from nuclei of average nucleon number A{sub eff} = 48 and for iron (A = 56) nuclei are estimated for <E{sub {nu}>} = 4.9 GeV.
Determination of the quasi‐elastic scattering cross‐section over a broad range of neutrino energies, nuclear targets and Q2 is a primary goal of the MINERvA experiment. We present preliminary comparisons of data and simulation in a sample rich in ν̄μp→μ+n events from approximately one eighth of the total ν̄ events collected by MINERvA to date. We discuss future plans for quasi‐elastic analyses in MINERvA.
The MINOS experiment has the world's largest data set of neutrino interactions in the 1-10 GeV energy range. In addition, the data are neutrino interactions on iron, allowing us to explore the nuclear effects on neutrino scattering. We present two improvements to the MINOS charged current quasi-elastic analysis presented at NuInt 2009: a background correction function extracted from two resonance enhanced selections, and an improved fit procedure that includes event samples selected by looking for the recoil proton.
The PEANUT experiment was designed to study neutrino interactions in the few GeV range using the NuMi beam at Fermilab. The detector uses a hybrid technique, being made of nuclear emulsions and scintillator trackers. Emulsion films act as a tracking device and they are interleaved with lead plates used as neutrino target. The detector is designed to reconstruct the topology of neutrino interactions at the single particle level. We present here the full reconstruction and analysis of a sample of 147 neutrino interactions occurred in the PEANUT detector and the measurement of the quasi-elastic, resonance and deep-inelastic contributions to the total charged current cross-section. This technique could be applied for the beam monitoring for future neutrino facilities.
We report measurements of charged current inclusive and quasielastic interactions of muon neutrinos on carbon with an average energy of 0.8 GeV by SciBooNE experiment at Fermilab. These two results are complementary to understand the neutrino-nuclear interaction in the few-GeV region with effects of final state interactions.
The GiBUU model, which implements all reaction channels relevant at medium neutrino energy, is used to investigate the neutrino and antineutrino scattering on iron. Results for integrated cross sections are compared with NOMAD and MINOS data. It is shown, that final state interaction can noticeably change the spectra of the outgoing hadrons. Predictions for the Miner{nu}a experiment are made for pion spectra, averaged over NuMI neutrino and antineutrino fluxes.
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