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We present an analysis of the hyperon {Lambda}(1405) for p+p reactions at 3.5 GeV kinetic beam energy. The data were taken with the High Acceptance Di-Electron Spectrometer (HADES). A {Lambda}(1405) signal could be reconstructed in both charged decay channels ({Lambda}(1405){yields}{Sigma}{sup {+-}}{pi}{sup {+-}}).
We present an experimental study of {Lambda}(1405) via the in-flight (K{sup -},n) reaction on the deuteron target (J-PARC E31). We will measure all {Sigma}{sup +}{pi}{sup -}, {Sigma}{sup -}{pi}{sup +} and {Sigma}{sup 0}{pi}{sup 0} final states so that the isospin structure of the produced hyperon resonance state can be decomposed. In this report, we present an overview of the experiment and preparation status.
We propose a possible way to probe the interactions of kaon- and antikaon-nucleus by measuring K{sup +}K{sup -} pairs decayed from {phi}(1020) meson in a nuclear target. The K{sup +}K{sup -} pairs emerged from nuclei can be affected by hadronic potentials and the difference of kaon- and antikaon-nucleus potential maybe modify invariant masses of K{sup +}K{sup -} decayed from {phi} mesons. The {phi} mesons can be produced with a lead target for the energy region 1.5{approx}2.4 GeV at LEPS facility in Super Photon Ring 8-GeV (Spring-8). By comparing results of Monte Carlo calculation with experimental data, we can probe kaon-, and antikaon-nucleus potential.
Elastic {pi}N scattering and the reaction {pi}{sup +}p{yields}K{sup +}{Sigma}{sup +} are described simultaneously in a unitary coupled-channels approach which respects analyticity. SU(3) flavor symmetry is used to relate the t- and u- channel exchanges that drive the meson-baryon interaction in the different channels. Angular distributions, polarizations, and spin-rotation parameters are compared with available experimental data. The pole structure of the amplitudes is extracted from the analytic continuation.
No abstract prepared.
The neutrino oscillation phenomena in solar, atmospheric and accelerator based experiments have been solidly established during the last decade, recent experiments are aiming at more precise measurements which requires better understanding of the interaction of neutrinos with matter. The International Workshop on Neutrino-Nucleus Interactions in the Few-GeV region (NUINT) is a series of workshops concentrating on low-energy (few GeV), neutrino-nucleus interactions. The goal of this series is to bring theorists and experimentalists from the nuclear and high-energy communities together to address the many challenges to understanding these complex interactions. NUINT workshop series was initiated in KEK (Japan) ten years ago with the goals of understanding the neutrino interactions and its applications to accelerator based and atmospheric neutrino oscillation experiments. An overview of the situation after the last Nuint workshop is discussed in this paper.
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.
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.
A non-technical overview of charge current quasi-elastic neutrino interaction is presented. Many body computations of multinucleon ejection which is proposed to explain recent large axial mass measurements are discussed. A few comments on recent experimental results reported at NuInt11 workshop are included.
The T2K (Tokai-to-Kamioka) experiment is a long-baseline neutrino oscillation experiment, currently operating in Japan, aiming at measuring the {theta}{sub 13} mixing angle. It uses an intense off-axis beam of mainly muon neutrinos incident on the Super-Kamiokande detector. The off-axis near detector complex, ND280, can be used to perform charge current quasi-elastic (CCQE) measurements, that define the flux normalization and predict the unoscillated spectrum. The strategy for studying {nu}{sub {mu}} CCQE interactions in the ND280 detector is described, together with the first inclusive charge current results from the first period of T2K operation.
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 MiniBooNE experiment has prepared an almost pure beam of muon-neutrinos over an energy range of a few-hundred MeV to a few GeV with a sample of roughly one-million neutrino interactions. Detailed cross-section measurements have been performed spanning 89% of the total neutrino-interaction rate. Specifically, three single-pion production mechanisms have been measured in detail. These measurements are important for a myriad of reasons: Neutral-current neutral-pion production is an important background for electron-neutrino appearance searches, Charged-current charged-pion production is the single largest background for quasi-elastic scattering and also provides the purest sample of events at these energies, and charge-current neutral-pion production provides a pure measure of incoherent pion production. Each of these processes required custom event reconstructions due to the particulars of the final-state particles. In addition, the sample selections and analyses will be discussed in detail. Many single-pion cross-section measurements, and their possible implications will be presented.
We report measurements of neutrino induced pion production processes on carbon target with an average energy of {approx}0.8 GeV by SciBooNE experiment at Fermilab. These measurements are important inputs for current and future accelerator-based neutrino oscillation experiments in the interpretation of neutrino oscillation signals.
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.
Coherent pion production induced by neutrinos has received special attention as a potential background that may limit the sensitivity of neutrino oscillation measurements. On the other hand it depends on the poorly known weak hadronic current and on details of pion dynamics in nuclei. Different theoretical approaches developed to describe this reaction are reviewed. The assumptions, approximations, strong points and range of applicability of different models are discussed paying attention to the open questions.
I explain the Sato-Lee (SL) model and its extension to the neutrino-induced pion production off the nucleon. Then I discuss applications of the SL model to incoherent and coherent pion productions in the neutrino-nucleus scattering. I mention a further extension of this approach with a dynamical coupled-channels model developed in Excited Baryon Analysis Center of JLab.
The weak kaon production off the nucleon induced by neutrinos and antineutrinos is studied at low and intermediate energies of interest for some ongoing and future neutrino oscillation experiments. We develop a microscopical model based on the SU(3) chiral Lagrangians. The studied mechanisms are the main source of kaon production for neutrino energies up to 2 GeV for the various channels and the cross sections are large enough to be amenable to be measured by experiments such as Minerva, T2K and NOvA.
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.