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At least 37 records · Page 2

New Results from MiniBooNE Charged-Current Quasi-Elastic Anti-Neutrino Data

MiniBooNE anti-neutrino charged-current quasi-elastic (CCQE) data is compared to model predictions. The main background of neutrino-induced events is examined first, where three independent techniques are employed. Results indicate the neutrino flux is consistent with a uniform reduction of {approx}20% relative to the largely uncertain prediction. After background subtraction, the Q{sup 2} shape of {nu}-bar{sub {mu}} CCQE events is consistent with the model parameter M{sub A} = 1.35 GeV determined from MiniBooNE {nu}{sub {mu}} CCQE data, while the normalization is {approx}20% high compared to the same prediction.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

NEUT Pion FSI

The pion final state interaction model in NEUT is described. Modifications and tuning of the model are validated against neutrino and non-neutrino (pion scattering and photoproduction) data. A method for evaluating the uncertainties in the model and propagation of systematic errors in a neutrino oscillation experiment is described, using T2K as a specific example.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Neutrino resonance production at very low momentum transfer

I look back at comparisons of CC neutrino resonance interaction data at very low Q{sup 2}, from seven experiments, compared to the predictions of current neutrino event generators. When compared to data, the generator models, primarily based on the model of Rein and Sehgal, overpredict the event rate at very low Q{sup 2} for samples that are enhanced in resonance {pi}{sup +} interactions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Nuclear quests for supernova dynamics and nucleosynthesis

Nuclear physics plays a crucial role in various aspects of core collapse supernovae. The collapse dynamics is strongly influenced by electron captures. Using modern many-body theory improved capture rates have been derived recently with the important result that the process is dominated by capture on nuclei until neutrino trapping is achieved. Following the core bounce the ejected matter is the site of interesting nucleosynthesis. The early ejecta are proton-rich and give rise to the recently discovered {nu}p-process. Later ejecta might be neutron-rich and can be one site of the r-process. The manuscript discusses recent progress in describing nuclear input relevant for the supernova dynamics and nucleosynthesis.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

2p2h or not 2p2h?

This paper summarizes the discussion about the role of two-particle-two-hole (2p2h) excitations in neutrino-nucleus interactions in the few-GeV region, held at NuInt11.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Using Neutrino Nucleus Interactions as a Probe of the Strong Interaction

Neutrino scattering experiments have been studying QCD for over 30 years. From the Gargamelle experiments in the early 70's, through the subsequent bubble chamber and electronic detector experiments in the 80's and 90's, neutrino scattering experiments have steadily accumulated increasing statistics and minimized their systematic errors. An example of the more recent studies of QCD with neutrinos is from the TeVatron neutrino beam--the NuTeV {nu}-Fe experiment. The problem the community faces in trying to study QCD with modern neutrino data is that there is no experimentally verified way to scale neutrino-nucleus (for example, Fe) results to the equivalent neutrino-nucleon values making it difficult to combine neutrino nucleus scattering data with charged-lepton nucleus and nucleon scattering data in QCD global fits to extract parton distribution functions. This is particularly crucial since there is now indications that nuclear effects in neutrino nucleus interactions are different than those measured in charged-lepton nucleus scattering. To better understand this situation, the MINER{nu}A neutrino-nucleus scattering experiment at Fermilab, a collaboration of elementary-particle and nuclear physicists, is systematically studying neutrino nuclear effects off of He, C, Fe and Pb for a more thorough A-dependent study of nuclear PDFs and these correction factors.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Highlights from NuInt11

We have seen significant advancement in our understanding of few-GeV neutrino-nucleus interactions since the time of the first NuInt workshop in 2001. Now ten years later, we reflect on our progress. Highlights from the NuInt11 workshop are presented along with some suggestions for future directions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Strange particle production at low and intermediate energies

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.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Experimental Measurement of Low Energy Neutrino Interactions

Neutrino interactions in the few to few tens of MeV range are of importance for several physics topics, including solar, supernova and reactor neutrinos, as well as future proposed oscillation and Standard Model test experiments. Although interaction cross-sections for some simple targets are well understood, very little experimental data exist for interactions with nuclei. This talk will discuss the motivation for measuring low energy neutrino interactions, the state of knowledge, and possible future strategies.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Neutrino Induced Pion Production at SciBooNE

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.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Neutral Current Elastic Interactions in MiniBooNE

Neutral Current Elastic (NCE) interactions in MiniBooNE are discussed. In the neutrino mode MiniBooNE reported: the flux averaged NCE differential cross section as a function of four-momentum transferred squared, an axial mass (M{sub A}) measurement, and a measurement of the strange quark spin content of the nucleon, {Delta}s. In the antineutrino mode we present the background-subtracted data which is compared with the Monte Carlo predictions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Cross-section Effects in the Super-Kamiokande Tau Appearance Analysis

In this talk, I explain the search for tau neutrino appearance in the atmospheric neutrino flux at Super-Kamiokande with a particular emphasis on the effect deep inelastic cross section uncertainties have on interpreting the result. In particular, I explain why the normalization of the DIS cross-section also needs to be treated as a parameter in the fit of tau normalization, and show how a neural net based on event parameters can separate various cross-section modes in the background sample.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

From Sitges to Dehra-Dun: a personal view of the needs and situation of neutrino nucleus interactions

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.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Higher twist contributions to the azimuthal asymmetries in semi-inclusive DIS

In this talk, I summarize the conclusions and results that we obtained in recent publications to calculate the higher twist contributions to the azimuthal asymmetries in semi-inclusive deep inelastic lepton-nucleon and/or lepton-nucleus scattering. We show that the collinear expansion can be extended to the semi-inclusive scattering process l+p{yields}l+q+X, where q represents the struck quark and corresponds to the current jet in experiments. We present the results for the differential cross section and the azimuthal asymmetries up to twist-4 and discuss the nuclear dependence.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Strategy for studying {nu}{sub {mu}} CCQE interactions in the T2K near detector

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.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Gamow-Teller Transitions Starting from T{sub z} = +3/2 Nucleus {sup 47}Ti

Gamow-Teller (GT) transitions are mediated by the {sigma}{tau} operator. Owing to its simplicity and also its spin-isospin nature, GT transitions play key roles in the studies of nuclear structure as well as astro-nuclear processes. In violent neutrino-induced reactions at the core-collapse stage of type II supernovae, Gamow-Teller (GT) transitions starting from stable as well as unstable pf-shell nuclei play important roles. We study GT transitions starting from {sup 47}Ti in a high-resolution ({sup 3}He,t) charge-exchange reactions at 0 deg. and at an intermediate incident energy of 140 MeV/nucleon at Research Center for Nuclear Physics (RCNP), Osaka. Individual GT transitions up to high excitations were observed. Assuming the isospin symmetry for the strengths of T{sub z} = {+-}3/2{yields}{+-}1/2 analogous GT transitions, we can deduce the detailed strength distribution starting from mirror unstable nucleus {sup 47}Mn.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗