7,217 research outputs found
Neutrino-nucleus interactions in the T2K experiment
We present a study of neutrino-nucleus interactions at the T2K experiment
based on the GiBUU transport model. The aim of T2K is to measure
appearance and , but it will also be able to do a precise
measurement of disappearance. The former requires a good
understanding of production while the latter is closely connected with
a good understanding of quasielastic scattering. For both processes we
investigate the influence of nuclear effects and particular final-state
interactions on the expected event rates taking into account the T2K detector
setup.Comment: v3: matches version to be published in Phys. Rev.
Neutral current neutrino-nucleus interactions at intermediate energies
We have extended our model for charged current neutrino-nucleus interactions
to neutral current reactions. For the elementary neutrino-nucleon interaction,
we take into account quasielastic scattering, Delta excitation and the
excitation of the resonances in the second resonance region. Our model for the
neutrino-nucleus collisions includes in-medium effects such as Fermi motion,
Pauli blocking, nuclear binding, and final-state interactions. They are
implemented by means of the Giessen Boltzmann-Uehling-Uhlenbeck (GiBUU)
coupled-channel transport model. This allows us to study exclusive channels,
namely pion production and nucleon knockout. We find that final-state
interactions modify considerably the distributions through rescattering,
charge-exchange and absorption. Side-feeding induced by charge-exchange
scattering is important in both cases. In the case of pions, there is a strong
absorption associated with the in-medium pionless decay modes of the Delta,
while nucleon knockout exhibits a considerable enhancement of low energy
nucleons due to rescattering. At neutrino energies above 1 GeV, we also obtain
that the contribution to nucleon knockout from Delta excitation is comparable
to that from quasielastic scattering.Comment: 16 pages, 10 figures; v2: version to be published in Phys. Rev. C,
comparison with results of Paschos et al. remove
Neutrino interactions with nucleons and nuclei at intermediate energies
We investigate neutrino-nucleus collisions at intermediate energies
incorporating quasielastic scattering and Delta(1232) excitation as elementary
processes, together with Fermi motion, Pauli blocking and mean-field potentials
in the nuclear medium. A full coupled-channel treatment of final state
interactions is achieved with a semiclassical BUU transport model. Results for
inclusive reactions and nucleon knockout are presented.Comment: Proceedings of PANIC'05, 3 pages, 3 figure
Pion production in the MiniBooNE
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.Comment: Talk at NuInt11, Dehradun, India, March 201
The influence of the nuclear medium on inclusive electron and neutrino scattering off nuclei
We present a model for inclusive electron and neutrino scattering off nuclei
paying special attention to the influence of in-medium effects on the
quasi-elastic scattering and pion-production mechanisms. Our results for
electron scattering off Oxygen are compared to experimental data at beam
energies ranging from 0.7-1.5 GeV. The good description of electron scattering
serves as a benchmark for neutrino scattering.Comment: 6 pages, 3 figure
Dynamic Variation in Sexual Contact Rates in a Cohort of HIV-Negative Gay Men
Human immunodeficiency virus (HIV) transmission models that include variability in sexual behavior over time have shown increased incidence, prevalence, and acute-state transmission rates for a given population risk profile. This raises the question of whether dynamic variation in individual sexual behavior is a real phenomenon that can be observed and measured. To study this dynamic variation, we developed a model incorporating heterogeneity in both between-person and within-person sexual contact patterns. Using novel methodology that we call iterated filtering for longitudinal data, we fitted this model by maximum likelihood to longitudinal survey data from the Centers for Disease Control and Prevention's Collaborative HIV Seroincidence Study (1992–1995). We found evidence for individual heterogeneity in sexual behavior over time. We simulated an epidemic process and found that inclusion of empirically measured levels of dynamic variation in individual-level sexual behavior brought the theoretical predictions of HIV incidence into closer alignment with reality given the measured per-act probabilities of transmission. The methods developed here provide a framework for quantifying variation in sexual behaviors that helps in understanding the HIV epidemic among gay men
In-Medium Effects in Photo- and Neutrino-Induced Reactions on Nuclei
In this talk various aspects of in-medium behavior of hadrons are discussed
with an emphasis on observable effects. It is stressed that final state
interactions can have a major effect on observables and thus have to be
considered as part of the theory. This is demonstrated with examples from
photo-nucleus and neutrino-nucleus interactions.Comment: Invited talk, given by U. Mosel, at MESON2006, 9-th International
Workshop on Meson Production, Interaction and Decay, June 9-13, 2006, Cracow,
Polan
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