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Nuclear physics inputs needed for geo-neutrino studies  [PDF]
G. Bellini,G. Fiorentini,A. Ianni,M. Lissia,F. Mantovani,O. Smirnov
Physics , 2007, DOI: 10.1088/1742-6596/120/5/052007
Abstract: Geo-neutrino studies are based on theoretical estimates of geo-neutrino spectra. We propose a method for a direct measurement of the energy distribution of antineutrinos from decays of long-lived radioactive isotopes.
Dynamical r-process studies within the neutrino-driven wind scenario and its sensitivity to the nuclear physics input  [PDF]
A. Arcones,G. Martinez-Pinedo
Physics , 2010, DOI: 10.1103/PhysRevC.83.045809
Abstract: We use results from long-time core-collapse supernovae simulations to investigate the impact of the late time evolution of the ejecta and of the nuclear physics input on the calculated r-process abundances. Based on the latest hydrodynamical simulations, heavy r-process elements cannot be synthesized in the neutrino-driven winds that follow the supernova explosion. However, by artificially increasing the wind entropy, elements up to A=195 can be made. In this way one can reproduce the typical behavior of high-entropy ejecta where the r-process is expected to occur. We identify which nuclear physics input is more important depending on the dynamical evolution of the ejecta. When the evolution proceeds at high temperatures (hot r-process), an (n,g)-(g,n) equilibrium is reached. While at low temperature (cold r-process) there is a competition between neutron captures and beta decays. In the first phase of the r-process, while enough neutrons are available, the most relevant nuclear physics input are the nuclear masses for the hot r-process and the neutron capture and beta-decay rates for the cold r-process. At the end of this phase, the abundances follow a steady beta flow for the hot r-process and a steady flow of neutron captures and beta decays for the cold r-process. After neutrons are almost exhausted, matter decays to stability and our results show that in both cases neutron captures are key for determining the final abundances, the position of the r-process peaks, and the formation of the rare-earth peak. In all the cases studied, we find that the freeze out occurs in a timescale of several seconds.
Neutrino Interactions Importance for Nuclear Physics  [PDF]
J. E. Amaro,C. Maieron,M. Valverde,J. Nieves,M. B. Barbaro,J. A. Caballero,T. W. Donnelly,J. M. Udias
Physics , 2009, DOI: 10.1063/1.3274166
Abstract: We review the general interplay between Nuclear Physics and neutrino-nucleus cross sections at intermediate and high energies. The effects of different reaction mechanisms over the neutrino observables are illustrated with examples in calculations using several nuclear models and ingredients.
The Nuclear Physics of Solar and Supernova Neutrino Detection  [PDF]
W. C. Haxton
Physics , 1999,
Abstract: This talk provides a basic introduction for students interested in the responses of detectors to solar, supernova, and other low-energy neutrino sources. Some of the nuclear physics is then applied in a discussion of nucleosynthesis within a Type II supernova, including the r-process and the neutrino process.
Nuclear Physics Neutrino PreTown Meeting: Summary and Recommendations  [PDF]
W. C. Haxton,John Bahcall,A. Baha Balantekin,Stuart Freedman,Kevin Lesko,Hamish Robertson,Bob Lanou,George Fuller,Ken Lande,Tony Mezzacappa,Frank Avignone,Bill Louis,Petr Vogel,Todd Haines,John Wilkerson
Physics , 2000,
Abstract: In preparation for the nuclear physics Long Range Plan exercise, a group of 104 neutrino physicists met in Seattle September 21-23 to discuss both the present state of the field and the new opportunities of the next decade. This report summarizes the conclusions of that meeting and presents its recommendations. Further information is available at the workshop's web site. This report will be further reviewed at the upcoming Oakland Town Meeting.
Neutrino-Oxygen interactions: role of nuclear physics in the atmospheric neutrino anomaly  [PDF]
J. Marteau,J. Delorme,M. Ericson
Physics , 1999,
Abstract: The apparent anomaly in the ratio of muon to electron atmospheric neutrinos first observed by Kamiokande and IMB has been confirmed by Super-Kamiokande and Soudan-2. The experimental analysis, including the asymmetry in the zenithal distributions of the $ \mu-\mathrm{type} $ events in Super-Kamiokande gives a strong support to the neutrino oscillation hypothesis to solve the anomaly. In this work we are interested by the role of nuclear physics in the neutrino-oxygen reactions used to detect the atmospheric neutrinos. We point out that multi-nucleon excitations of np-nh type and that nuclear correlations could modify an experimental analysis \`a la Super-Kamiokande because they lead to a substantial enhancement of the number of 1 \v{C}erenkov ring retained events.
Explosive nucleosynthesis: nuclear physics impact using neutrino-driven wind simulations  [PDF]
A. Arcones,G. Martinez-Pinedo
Physics , 2010,
Abstract: We present nucleosynthesis studies based on hydrodynamical simulations of core-collapse supernovae and their subsequent neutrino-driven winds. Although the conditions found in these simulations are not suitable for the rapid neutron capture (r-process) to produce elements heavier than A$\sim$130, this can be solved by artificially increasing the wind entropy. In this way one can mimic the general behavior of an ejecta where the r-process occurs. We study the impact of the long-time dynamical evolution and of the nuclear physics input on the final abundances and show that different nuclear mass models lead to significant variations in the abundances. These differences can be linked to the behavior of nuclear masses far from stability. In addition, we have analyzed in detail the effect of neutron capture and beta-delayed neutron emission when matter decays back to stability. In all our studied cases, freeze out effects are larger than previously estimated and produce substantial changes in the post freeze out abundances.
Dark Matter Studies Entrain Nuclear Physics  [PDF]
Susan Gardner,George Fuller
Physics , 2013, DOI: 10.1016/j.ppnp.2013.03.001
Abstract: We review theoretically well-motivated dark-matter candidates, and pathways to their discovery, in the light of recent results from collider physics, astrophysics, and cosmology. Taken in aggregate, these encourage broader thinking in regards to possible dark-matter candidates --- dark-matter need not be made of "WIMPs," i.e., elementary particles with weak-scale masses and interactions. Facilities dedicated to nuclear physics are well-poised to investigate certain non-WIMP models. In parallel to this, developments in observational cosmology permit probes of the relativistic energy density at early epochs and thus provide new ways to constrain dark-matter models, provided nuclear physics inputs are sufficiently well-known. The emerging confluence of accelerator, astrophysical, and cosmological constraints permit searches for dark-matter candidates in a greater range of masses and interaction strengths than heretofore possible.
Evaluating nuclear physics inputs in core-collapse supernova models  [PDF]
Eric J. Lentz,W. Raphael Hix,Mark L. Baird,O. E. Bronson Messer,Anthony Mezzacappa
Physics , 2010,
Abstract: Core-collapse supernova models depend on the details of the nuclear and weak interaction physics inputs just as they depend on the details of the macroscopic physics (transport, hydrodynamics, etc.), numerical methods, and progenitors. We present preliminary results from our ongoing comparison studies of nuclear and weak interaction physics inputs to core collapse supernova models using the spherically-symmetric, general relativistic, neutrino radiation hydrodynamics code Agile-Boltztran. We focus on comparisons of the effects of the nuclear EoS and the effects of improving the opacities, particularly neutrino--nucleon interactions.
Neutrino-Long-Baseline Experiments and Nuclear Physics  [PDF]
Ulrich Mosel,Olga Lalakulich
Physics , 2012,
Abstract: Neutrino long-baseline experiments nowadays all use nuclear targets. The extraction of neutrino oscillation parameters from such experiments requires a good understanding of the interaction of neutrinos with nuclei. In this talk we discuss results on quasielastic scattering and pion production which are the relevant processes in the neutrino energy regime around 1 GeV. We also discuss implications of the reaction mechanisms for the reconstruction of the neutrino energy which is not known a priori.
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