789 research outputs found
Supernova neutrino oscillations: what do we understand?
We summarize our current understanding of the neutrino flavor conversions
inside a core collapse supernova, clarifying the important role played by the
"collective effects" in determining flavor conversion probabilities. The
potentially observable and spectra may help us identify
the neutrino mixing scenario, distinguish between primary flux models, and
learn more about the supernova explosion.Comment: 6 pages, 1 eps figure, jpconf.cls used. Talk given at TAUP 2009,
Rome, July 200
Dynamics of chiral oscillations - A comparative analysis with spin-flipping
Chiral oscillation as well as spin flipping effects correspond to quantum
phenomena of fundamental importance in the context of particle physics and, in
particular, of neutrino physics. From the point of view of first quantized
theories, we are specifically interested in appointing the differences between
chirality and helicity by obtaining their dynamic equations for a fermionic
Dirac-type particle (neutrino). We also identify both effects when the
non-minimal coupling with an external (electro)magnetic field in the neutrino
interacting Lagrangian is taken into account. We demonstrate that, however,
there is no constraint between chiral oscillations, when it takes place in
vacuum, and the process of spin flipping related to the helicity quantum
number, which does not take place in vacuum. To conclude, we show that the
origin of chiral oscillations (in vacuum) can be interpreted as position very
rapid oscillation projections onto the longitudinal direction of momentum.Comment: 14 pages, no figure
Searching for prompt signatures of nearby core-collapse supernovae by a joint analysis of neutrino and gravitational-wave data
We discuss the science motivations and prospects for a joint analysis of
gravitational-wave (GW) and low-energy neutrino data to search for prompt
signals from nearby supernovae (SNe). Both gravitational-wave and low-energy
neutrinos are expected to be produced in the innermost region of a
core-collapse supernova, and a search for coincident signals would probe the
processes which power a supernova explosion. It is estimated that the current
generation of neutrino and gravitational-wave detectors would be sensitive to
Galactic core-collapse supernovae, and would also be able to detect
electromagnetically dark SNe. A joint GW-neutrino search would enable
improvements to searches by way of lower detection thresholds, larger distance
range, better live-time coverage by a network of GW and neutrino detectors, and
increased significance of candidate detections. A close collaboration between
the GW and neutrino communities for such a search will thus go far toward
realizing a much sought-after astrophysics goal of detecting the next nearby
supernova.Comment: 10 pages, 3 figures. To appear in Class. Quantum Gra
Discovering the New Standard Model: Fundamental Symmetries and Neutrinos
This White Paper describes recent progress and future opportunities in the
area of fundamental symmetries and neutrinos.Comment: Report of the Fundamental Symmetries and Neutrinos Workshop, August
10-11, 2012, Chicago, I
Low energy neutrino scattering measurements at future Spallation Source facilities
In the future several Spallation Source facilities will be available
worldwide. Spallation Sources produce large amount of neutrinos from
decay-at-rest muons and thus can be well adapted to accommodate
state-of-the-art neutrino experiments. In this paper low energy neutrino
scattering experiments that can be performed at such facilities are reviewed.
Estimation of expected event rates are given for several nuclei, electrons and
protons at a detector located close to the source. A neutrino program at
Spallation Sources comprises neutrino-nucleus cross section measurements
relevant for neutrino and core-collapse supernova physics, electroweak tests
and lepton-flavor violation searches.Comment: 12 pages, 4 figures, 5 table
Hybrid method to resolve the neutrino mass hierarchy by supernova (anti)neutrino induced reactions
We introduce a hybrid method to determine the neutrino mass hierarchy by simultaneous measurements of responses of at least two detectors to antineutrino and neutrino fluxes from accretion and cooling phases of core-collapse supernovae. The (anti)neutrino-nucleus cross sections for 56Fe and 208Pb are calculated in the framework of the relativistic nuclear energy density functional and weak interaction Hamiltonian, while the cross sections for inelastic scattering on free protons p(vÂŻe,e+)n are obtained using heavy-baryon chiral perturbation theory. The modelling of (anti)neutrino fluxes emitted from a protoneutron star in a core-collapse supernova include collective and Mikheyev-Smirnov-Wolfenstein effects inside the exploding star. The particle emission rates from the elementary decay modes of the daughter nuclei are calculated for normal and inverted neutrino mass hierarchy. It is shown that simultaneous use of (anti)neutrino detectors with different target material allows to determine the neutrino mass hierarchy from the ratios of ve- and vÂŻe-induced particle emissions. This hybrid method favors neutrinos from the supernova cooling phase and the implementation of detectors with heavier target nuclei (208Pb) for the neutrino sector, while for antineutrinos the use of free protons in mineral oil or water is the appropriate choice.Peer reviewedFinal Accepted Versio
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