1,986 research outputs found
Potential for Supernova Neutrino Detection in MiniBooNE
The MiniBooNE detector at Fermilab is designed to search for oscillation appearance at and to make a
decisive test of the LSND signal. The main detector (inside a veto shield) is a
spherical volume containing 0.680 ktons of mineral oil. This inner volume,
viewed by 1280 phototubes, is primarily a \v{C}erenkov medium, as the
scintillation yield is low. The entire detector is under a 3 m earth
overburden. Though the detector is not optimized for low-energy (tens of MeV)
events, and the cosmic-ray muon rate is high (10 kHz), we show that MiniBooNE
can function as a useful supernova neutrino detector. Simple trigger-level cuts
can greatly reduce the backgrounds due to cosmic-ray muons. For a canonical
Galactic supernova at 10 kpc, about 190 supernova
events would be detected. By adding MiniBooNE to the international network of
supernova detectors, the possibility of a supernova being missed would be
reduced. Additionally, the paths of the supernova neutrinos through Earth will
be different for MiniBooNE and other detectors, thus allowing tests of
matter-affected mixing effects on the neutrino signal.Comment: Added references, version to appear in PR
New Limits on Dark Matter from Super-Kamiokande
The signals observed at the direct detection experiments DAMA, CoGeNT and
CRESST could be explained by light WIMPs with sizeable spin-independent cross
sections with nucleons. The capture and subsequent annihilation of such
particles in the sun would induce neutrino signals in the GeV range which may
be observed at Super-Kamiokande. We determine the rate of upward stopping muons
and fully contained events at Super-Kamiokande for various possible WIMP
annihilation channels. This allows us to provide strong constraints on the
cross section of WIMPs with nucleons. We find that the DAMA and CoGeNT signals
are inconsistent with standard thermal WIMPs annihilating dominantly into
neutrino or tau pairs. We also provide limits for spin-dependent WIMP nucleus
scattering for masses up to 80 GeV. These exclude the DAMA favored region if
WIMPs annihilate even subdominantly into neutrinos, taus, bottoms or charms.Comment: 19 pages, 4 figure
Enhanced signal of astrophysical tau neutrinos propagating through Earth
Earth absorbs \nue and \numu of energies above about 100 TeV. As is
well-known, although \nutau will also disappear through charged-current
interactions, the \nutau flux will be regenerated by prompt tau decays. We
show that this process also produces relatively large fluxes of secondary
\nube and \nubmu, greatly enhancing the detectability of the initial
\nutau. This is particularly important because at these energies \nutau is
a significant fraction of the expected astrophysical neutrino flux, and only a
tiny portion of the atmospheric neutrino flux.Comment: Four pages, two inline figure
PPPC 4 DM: A Poor Particle Physicist Cookbook for Neutrinos from DM annihilations in the Sun
We provide ingredients and recipes for computing neutrino signals of
TeV-scale Dark Matter annihilations in the Sun. For each annihilation channel
and DM mass we present the energy spectra of neutrinos at production,
including: state-of-the-art energy losses of primary particles in solar matter,
secondary neutrinos, electroweak radiation. We then present the spectra after
propagation to the Earth, including (vacuum and matter) flavor oscillations and
interactions in solar matter. We also provide a numerical computation of the
capture rate of DM particles in the Sun. These results are available in
numerical form.Comment: 27 pages, many figures. v2: a typo corrected in eq.(18). All results
are available at http://www.marcocirelli.net/PPPC4DMID.htm
Neutrino signals from electroweak bremsstrahlung in solar WIMP annihilation
Bremsstrahlung of and gauge bosons, or photons, can be an important
dark matter annihilation channel. In many popular models in which the
annihilation to a pair of light fermions is helicity suppressed, these
bremsstrahlung processes can lift the suppression and thus become the dominant
annihilation channels. The resulting dark matter annihilation products contain
a large, energetic, neutrino component. We consider solar WIMP annihilation in
the case where electroweak bremsstrahlung dominates, and calculate the
resulting neutrino spectra. The flux consists of primary neutrinos produced in
processes such as and , and secondary neutrinos produced via the decays of gauge
bosons and charged leptons. After dealing with the neutrino propagation and
flavour evolution in the Sun, we consider the prospects for detection in
neutrino experiments on Earth. By comparing our signal with that for
annihilation to , we show that the detection prospects for the
bremsstrahlung annihilation channel are favourable.Comment: 18 pages, 5 figures. Discussion expanded; matches published versio
Neutrino-induced Muon Fluxes from Neutralino Annihilations in the Sun and in the Earth
The flux of neutrino-induced muons at the surface of the Earth is calculated
from injection of neutralino annihilation products in the core of the Sun and
the Earth. An improved treatment of neutrino propagation through the Sun is
performed and the results are presented in an easy-to-use parameterization. For
an explicit supersymmetric model, an observable neutralino annihilation signal
is demonstrated.Comment: 4 pages, 2 figures (uuencoded compressed tar-files), uses espcrc2.st
High Energy Cosmic Neutrinos Astronomy: The ANTARES Project
Neutrinos may offer a unique opportunity to explore the far Universe at high
energy. The ANTARES collaboration aims at building a large undersea neutrino
detector able to observe astrophysical sources (AGNs, X-ray binary systems,
...) and to study particle physics topics (neutrino oscillation, ...). After
a description of the research opportunities of such a detector, a status report
of the experiment will be made.Comment: Talk given at the 19th Texas Symposium, Paris, December 199
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