1,271 research outputs found
The ANTARES project
The ANTARES deep-sea neutrino telescope will be located at a depth of 2400 m
in the Mediterranean Sea. Deployment of the detector will commence this Autumn
and is expected to be completed by the end of 2004. With a surface area of the
order of 0.1 km^2 it will be one of the largest European detectors. The aim of
neutrino telescopes is to detect high-energy neutrinos from astrophysical
sources whilst also providing information on the early Universe. Successful
operation of ANTARES in a deep sea environment constitutes an important
milestone towards the ultimate goal of the construction of an underwater
neutrino telescope at the cubic-kilometre scale. The sky coverage of
astrophysical sources offered by a Mediterranean neutrino telescope is
complementary to any similar device at the South Pole. The current status of
the project is discussed and the expected performance of the detector is
described in the context of the scientific programme of the project which
comprises astrophysical studies, dark matter searches and neutrino
oscillations.Comment: Submitted to ICHEP02 Conference, 31st Int. Conf. on High Energy
Physics, 24-31 July 2002, Amsterdam. LaTeX, 10 pages, 9 figure
Testing Quantum Gravity via Cosmogenic Neutrino Oscillations
Implications of some proposed theories of quantum gravity for neutrino flavor
oscillations are explored within the context of modified dispersion relations
of special relativity. In particular, approximate expressions for
Planck-scale-induced deviations from the standard oscillation length are
obtained as functions of neutrino mass, energy, and propagation distance.
Grounding on these expressions, it is pointed out that, in general, even those
deviations that are suppressed by the second power of the Planck energy may be
observable for ultra-high-energy neutrinos, provided they originate at
cosmological distances. In fact, for neutrinos in the highest energy range of
EeV to ZeV, deviations that are suppressed by as much as the seventh power of
the Planck energy may become observable. Accordingly, realistic possibilities
of experimentally verifying these deviations by means of the next generation
neutrino detectors--such as IceCube and ANITA--are investigated.Comment: 8 pages, RevTeX4; Essentially the published versio
Status report of the ANTARES project
The ANTARES project aims at the construction of an underwater neutrino
telescope at the scale of 0.1 km^2 2400 m deep in the Mediterranean Sea. After
a 4-year R&D program, the ANTARES project has entered the construction phase
which will be concluded by the end of 2004. The current status of the project
is reported.Comment: 3 pages, 2 figures. to appear in Proc. of TAUP2001 conference,
Laboratori Nazionali del Gran Sasso, Sept. 200
An exploration of hadronic interactions in blazars using IceCube
Context: Hadronic models, involving matter (proton or nuclei) acceleration in
blazar jets, imply high energy photon and neutrino emissions due to
interactions of high-energy protons with matter and/or radiation in the source
environment. Aims: This paper shows that the sensitivity of the IceCube
neutrino telescope in its 40-string configuration (IC-40) is already at the
level of constraining the parameter space of purely hadronic scenarios of
activity of blazars. Methods: Assuming that the entire source power originates
from hadronic interactions, and assuming that the models describe the data, we
estimate the expected neutrino flux from blazars based on the observed
gamma-ray flux by Fermi, simultaneously with IC-40 observations. We consider
two cases separately to keep the number of constrainable parameters at an
acceptable level: proton-proton or proton-gamma interactions are dominant.
Comparing the IC-40 sensitivity to the neutrino flux expected from some of the
brightest blazars, we constrain model parameters characterizing the parent
high-energy proton spectrum. Results: We find that when pp interactions
dominate, some constraints on the primary proton spectrum can be imposed. For
instance, for the tightest constrained source 3C 454.3, the very high energy
part of the spectra of blazars is constrained to be harder than E^-2 with
cut-off energies in the range of Ecut >10^18 eV. When interactions of
high-energy protons on soft photon fields dominate, we can find similarly tight
constraints on the proton spectrum parameters. [abridged]Comment: accepted for publication in A&
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