1,106 research outputs found
MACRO and the atmospheric neutrino problem
After a brief presentation of the MACRO detector we discuss the updated data
on atmospheric muon neutrinos, and the interpretation in terms of neutrino
oscillations.Comment: 6 pages, 4 figures. Invited talk at the Third International Workshop
on New Worlds in Astroparticle Physics 1-3 September 2000, University of the
Algarve. Faro, Portuga
Constraints to a Galactic Component of the Ice Cube cosmic neutrino flux from ANTARES
The IceCube evidence for cosmic neutrinos in the high-energy starting events
(HESE) sample has inspired a large number of hypothesis on their origin, mainly
due to the poor precision on the measurement of the direction of showering
events. The fact that most of HESE are downward going suggests a possible
Galactic component. This could be originated either by a single point-like
source or to a directional excess from an extended Galactic region. These
hypotheses are reviewed and constrained, using the present available upper
limits from the ANTARES neutrino telescope.
ANTARES detects from sources in the Southern sky with an effective
area larger than that providing the IceCube HESE for TeV and a
factor of about two smaller at 1 PeV. The use of the signal enables
an accurate measurement of the incoming neutrino direction. The Galactic signal
allowed by the IceCube HESE and the corresponding ANTARES limits are studied in
terms of a power law flux , with spectral index ranging
from 2.0 to 2.5 to cover most astrophysical models
Results from the ANTARES Neutrino Telescope
A primary goal of a deep-sea neutrino telescopes as ANTARES is the search for
astrophysical neutrinos in the TeV-PeV range. ANTARES is today the largest
neutrino telescope in the Northern hemisphere. After the discovery of a cosmic
neutrino diffuse flux by the IceCube, the understanding of its origin has
become a key mission in high-energy astrophysics. ANTARES makes a valuable
contribution for sources located in the Southern sky thanks to its excellent
angular resolution in both the muon channel and the cascade channel (induced by
all neutrino flavors).
Assuming various spectral indexes for the energy spectrum of neutrino
emitters, the Southern sky and in particular central regions of our Galaxy are
studied searching for point-like objects and for extended regions of emission.
In parallel, by adopting a multimessenger approach, based on time and/or space
coincidences with other cosmic probes, the sensitivity of such searches can be
considerably augmented. ANTARES has participated to a high-energy neutrino
follow-up of the gravitational wave signal GW150914, providing the first
constraint on high-energy neutrino emission from a binary black hole
coalescence. ANTARES has also performed indirect searches for Dark Matter,
yielding limits for the spin-dependent WIMP-nucleon cross-section that improve
upon those of current direct-detection experiments.Comment: Proceedings of the CRIS2016 (10th Cosmic Ray International Seminar) -
Ischia (NA) Italy, July 4-8, 201
A parameterisation of single and multiple muons in the deep water or ice
Atmospheric muons play an important role in underwater/ice neutrino
detectors. In this paper, a parameterisation of the flux of single and multiple
muon events, their lateral distribution and of their energy spectrum is
presented. The kinematics parameters were modelled starting from a full Monte
Carlo simulation of the interaction of primary cosmic rays with atmospheric
nuclei; secondary muons reaching the sea level were propagated in the deep
water. The parametric formulas are valid for a vertical depth of 1.5-5 km w.e.
and up to 85 deg for the zenith angle, and can be used as input for a fast
simulation of atmospheric muons in underwater/ice detectors.Comment: 25 pages, 8 figure
Physics and astrophysics with high energy v in MACRO
The events collected with the lower part of the MACRO detector at the Gran Sasso Laboratory have been analyzed looking for neutrino-induced muons. Upward throughgoing events have been measured and the result is compared with Monte Carlo prediction. The first results concerning upward stopping muons and partially contained events are also reported. A search has been made for astrophysical point
sources of neutrinos. No point sources have been observed
Future neutrino + Extensive Air Shower challenges
“Multimessenger” astrophysics, connecting traditional astronomy with cosmic ray (CR), γ-ray and neutrino observations, is a new branch of physics connecting particle physics, astrophysics and cosmology. It is made possible by the availability of experimental techniques and detectors developed for high-energy physics. These have allowed the realization of sensible detectors in space (for the measurement of the primary CR flux, search for primary antimatter, astrophysical studies of γ-ray sources up to hundreds of GeV), on the Earth surface (arrays of detectors for the study of the high energy component of CRs, the identification and characterizations of γ-ray sources up to hundreds of TeV), deep underground detectors (for studies of neutrino oscillations, measurement of solar neutrinos, searches for neutrinos from gravitational core-collapse of massive stars) and under kilometers of water or ice (detection of high-energy neutrinos emitted from astrophysical accelerators). The experimental identification of the engines (or class of engines) able to accelerate protons to energies orders of magnitude larger than in the LHC is one of major open problems in multimessenger astrophysics. In additions, almost all experiments enter in the game for the indirect searches for dark matter candidates. All the involved detectors are characterized by long term measurement campaigns in hostile or inaccessible environments, requiring stable, robust, low cost and low-power electronics detectors. Here, we present a brief outlook and perspectives for the multimessenger studies, with particular attentions to cosmic neutrinos and ground-based observatories of air shower
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