Atmospheric neutrinos are produced during cascades initiated by the interaction of primary cosmic rays with air nuclei. In this paper, a measurement of the atmospheric
νμ + ¯νμ energy spectrum in the ...energy range 0.1–200 TeV is presented, using data collected by the ANTARES underwater neutrino telescope from 2008 to 2011. Overall,
the measured flux is ∼25 % higher than predicted by the conventional neutrino flux, and compatible with the measurements
reported in ice. The flux is compatible with a single power-law dependence with spectral index γmeas = 3.58 ± 0.12. With the present statistics the contribution of prompt neutrinos cannot be established.
► Magnetic monopoles are hypothetical particles predicted in unified theories. ► Relativistic monopoles could be detected in a neutrino telescope. ► A search for upgoing monopoles has been performed ...using 2008 ANTARES data. ► The obtained flux limits are stronger than limits from other experiments.
Magnetic monopoles are predicted in various unified gauge models and could be produced at intermediate mass scales. Their detection in a neutrino telescope is facilitated by the large amount of light emitted compared to that from muons. This paper reports on a search for upgoing relativistic magnetic monopoles with the ANTARES neutrino telescope using a data set of 116days of live time taken from December 2007 to December 2008. The one observed event is consistent with the expected atmospheric neutrino and muon background, leading to a 90% C.L. upper limit on the monopole flux between 1.3×10−17 and 8.9×10−17cm−2s−1sr−1 for monopoles with velocity β⩾0.625.
Light-weight spherical mirrors for Cherenkov detectors Cisbani, E.; Colilli, S.; Crateri, R. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2003, Letnik:
496, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Light-weight spherical mirrors have been appositely designed and built for the gas threshold Cherenkov detectors of the two Hall A spectrometers. The mirrors are made of a
1
mm
thick aluminized ...plexiglass sheet, reinforced by a rigid backing consisting of a phenolic honeycomb sandwiched between two carbon fiber mats epoxy glued. The produced mirrors have a thickness equivalent to 0.55% of radiation length, and an optical slope error of about
5.5
mrad
. These characteristics make these mirrors suitable for the implementation in Cherenkov threshold detectors. Ways to improve the mirror features are also discussed in view of their possible employment in RICH detectors.
Basic instrumentation for Hall A at Jefferson Lab Arrington, J.; Averett, T.; Beise, E.J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2004, Letnik:
522, Številka:
3
Journal Article
Recenzirano
Odprti dostop
The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electro- and photo-induced reactions at very high luminosity and good momentum and angular ...resolution for at least one of the reaction products. The central components of Hall A are two identical high resolution spectrometers, which allow the vertical drift chambers in the focal plane to provide a momentum resolution of better than 2×10
−4. A variety of Cherenkov counters, scintillators and lead-glass calorimeters provide excellent particle identification. The facility has been operated successfully at a luminosity well in excess of
10
38
cm
−2
s
−1
. The research program is aimed at a variety of subjects, including nucleon structure functions, nucleon form factors and properties of the nuclear medium.
Results are presented of a search for cosmic sources of high-energy neutrinos with the ANTARES neutrino telescope. The data were collected during 2007 and 2008 using detector configurations ...containing between 5 and 12 detection lines. The integrated live time of the analyzed data is 304 days. Muon tracks are reconstructed using a likelihood-based algorithm. Studies of the detector timing indicate a median angular resolution of 0.5 ? 0.1 deg. The neutrino flux sensitivity is 7.5 X 10--8(E Delta *n/ GeV)--2 GeV--1 s--1 cm--2 for the part of the sky that is always visible ( Delta *d < --48 deg), which is better than limits obtained by previous experiments. No cosmic neutrino sources have been observed.
The ANTARES high-energy neutrino telescope is a three-dimensional array of about 900 photomultipliers distributed over 12 mooring lines installed in the Mediterranean Sea. Between February and ...November 2007 it acquired data in a 5-line configuration. The zenith angular distribution of the atmospheric muon flux and the associated depth–intensity relation are measured and compared with previous measurements and Monte Carlo expectations. An evaluation of the systematic effects due to uncertainties on environmental and detector parameters is presented.
Performance of the front-end electronics of the ANTARES neutrino telescope Al Samarai, I.; Albert, A.; Anghinolfi, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2010, Letnik:
622, Številka:
1
Journal Article
Recenzirano
Odprti dostop
ANTARES is a high-energy neutrino telescope installed in the Mediterranean Sea at a depth of 2475m. It consists of a three-dimensional array of optical modules, each containing a large ...photomultiplier tube. A total of 2700 front-end ASICs named analogue ring samplers (ARS) process the phototube signals, measure their arrival time, amplitude and shape as well as perform monitoring and calibration tasks. The ARS chip processes the analogue signals from the optical modules and converts information into digital data. All the information is transmitted to shore through further multiplexing electronics and an optical link. This paper describes the performance of the ARS chip; results from the functionality and characterization tests in the laboratory are summarized and the long-term performance in the apparatus is illustrated.
The cross section for exclusive pisup + electroproduction on the proton has been measured near threshold for the first time at two different values of the virtual photon polarization (var ...epsilonsimilar to0.2 and var epsilonsimilar to0.7). Using the low energy theorem for this reaction we deduce the axial and pseudoscalar weak form factors ital Gsub ital A and ital Gsub ital P at vert barital tvert bar=0.073, 0.139, and 0.179 (GeV/ital c)sup 2. The slope of ital Gsub ital A agrees with the value obtained in neutrino experiments. ital Gsub ital P satisfies the pion pole dominance hypothesis, which is thus verified for the first time in this range of transfer.
The ANTARES neutrino telescope, located 40km off the coast of Toulon in the Mediterranean Sea at a mooring depth of about 2475m, consists of twelve detection lines equipped typically with 25 storeys. ...Every storey carries three optical modules that detect Cherenkov light induced by charged secondary particles (typically muons) coming from neutrino interactions. As these lines are flexible structures fixed to the sea bed and held taut by a buoy, sea currents cause the lines to move and the storeys to rotate. The knowledge of the position of the optical modules with a precision better than 10 cm is essential for a good reconstruction of particle tracks. In this paper the ANTARES positioning system is described. It consists of an acoustic positioning system, for distance triangulation, and a compass-tiltmeter system, for the measurement of the orientation and inclination of the storeys. Necessary corrections are discussed and the results of the detector alignment procedure are described.
A recent analysis of the Fermi Large Area Telescope data provided evidence for a high-intensity emission of high-energy gamma rays with a E−2 spectrum from two large areas, spanning 50° above and ...below the Galactic centre (the “Fermi bubbles”). A hadronic mechanism was proposed for this gamma-ray emission making the Fermi bubbles promising source candidates of high-energy neutrino emission. In this work Monte Carlo simulations regarding the detectability of high-energy neutrinos from the Fermi bubbles with the future multi-km3 neutrino telescope KM3NeT in the Mediterranean Sea are presented. Under the hypothesis that the gamma-ray emission is completely due to hadronic processes, the results indicate that neutrinos from the bubbles could be discovered in about one year of operation, for a neutrino spectrum with a cutoff at 100TeV and a detector with about 6km3 of instrumented volume. The effect of a possible lower cutoff is also considered.
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