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
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
γ
meas
=3.58±0.12. With the present statistics the contribution of prompt neutrinos cannot be established.
Advanced
LIGO
detected a significant gravitational wave signal (GW170104) originating from the coalescence of two black holes during the second observation run on January 4th, 2017. An all-sky ...high-energy neutrino follow-up search has been made using data from the
Antares
neutrino telescope, including both upgoing and downgoing events in two separate analyses. No neutrino candidates were found within
±
500
s around the GW event time nor any time clustering of events over an extended time window of
±
3
months. The non-detection is used to constrain isotropic-equivalent high-energy neutrino emission from GW170104 to less than
∼
1.2
×
10
55
erg for a
E
-
2
spectrum. This constraint is valid in the energy range corresponding to the 5–95% quantiles of the neutrino flux 3.2 TeV; 3.6 PeV, if the GW emitter was below the
Antares
horizon at the alert time.
A search for a diffuse flux of astrophysical muon neutrinos, using data collected by the ANTARES neutrino telescope is presented. A (0.83×2π) sr sky was monitored for a total of 334 days of ...equivalent live time. The searched signal corresponds to an excess of events, produced by astrophysical sources, over the expected atmospheric neutrino background. The observed number of events is found compatible with the background expectation. Assuming an E−2 flux spectrum, a 90% c.l. upper limit on the diffuse νμ flux of E2Φ90%=5.3×10−8 GeVcm−2s−1sr−1 in the energy range 20 TeV–2.5 PeV is obtained. Other signal models with different energy spectra are also tested and some rejected.
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.
A novel method to analyse the spatial distribution of neutrino candidates recorded with the ANTARES neutrino telescope is introduced, searching for an excess of neutrinos in a region of arbitrary ...size and shape from any direction in the sky. Techniques originating from the domains of machine learning, pattern recognition and image processing are used to purify the sample of neutrino candidates and for the analysis of the obtained skymap. In contrast to a dedicated search for a specific neutrino emission model, this approach is sensitive to a wide range of possible morphologies of potential sources of high-energy neutrino emission. The application of these methods to ANTARES data yields a large-scale excess with a post-trial significance of 2.5σ. Applied to public data from IceCube in its IC40 configuration, an excess consistent with the results from ANTARES is observed with a post-trial significance of 2.1σ.
We present a measurement of the muon neutrino–nucleon inclusive charged current cross section, off an isoscalar target, in the neutrino energy range 2.5⩽Eν⩽40 GeV. The significance of this ...measurement is its precision, ±4% in 2.5⩽Eν⩽10 GeV, and ±2.6% in 10⩽Eν⩽40 GeV regions, where significant uncertainties in previous experiments still exist, and its importance to the current and proposed long baseline neutrino oscillation experiments.
KM3NeT aims to build a cubic-kilometer scale neutrino telescope in the Mediterranean Sea based on a 3D array of photomultiplier tubes. A dedicated ASIC, named SCOTT, has been developed for the ...readout electronics of the PMTs: it uses up to 16 adjustable thresholds to digitize the signals with the multi-time-over-threshold technique. Digital outputs of discriminators feed a circular sampling memory and a “first in first out” digital memory for derandomization. At the end of the data processing, the ASIC produces a digital waveform sampled at 800MHz. A specific study was carried out to process PMT data and has showed that five specifically chosen thresholds are suited to reach the required timing precision. A dedicated method based on the duration of the signal over a given threshold allows an equivalent timing precision at any charge. A charge estimator using the information from the thresholds allows a charge determination within less than 20% up to 60pe.