No Arabic abstract
The ANTARES detector is at present the most sensitive neutrino telescope in the Northern Hemisphere. The highly significant cosmic neutrino excess observed by the Antarctic IceCube detector can be studied with ANTARES, exploiting its complementing field of view, exposure, and lower energy threshold. Searches for an all-flavor diffuse neutrino signal, covering 9 years of ANTARES data taking, are presented in this letter. Upward-going events are used to reduce the atmospheric muon background. This work includes for the first time in ANTARES both track-like (mainly $ u_mu)$ and shower-like (mainly $ u_e$) events in this kind of analysis. Track-like events allow for an increase of the effective volume of the detector thanks to the long path traveled by muons in rock and/or sea water. Shower-like events are well reconstructed only when the neutrino interaction vertex is close to, or inside, the instrumented volume. A mild excess of high-energy events over the expected background is observed in 9 years of ANTARES data in both samples. The best fit for a single power-law cosmic neutrino spectrum, in terms of per-flavor flux at 100 TeV, is $Phi_0^{1f}(100 textrm{TeV}) = left(1.7pm 1.0right) times$10$^{-18}$,GeV$^{-1}$,cm$^{-2}$,s$^{-1}$,sr$^{-1}$ with spectral index $Gamma = 2.4^{+0.5}_{-0.4}$. The null cosmic flux assumption is rejected with a significance of 1.6$sigma$.
The main goal of the ANTARES neutrino telescope is the identification of neutrinos from cosmic accelerators. The good visibility towards the Southern sky for neutrino energies below 100 TeV and the good angular resolution for reconstructed events make the telescope excellent to test for the presence of point-like sources, especially of Galactic origin. The median angular resolution for track-like events (mainly from $ u_{mu}$ CC interactions) is $0.4^{circ}$ while the median angular resolution for contained shower-like events (mainly from $ u_{e}$ CC and all-flavour NC interactions) is $3^{circ}$. Recently the ANTARES Collaboration published the result of the search for cosmic point-like neutrino sources using track-like and shower-like events collected during nine years of data taking. In this contribution, an update to this analysis using eleven years of data recorded between early 2007 and the end of 2017, for a total livetime of 3136 days, is presented. Moreover, the results of a search for time and space correlation between the ANTARES events and 54 IceCube tracks and those of the searches for neutrino candidates associated with the IceCube-170922A event or from the direction of the TXS 0506+056 blazar are reported.
A search for a diffuse flux of astrophysical muon neutrinos, using data collected by the ANTARES neutrino telescope is presented. A $(0.83times 2pi)$ 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 $ u_mu$ flux of $E^2Phi_{90%} = 5.3 times 10^{-8} mathrm{GeV cm^{-2} s^{-1} sr^{-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.
Using data recorded with the ANTARES telescope from 2007 to 2015, a new search for dark matter annihilation in the Milky Way has been performed. Three halo models and five annihilation channels, $rm WIMP + WIMP to b bar b, W^+ W^-, tau^+ tau^-, mu^{+} mu^{-}$ and $ u bar{ u}$, with WIMP masses ranging from 50 $frac{text{GeV}}{text{c}^2}$ to 100 $frac{text{TeV}}{text{c}^2}$, were considered. No excess over the expected background was found, and limits on the thermally averaged annihilation cross--section were set.
A search for magnetic monopoles using five years of data recorded with the ANTARES neutrino telescope from January 2008 to December 2012 with a total live time of 1121 days is presented. The analysis is carried out in the range $beta$ $>$ $0.6$ of magnetic monopole velocities using a strategy based on run-by-run Monte Carlo simulations. No signal above the background expectation from atmospheric muons and atmospheric neutrinos is observed, and upper limits are set on the magnetic monopole flux ranging from $5.7 times 10^{-16}$ to $1.5 times 10^{-18}$ cm$^{-2} cdot $ s$^{-1} cdot $ sr$^{-1}$.
The presented study is an updated search for magnetic monopoles using data taken with the ANTARES neutrino telescope over a period of 10 years (January 2008 to December 2017). In accordance with some grand unification theories, magnetic monopoles were created during the phase of symmetry breaking in the early Universe, and accelerated by galactic magnetic fields. As a consequence of their high energy, they could cross the Earth and emit a significant signal in a Cherenkov-based telescope like ANTARES, for appropriate mass and velocity ranges. This analysis uses a run-by-run simulation strategy, as well as a new simulation of magnetic monopoles taking into account the Kasama, Yang and Goldhaber model for their cross section with matter. The results obtained for relativistic magnetic monopoles with velocity higher than 0.817c, where c is the speed of light in vacuum, are presented.