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تسجيل مستخدم جديدExpected discovery potential and sensitivity of the ANTARES neutrino telescope to neutrino point-like sources
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نشر من قبل
Juan Antonio Aguilar S\\'anchez Mr.
تاريخ النشر
2007
مجال البحث
فيزياء
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English
تأليف
J.A. Aguilar
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The ANTARES telescope is being built in the Mediterranean Sea. The detector consists of a 3D array of photomultipliers (PMTs) that detects the Cherenkov light induced by the muons produced in neutrino interactions. Other signatures can also be detected. Since the neutrino fluxes from point-like sources are expected to be small, it is of the utmost importance to take advantage of the ANTARES pointing accuracy (angular resolution better than 0.3 degrees for muon events above 10 TeV) to disentangle a possible signal from the unavoidable atmospheric neutrino background. In order to distinguish an excess of neutrino events from the background, several searching algorithms have been developed within the ANTARES collaboration. In this contribution, the discovery potential and sensitivity to point-like sources of the ANTARES neutrino telescope are presented.
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KM3NeT will be a network of deep-sea neutrino telescopes in the Mediterranean Sea. The KM3NeT/ARCA detector, to be installed at the Capo Passero site (Italy), is optimised for the detection of high-energy neutrinos of cosmic origin. Thanks to its geo
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A search for cosmic neutrino sources using six years of data collected by the ANTARES neutrino telescope has been performed. Clusters of muon neutrinos over the expected atmospheric background have been looked for. No clear signal has been found. The
most signal-like accumulation of events is located at equatorial coordinates RA=$-$46.8$^{circ}$ and Dec=$-$64.9$^{circ}$ and corresponds to a 2.2$sigma$ background fluctuation. In addition, upper limits on the flux normalization of an E$^{-2}$ muon neutrino energy spectrum have been set for 50 pre-selected astrophysical objects. Finally, motivated by an accumulation of 7 events relatively close to the Galactic Centre in the recently reported neutrino sample of the IceCube telescope, a search for point sources in a broad region around this accumulation has been carried out. No indication of a neutrino signal has been found in the ANTARES data and upper limits on the flux normalization of an E$^{-2}$ energy spectrum of neutrinos from point sources in that region have been set. The 90% confidence level upper limits on the muon neutrino flux normalization vary between 3.5 and 5.1$times$10$^{-8}$ GeV$,$cm$^{-2}$s$^{-1}$, depending on the exact location of the source.
A search for cosmic neutrino sources using the data collected with the ANTARES neutrino telescope between early 2007 and the end of 2015 is performed. For the first time, all neutrino interactions --charged and neutral current interactions of all fla
vours-- are considered in a search for point-like sources with the ANTARES detector. In previous analyses, only muon neutrino charged current interactions were used. This is achieved by using a novel reconstruction algorithm for shower-like events in addition to the standard muon track reconstruction. The shower channel contributes about 23% of all signal events for an $E^{-2}$ energy spectrum. No significant excess over background is found. The most signal-like cluster of events is located at $(alpha,delta) = (343.8^circ, 23.5^circ)$ with a significance of $1.9sigma$. The neutrino flux sensitivity of the search is about $E^2 dvarPhi/dE = 6cdot10^{-9} GeV cm^{-2} s^{-1}$ for declinations from $-90^circ$ up to $-42^circ$, and below $10^{-8} GeV cm^{-2} s^{-1}$ for declinations up to $5^{circ}$. The directions of 106 source candidates and of 13 muon track events from the IceCube HESE sample are investigated for a possible neutrino signal and upper limits on the signal flux are determined.
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. Techniqu
es 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 2.5$sigma$. 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 2.1$sigma$.
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