اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدAn improved limit to the diffuse flux of ultra-high energy neutrinos from the Pierre Auger Observatory
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Neutrinos in the cosmic ray flux with energies near 1 EeV and above are detectable with the Surface Detector array of the Pierre Auger Observatory. We report here on searches through Auger data from 1 January 2004 until 20 June 2013. No neutrino candidates were found, yielding a limit to the diffuse flux of ultra-high energy neutrinos that challenges the Waxman-Bahcall bound predictions. Neutrino identification is attempted using the broad time-structure of the signals expected in the SD stations, and is efficiently done for neutrinos of all flavors interacting in the atmosphere at large zenith angles, as well as for Earth-skimming neutrino interactions in the case of tau neutrinos. In this paper the searches for downward-going neutrinos in the zenith angle bins $60^circ-75^circ$ and $75^circ-90^circ$ as well as for upward-going neutrinos, are combined to give a single limit. The $90%$ C.L. single-flavor limit to the diffuse flux of ultra-high energy neutrinos with an $E^{-2}$ spectrum in the energy range $1.0 times 10^{17}$ eV - $2.5 times 10^{19}$ eV is $E_ u^2 dN_ u/dE_ u < 6.4 times 10^{-9}~ {rm GeV~ cm^{-2}~ s^{-1}~ sr^{-1}}$.
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Results of a search for ultra-high-energy neutrinos with the Pierre Auger Observatory from the direction of the blazar TXS 0506+056 are presented. They were obtained as part of the follow-up that stemmed from the detection of high-energy neutrinos an
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With the Surface Detector array (SD) of the Pierre Auger Observatory we can detect neutrinos with energy between $10^{17},$eV and $10^{20},$eV from point-like sources across the sky, from close to the Southern Celestial Pole up to $60^circ$ in declin
ation, with peak sensitivities at declinations around $sim -53^circ$ and $sim+55^circ$, and an unmatched sensitivity for arrival directions in the Northern hemisphere. A search has been performed for highly-inclined air showers induced by neutrinos of all flavours with no candidate events found in data taken between 1 Jan 2004 and 31 Aug 2018. Upper limits on the neutrino flux from point-like steady sources have been derived as a function of source declination. An unrivaled sensitivity is achieved in searches for transient sources with emission lasting over an hour or less, if they occur within the field of view corresponding to the zenith angle range between $60^circ$ and $~95^circ$ where the SD of the Pierre Auger Observatory is most sensitive to neutrinos.
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The Surface Detector of the Pierre Auger Observatory is sensitive to neutrinos of all flavours above 0.1 EeV. These interact through charged and neutral currents in the atmosphere giving rise to extensive air showers. When interacting deeply in the a
tmosphere at nearly horizontal incidence, neutrinos can be distinguished from regular hadronic cosmic rays by the broad time structure of their shower signals in the water-Cherenkov detectors. In this paper we present for the first time an analysis based on down-going neutrinos. We describe the search procedure, the possible sources of background, the method to compute the exposure and the associated systematic uncertainties. No candidate neutrinos have been found in data collected from 1 January 2004 to 31 May 2010. Assuming an E^-2 differential energy spectrum the limit on the single flavour neutrino is (E^2 * dN/dE) < 1.74x10^-7 GeV cm^-2 s^-1 sr^-1 at 90% C.L. in the energy range 1x10^17 eV < E < 1x10^20 eV.
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