Update of the neutrino and photon limits from the Pierre Auger Observatory

PIERRE AUGER COLLABORATION; PABLO PIERONI

The Hauge

Conferencia; ICRC 2015; 2015

Ultra-high energy neutrinos and photons, with energies above 1 EeV and 10 EeV respectively, can be detected with the Surface Detector array (SD) of the Pierre Auger Observatory. Downwardgoing neutrinos of all flavours interacting in the atmosphere at zenith angles θ > 60◦ , upwardgoing tau neutrinos (?Earth-skimming?), as well as photons in the zenith range 30◦ − 60◦ can be identified through the broad time-structure of the signals expected to be induced in the SD stations. An additional signature for photon-induced air showers is the steeper lateral distribution of secondary particles at ground with respect to the nucleonic showers. Stringent limits are set to the diffuse flux of ultra-high energy (UHE) neutrinos and photons, using data collected between 2004 and mid-2013, under the hypothesis of an E−2 spectrum for signal primaries.