Upper Limit on the Diffuse Flux of Ultrahigh Energy Tau Neutrinos from the Pierre Auger Observatory

PIERRE AUGER COLLABORATION: SON 452 AUTORES. A. PICHEL

PHYSICAL REVIEW LETTERS

AMER PHYSICAL SOC

Año: 2008 vol. 100 p. 211101 - 211101

0031-9007

The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth’s crust. Tau leptons from the tau neutrino charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of tau neutrino at EeV energies. Assuming an Enu^-2 differential energy spectrum the limit set at 90% C.L. is Enu2dNnu=dEnu < 1.3 x 10^-7 GeV cm^-2 s^-1 sr^-1 in the energy range 2 x 10^17 eV<Enu < 2 x 10^19 eV.