Upper limit on the diffuse flux of UHE tau neutrinos from the Pierre Auger Observatory

PIERRE AUGER COLL. J. ABRAHAM, M.T.DOVA ET AL

PHYSICAL REVIEW LETTERS

AMER PHYSICAL SOC

Año: 2008 vol. 100 p. 1 - 5

0031-9007

The surface detector array of the Pierre Auger Observatory is sensitive to Earthskimming tau-neutrinos  that interact in the Earth’s crust. Tau leptons from  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  at EeV energies. Assuming an E−2 differential energy spectrum the limit set at 90 % C.L. is E2 dN /dE < 1.3 × 10−7 GeV cm−2 s−1 sr−1 in the energy range 2 × 1017eV < E < 2 × 1019 eV.