Bonn 2010 – wissenschaftliches Programm
T 106.4: Vortrag
Freitag, 19. März 2010, 14:45–15:00, HG VIII
Limit on the diffuse flux of downward going neutrinos with the surface detector of the Pierre Auger Observatory — •Dariusz Góra — Institut für experimentelle Kernphysik, Karlsruher Institut für Technologie (KIT), Karlsruhe, Germany — Institute of Nuclear Physics PAN, Cracow, Poland
The surface detector array of the Pierre Auger Observatory is sensi- tive to ultra high energy (UHE) neutrinos of all flavours and directions ranging from few degrees below the horizon (up-going) to about 75 de- grees above the horizon (down-going). Although the largest contribu- tion to the total expected event rate comes from the so-called "earth- skimming" up-going tau neutrinos, the contribution of down-going neu- trinos can not be neglected. Extensive air showers induced by down- going neutrinos are characterized by very elongated and asymmetric footprints and a significant electromagnetic component. Electrons and gamma-rays produce broad timing signals, whereas inclined hadronic showers give rise to narrower signals mostly due to the surviving secondary muons. Comparing the data collected from 1 January 2004 to 28 February 2009 with the expectations from the simulation of down-going neutrinos, we derive a competitive limit on the all-flavour diffuse neutrino flux.