New results on the Sb application to photon discrimination

GERMÁN ROS; DANIEL SUPANITSKY; GUSTAVO A. MEDINA-TANCO; LUIS DEL PERAL; MARÍA DOLORES RODRÍGUEZ-FRÍAS

Malargüe

Otro; Reunion de la Colaboración Internacional Pierre Auger; 2012

Colaboración Internacional Pierre Auger

This GAP presents some new results on the application of the Sb parameter to search for photon events. A new set of simulations is used with ten times more statistics than our previous work on this topic [1], covering the energy range from 10^18.5 to 10^19.6 eV. Sb is optimized analyzing each energy and zenith angle bin. The new optimization is also confirmed by using our own Monte-Carlo simulation program that, in addition, allows to analyze arrays of different size and geometry. Sb dependence with primary energy and zenith angle are also studied. Finally, the efficiency and discrimination power of several SD parameters traditionally usedfor photon searches (risetime, radius of curvature, S b ) are compared. The impact on the discrimination power of the uncertainty in the energy reconstruction is also studied.