Sb and other SD parameters for photon searches: a comparison under different energy reconstruction strategies

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

Malargüe

Otro; Reunion de la Colaboración Internacional Pierre Auger; 2011

Colaboración Internacional Pierre Auger

We have compared the reliability of the inferred photon fraction obtained using several parameters from the surface detector (SD) in the energy range from 10^19.0 to 10 19.6 eV. These parameters are the rise time at 1000 m from the shower axis (t_1/2(1000)), the radius of curvature (R), the number of candidate stations (N_cand) and Sb. Two energy reconstruction techniques has been considered. First, the standard Auger hybrid calibration is used which assumes that all the primaries are hadrons. Second, the primary energy is determined by using the pure SD method developed for photon events that has been previously used in Auger to calculate the photonlimits from SD data.