Risetime at 1000 m: Searching a new SD observable sensitive to mass composition

JARNE, CECILIA; WAHLBERG HERNÁN, DOVA MARÍA TERESA

Arequipa

Otro; 2013 CERN- Latin American School of HEP; 2013

CERN

Extensive air showers induced by cosmic rays of different species contain different number of particles (electrons and muons) at ground. Is is well known that heavy nuclei have larger muon component than lighter nuclei. The time distribution of the shower front particles reaching the ground detectors is sensitive to the muon to electron ratio and hence to primary composition. Of particular interest is the time in which the signal in the detectors rises to half of the total integrated signal (Risetime). The Risetime at 1000 m from the shower axis, obtained on event by event basis, is a robust variable to build different observables carrying information about mass composition. Here we report the last results obtained using MC simulation.