A new surface parameter for composition studies at high energies

G. ROS; A. D. SUPANITSKY; G. A. MEDINA-TANCO; L. DEL PERAL; M. D. RODRÍGUEZ FRÍAS

Conferencia; 31st Intenational Cosmic Ray Conference; 2009

A new family of parameters intended for composition studies is presented. They make exclusive use of surface data combining the information from the total signal at each triggered detector and the array geometry. We perform an analytical study of these composition estimators in order to assess their reliability, stability and possibleoptimization. The influence of the different slopes of the proton and Iron lateral distribution function on the discrimination power of the estimators is also studied. Additionally, the stability of the parameterin face of a possible underestimation of the size of the muon  component by the shower simulation codes, as it is suggested by experimental evidence, is also studied.