Primary Energy Measurement with EAS Cherenkov Light: Experiment QUEST and CORSIKA Simulation

A new primary mass independent method of energy measurement has been developed by exploiting: a) the joint analysis of the shower size, obtained by EAS-TOP, and of the EAS atmospheric Cherenkov light lateral distribution, obtained by the QUEST array, and b) simulations based on the CORSIKA/QGSJET code. The method is based on the correlation between the size/energy ratio and the steepness of Cherenkov light lateral distribution and has been compared with a "classical" one based on the Cherenkov light flux at a fixed distance (175 m) from the EAS core. An absolute energy calibration of the EAS atmospheric Cherenkov light flux has been obtained.