On the fluctuations of the fluorescence photon yield of electrons in extensive air showers for different atmospheric conditions

The air fluorescence technique has long been used to detect extensive air showers and to reconstruct its geometry and energy. The fluorescence photon yield of an electron in air is of main importance in the reconstruction procedure. Several experiments are trying to measure in detail the dependency of the yield with energy. In this work we discuss the calculation of the fluorescence yield convoluted with the energy spectrum of particles in the shower as a function of age. We study the fluctuations of the yield resultant from different atmospheric conditions. We calculate the fluorescence yield as a function of height for the US Standard model and for the winter and summer conditions of the Auger Observatory in Argentine. Using the relation between average Xmax and energy we calculate the fluctuations between winter and summer seasons as a function of energy for proton and iron nuclei as primary particles. The influences of this fluctuation in the energy error as a function of energy are also discussed.