Atmospheric effects on extensive air showers observed with the Surface Detector of the Pierre Auger Observatory

Understand

Atmospheric parameters, such as pressure (P), temperature (T) and density, affect the development of extensive air showers initiated by energetic cosmic rays.

• We have studied the impact of atmospheric variations on extensive air showers by means of the surface detector of the Pierre Auger Observatory.
• The rate of events shows a ~10% seasonal modulation and ~2% diurnal one.
• We find that the observed behaviour is explained by a model including the effects associated with the variations of pressure and density.