Measurement of the cosmic rays light component (pHe) primary spectrum with ARGO-YBJ

The ARGO-YBJ experiment, located at the Yangbajing Cosmic Ray Laboratory (Tibet, 4300 m a.s.l., 606 g/cm 2) has an high segmentation that allows the detection of air showers with greater detail and lower energy threshold (a few hundred GeV) compared to other EAS arrays. The spectrum of the primary cosmic ray light (pHe) component in the energy range ∼10-100TeV is measured selecting quasi-vertical showers (θ<15°) with the reconstructed core position located in a 40×40 m 2 fiducial area. The results are compared with other measurements carried out with direct methods. © 2012 Elsevier B.V