Sensitivity of ARGO-YBJ to different composition models in the energy range 10÷500 TeV

The ARGO-YBJ experiment is currently under construction at the Yangbajing Cosmic Ray Laboratory (4300 m a.s.l.). The detector consists of a central carpet, 74 x 78 m(2), made of a single layer of Resistive Plate Counters (RPCs), and surrounded by a partially instrumented guard ring for a total instrumented area of about 6700 M-2 The digital read-out, performed by means of pick-up electrodes 6.7 x 62 cm(2) (strip), allows to measure the charged particle number of small size air showers. The technique of counting the number of fired strips on the ARGO carpet corresponds to operate in the 10 divided by 500 TeV energy region where both direct and indirect measurements on the primary cosmic radiation have been performed. Many composition models have been proposed by different experiments. In this work we discuss the ability of the ARGO detector to discriminate among some models.