Study of the energy spectrum of cosmic rays obtained at the "Hadron 55" installation located at an altitude of 3340 m.

"HADRON-55" with scintillation detectors and ionization calorimeters is used for studies in high-energy gamma-astronomy and cosmic ray physics. The "HADRON-55" consists of two parts - the upper gamma block and the lower hadron block. The gamma block absorbs and detects the electron-photon components of cosmic rays, while hadrons are not absorbed when they pass through the gamma block and begins to form particles in the hadron block. Project's main idea is to select events where there is the interaction in gamma block and no interaction in hadron block. Analysis of experiments results on "HADRON-55" accounts for similar to 6% of such events. The peripheral part of "HADRON-55" consists of 8 scintillation detectors placed in 2 circles with radii of 40 and 100 m. Over 4 years, more than 120,000 events with high energy of 1015 eV were detected.