English: The surface extensive air shower detector stations of GAMMA Experiment are located on 5 concentric circles of radii 20, 28, 50, 70 and 100 m. Each station contains 3 square plastic scintillation detectors, 3x(1x1x0.05 m³), to measure the energy deposit of shower charged particles.

A photomultiplier tube is positioned on the top of the aluminum casing covering each scintillator. One of the three detectors of each station is examined by two photomultipliers, one of which is designed for fast timing measurements.

150 underground muon scintillation detectors (muon carpet) are compactly arranged in the underground hall under 2.3 Kg/cm² of concrete and rock to detect shower muon component with energies more that ~5 GeV.