THE EFFECTIVE TECHNIQUE OF THE CHARGED-PARTICLES BACKGROUND DISCRIMINATION IN THE ATMOSPHERIC CHERENKOV LIGHT DETECTORS

It is shown that parameters of flashes, detected by multichannel image cameras of Cherenkov detectors with closed lids are close to those of Cherenkov flashes initiated by VHE gamma-quanta in the Earth atmosphe re. Even after application of criteria for gamma-like events selection a considerable part of those flashes may be misclassified and accepte d as gammas. Since the flashes of this kind are detected also during n ormal measurements with the opened lids of image cameras it just incre ases the background and, as a consequence, decreases the detector sens itivity even when one uses an anticoincidence scintillator shield arou nd the camera (its efficiency is about 75%). The use of detectors cons isting of two (or more) sections no less than 20-30 m apart permits us to avoid the detection of both muon and local charged particles flash es in the course of observations.