Planar experiment as possible method of QCD tube investigation

It is proposed to distinguish the plane events with Δqtr/q-bartr<<1 in the narrow region of transverse momenta in processes of nultiple hadron production in soft hdron-hadron interactions. Probablity of formation of such events, depending on multiplicity of charged particles (n) and Δqtr/q-bartr at azimuth-independent distribution of transverse momenta in the phase volume was calculated. The arguments, owing to which the probability of plane event observation grows sufficiently at fragmentation of isolated QCD strings, are presented. Probability of formation of plane events, conditioned by isolated QCD string fragmentation, decreases with momentum as ∼ Plab-1/2. 6 refs.; 1 fig