Analytical properties of inclusive interaction over cos THETA in the ladder model with asymptotically constant total cross-section

It is shown that the hypothesis of the analyticity of a single-particle inclusive distribution in cos THETA is fulfilled in the ladder PHI3 model with an asymptotic constant cross section. It has been established that at a zero mass of a particle observed the singularity of the inclusive cross section in cos THETA nearest to zero tends to unity when s → infinity, while the analyticity ellipse degenerates to a segment -1(<=)cos THETA (<=) 1 (s is the square of the total energy in the centre-of-mass system)