Rigorous bounds on the reduced coupling constant of the K+-p forward elastic amplitude

Positivity of the imaginary part of the forward K-p elastic amplitude on the unphysical region allows the construction of a Stieltjes function H1(z) closely related to a discrepancy function Δ-(ω), evaluated from experimental data on the real and imaginary parts of the amplitude. A set of 159 data points, compatible with the positivity hypothesis, has been selected and all calculations and results are based on practically the whole set. (author)