Moments of rapidity distributions as a measure of short-range fluctuations in high-energy collisions

Abstract It is proposed to study the dependence of factorial moments of the rapidity distribution on the size δy of the resolution. It is shown that if the fluctuations are purely statistical no variation of moments δy is expected, and thus observation of such a variation indicates the presence of genuine fluctuations of physical origin. The region in which the change occurs corresponds to the size (in rapidity) of the observed fluctuations. Intermittency, i.e. fluctuations of many different sizes, would show up as a power-law behaviour of moments on δy . A good experimental resolution can be obtained from the rapidity distribution of high multiplicity events.