Eur. Phys. J. C (2007) 49: 569-580
https://doi.org/10.1140/epjc/s10052-006-0185-3

Regular Article - Theoretical Physics

UCLA space-time area law model: A persuasive foundation for hadronization

Department of Physics and Astronomy, University of California, Los Angeles, CA, 90095, USA

^* e-mail: sabachi@physics.ucla.edu

Received: 11 June 2006
Revised: 14 November 2006
Published online: 6 January 2007

Abstract

From the studies of rates and distributions of heavy quark (c, b) mesons we have developed additional evidence that hadron formation, at least in the simplest environment of e⁺e^- collisions, is dominantly controlled by a space-time area law (“STAL”), an approach suggested by both non-perturbative QCD and relativistic string models. From the dynamics of heavy quarks whose classical space-time world-lines deviate significantly from the light-cone, we report the exact calculation of the relevant space-time area and the derivation of a Lorentz invariant variable, z_eff, which reduces to the light-cone momentum fraction z for low mass quarks. Using z_eff in the exponent of our fragmentation function in place of z, we find persuasive agreement with L=0, 1 charmed and bottom meson data as well as for u, d, s L=0 states. Presuming STAL to be a valid first-order description for all these meson data, we find the scale of other possible second-order effects to be limited to ∼20% or less of the observed rates. The model favors a b-quark mass of ∼4.5 GeV.