THE PAPER "The quark hypothesis and relations between cross sections at high energies", E.M. Levin and L.L. Frankfurt (1965)
Created by , 2015-03-20 16:41:02
L.L.Frankfurt,
Department of particle physics,Tel Aviv University,Israel
In the paper [1] derived formula of impulse approximation for the collisions of ultra relativistic composite systems by exploring non relativistic quark model of hadrons suggested by Zweig (1965,unpublished ). Application of this formula to the collisions of ultra relativistic hadrons as the systems consisting of few constituent quarks allowed to derive relations between cross sections of hadron-hadron collisions. These relations agreed with numerous data. Agreement with data of the prediction: σ(pp) /σ (πp) = 3/2 i.e. to the ratio of the number of constituents in the wave functions of proton(anti proton) and pion becomes one of
fundamental confirmations of quark hypothesis.
Some concepts introduced in the paper were incorporated into current theoretical approaches . The assumption that the radius of a quark is significantly smaller than radius of a hadron found explanation in terms of asymptotic freedom in quantum chromodynamics. The assumed in the paper dominance of hadron-hadron collisions at central impact parameters and neglect by scattering off meson field of a nucleon contradicted to the basic ideas of S matrix of that time but they are in line with current data and theoretical approaches . The Lorentz transformation of the rest frame wave function of a hadron into frame where this hadron is energetic uses light cone variables like fraction of energetic hadron momentum carried by interacting quark. This was incorporated later into Feynman parton model.
[1] E.M. Levin and L.L. Frankfurt Pis'ma Zh.Eksp. Teor. Fiz. 2, 65 (1965)