Simple Behavior of Primary Cross Sections for Low Mass Particles in p-pbar Collisions at y=0 and sqrt(s)=1.8 TeV

Abstract

A set of inclusive cross sections at zero rapidity, dσ/dy|y=0, is presented for pp interactions at center of mass energy √ s = 1.8 TeV. Six elementary particle cross sections are corrected for secondary contributions from decays of higher mass resonances in order to produce a set of primary cross sections. The primary cross sections per spin state are well described by dσ p /dy|y=0 = 0.721, where m is the particle rest mass, T = hc/r h , and r h = 0.97 fm. The deuterium production cross section is also described if r h is replaced by rA = r h A 1/3 . The same exponential in m and T describes primary charm fractions in e + e − collisions at least up to the J/ψ mass. There is no significant evidence for strangeness or charm suppression if only primary production of light hadrons is considered. There is evidence that the primary cross section for each particle may have the same value for pp and pp collisions and that it may have nearly constant values between √ s = 63GeV and √ s = 1800 GeV. Fits to the final state transverse momenta of the particles using a gas model favor a temperature T=132 MeV, a chemical potential µ = 129 MeV, and a transverse flow of the gas with β f = 0.27.