baryon - antibaryon production in two - photon collisions

We study baryon pair production in two-photon collisions, γγ → BB̄, within perturbative quantum chromodynamics, treating baryons as quark-diquark systems. We extend previous work within the same approach by treating constituent-mass effects systematically by means of an expansion in the small parameter (mass/photon energy). Our approach enables us to give a consistent description of the cross sections for all octet baryon channels. Adopting the model parameters from foregoing work, we are able to reproduce the most recent large-momentum-transfer data from LEP for the pp̄, ΛΛ̄, and ΣΣ̄ channels in a quite satisfactory way. We also briefly address the crossed process for the proton channel, γp → γp. PACS. 12.38.Bx perturbative calculation – 13.60.Rj baryon production – 13.60.Fz elastic and Compton scattering