Bound state effects in transverse momentum parton distributions

Abstract

We derive a nonperturbative transverse momentum distribution for partons using a potential model to describe the quark-quark interaction inside the proton. We use this distribution in the calculation of the differential cross section of ${\ensuremath{\pi}}^{0}$ production for intermediate transverse momentum values in $p\ensuremath{-}p$ collisions at high energies. Assuming a variable string tension constant for the quark-quark potential we obtain a very good description of the experimental data at different energies. The corresponding values of the mean transverse momentum of the partons are essentially lower than those obtained using a Gaussian transverse momentum parton distribution. Using the same approach we can also describe the proton production data in the Chicago-Princeton experiment. Our analysis indicates that bound state effects may be important for the description of the experimental data in proton-proton collisions.