Transverse Momentum Broadening in Semi-inclusive DIS on Nuclei

TL;DR

This paper models the transverse momentum broadening of hadrons in semi-inclusive DIS on nuclei, attributing it mainly to the initial quark propagation stage and comparing results with HERMES data.

Contribution

It introduces a three-stage model of hadron formation in SIDIS that isolates the quark propagation stage as the primary source of transverse momentum broadening.

Findings

Quark-nucleon collisions account for most $p_ot$-broadening.

Model agrees with HERMES preliminary data for various nuclei.

Prehadron elastic scatterings have minimal impact at HERMES energies.

Abstract

Using a three stage model of hadron formation we calculate the change of the transverse momentum distribution of hadrons produced in semi-inclusive deep inelastic scattering (SIDIS) on nuclei. In the first stage after its interaction with the virtual photon, the struck quark propagates quasi free in the nuclear environment undergoing multiple collisions with nucleons. During this stage it can acquire transverse momentum. In the second stage a prehadron is formed which has a very small elastic cross section with the nucleons. In the third stage the prehadron turns into a hadron. For HERMES energies, prehadron elastic scatterings contribute little to $p_\perp$-broadening. The acquired extra $\Delta p_\perp^2$ of hadrons can therefore be deduced entirely from the first stage of quasi free quark propagation with quark-nucleon collisions. We use this model to describe $\pi$-production on Ne, Kr, Xe and compare with the most recent HERMES preliminary data.