Hadron Production in Diffractive Deep-Inelastic Scattering

TL;DR

This paper investigates hadron production in diffractive deep-inelastic scattering at HERA, analyzing various distributions and comparing them with models, revealing dominance of hard gluons in the diffractive exchange at low Q^2.

Contribution

It provides detailed measurements of hadron production characteristics in diffractive DIS and compares them with models, highlighting the role of hard gluons in the process.

Findings

Distributions are consistent with a partonic structure dominated by hard gluons at low Q^2.

Data agree with Monte Carlo predictions and differ from inclusive DIS results.

Results support the gluon-dominated picture of diffractive exchange.

Abstract

Characteristics of hadron production in diffractive deep-inelastic positron-proton scattering are studied using data collected in 1994 by the H1 experiment at HERA. The following distributions are measured in the centre-of-mass frame of the photon dissociation system: the hadronic energy flow, the Feynman-x (x_F) variable for charged particles, the squared transverse momentum of charged particles (p_T^{*2}), and the mean p_T^{*2} as a function of x_F. These distributions are compared with results in the gamma^* p centre-of-mass frame from inclusive deep-inelastic scattering in the fixed-target experiment EMC, and also with the predictions of several Monte Carlo calculations. The data are consistent with a picture in which the partonic structure of the diffractive exchange is dominated at low Q^2 by hard gluons.