Measurement of Charged Particle Spectra in Deep-Inelastic ep Scattering at HERA

TL;DR

This paper reports measurements of charged particle spectra in deep-inelastic electron-proton scattering at HERA, covering low Q^2 and x, and compares the results with various Monte Carlo models to test hadronisation and parton evolution theories.

Contribution

It provides detailed charged particle density measurements in a new kinematic range and compares them with multiple Monte Carlo predictions, enhancing understanding of hadronisation.

Findings

Charged particle densities vary with pseudorapidity and transverse momentum.

Data show discrepancies with some Monte Carlo models, indicating areas for model improvement.

Results extend the kinematic coverage of previous measurements.

Abstract

Charged particle production in deep-inelastic ep scattering is measured with the H1 detector at HERA. The kinematic range of the analysis covers low photon virtualities, 5 < Q^2 < 100 GeV^2, and small values of Bjorken-x, 10^{-4} < x < 10^{-2}. The analysis is performed in the hadronic centre-of-mass system. The charged particle densities are measured as a function of pseudorapidity (eta^*) and transverse momentum (p_T^*) in the range 0< \eta^* < 5 and 0< p_T^* < 10$ GeV differentially in x and Q^2. The data are compared to predictions from different Monte Carlo generators implementing various options for hadronisation and parton evolutions.