Internal Jet Structure in Dijet Production in Deep-Inelastic Scattering

TL;DR

This paper investigates the internal structure of jets produced in deep-inelastic scattering at HERA, measuring jet shapes and subjet multiplicities, and comparing results with QCD models and photon-photon collision data.

Contribution

It provides detailed measurements of jet substructure in ep collisions and compares these with photon-photon collision data, enhancing understanding of jet formation.

Findings

Jets become more collimated with higher transverse energies.

Jet shapes are similar in ep and photon-photon collisions.

QCD models accurately describe the measured jet structures.

Abstract

The internal jet structure in dijet production in deep-inelastic scattering is measured with the H1 detector at HERA. Jets with transverse energies E(T,breit) > 5 GeV are selected in the Breit frame employing kt and cone jet algorithms in the kinematic region of squared momentum transfers of 10 < Q^2 < 120 GeV^2 and x-Bjorken values of 0.0002 < x < 0.008. Jet shapes and subjet multiplicities are measured as functions of a resolution parameter. The corrected data are well described by QCD models. It is observed that jets are more collimated with increasing transverse jet energies and decreasing pseudo-rapidities, i.e. towards the photon direction. Comparisons with OPAL data show that jet shapes of jets measured in photon-photon collisions are very similar to those measured in ep collisions.