Energy flow and charged particle spectrum in deep inelastic scattering at HERA

Global properties of the hadronic final state in deep inelastic scattering events at HERA are investigated. The data are corrected for detector effects and are compared directly with QCD phenomenology. Energy flows in both the laboratory frame and the hadronic centre of mass system and energy-energy correlations in the laboratory frame are presented. Comparing various QCD models, the colour dipole model provides the only satisfactory description of the data. In the hadronic centre of mass system the momentum components of charged particles longitudinal and transverse to the virtual boson direction are measured and compared with lower energy lepton-nucleon scattering data as well as with e+e- dat from LEP. © 1994 Springer-Verlag.0400 auteursSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Hard scattering in gamma p interactions

We report on the investigation of the final state in interactions of quasi-real photons with protons. The data were taken with the H1 detector at the HERA ep collider. Evidence for hard interactions is seen in both single particle spectra and jet formation. The data can best be described by inclusion of resolved photon processess as predicted by QCD. © 1992.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Measurement of the hadronic final state in deep inelastic scattering at HERA

We report on the first experimental study of the hadronic final state in deep inelastic electron-proton scattering with the H1 detector at HERA. Energy flow and transverse momentum characteristics are measured and presented both in the laboratory and in the hadronic center of mass frames. Comparison is made with QCD models distinguished by their different treatment of parton emission

Total photoproduction cross-section measurement at HERA energies

We present first results on the total photoproduction cross section measurement with the H1 detector at HERA. The data were extracted from low Q2 collisions of 26.7 GeV electrons with 820 GeV protons. The γp total cross section has been measured by two independent methods in the γp center of mass energy range from 90 to 290 GeV. For an average center of mass energy of 195 GeV a value of σtot (γp) = 159 ± 7 (stat.) ± 20 (syst.) μb was obtained. © 1993.0320 auteursSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Inclusive charged particle cross sections in photoproduction at HERA

Cross sections are presented for the inclusive production of charged particles measured in electron-proton collisions at low Q 2 with the H1 detector at HERA. The transverse momentum distribution extends up to 8 GeV/ c . Its shape is found to be harder than that observed in p p collisions at comparable centre-of-mass energies √S γp ≈ √S p p ≈ 200 GeV , and also harder than in γp collisions at lower energies √ S γp ≈ 18 GeV. Results from quantum chromodynamics (QCD) calculations agree with the measured transverse momentum and pseudorapidity cross sections

Scaling violations of the proton structure function f2 at small x

An analysis is presented of scaling violations of the proton structure function F2(x,Q2) measured with the H1 detector at HERA in the range of Bjorken x values between x = 3 × 10-4 and 10-2 for four-momentum transfers Q>2 larger than 8.7 GeV2. The structure function F2(x,Q2) is observed to rise linearly with ln Q2. Under the assumption that the observed scaling violations at small x ≤ 0.01 are described correctly by perturbative QCD, an estimate is obtained of the gluon distribution function G(x,Q02) at Q22 = 20 GeV2. © 1994.0320 auteursSCOPUS: ar.jinfo:eu-repo/semantics/publishe

A Search for leptoquarks, leptogluons and excited leptons in H1 at HERA

A direct search for new particles in the H1 experiment at HERA is presented for masses ranging from 35 GeV up to ∼ 250 GeV. The data sample of 24 nb−1 accumulated during the first year of operation was analysed for signatures of scalar and vector leptoquarks, leptogluons, excited electrons and excited neutrinos with flavours of the first generation. No evidence for the production of such particles was found in various possible decay channels. Rejection limits are derived