Measurement of the proton structure function F2(x, Q2) with the H1 detector at HERA

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Vertex Reconstruction using BPC and CIP in DIS Events

H1-Note 05/93-297info:eu-repo/semantics/publishe

An insight into the determinants of the private R&D investments response to R&D subsidies

info:eu-repo/semantics/publishe

An insight into the determinants of the private R&D investment response to R&D subsidies

info:eu-repo/semantics/nonPublishe

F2 Measurement at x-Values around 10-4, using the Satellite Bunch

H1-note 07/94-369info:eu-repo/semantics/publishe

Proton dissociative ρ and elastic φ electroproduction at HERA

The electroproduction of ρ mesons with proton diffractive dissociation for Q2 > 7 GeV2 and the elastic electroproduction of φ mesons for Q2 > 6 GeV2 are studied in e+p collisions at HERA with the H1 detector, for an integrated luminosity of 2.8 pb-1. The dependence of the cross sections on Pt2 and Q2 is measured, and the vector meson polarisation obtained. The cross section ratio between proton dissociative and elastic production of ρ mesons is measured and discussed in the framework of the factorisation hypothesis of diffractive vertices. The ratio of the elastic cross section for φ and ρ meson production is investigated as a function of Q2. © Springer-Verlag 1997.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Photoproduction of K0 and Λ at HERA and a comparison with deep inelastic scattering

Inclusive K0 and Λ photoproduction has been investigated at HERA with the H1 detector at an average photon-proton center of mass energy of 200 GeV in the transverse momentum range 0.5 < pt < 5 GeV. The production rates as a function of pt and center of mass rapidity are compared to those obtained in deep inelastic scattering at 〈Q2〉 = 23 GeV2. A similar comparison is made of the rapidity spectra of charged particles. The rate of strangeness photoproduction is compared with pp̄ measurements. The observations are also compared with next-to-leading order QCD calculations and the predictions of a Monte Carlo model. © Springer-Verlag 1997.0SCOPUS: re.jinfo:eu-repo/semantics/publishe

Measurement of event shape variables in deep inelastic e p scattering

Deep inelastic e p scattering data, taken with the H1 detector at HERA, are used to study the event shape variables thrust, jet broadening and jet mass in the current hemisphere of the Breit frame over a large range of momentum transfers Q between 7 GeV and 100 GeV. The data are compared with results from e+e- experiments. Using second order QCD calculations and an approach to relate hadronisation effects to power corrections an analysis of the Q dependences of the means of the event shape parameters is presented, from which both the power corrections and the strong coupling constant are determined without any assumption on fragmentation models. The power corrections of all event shape variables investigated follow a 1/Q behaviour and can be described by a common parameter ᾱ0.© 1997 Published by Elsevier Science B.V.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Photo-production of ψ(2S) mesons at HERA

Quasi-elastic (z > 0.95) photo-production of ψ(2S) mesons has been observed at HERA for photon-proton centre-of-mass energies in the range 40 to 160 GeV. The ψ(2S) mesons were identified through their decays to ℓ+ℓ- and to J/ψπ+π-, where the J/ψ subsequently decays to ℓ+ℓ-, the lepton ℓ being either a muon or an electron. The cross-section for quasi-elastic photoproduction was measured to be (18.0 ± 2.8(stat) ± 3.0(syst)) nb at a photon-proton centre-of-mass energy of 80 GeV. The ratio of the ψ(2S) to J/ψ quasi-elastic cross-sections is (0.150 ± 0.027(stat) + 0.022(syst)). © 1998 Elsevier Science B.V.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe