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Study of charm fragmentation into D (* +/-) mesons in deep-inelastic scattering at HERA
(2009)The European Physical Journal CThe process of charm quark fragmentation is studied using D * ± meson production in deep-inelastic scattering as measured by the H1 detector at HERA. The parameters of fragmentation functions are extracted for QCD models based on leading order matrix elements and DGLAP or CCFM evolution of partons together with string fragmentation and particle decays. Additionally, they are determined for a next-to-leading order QCD calculation in the ...Journal Article -
Elastic J/ψ production at HERA
(2006)The European Physical Journal CCross sections for elastic production of J/ψ mesons in photoproduction and electroproduction are measured in electron proton collisions at HERA using an integrated luminosity of 55 pb-1. Results are presented for photon virtualities Q2 up to 80 GeV2. The dependence on the photon-proton centre of mass energy Wγp is analysed in the range 40≤Wγp≤305 GeV in photoproduction and 40≤Wγp≤160 GeV in electroproduction. The Wγp dependences of the ...Journal Article -
Measurement of event shape variables in deep-inelastic scattering at HERA
(2006)The European Physical Journal CDeep-inelastic ep scattering data taken with the H1 detector at HERA and corresponding to an integrated luminosity of 106 pb-1 are used to study the differential distributions of event shape variables. These include thrust, jet broadening, jet mass and the C-parameter. The four-momentum transfer Q is taken to be the relevant energy scale and ranges between 14 GeV and 200 GeV. The event shape distributions are compared with perturbative ...Journal Article -
Inclusive D*± meson cross sections and D*±-jet correlations in photoproduction at HERA
(2007)The European Physical Journal CDifferential photoproduction cross sections are measured for events containing D*± mesons. The data were taken with the H1 detector at the ep collider HERA and correspond to an integrated luminosity of 51.1 pb-1. The kinematic region covers small photon virtualities Q2 < 0.01 GeV2 and photon–proton centre-of-mass energies of 171 < Wγ p < 256 GeV. The details of the heavy quark production process are further investigated in events with one ...Journal Article -
Measurement of F2c[`(c)]F2ccˉ and F2b[`(b)]F2bbˉ at low Q2 and x * using the H1 vertex detector at HERA
(2006)The European Physical Journal CMeasurements are presented of inclusive charm and beauty cross sections in e +p collisions at HERA for values of photon virtuality 12 ≤ Q2 ≤ 60 GeV2 and of the Bjorken scaling variable 0.0002 x ≤ 0.005. The fractions of events containing charm and beauty quarks are determined using a method based on the impact parameter, in the transverse plane, of tracks to the primary vertex, as measured by the H1 vertex detector. Values for the structure ...Journal Article -
Forward jet production in deep inelastic scattering at HERA
(2006)The European Physical Journal CThe production of forward jets has been measured in deep inelastic ep collisions at HERA. The results are presented in terms of single differential cross sections as a function of the Bjorken scaling variable (x Bj ) and as triple differential cross sections d 3σ/dx Bj dQ 2 dp2t,jet, where Q 2 is the four momentum transfer squared and p2t,jet is the squared transverse momentum of the forward jet. Also cross sections for events with a ...Journal Article -
Diffractive deep-inelastic scattering with a leading proton at HERA
(2006)The European Physical Journal CThe cross section for the diffractive deep-inelastic scattering process ep→eXp is measured, with the leading final state proton detected in the H1 Forward Proton Spectrometer. The data analysed cover the range xIP<0.1 in fractional proton longitudinal momentum loss, 0.08<|t|<0.5 GeV-2 in squared four-momentum transfer at the proton vertex, 2<Q2<50 GeV2 in photon virtuality and 0.004<β=x/xIP<1, where x is the Bjorken scaling variable. For ...Journal Article -
Measurement of charm and beauty dijet cross sections in photoproduction at HERA using the H1 vertex detector
(2006)The European Physical Journal CA measurement of charm and beauty dijet photoproduction cross sections at the ep collider HERA is presented. Events are selected with two or more jets of transverse momentum pt jet1(2)>11(8) GeV in the central range of pseudo-rapidity -0.9<ηjet1(2)<1.3. The fractions of events containing charm and beauty quarks are determined using a method based on the impact parameter, in the transverse plane, of tracks to the primary vertex, as measured ...Journal Article -
Deeply virtual Compton scattering and its beam charge asymmetry in e±p collisions at HERA
(2009)Physics Letters BA measurement of elastic deeply virtual Compton scattering γ * p → γ p using e + p and e - p collision data recorded with the H1 detector at HERA is presented. The analysed data sample corresponds to an integrated luminosity of 306 pb -1, almost equally shared between both beam charges. The cross section is measured as a function of the virtuality Q 2 of the exchanged photon and the centre-of-mass energy W of the γ * p system in the ...Journal Article -