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Production properties of K*(892)± vector mesons and their spin alignment as measured in the NOMAD experiment
(2006)The European Physical Journal CFirst measurements of K⋆(892)± mesons production properties and their spin alignment in νμ charged current (CC) and neutral current (NC) interactions are presented. The analysis of the full data sample of the NOMAD experiment is performed in different kinematic regions. For K⋆+ and K⋆− mesons produced in νμ CC interactions and decaying into K0π± we have found the following yields per event: (2.6±0.2(stat.)±0.2(syst.))% and (1.6±0.1(stat ...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 -
Results of the first performance tests of the CMS electromagnetic calorimeter
(2006)The European Physical Journal CPerformance tests of some aspects of the CMS ECAL were carried out on modules of the "barrel" sub-system in 2002 and 2003. A brief test with high energy electron beams was made in late 2003 to validate prototypes of the new Very Front End electronics. The final versions of the monitoring and cooling systems, and of the high and low voltage regulation were used in these tests. The results are consistent with the performance targets including ...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 -
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 -
Search for a narrow baryonic resonance decaying to Ks0 p or Ks0 over(p, ̄) in deep inelastic scattering at HERA
(2006)Physics Letters BA search for a narrow baryonic resonance decaying to Ks0 p or Ks0 over(p, ̄) is carried out in deep inelastic ep scattering with the H1 detector at HERA. Such a resonance could be a strange pentaquark Θ+, evidence for which has been reported by several experiments. The Ks0 p and Ks0 over(p, ̄) invariant mass distributions presented here do not show any significant peak in the mass range from threshold up to 1.7 GeV. Mass dependent upper ...Journal Article -
Reconstruction of the signal amplitude of the CMS electromagnetic calorimeter
(2006)The European Physical Journal CThe amplitude of the signal collected from the PbWO4 crystals of the CMS electromagnetic calorimeter is reconstructed by a digital filtering technique. The amplitude reconstruction has been studied with test beam data recorded from a fully equipped barrel supermodule. Issues specific to data taken in the test beam are investigated, and the implementation of the method for CMS data taking is discussed.Journal Article