The H1 backward calorimeter BEMC and its inclusive electron trigger

A sandwich type lead-scintillator electromagnetic calorimeter with wavelength shifter optical readout has been successfully operated at the DESY ep collider HERA in the H1 detector for three years. The mechanical design of the calorimeter together with the associated electronics and the inclusive electron trigger as well as its performance and stability in test beams and at the ep collider HERA are described in detail. (orig.)26 refs.Available from TIB Hannover: RA 2999(95-177) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Bose-Einstein correlations in deep inelastic e p scattering at HERA

Two-particle correlations in invariant mass are studied separately for like-sign and unlike-sign charged particles produced in deep inelastic positron-proton scattering in a new kinematical domain. The data were taken with the H1 detector at the HERA storage ring in 1994, in which 27.5 GeV positrons collided with 820 GeV protons at a centre of mass energy sqrt{s}=300 GeV. The observed enhancement of the like-sign correlations at low invariant masses is related to the dimensions of the hadronic source. The data are compared to different QCD models where the hadronization is performed with the string-fragmentation model. Results are presented for the first time separately for diffractive and non-diffractive scattering, in domains of four-momentum transfer, Bjorken-x, and hadronic center of mass energy, and in intervals of charged particle multiplicity. The observed source radii do not differ strongly from those measured in lower energy lepton-nucleon inelastic scattering, and e^+e^- annihilation.Comment: 36 pages, 10 Figure

Photoproduction of K"0 and #LAMBDA# at HERA and a comparison with deep inelastic scattering

Inclusive K"0 and #LAMBDA# 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 < p_t < 5 GeV. The production rates as a function of p_t and center of mass rapidity are compared to those obtained in deep inelastic scattering at left angle Q"2 right angle = 23 GeV"2. A similar comparison is made of the rapidity spectra of charged particles. The rate of strangeness photoproduction is compared with pp measurements. The observations are also compared with next-to-leading order QCD calculations and the predictions of a Monte Carlo model. (orig.)SIGLEAvailable from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman