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[en] In this review an attempt is made to summarize briefly all that is presently known about hadron-nucleus collisions at high energies: hadron-nucleus cross sections, cross sections of multiparticle states produced inside nuclear matter, multiparticle production, production of particles with high transverse momentum and A-dependence of di-muon production by hadrons. (BJ)
[de]In diesem Uebersichtsartikel wird kurz zusammengefasst, was im Augenblick ueber die Hadron-Kernstoesse bei hohen Energien bekannt ist: Hadron-Kern Wirkungsquerschnitte, Wirkungsquerschnitte fuer Vielteilchenzustaende in Kernmaterie, Vielteilchenerzeugung, Produktion von Teilchen mit hohem Transversalimpuls und A-Abhaengigkeit der Dimyonerzeugung durch Hadronen. (BJ)
[en] Future calorimeters and shower maximum detectors at high luminosity colliders need to be highly radiation resistant and very fast. One exciting option for such a detector is a calorimeter composed of a secondary emitter as the active element. Here, we outline the study and development of a secondary emission calorimeter prototype using micro-channel plates (MCP) as the active element, which directly amplify the electromagnetic shower signal. We also demonstrate the feasibility of using a bare MCP within an inexpensive and robust housing without the need for any photo cathode, which is a key requirement for high radiation tolerance. Test beam measurements of the prototype were performed with 120 GeV primary protons and secondary beams at the Fermilab Test Beam Facility, demonstrating basic calorimetric measurements and precision timing capabilities. Using multiple pixel readout on the MCP, we demonstrate a transverse spatial resolution of 0.8 mm, and time resolution better than 40 ps for electromagnetic showers.
[en] Hadronic production of charmonium states such as J/ψ, χc, and ψ' provides valuable tests for the theory of strong interaction, known as Quantum Chromodynamics (QCD), and for related theoretical models. In this thesis the authors analyze data collected by the experiment E672/E706 using 530 GeV/c π- beam incident on Be and Cu targets at Tevatron II, Fermi National Accelerator Laboratory. The experiment was performed at the highest πN center-of-mass energy up to date and very respectable charmonium mass resolution was achieved. The apparatus of the experiment for the 1990 run-period is described. J/ψ mesons are detected in the μ+μ- decay mode. The integrated and differential cross sections of J/ψ hadronic production are measured. The dependence of the cross section on atomic numbers of the targets and on reaction inelasticity are also determined. The χc mesons are detected in the decay mode χc → J/ψγ, with the photon converted to e+e- in the spectrometer. The mass resolution is sufficient to resolve χc1(3508) and χc2(3555). The ψ' mesons are detected in both J/ψπ+π- and μ+μ- decay modes. The fractions of observed J/ψ coming from χc or ψ' decays are measured. From these results, the prompt production cross sections of the charmonium states J/ψ, χc, and ψ' are estimated
[en] We report detection of gamma rays at energies greater than 500 GeV from the direction of Vela pulsar, pulsed with the same period as the radio pulsar PSR 0833-45. The light curve shows two peaks of amplitude 4.4 sigma and 2.5 sigma, separated by 0.42 of the period similar to the observations at lower energies by satellite borne detectors. (orig./WL) 891 WL/orig.- 892 ARA