[en] Preliminary large transverse momentum and large transverse energy cross sections of 300 GeV protons measured with a large acceptance calorimeter are presented. Processes other than the scattering of two constituents appear to dominate this deep inelastic hadron scattering process

[en] In this review the identification of ultrarelativistic particles (γ ≥ 1000) by means of transition radiation will be discussed. For this purpose, this electromagnetic phenomenon will be treated in a straightforward way form the theoretical point of view, but without neglecting the formal details useful to establish the main design parameters for transition radiation detectors (TRDs). These parameters will be frequently recalled and discussed while reviewing the detectors in the last sections. A noticeable amount of work has been done in the theory of transition radiation since the first article of V. L. Ginzburg and I.M. Frank in 1946 (1), including very widespread reviews (sec. 2-3) that may help the reader interested in further theoretical or experimental details: in this work papers will be indicated for additional and more complete elements useful for a TRD design. After a general presentation of the transition radiation phenomenon (sects. 1, 2) and relative detectors (sects. 3, 4) the state o f the art of this particle identification technique starting from the pioneeristic applications (sect. 5). to the more recent TRDs (sects. 6,7) will be discussed. In this way it is thought that the research and development done on these detectors examined in a chronological way will result much clearer

No abstract available

[en] Preliminary results on large transverse momentum direct photon and π⁰ production in π^-p, π⁺p and pp collisions at 300 GeV/c are presented. A clear signal for direct photon production is observed in all reactions for transverse momenta P_T > 4 GeV/c. The cross sections are measured up to P_T = 7 GeV/c (x_T = 0.6) in π^-p and up to P_T = 6 GeV/c (x_T=0.5) in π⁺p and pp collisions. At large P_T, the direct photon production cross section is increasing in π^-p collisions relative to π⁺p collisions as expected from valence quark-antiquark annihilations. The π⁰ production cross sections at large P_T are the same in π^-p and π⁺p collisions. They decrease faster with P_T in pp collisions than in πp collisions

[en] A Monte Carlo program to design a transition radiator detector is described. The program provides the possibility to calculate the X-ray yield from radiators of different materials and structures, and analyzes the transition radiation energy release in various gaseous detectors. (orig.)

[en] In this paper we exploit the capability of a transition radiation detector to select different mass particles in a high-energy unseparated beam and to provide a prompt identification signal that can be used as a first level trigger for the physical event acquisition. Various studies on prototypes and measurements on electron/hadron test beams at CERN and BNL are presented: on the basis of the results obtained we show that we can promptly separate electrons from pions starting from 1 GeV/c momentum and we discuss about the possibility to distinguish as well pions from protons in the hundred GeV/c range of momentum at the level of a few percent of particle mis-identification

[en] Preliminary results on large transverse momentum π⁰ and direct photon production in π^-p, π⁺p and pp collisions at 300GeV/c are presented. It was found that the γ/π⁰ cross-section ratio is increasing with increasing p_T for π^-p, π⁺p and pp collisions. No striking difference between the direct photon production cross-section in π^-p and π⁺p collisions has been observed up to p_T=5 GeV/c. 9 refs., 9 figs. (author)

[en] Results on large transverse momentum p/sub T/, direct photon and π⁰ production in π/sup -/p, π/sup +/p and pp collisions at 300 GeV/c are presented. A clear direct photon signal is seen for p/sub T/ > 3 GeV/c. At large p/sub T/ the direct photon production cross section is increasing in π/sup -/p collisions relative to π/sup +/p collisions as expected from valence quark-antiquark annihilations. The cross sections are in good agreement with QCD predictions. Preliminary observations of the production of two direct photons and π⁰ in π/sup -/p collisions are presented

[en] We have designed and tested a transition radiation detector able to select different mass particles in a high-energy unseparated beam and to provide a prompt identification signal that can be used as a first-level trigger for the physical event acquisition. A measurement on electron/hadron test beam at CERN is presented: on the basis of the results obtained we show that we can promptly separate electrons from pions starting from 1 GeV/c momentum and we discuss about the possibility to distinguish as well pions from protons in the hundred GeV/c range of momentum at the level of a few percent of particle mis-identification

[en] Cross sections for inclusive direct photon production in π^-p, π⁺p, and pp collisions at 300 GeV/c are measured at transverse momenta p/sub T/ up to 7 GeV/c (x/sub T/ = 0.6). For π^-p→γX also the rapidity distribution is presented. The cross-section ratio σ(π^-p→γX)/σ(π⁺p→γX) is found to be 1 at p/sub T/ = 4 GeV/c and rises with increasing p/sub T/. This observation signals the occurrence of valence-quark--antiquark annihilation. The results are in good agreement with QCD predictions