[en] Positive pion-proton interactions in the incident beam momentum range 0.6 - 1.4 GeV/c have been studied. The data processing system, with details of modifications to improve the on-line measuring system, is described fully. Elastic scattering, which accounts for a significant fraction of the events, has been studied and the elastic differential cross-sections extracted. Single pion production final states are analysed in terms of quasi-two body contributions plus non-resonant phase-space. Cross-sections for a Δ⁺⁺ (1236) and rho⁺ (770) production are compared with those from other experiments. The centre of mass angular distribution of the quasi-two body final state PI⁰Δ⁺⁺ (1236) is analysed in terms of Legendre polynomials. The connection with contributing partial waves is discussed and a strong F-wave contribution is noted. A study is made of possible one particle exchange contributions in the production of the rho⁺ (770) rho and PI⁰Δ⁺⁺ (1236) final states. A significant contribution from PI-exchange is noted for the case of rho⁺ production in agreement with higher energy experiments. The development of the isobar model and associated angular momentum formalisms for a three body final state is discussed. A program based on the Deler-Vallada formalism has been checked and the results of a partial wave analysis using this formalism are given and compared with the expectations of a model based on the symmetry group SU(6)sub(W). (U.K.)

[en] Prospects for the existence and detection of massive stable particles are considered. We briefly review some previously postulated massive stable candidates and analyze in some detail the possibility that particles containing the new h quark from E₆ be stable, while satisfying cosmological bounds. The experimental requirements for the detection of massive long-lived particles using a time of flight (TOF) system are examined in the context of a Snowmass 1986 ''realistic'' detector for the SSC

[en] The authors present here a new calorimeter design based on small scintillator tiles, lead absorber and wavelength shifting fiber readout. They have addressed all the major issues in SSC calorimetry and have developed a design with many advantageous features. It has been well demonstrated that the best resolution is obtained for a compensated calorimeter. It is also well known how such compensation may be achieved by a suitable choice of active and passive materials and their relative thickness. One such choice is that of lead and scintillator for which the best thickness ratio is 4:1. This selection has been used in the development of the so-called spaghetti calorimeter (SPACAL) discussed at this workshop. The relative merits of this and many other designs (Liquid Argon, Warm Liquids, Silicon, ...) have been the subject of much discussion at SSC workshops from which a number of critical issues have emerged for each design. In the present paper, they have addressed the issues raised in the SPACAL design and proposed an alternative, improved design. The SPACAL represents a significant step forward in calorimeter design, but there are always areas which can be improved in any design when it is subjected to detailed study. Specifically they have considered the areas of energy resolution, channeling, projective towers/calibration, longitudinal segmentation, and radiation sensitivity. They will now discuss each of these areas in turn

[en] We have studied the production and detection of several types of new particles at the Superconducting Super Collider (SSC) and at three possible upgrades of the Fermilab Tevatron Collider. We compare the physics potential of the SSC with that of an upgraded collider, and we discuss in depth the relative capabilities of the three Tevatron Collider upgrades. From a physics standpoint, we suggest that one of the proposed upgrades has several advantages. 34 refs., 21 figs., 5 tabs

[en] We describe the use of the multiprocessor control system. UFMulti, for a variety of high energy physics applications

[en] We present here a new calorimeter design based on small scintillator tiles, lead absorber and wavelength shifting fiber readout. We have addressed all the major issues in SSC calorimetry and have developed a design with many advantageous features. It has been well demonstrated that the best resolution is obtained for a 'compensated' calorimeter. It is also well known how such compensation may be achieved by a suitable choice of active and passive materials and their relative thickness. One such choice is that of lead and scintillator for which the best thickness ratio is 4:1. This selection has been used in the development of the so-called spaghetti calorimeter (SPACAL) discussed at this workshop. The relative merits of this and many other designs have been the subject of much discussion at SSC workshops from which a number of critical issues have emerged for each design. In the present paper, we have addressed the issues raised in the SPACAL design and proposed an alternative, improved design. The SPACAL represents a significant step forward in calorimeter design, but there are always areas which can be improved in any design when it is subjected to detailed study. Specifically we have considered the areas of energy resolution, channeling, projective towers/calibration, longitudinal segmentation, and radiation sensitivity. We will now discuss each of these areas in turn. 5 refs., 9 figs

[en] The interacting boson model is generalised by the introduction of an np-boson which makes the model isospin invariant. A qualitative application is made to the sd-shell. (orig.)

[en] Autodetachment spectroscopy, a technique for studying molecular anions, has been applied in the past using color-center lasers or visible dye lasers. In the present work, the technique has been extended to employ a relatively weak diode laser. Laser radiation drives an infrared vibrational-rotational transition in the molecular anion NH . The vibrationally excited anion autodetaches, and the resulting fast neutral is detected. The P₁ (6.5,e- > e) transition in the fundamental (1 < -0) band of NH has been observed near 2806 cm^-1 with a signal to noise ratio of 15:1 with a 30-s averaging time. The present experiment has fewer than 500 ions of a single quantum state in the apparatus at once, interacting with 5 microwatts of laser power. Future instrumental improvements can yield orders of magnitude improvement in sensitivity

[en] We present the results of an energy-independent partial-wave analysis of the reaction π⁺p → ππN at nine c.m. energies between 1400 and 1700 MeV. New bubble chamber data from the Cambridge-Imperial College-Westfield College Collaboration were fitted, together with earlier data from Oxford, using the isobar model in a maximum likelihood fitting program. The isobars used were Δ(1236), N*(1470) and rho(770) and allowance was made for an incoherent contribution from an I = 2 s-wave phase shift produced by one-pion exchange in the t-channel. The results of this analysis are compared with the predictions of symmetry schemes. The rho₁N amplitudes of the S₃₁ and D₃₃ members of the (70,1^-) multiplet are clearly observed and their signs unambiguously determined for the first time. Structure in the P₃₁ wave is discussed in relation to recent claims of a low mass resonance. Possible explanations of the complicated behaviour of the P₃₃ wave are discussed; its N*(1470)π decay is observed for the first time. (orig.)

[en] We have studied hypercharge exchange in two pairs of line-reversed reactions at 7 GeV/c incident beam momentum in a triggered bubble chamber experiment at the SLAC Hybrid Facility. The experiment was carried out with the particular object of testing the predictions of exchange degeneracy using the same apparatus. We present differential and total cross sections for the reactions π⁺p → K⁺Σ⁺, K^-p → π^-Σ⁺ and π⁺p → K⁺Y*⁺(1385), K^-p → π^-Y*⁺(1385) from a π⁺ exposure of sensitivity 150 events/μb and a K^- exposure of 100 events/μb. In each case we have measured the polarization of the final-state hyperon for /t/ < 1.0 (GeV/c)² by direct observation of its decay in the bubble chamber. We present results from an amplitude analysis of the Y*(1385) reactions and find agreement with the predictions of the additive quark model. The Σ⁺ polarization data are consistent with weal exchange degeneracy but the predicted equality of the differential cross section is not observed. (orig.)