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A proposal to study particle production spectra and multiplicities in high energy hadron-hadron collisions, and for a beam survey and quark search

Description: We propose an experimental study at the new 500 GeV accelerator of the differential cross-section for particle production in hadron-hadron collisions. The projectile, and the observed single particle, will range over all combinations of positive and negative {pi}, K and p, with momenta extending up to the highest available. Enough of the secondary particle momentum range will be covered to permit us to determine by integration the multiplicity of the produced particle. Single particles will be detected in a simple spectrometer consisting of wire chambers and a small bending magnet. The configuration of the spectrometer components will be variable so that the overall spectrometer length can be kept proportional to the secondary momentum. The momentum resolution {male}P/P = {+-}0.8% and the invariant phase space acceptance P{sup 2}d{Omega}dP/E = 1.3x10{sup -3} (GeV/c){sup 2} will then be the same at all momenta. Particle identification will be by means of threshold Cherenkov counters, with 10{sup 4}: 1 rejection up to at least 250 GeV/c. Our experimental arrangement is thought to be simple and yet powerful, and we propose its use initially with incident protons and a nuclear target for a beam survey and quark search. Subsequent measurements will be carried out with a hydrogen target in a high intensity secondary beam.
Date: June 15, 1970
Creator: Beier, E.W.; Kreinick, D.L.; Weisberg, H. & U., /Pennsylvania
Partner: UNT Libraries Government Documents Department

Development of the OSO-6 high-energy neutron detector and correlation of measured solar neutron fluxes to solar flares

Description: Thesis. The development of a directional high energy (20 to 160 MeV) neutron detector which was flown to satellite altitudes (500 km; circular equatorial orbit) in the NASA Orbiting Solar Observatory (OSO-6) in August 1969 is described. Both the angle of incidence and the energy of the neutron are determined by a proton-recoil telescope (Pilot B scintillation plastic) which provides the source for proton-recoils and defines the dE/dX versus E method for particle identification and energy determination. The telescope is embedded in a scintillation plastic guard counter envelope which eliminates the unwanted charged particle background as well as recoil protons (electrons) whose energies and direction do not satisfy neutron (gamma-ray) detection requirements, respectively. Results from a Monte Carlo calculation indicate that the overall average efficiency within an average angular acceptance of about 29 deg (FWHM) is approximately (2.25 plus or minus 0.113) x 10/sup -4/. The inflight calibration procedure, the main frame data bit error analysis, and the method for determining the orientation of the detector axis in the spacecraft spin plane are described. Results indicate a discrepancy in the measured (0.461 x 10/sup -2/ plus or minus 0.254 x 10/sup -2/ n/cm/sup 2/sec) and theoretical (2 to 70 n/cm/ sup 2/sec) neutron flux es which suggests a lack of basic underatanding of mechanisms leading to high energy neutron production at the sun. (auth)
Date: February 1, 1974
Creator: Young, F.
Partner: UNT Libraries Government Documents Department

Time-of-flight measurements at the LAMPF low-energy pion channel

Description: Particle identification by time-of-flight techniques was carried out using flight paths between two scintillation counters and between one such counter and the 200-MHz rf structure of the primary proton beam striking the meson production target. With the low-energy pion channel at 103 MeV/c, the two- counter technique yielded clean separation of pions, muons, and electrons. At 195 MeV/c, the rf technique measured the energy resolution of the primary proton beam to be as good as 0.14% FWHM. (auth)
Date: March 1, 1974
Creator: Cooper, M.D.
Partner: UNT Libraries Government Documents Department

Energy Spectra of Fragments from Silver and Uranium Bombarded with5.0 GeV Protons

Description: In this third paper in a series in which the characteristics of nuclear fragments produced in the interaction of 5 GeV protons with Ag and U targets were studied by means of dE/dx-E measurements with semiconductor detector telescopes new information was obtained on the energy spectra of light fragments. One set of measurements on fragments from a Ag target involved the use of a two-element telescope incorporating a {Delta}E detector as thin as 16 {micro}m. A new algorithm for processing the {Delta}E and E data to extract particle identification was developed and the resulting particle spectra showed superior resolution for the elements from Li(Z = 3) to S (Z = 16). Segments of the energy spectra of each of these elements were measured at 20{sup o} and, for many of them, also at 45{sup o}, 90{sup o}, 135{sup o} and 160{sup o} to the beam direction. By use of 3-element telescopes and absorbers the high energy part of the energy spectrum for isotopes of He, Li, Be, B, and C ejected from Ag and U targets was measured at 20{sup o}. The measurements extended beyond 300 MeV for {sup 6}Li and {sup 7}Li and to 400 MeV for {sup 7}Be. A distinct high-energy component was found in these cases. The suitability of nuclear evaporation as a description of the emission of the low-energy fragments was tested with two simple theoretical models, one specifying isotropic fragment emission from a moving nucleus at a fixed nuclear temperature and one specifying isotropic fragment emission from a set of moving nuclei with a Maxwellian distribution of excitation energies and forward momenta. The second could describe rather well all the 90{sup o} data, provided a Coulomb barrier 0.4 that of the classical tangent spheres barrier was used. However, the measured intensity in the forward direction ...
Date: August 1, 1972
Creator: Korteling, Ralph G.; Toren, C.R. & Hyde, Earl K.
Partner: UNT Libraries Government Documents Department

Relativistic rise measurement by cluster counting method in time expansion chamber

Description: A new approach to the measurement of the ionization energy loss for the charged particle identification in the region of the relativistic rise was tested experimentally. The method consists of determining in a special drift chamber (TEC) the number of clusters of the primary ionization. The method gives almost the full relativistic rise and narrower landau distribution. The consequences for a practical detector are discussed.
Date: October 1, 1979
Creator: Rehak, P. & Walenta, A.H.
Partner: UNT Libraries Government Documents Department

Cerenkov counters at ISABELLE

Description: Particle mass identification capability will be very important for much of the physics at ISABELLE. It will be required for studying quantum number flow in quark--quark scattering (jet and high P/sub t/ physics), hadronic decays of W's and Z's, and ''onium'' states. It will be essential for detecting and studying ''naked flavor'' states and generally required or at least very useful for most hadronic physics at ISABELLE. The large all-purpose detectors envisioned for ISABELLE require particle identification covering up to 4..pi.. solid angle with high multiplicity capability, high rate capability, insensitivity to high magnetic fields, and large dynamic range (1 to 400 GeV/c). In addition, it would be desirable to have this information for on-line event selection. At present there are only four practical methods for doing charged hadron identification: time-of-flight, dE/dX (ionization sampling), transition radiation, and Cerenkov radiation. All these methods need independent momentum determination and are effective over only limited kinematic ranges. Although the status and foreseeable development of these techniques are discussed at length elsewhere their expected capabilities are summarized in order to compare them with Cerenkov techniques. For the sake of argument a 4..pi.. steradian detector with an inner radius of 2 m is assumed.
Date: January 1, 1978
Creator: Ashford, V.; Etkin, A.; Honma, A.; Kostoulas, I.; Lanou, R. & Watts, T.
Partner: UNT Libraries Government Documents Department

PWCs and drift chambers at ISABELLE

Description: Rate effects in proportional chambers and drift chambers are addressed first. The widely used high-gas-gain chambers would have impaired performance at ISABELLE data rates. Improvement can be expected with lower gas gain, and this possibility is investigated with respect to position and time resolution. Results on chamber lifetime are summarized; space-charge effects, gain saturation, and radiation hardness of electronics are considered. The resolution of drift chambers is discussed in some detail; time resolution, double pulse resolution, and momentum resolution and multiple scattering are included. The expected high multiplicity of tracks from a single event, the high event rates, and the requirement for low gas gain necessitate revision of the methods for measuring the second coordinate. Known methods of two-dimensional point localization are summarized according to spatial accuracy, electronics requirements, and multihit capability. Delay lines, charge division, and cathode strips are considered. Particle identification by means of measurement of the relativistic rise of energy loss by conventional and unconventional means was investigated. 32 references, 3 figures, 4 tables. (RWR)
Date: January 1, 1978
Creator: Okuno, H.; Teramoto, Y. & Wheeler, C.D.
Partner: UNT Libraries Government Documents Department

Mass resolution for lepton pairs at Isabelle

Description: Experiments measuring e/sup +/e/sup -/ and ..mu../sup +/..mu..-pairs will be the principal way of searching at ISABELLE for the Z/sup 0/ and for vector mesons made from new heavy quark-antiquark (Q anti Q ) pairs. Although the best possible mass resolution is clearly of benefit in such experiments, excessive resolution would lead to an unnecessarily large detector. It is believed that a mass resolution of a few percent is appropriate in searching both for the Z/sup 0/ and for new Q anti Q states. However, there are some interesting experiments which would require much better mass resolution, of order 1/4% FWHM. 9 references.
Date: January 1, 1978
Creator: Baltay, C. & Paige, F.E.
Partner: UNT Libraries Government Documents Department

Summary report of neutral detector subgroup

Description: The advantages and disadvantages of calorimeters for use at ISABELLE are discussed including hadron calorimeters, liquid argon calorimeters, uranium scintillator calorimeters, electromagnetic shower detectors, and iron plate calorimeters. A calorimeter is described that is suitable for electromagnetic and hadronic events and is constructed with a front section of narrow Pb strips to start and develop the electromagnetic shower. A section of U towers to contain hadronic showers follows. This calorimeter would shield out U radioactivity and measure the energy and position of all particles except neutrinos and muons. (FS)
Date: January 1, 1977
Creator: Akerlof, C.; Bensinger, J. & Donaldson, G.
Partner: UNT Libraries Government Documents Department

''Conventional'' Cerenkov counters at ISABELLE

Description: Cherenkov counters to be used with ISABELLE are described. The three counters used in the Hadron Spectrometer can be used to identify particles in the range 10 to 40 GeV/c with pions separated from heavier particles down to approximately 3 GeV/c. A longer spectrometer for 400 x 400 GeV operation should also be used. The spectrometers may be used with CO/sub 2/ and H/sub 2/. The range of particle identification of 8 to 60 GeV/c with pions separated from heavier particles down to approximately 5 GeV/c is possible. (FS)
Date: January 1, 1977
Creator: Foley, K J
Partner: UNT Libraries Government Documents Department

Projection chambers and dE/dx at ISABELLE

Description: The ''standard'' luminosity of 2 x 10/sup 32/ is taken as a goal for a device that measures charged particle momenta over a wide solid angle. It appears that a projection chamber is capable of operation in this mode providing care is taken to optimize the geometry with this high flux in mind. Some calculations have indicated that optimism is required but in no direction have the demands on the apparatus appeared to be well beyond those attainable. In addition dE/dx measurements yielding particle identification over the median momentum range, about 2 to 30 GeV/c, are also feasible.
Date: January 1, 1977
Creator: White, D.H.; Benary, O.; Rosenson, L.; Roe, B.; Ditzler, W.R.; Watts, T. et al.
Partner: UNT Libraries Government Documents Department

Charged particle detector system for high rate experiments

Description: A charged particle detector system under development at BNL for use at the Multiparticle Spectrometer (MPS) and eventually at ISABELLE is described. The object is to take full advantage of the position accuracy, resolving time and instantaneous rate capabilities of narrow anode spacing drift-proportional chambers. The system will have position resolution sigma approximately equal to 100..mu.., time resolution approximately equal to 8 ns, detector sensitive time approximately equal to 50 ns, and consecutive particle resolving power of 40 ns per wire. It is planned to implement this system in a large system of 30,000 wires at the MPS and greater than 100,000 wires in ISABELLE experiments. Central to the development of this detector system is the production of two custom integrated circuits.
Date: January 1, 1977
Creator: Platner, E D
Partner: UNT Libraries Government Documents Department

Signals for tau neutrino events in a beam dump experiment

Description: Ways of detecting tau neutrinos emerging from a beam dump are studied. Key signatures are elaborated and contrasted with background arising from muon and electron neutrino interactions. Expected event rates are given for various neutrino spectra. 16 references.
Date: May 1, 1979
Creator: Albright, C.H.; Shrock, R.E. & Smith, J.
Partner: UNT Libraries Government Documents Department

Sensitive method for detecting stable fractional charges on matter. [Proposed apparatus]

Description: The design of an apparatus which will allow direct detection of stable fractional elementary charges if present on matter at the level of 10/sup -24/ per nucleon is described in detail. This method depends upon production of a highly uniform and parallel stream of conductive spheres which are charge analyzed by passage through a static electric deflecting field. 6 references.
Date: June 20, 1979
Creator: Hirsch, G.; Hagstrom, R. & Hendricks, C.
Partner: UNT Libraries Government Documents Department

Coherent pion processes in nuclear collision. [Cross section instabilities, signatures, pion field]

Description: The calculations indicating that pionic instabilities could occur during nuclear collisions are reviewed and specific dynamical effects of such instabilities are discussed. Then experimental signatures of pionic instabilities are considered. The single nucleon inclusive cross section as well as the pion multiplicity distribution are shown not to be sensitive to such instabilities. In particular, no copious pion production is expected. Finally, it is discussed how ..pi../sup -/..pi../sup -/ inclusive cross section can be used as a sensitive tool to measure the degree of coherence of the pion field in nuclear collisions.
Date: April 1, 1978
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Time expansion chamber and single ionization cluster measurement

Description: The time expansion chamber (TEC), a new type of drift chamber, allows the measurement of microscopic details of ionization. The mean drift time interval from subsequent sngle ionization clusters of a relativistic particle in the TEC can be made large enough compared to the width of a anode signal to allow the recording of the clusters separately. Since single primary electrons can be detected, the cluster counting would allow an improved particle separation using the relativistic rise of primary ionization. In another application, very high position accuracy for track detectors or improved energy resolution may be obtained. Basic ionization phenomena and drift properties can be measured at the single electron level.
Date: October 1, 1978
Creator: Walenta, A H
Partner: UNT Libraries Government Documents Department

High resolution magnetic spectrometer for antiproton physics at rest and low energies

Description: A spectrometer is being installed in a high-intensity antiproton beam (LESBII) at the AGS. The beam momentum entering the target will be known to approximately +- /sup 1///sub 2/%. The target is surrounded by a stereoscopic cylindrical drift chamber, and thus the total charge of the event will be measured. Since the vertex will be reconstructed with an accuracy of approximately +- 2 mm, studies of annihilations with high resolution down to approximately 150 MeV/c will be possible. On one side of the target a large-aperture (2.3 x .62 m/sup 2/) magnet covered on both sides with drift chambers and triggering--TOF scintillation counters, will measure particle and ..gamma..-ray energies with high resolution, as well as identify particles. The primary objective is to look for peaks in the ..gamma.. spectra coming from annihilations at rest by converting them in a thin (.05 x/sub 0/) radiator before the magnet. Narrow peaks (< 1 MeV) which are produced with frequencies of approximately 10/sup -3/ or better are expected to be seen as 5 sigma effects. The principle and details of the spectrometer are presented.
Date: January 1, 1978
Creator: Lowenstein, D I; Peaslee, D C; Lewis, R A; Miller, R; Oh, B.Y. Pratap, M.; Smith, G A et al.
Partner: UNT Libraries Government Documents Department