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Mark III results from SPEAR

Description: First results from the MARK III detector at SPEAR are presented based on 2.7 million J/psi decays. The eta/sub c/ is observed in three modes, J/psi ..-->.. ..gamma..eta/sub c/, (eta/sub c/ ..-->.. rho anti rho, eta..pi../sup +/..pi../sup -/, and phi phi). Using the phi phi mode, the eta/sub c/ spin-parity is determined to be 0/sup -/. The known radiative J/psi decays J/psi ..-->.. ..gamma..f(f ..-->.. ..pi../sup +/..pi../sup -/), ..gamma..eta'(eta' ..-->.. ..gamma..rho/sup 0/, eta..pi../sup +/.… more
Date: November 1, 1983
Creator: Toki, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of the hadronic cross section in electron-positron annihilation

Description: This thesis describes the most precise measurement to date of the ratio R, the hadronic cross section in lowest order electron-positron annihilation to the cross section for muon pair production in lowest order electron-positron annihilation. This experiment is of interest because R is a fundamental parameter that tests in a model independent way the basic assumptions of strong interaction theories. According to the assumptions of one of these theories the value of R is determined simply from t… more
Date: November 1, 1983
Creator: Clearwater, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Data Acquisition for a Large Neutrino Detector

Description: A hierarchical, distributed intelligence data acquisition system which has been used for the past two years in neutrino experiments at Brookhaven National Laboratory is described. Performance characteristics and the nature of problems encountered in bringing the system to maturity are discussed and some generalizations of the experience are suggested.
Date: January 1, 1983
Creator: Ahrens, L. A.; Aronson, S. A. & Connolly, P. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Detecting heavy quarks

Description: In this exercise we examine the performance of a detector specifically configured to tag heavy quark (HQ) jets through direct observations of D-meson decays with a high resolution vertex detector. To optimize the performance of such a detector, we assume the small diamond beam crossing configuration as described in the 1978 ISABELLE proposal, giving a luminosity of 10/sup 32/ cm/sup -2/ sec/sup -1/. Because of the very large backgrounds from light quark (LQ) jets, most triggering schemes at thi… more
Date: January 1, 1983
Creator: Benenson, G.; Chau, L. L.; Ludlam, T.; Paige, F. E.; Platner, E. D.; Protopopescu, S. D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Operation of the AFS at L = 1. 4 x 10/sup 32/ cm/sup -2/ sec/sup -1/: a first look at data at high luminosity from the CERN ISR. [Axial Field Spectrometer]

Description: In December 1982 a run was made at the CERN ISR which utilized the superconducting low beta quadrupoles in intersection I8 at the ISR and achieved a luminosity of 1.4 x 10/sup 32/ cm/sup -2/ sec/sup -1/ for 26 x 26 GeV pp collisions. At this luminosity the mean time between inelastic collisions is about 200 ns. A comparison run was also made at the same energy with a luminosity of 3.0 x 10/sup 30/ cm/sup -2/ sec/sup -1/. The luminosity under normal running conditions is typically 1.5 x 10/sup 3… more
Date: January 1, 1983
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Dimethylether: a low velocity, low diffusion drift chamber gas

Description: There are two main motivations to look for a low electron mobility gas: the first is that a low drift velocity relaxes the need to measure drift times with nanosecond (or even subnanosecond) precision; the second is that (in an ideal drift geometry), the capability of resolving two closely spaced tracks depends upon the ratio of electron mobility to ion mobility ..mu../sub e//..mu../sub i/. Since ..mu../sub i/ is rather constant, the way to separate two tracks is to slow down the electrons. Man… more
Date: January 1, 1983
Creator: Villa, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status and future plans for the Mark II detector at SLAC

Description: In this brief talk, I report on three subjects. First the present status of PEP, where there has been a very large increase in the luminosity in the past five months. Next, the present status of the Mark II detector, whose secondary vertex detector constitutes a very important part of the physics which our collaboration is doing at PEP. Finally, I review the design of the upgraded Mark II Detector which will be used at the Stanford Linear Collider (SLC).
Date: April 1, 1983
Creator: Perl, Martin L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Search for the best timing strategy in high-precision drift chambers

Description: Computer simulated drift chamber pulses are used to investigate various possible timing strategies in the drift chambers. In particular, the leading edge, the multiple threshold and the flash ADC timing methods are compared. Although the presented method is general for any drift geometry, we concentrate our discussion on the jet chambers where the drift velocity is about 3 to 5 cm/..mu..sec and the individual ionization clusters are not resolved due to a finite speed of our electronics.
Date: June 1, 1983
Creator: Va'vra, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Operation of the Brookhaven MPS II Facility

Description: The BNL Multiparticle Spectrometer has recently been equipped with a set of narrow cell drift chambers employing a novel, compact, inexpensive, readout scheme. This has given an order of magnitude improvement in beam rate as well as better spatial resolution. Two experiments have been completed in the first year of operation, a good test of the system. This type of a drift chamber arrangement is ideal for use at high luminosity hadron colliders.
Date: January 1, 1983
Creator: Etkin, A.; Foley, K. J. & Longacre, R. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Inclusive lepton production in hadronic events from e/sup +/e/sup -/ annihilation at 29 GeV

Description: We have measured the production rates of prompt electrons and muons in hadronic events from e/sup +/e/sup -/ annihilation at 29 GeV. The inclusive rate per hadronic event for leptons with total momenta greater than 2 GeV/c is determined to be (0.033 +- 0.003 +- 0.012) for electrons and (0.037 +- 0.005 +- 0.008) for muons. We measure the longitudinal and transverse momentum spectra of these leptons. The harder transverse momentum spectrum of leptons from bottom and charm quark relative to charm … more
Date: October 1, 1983
Creator: Nelson, M.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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MPS II drift-chamber system

Description: A description is given of a drift-chamber system that has very good resolution and beam rate capabilities in a compact and reasonably priced package.
Date: January 1, 1983
Creator: Eiseman, S.; Etkin, A. & Foley, K.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of quark fragmentation at 29 GeV

Description: The study of multi-particle final state in high-energy reactions has a long history. Detailed studies of hadronic interactions at Fermilab and at the CERN ISR have shown that particles are emitted in clear jets of hadrons along the beam directions. For the highest energies, a small fraction of events contains large-angle jets originating from hard collisions, in addition to the beam and target fragmentation products. The clearest observation of jets has been in high-energy e/sup +/e/sup -/ reac… more
Date: January 1, 1983
Creator: Ahlen, S.; Akerlof, C.; Baranko, G.; Beltrami, I.; Bender, D.; Baringer, P. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement and simulation of the drift pulses and resolution in the micro-jet chamber

Description: We have tested a prototype of a micro-jet chamber, using both a nitrogen laser and a 10GeV electron beam. The achieved resolution in the particle beam was sigma = 18..mu..m for a lmm impact parameter and 22..mu..m when averaging over the entire beam profile. The experimental results were compared to a Monte Carlo program which simulates the pulse shapes and resolution in drift chambers of any geometry. The main emphasis in our simulation analysis was to study various strategies for drift chambe… more
Date: January 1, 1983
Creator: Va'vra, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design of a lead-glass drift calorimeter with MWPC detection

Description: A drift collection calorimeter having a combined radiator and field-shaping structure made of lead-glass tubing is described. A high-resistance metallic layer is formed by reduction of the lead oxide at the surface of the glass and forms a continuous voltage divider for drift-field shaping. The energy resolution of such a calorimeter is modeled, for several configurations, by the Monte Carlo technique.
Date: February 1, 1983
Creator: Perez-Mendez, V.; del Guerra, A.; Mulera, T.; Hirayama, H. & Nelson, W. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stereo: cylindrical drift chamber for muon decay experiments at LAMPF

Description: A stereo, cylindrical drift chamber has been built for use in a search for rare decay modes of the muon at LAMPF. This chamber (part of the Crystal Box detector) has 728 cells on 8 concentric annuli at alternating angles of 10/sup 0/ to 16/sup 0/ from the chamber axis and with radii from 105 to 220 mm. The basic cell cross section is (9 x 10) mm/sup 2/ and the inter-layer spacing is 4.7 mm. Preliminary results show the single-wire efficiencies to be greater than 99%. Based on results obtained f… more
Date: January 1, 1983
Creator: Bolton, R. D.; Carlini, R. D.; Cooper, M. D.; Frank, J. S.; Hart, V. E.; Matis, H. S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Concept of a solid-state drift chamber

Description: The operation of a solid state drift chamber is described, and its use in a high rate, high multiplicity environment is discussed. The Solid State Drift Chamber (SSDCH) is a thin wafer of a high purity n-type silicon (few cm/sup 2/ x a few hundreds ..mu..m thick) with a single small-area, small-capacitance anode readout. The drift voltage is supplied to an array of drift electrodes on both sides of the wafer to produce a uniform drift field parallel to the surface of the wafer and to ensure the… more
Date: March 1, 1983
Creator: Gatti, E. & Rehak, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Gas-mixing system for drift chambers using solenoid valves

Description: We describe an inexpensive system for mixing argon and ethane drift chamber gas which is used for the E-605 experiment at Fermilab. This system is based on the idea of intermittent mixing of gases with fixed mixing flow rates. A dual-action pressure switch senses the pressure in a mixed gas reservoir tank and operates solenoid valves to control mixing action and regulate reservoir pressure. This system has the advantages that simple controls accurately regulate the mixing ratio and that the mix… more
Date: April 1, 1983
Creator: Cooper, William E.; Sugano, Katsuhito & Trentlage, Donald B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tau and B lifetime measurements from the MARK II

Description: Measurement of the tau lifetime checks whether the tau couples to the charged weak current with the same universal coupling strength as the e and ..mu... The lifetime of bottom hadrons measures the weak coupling between the bottom quark and the charm and up quarks. Measurements of these lifetimes have been made with the MARK II detector at the e/sup +/e/sup -/ storage ring PEP at 29.0 GeV center-of-mass energy at the Stanford Linear Accelerator Center.
Date: August 1, 1983
Creator: Hanson, Gail G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Calibration of the high resolution spectrometer barrel calorimeter at PEP

Description: The High-Resolution Spectrometer (HRS) is a general-purpose detector for the study of high-energy electron-positron collisions. The HRS has been in data-taking operation since early 1982. This report covers the calibration of the barrel shower counter system. The barrel system consists of 40 modules placed in a circular arch having a mean radius of 2.1 m. Each module covers an azimuthal wedge of 9 degrees and has an active length of 3.0 m. There are three independent sections: (1) an inner sand… more
Date: January 1, 1983
Creator: Loos, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ionization statistics and diffusion: analytical estimate of their contribution to spatial resolution of drift chambers

Description: The spatial resolution of a drift chamber often is the foremost design parameter. The calculation described here - a design tool - permits us to estimate the contributions of ionization statistics and diffusion to the spatial resolution when actually sampling the drift pulse waveform. Useful formulae are derived for the cylindrical and jet-chamber cell geometries.
Date: January 1, 1983
Creator: Tarnopolsky, G. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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