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Proposal for Research and Development: Vertexing, Tracking, and Data Acquisition for the Bottom Collider Detector

Description: The authors propose a program of research and development into the detector systems needed for a B-physics experiment at the Fermilab p-{bar p} Collider. The initial emphasis is on the critical issues of vertexting, tracking, and data acquisition in the high-multiplicity, high-rate collider environment. R and D for the particle-identification systems (RICH counters, TRD's, and EM calorimeter) will be covered in a subsequent proposal. To help focus their efforts in a timely manner, they propose the first phase of the R and D should culminate in a system test at the C0 collider intersect during the 1990-1991 run: a small fraction of the eventual vertex detector would be used to demonstrate that secondary-decay vertices can be found at a hadron collider. The proposed budget for the r and D program is $800k in 1989, $1.5M in 1990, and $1.6M in 1991.
Date: January 1, 1989
Creator: Castro, H.; Gomez, B.; Rivera, F.; Sanabria, J.-C.; U., /Los Andes; Yager, P. et al.
Partner: UNT Libraries Government Documents Department

Proceedings of the workshop on triggering and data acquisition for experiments at the Supercollider

Description: This meeting covered the following subjects: triggering requirements for SSC physics; CDF level 3 trigger; D0 trigger design; AMY trigger systems; Zeus calorimeter first level trigger; data acquisition for the Zeus Central Tracking Detector; trigger and data acquisition aspects for SSC tracking; data acquisition systems for the SSC; validating triggers in CDF level 3; optical data transmission at SSC; time measurement system at SSC; SSC/BCD data acquisition system; microprocessors and other processors for triggering and filtering at the SSC; data acquisition, event building, and on-line processing; LAA real-time benchmarks; object-oriented system building at SSC; and software and project management. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
Date: April 1, 1989
Creator: Donaldson, R.
Partner: UNT Libraries Government Documents Department

Report of the Task Force on detector Research and Development for the Superconducting Super Collider

Description: This report contains a: Report of the working group on tracking devices; report of the working group on calorimetry; report of the working group on muon, electron and hadron identification; report of the working group on electronics, triggering, data acquisition and computing; report of the working group on superconducting magnets; and report of the working group on Monte Carlo development.
Date: June 1, 1986
Partner: UNT Libraries Government Documents Department

Particle identification in ultrarelativistic nuclear collisions

Description: The role of particle identification (PID) in both fixed-target and colliding-beam studies of ultrarelativistic nuclear (URN) collisions is examined. The demands placed on the PID systems by peculiarities of URN collisions, such as large multiplicities and the need for simultaneous measurement of a number of observables, are discussed. A variety of PID techniques are reviewed, with emphasis on their applicability and efficiency in the environment of such collisions. Two examples of PID as incorporated into existing fixed-target nuclear-beam experiments are presented. 18 refs., 5 figs.
Date: April 1, 1986
Creator: DiGiacomo, N.J.
Partner: UNT Libraries Government Documents Department

Particle identification for beauty physics

Description: We look briefly at the requirements for particle identification for possible beauty experiments at the Tevatron, both in the fixed target and the collider mode. Techniques presently in use in high energy physics experiments, and under development, should make sensitive experiments feasible. However, in all cases the present state of the art must be advanced to meet the necessary requirements for segmentation andor rate capability. The most fundamentally difficult challenges appear to be the efficient tagging of soft electrons (for the collider experiment) and the need to handle interaction rates up to /approximately/ 10/sub 9/ HZ in the fixed target mode. In both cases we can find ''in principle'' demonstrations that the requirements can be met. We have considered only the most basic prooperties of detectors, however, and the real answers will come from careful studies of details. 20 refs., 10 figs.
Date: January 1, 1987
Creator: Ludlam, T.
Partner: UNT Libraries Government Documents Department

Performance of a uranium liquid argon calorimeter

Description: We present results on the performance of a uranium and liquid argon calorimeter in the NW test beam at Fermilab. We describe the calorimeter, and discuss its performance with electrons, pions and muons from 10 GeV to 150 GeV. The performance perameters measured include response, linearity, resolution, compensation, and e/..pi.. separation.
Date: January 1, 1986
Creator: Tuts, P.M.
Partner: UNT Libraries Government Documents Department

Identifying heavy Higgs bosons

Description: Two techniques for identifying heavy Higgs bosons produced at SSC energies are discussed. In the first, the Higgs boson decays into ZZ, with one Z decaying into an e-pair or ..mu..-pair and the other into a neutrino pair. In the second, the production of the Higgs boson by WW fusion is tagged by detecting the quarks that produced the bremsstrahlung virtual W's. The associated Higgs decay is identified by one leptonic and one hadronic decay. Both methods appear capable of finding a heavy Higgs boson provided the SSC design parameters are achieved. 16 refs., 2 figs., 2 tabs.
Date: June 1, 1986
Creator: Cahn, R.N.
Partner: UNT Libraries Government Documents Department

Recent results from DELCO

Description: DELCO is a magnetic spectrometer with Cerenkoc, Time-of-Flight (TOF) and shower counters for particle identification. It is located in IR8 of the PEP storage ring. Data have been obtained at a center of mass energy, ..sqrt..s, of 29 GeV. We report on: (1) the fraction of P, K, ..pi.. in hadronic events; (2) the observation of direct electron signals; and (3) the measurement of D* fragmentation function and its total cross-section. 8 references.
Date: November 1, 1983
Creator: Atwood, W.B.; Baillon, P.H.; Barish, B.C.; Bonneaud, G.R.; DeStaebler, H.; Donaldson, G.J. et al.
Partner: UNT Libraries Government Documents Department

Preliminary spectrometer results from E-802

Description: This report presents preliminary spectrometer results from the E-802 experiment at the Tandem-AGS accelerator complex at Brookhaven National Laboratory. The data presented were taken in late April of 1987 using a 14.5 GeV/c per nucleon /sup 28/Si beam from the AGS. Data were obtained for a variety of targets and spectrometer settings, but we present here the analysis of data for one target-angle combination: a Au target wth the spectrometer spanning 14/sup 0/ to 28/sup 0/ in the lab. At this energy the laboratory mid-rapidity angle in N-N collisions is approx. = 21/sup 0/. A higher K/sup +//..pi../sup +/ ratio than K/sup -//..pi../sup -/ ratio is observed. The primary goal for the E-802 experiment is to measure inclusive particle spectra with good particle identification (PID) over a wide range of rapidity and transverse momentum, and to correlate these spectra with observables that characterize the vent topology such as total charged particle multiplicity and neutral transverse energy. The acceptance of the spectrometer is large enough to span roughly one unit of rapidity in a single setting and is adequate for studies of particle-particle correlations. The spectrometer is also sufficiently compact (6.5 m in length) to allow a reasonable fraction of low momentum pions and kaons to traverse the entire particle identification system. Segmentation for the tracking and PID counters was designed to handle particle multiplicities up to 15 through the spectrometer and 20 in front of the magnet.
Date: January 1, 1987
Creator: Miake, Y. & Stephans, G.S.F.
Partner: UNT Libraries Government Documents Department

Higgs hunting

Description: The phenomenology of the Higgs boson in the standard SU(2) x U(1) electroweak model is reviewed. We compare signatures and cross sections for various Higgs production mechanisms: (1) toponium radiative decay (xi ..-->.. H/sup 0/..gamma..); (2) gluon gluon fusion (gg ..-->.. H/sup 0/); (3) Compton-like process (gc ..-->.. H/sup 0/c); and (4) bremsstrahlungs at Z/sup 0/ resonance. It is argued that new detection techniques for heavy particle identification could be helpful in triggering the rare Higgs signals from the backgrounds.
Date: January 1, 1982
Creator: Keung, W.Y.
Partner: UNT Libraries Government Documents Department

Status of the expansion of the CYGNUS array at Los Alamos

Description: The CYGNUS air shower array, located in Los Alamos, New Mexico, has been operating since April, 1986. The expansion of the array from 108 to 200 counters is described along with the increase in muon detection area. The new array, to be fully operational by the end of 1989, will have three times the sensitivity to UHE sources. 5 refs., 2 figs.
Date: January 1, 1989
Creator: Berley, D.; Chang, C.Y.; Dingus, B.L.; Goodman, J.A.; Haines, T.J.; Stark, M. et al.
Partner: UNT Libraries Government Documents Department

First experiments with the Plastic Ball

Description: After two and a half years of development and construction, an electronic 4..pi.. detector has been used for the first time in studying relativistic nuclear collisions. This detector complements the visual 4..pi.. detectors like emulsions, AgCl detectors, and the streamer chamber, which have been in use for many years. Only the streamer chamber has the same important feature as the Plastic Ball in being triggerable for specific event types. In a series of experiments with beams of /sup 20/Ne, /sup 40/Ar, and /sup 40/Ca up to energies of 1.05 GeV/u, approximately three million events were measured with various trigger conditions. In contrast to the visual detectors, these events are already totally digitized and ready for immediate analysis. All multiparticle correlations of charged particles are measured in each event and do not have to be determined as an average quantity from two particle inclusive data. Besides the particle identification of the hydrogen and helium isotopes, the Plastic Ball identifies the positive pions. This makes it interesting for the study of pion production, which sets in at around 100 MeV/u incident energy, and has promise to shed some light onto the equation of state of nuclear matter. Besides the analysis of the data in the standard way of selections and of single particle inclusive data, a global analysis is in progress that should allow us to determine the reaction plane, and the event shape in phase space. The operation and general layout of the Plastic Ball are described. (WHK)
Date: March 1, 1982
Creator: Gutbrod, H.H.; Baden, A. & Loehner, H.
Partner: UNT Libraries Government Documents Department

Report of the intermediate-)ital p)/sub perpendicular/ detector group: A beauty spectrometer for the SSC (superconducting super collider)

Description: A ''Beauty Spectrometer'' has been designed for studies of B physics at the SSC. The ultimate goal is a definitive measurement of CP violation in the B system. The spectrometer consists of two stages and occupies one side of an intermediate-luminosity interaction region. An upstream, or intermediate, stage extends from the interaction point to 14 m and covers the angular region from 57 mrad (3.3 degree) to 350 mrad (20 degree). The forward stage extends to 77 m and to angles down to 5.7 mrad. The design includes silicon microstrip detectors, conventional tracking, momentum analysis, and hadron and lepton identification. While no fundamental problems have been found, the detector must deal with unprecedented particles fluxes, trigger rates, and data rates. 11 refs., 10 figs., 5 tabs.
Date: July 1, 1987
Creator: Foley, K.J.; Buchanan, C.D.; Morrison, R.J.; McHugh, S.W.; Witherell, M.S.; Atac, M. et al.
Partner: UNT Libraries Government Documents Department

Monopole search using an accelerator detector

Description: A neutrino detector at the Brookhaven AGS has been used to investigate the feasibility of using an already constructed apparatus for GUT monopole searches. A flux limit (90%CL) of 5.2 x 10/sup -12/ cm/sup -2/ sec/sup -1/ str/sup -1/ was found. The limitations of such an approach are discussed.
Date: December 20, 1983
Creator: Ahrenes, L.A.; Aronson, S.H.; Connolly, P.L.; Erickson, T.E.; Gibbard, B.G.; Montag, M. et al.
Partner: UNT Libraries Government Documents Department

Repetitive MEGAMP per microsecond di/dt pulsers for driving sub-ohm transmission line neutrino particle detectors

Description: With the advent of low-cost honeycomb extrusions of polypropylene sheets, transmission line flash chambers have become highly attractive candidates for large particle detector arrays. This has brought about the need for repetitive pulse systems that must provide exceptionally high peak currents, low levels of spurious radiation, high reliability, and shot life in excess of 10/sup 7/. Each module of 10 flash chambers requires a peak current of 20 kA with a current di/dt greater than 1 MA/..mu..s. The pulser output must develop approx. = 7 kV across a load of 0.5 ..cap omega.. with a pulse width of 500 ns. The complete system will require 40 pulsers run in parallel for a combined current output of 1.4 MA peak with a system di/dt of 40 MA/..mu..s. The repetition rate will be up to 2 Hz. This paper describes the development of such a system, its unique voltage and current diagnostics, and the impact of the physical limitations of present component technology on lifetime, reliability, maintainability, and pulse fidelity.
Date: January 1, 1980
Creator: Krausse, G.J.; Dalton, C.G. & Sarjeant, J.
Partner: UNT Libraries Government Documents Department

Hadron production in e/sup +/e/sup -/ annihilation at. sqrt. s = 29 GeV

Description: Data from the High Resolution Spectrometer at PEP have been used to study the inclusive production of baryons and mesons. Time-of-flight measurements are used to identify the charged hadrons. Neutral hadrons are identified from effective mass peaks in their decay into two charged particles. Cross sections for charged pions, charged and neutral kaons, protons and lambda hyperons are given. Other inclusive production characteristics are presented. The cross section ratios to the point cross section are: R(K/sup 0/) = 5.59 +- 0.19 +- 0.30, and for ..lambda..'s, R(..lambda..) = 0.762 +- 0.052 +- 0.064. The results, when compared to the Lund fragmentation model, give (us/ud)/(s/d) = 0.30 +- 0.10. 17 refs., 11 figs., 6 tabs.
Date: January 1, 1985
Creator: Derrick, M.; Fernandez, E.; Fries, R.; Hyman, L.; Kooijman, P.; Loos, J.S. et al.
Partner: UNT Libraries Government Documents Department

Pion correlations as a function of atomic mass in heavy ion collisions

Description: The method of two pion interferometry was used to obtain source-size and lifetime parameters for the pions produced in heavy ion collisions. The systems used were 1.70 {center dot} A GeV {sup 56}Fe + Fe, 1.82 {center dot} A GeV {sup 40}Ar + KCl and 1.54 {center dot} A GeV {sup 93}Nb + Nb, allowing for a search for dependences on the atomic number. Two acceptances (centered, in the lab., at {approximately} 0{degrees} and 45{degrees}) were used for each system, allowing a search for dependences on the viewing angle. The correlation functions were calculated by comparing the data samples to background (or reference) samples made using the method of event mixing, where pions from different events are combined to produce a data sample in which the Bose-Einstein correlation effect is absent. The effect of the correlation function on the background samples is calculated, and a method for weighting the events to remove the residual correlation effect is presented. The effect of the spectrometer design on the measured correlation functions is discussed, as are methods for correcting for these effects during the data analysis. 58 refs., 39 figs., 18 tabs.
Date: November 26, 1989
Creator: Chacon, A.D.
Partner: UNT Libraries Government Documents Department

Inclusive. pi. /sup + -/, K/sup + -/, and p, anti p production in e/sup +/e/sup -/ annihilation at. sqrt. s = 29 GeV

Description: Measurements of ..pi../sup + -/, K/sup + -/ and p, anti p inclusive cross sections and fractions in e/sup +/e/sup -/ annihilation at ..sqrt..s = 29 GeV are presented. The momentum interval covered corresponds to 0.01 < z < 0.90, where z = pp/sub beam/. The analysis is based on approximately 70 pb/sup -1/ of data collected between 1984 and 1986 with the TPC2..gamma.. detector at PEP. Charged particles are identified by a simultaneous measurement of momentum and ionization energy loss (dEdx). The recently upgraded detector's momentum resolution of (..delta..pp)/sup 2/ = (1.5%)/sup 2/ + (0.65% . p (GeVc) )/sup 2/ and a dEdx resolution of typically 3.5% allow the measurements to be extended to higher z than previously reported. 70 refs., 59 figs., 7 tabs
Date: January 1, 1988
Creator: Cowan, G.D.
Partner: UNT Libraries Government Documents Department

Charged hadron production in e/sup /+//e/sup /-// annihilation at. sqrt. s = 29 GeV

Description: We have used data from the Time Projection Chamber at the SLAC storage ring PEP to study the inclusive production of charged hadrons in e/sup /+//e/sup /-// annihilation at a center of mass energy of 29 GeV. Charged particles were identified by simultaneous dEdx and momentum measurements. We present cross sections and particle fractions for ..pi../sup/plus minus//, k/sup + -/, and p(/ovr/p//) as a function of energy, momentum, rapidity, and transverse momentum. We compare the predictions of various hadronization models to the data and note discrepancies at high momentum.
Date: March 1, 1988
Creator: Aihara, H.; Alston-Garnjost, M.; Avery, R.E.; Barbaro-Galtieri, A.; Barker, A.R.; Barnett, B.A. et al.
Partner: UNT Libraries Government Documents Department

Measurement of the response of an SCGl-C scintillation glass array to a 4-14 GeV/c pions

Description: An SCGl-C scintillation glass detector consisting of a 3.5 radiation length SCGl-C active converter followed by scintillation and gas tube hodoscopes and a 4 x 4 array of a 20.5 radiation length SCGl-C counters has been exposed to pions in the 4 to 14 GeV/c momentum range. The response of this detector to pions is compared with the response to electrons of the same momentum in order to distinguish between the two types of particles. Using only longitudinal and tranverse shower development criteria the electrons and pions can be separated such that on average 1.1 x 10/sup -1/ of all pions in the range of 4 to 14 GeV/c would be misidentified as electrons of any energy. If the momentum of the incident particle is known and can be used in the identification technique, this average fraction is reduced to 6.4 x 10/sup -3/ of all pions misidentified as electrons of the same momentum.
Date: January 1, 1984
Creator: Cox, B.; Jenkins, C.M.; Judd, D.J.; Hale, G.; Mazur, P.O.; Murphy, C.T. et al.
Partner: UNT Libraries Government Documents Department

New particles and interactions

Description: It is intended to indicate how multiparticle dynamics might serve as a valuable means of advancing our knowledge down the more fundamental line of elementary particle physics. The point of view is taken that the Standard SU(3) x SU(2) x U(1) Model is well established, and is now ripe to be used as a tool for analyzing physics beyond the Standard Model. The tool kit should include reliable and efficient ways of distinguishing gluon jets from quark jets, and of discriminating between t,b,c and light quark jets. What the author considers to be the most topical physics issues arising from the recent confirmation of the Standard Model are reviewed. These include the need for dynamical principles which go beyond the gauge princple, and in particular a satisfactory mechanism for gauge symmetry breaking. Some of the ideas proposed for solving these problems, such as technicolor and supersymmetry (SUSY), are reviewed, together with some of the experimental tests that can be performed. SUSY is examined in detail, and some ways of looking for sparticles in e/sup +/e/sup -/ and anti pp collisions are discussed. The author tries to emphasize the crucial role to be played by the multiparticle jet tools in resolving some hot physics issues. It is seen in particular that the ability to discriminate heavy quark jets with high efficiency will be important, as will be good calorimetry and the ability to select (veto) events with (out) leptons. 57 references. (WHK)
Date: July 1, 1983
Creator: Ellis, J.
Partner: UNT Libraries Government Documents Department

Test beam results for silicon microstrip detectors with VLSI read-out

Description: A telescope consisting of three silicon microstrip detectors has been tested in a high energy positron beam at SLAC. Each detector has trips with 25 micron pitch and is read out by two 128-channel NMOS integrated circuits (''Microplex''). Results on the signal-to-noise ratio, spatial resolution, and two-track separation are given.
Date: April 1, 1986
Creator: Adolphsen, C.; Litke, A.; Schwarz, A.; Turala, M.; Lueth, V.; Breakstone, A. et al.
Partner: UNT Libraries Government Documents Department

Neutrino-oscillation experiments at Brookhaven National Laboratory

Description: Two groups have submitted major proposals for neutrino oscillation searches at BNL. Both are two detector experiments with a close detector at approx. = 100m and a far detector at approx. = 900m. While the details of the experiments are quite different, both groups expect to obtain nu/sub ..mu../ disappearance limits of delta m/sup 2/sin2 theta approx. = 0.1 - 0.2 for small mass difference and sin/sup 2/2 theta at the few percent level for the most sensitive delta m/sup 2/(approx. = 25eV/sup 2/). Since both detectors are designed to identify electrons as well as muons they expect to obtain significant limits on nu/sub e/ appearance (nu/sub ..mu../ ..-->.. nu/sub e/). Each has received approval for a single detector (Phase I) experiment with the two detector phase (Phase II) still pending. The present status of the single detector experiments is detailed. (WHK)
Date: January 1, 1983
Creator: Ahrens, L.A.; Aronson, S.A.; Connolly, P.L.; Gibbard, B.G.; Maeda, Y.; Murtagh, M.J. et al.
Partner: UNT Libraries Government Documents Department

Track reconstruction of normal muon decays in the LAMPF TPC: one working scheme

Description: A working scheme for track reconstruction of normal muon decays in the LAMPF TPC is here outlined. Muon tracks stopping in the TPC and helical electron tracks from muon decay are both identified and fitted for complete event reconstruction. Because of certain geometrical characteristics of the TPC, novel techniques are deployed to find the tracks. Normal road tracing methods do not work reliably; they are replaced by, among other things, a random search technique that locates the helix's planar projection and a carefully worked-out method for correctly putting each coordinate on its proper turn in the helix.
Date: January 1, 1983
Creator: McKee, R.J.
Partner: UNT Libraries Government Documents Department