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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

Searching for supersymmetry at the SSC

Description: Supersymmetric (SUSY) models have generated increasing amounts of attention in recent years as a means of understanding the roles of scalar particles in a field theory. Since supersymmetry connects fermions and bosons in a natural framework, theorists are hopeful that it will reduce the freedom surrounding fermions and scalars in the Weinberg-Salam model. No satisfactory model exists at this time, but the structure of the supersymmetric algebra is sufficiently attractive to warrant a serious study of its consequences. It is possible to make a great many predictions which are independent of the choice of a specific model. In this report we make a detailed attempt to study the experimental problems posed by supersymmetric theories and to analyze the capabilities of an SSC to find the many new particles predicted by these theories. The plan of this report is as follows. The present theoretical situation of supersymmetric phenomenology is discussed, and the results contained in the literature are briefly reviewed. The experimental signatures for the production of various SUSY particles are examined with varying assumptions about the SUSY masses and decay scenarios. The background from known physics to events containing the new SUSY particles is discussed. We pay particular attention to the two jet background. A discussion of the characteristics of events containing SUSY particles is given, including the E/sub t/ missing spectra and the average number of jets per event. Trigger requirements necessary to identify SUSY particles are considered. The results of two detector simulations are presented: one is a classical 4..pi.. detector for which we have used the CDF simulation package and the other is a simple 4..pi.. calorimeter. Finally, a Monte Carlo written by R.M. Barnett and H. Haber is discussed, and their results are compared with those obtained from ISAJET. 14 references, 30 figures.
Date: October 1, 1984
Creator: Dawson, S.; Savoy-Navarro, A.; Alverson, G.; Barnett, R.M.; Fernandez, E.; Freeman, J. et al.
Partner: UNT Libraries Government Documents Department

Search for neutrino oscillations at the Brookhaven AGS

Description: We report on a search for neutrino oscillations of the type nu/sub ..mu../ ..-->.. nu/sub e/ in a detector located an effective distance of 96m from the neutrino source in the wide band neutrino beam at the Brookhaven AGS. No excess of electron events was observed. The resulting upper limit on the strength of the mixing between nu/sub ..mu../ and nu/sub e/ in the case of large mass difference ..delta..m/sup 2/ = absolute value m/sub 1//sup 2/ - m/sub 2//sup 2/ between the neutrino mass eigenstates m/sub 1/ and m/sub 2/ is sin/sup 2/2..cap alpha.. less than or equal to 3.4 x 10/sup -3/ at 90% CL. The corresponding upper limit for small mass difference is ..delta..m/sup 2/sin2..cap alpha.. < 0.43 eV/sup 2/. 9 refs.
Date: February 20, 1985
Creator: Ahrens, L.A.; Aronson, S.H.; Connolly, P.L.; Gibbard, B.G.; Murtagh, M.J.; Murtagh, S.J. et al.
Partner: UNT Libraries Government Documents Department

Gluonia. [Xi-2200 resonances]

Description: The postulated existence of hadrons with no quark content, implied by the non-Abelian nature of quantum chromodynamics, has been the object of much experimental activity. Recent data from radiative psi decay permit a confrontation of available evidence with the most simple-minded criteria for their appearance. In the absence of compellingly positive evidence we give a rating of the relative merits of several possible candidates. 36 references, 17 figures.
Date: January 1, 1985
Creator: Heusch, C.A.
Partner: UNT Libraries Government Documents Department

D0 Project at Fermilab

Description: The D0 Project will explore 2 TeV anti pp collisions at Fermilab using a highly optimized calorimetric detector, to elucidate the new physics coming out of the SppS, and to explore the new higher energy regime. The design and physics potential of the detector system are described.
Date: January 1, 1984
Creator: Marx, M.D.
Partner: UNT Libraries Government Documents Department

Operation of a high-P/sub T/ spectrometer arm at 10/sup 33/ cm/sup -2/ sec/sup -1/ with particle identification

Description: In the Proceedings of the 1978 Isabelle Summer Study a high-pT spectrometer pair is presented as a prototype high-luminosity experiment. We consider here an updated version of this apparatus with the following questions in mind: (1) what rate capabilities are required to cope with L = 10/sup 33/cm/sup -2/sec/sup -1/; (2) what segmentation is needed to deal with the particle densities expected in high pT jets; and (3) is the resulting device within the reach of present technology. The current version of the device and the expected rates are presented, and the rates and segmentation of the components are discussed. The results of calculations related to event pile-up and triggering are presented. The main conclusion, that particle identification appears to be quite feasible at these rates, is discussed in detail. (WHK)
Date: January 1, 1983
Creator: Aronson, S.; Goldberg, M.; Holder, M. & Loh, E.
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

The SLD (SLC Large Detector) calorimeter systems

Description: A brief description is given of the SLD calorimeter system, with emphasis on the iron calorimeter/muon identifier. Design choices and expected performance are summarized. 6 refs., 8 figs.
Date: July 1, 1989
Creator: Benvenuti, A.C.; Piemontese, L.; Calcaterra, A.; De Sangro, R.; De Simone, P.; Peruzzi, I. et al.
Partner: UNT Libraries Government Documents Department

Report of the large solenoid detector group

Description: This report presents a conceptual design of a large solenoid for studying physics at the SSC. The parameters and nature of the detector have been chosen based on present estimates of what is required to allow the study of heavy quarks, supersymmetry, heavy Higgs particles, WW scattering at large invariant masses, new W and Z bosons, and very large momentum transfer parton-parton scattering. Simply stated, the goal is to obtain optimum detection and identification of electrons, muons, neutrinos, jets, W's and Z's over a large rapidity region. The primary region of interest extends over +-3 units of rapidity, although the calorimetry must extend to +-5.5 units if optimal missing energy resolution is to be obtained. A magnetic field was incorporated because of the importance of identifying the signs of the charges for both electrons and muons and because of the added possibility of identifying tau leptons and secondary vertices. In addition, the existence of a magnetic field may prove useful for studying new physics processes about which we currently have no knowledge. Since hermeticity of the calorimetry is extremely important, the entire central and endcap calorimeters were located inside the solenoid. This does not at the moment seem to produce significant problems (although many issues remain to be resolved) and in fact leads to a very effective muon detector in the central region.
Date: September 1, 1987
Creator: Hanson, G. G.; Mori, S.; Pondrom, L. G.; Williams, H. H.; Barnett, B.; Barnes, V. et al.
Partner: UNT Libraries Government Documents Department

Cerenkov ring imaging detector development for SLD

Description: Progress in the development of a time projection style photoelectron detector is reported. The development is intended to demonstrate the principles and determine specifications for a practical design of the large CRID device recently described in the SLD design report, wherein a large detector for the Stanford Linear Collider is described. The drift detector utilizes the technique of photo-ionization of Cerenkov light in tetrakis-dimethyl-amino-ethylene (TMAE) vapor at (1700 to 2200 A), and drifting the photoelectrons ten's of centimeters to a proportional chamber picket fence, where the drift time provides one coordinate and the wire number the other coordinate. Results are reported on the drifting of photoelectrons from the Cerenkov light and a light pulser over distances of 10 to 60 centimeters.
Date: November 1, 1984
Creator: Williams, S.; Ashford, V.; Bird, F.; Leith, D.W.G.S.; Shimomura, T.; Shapiro, S. 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

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

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

Forward spectrometers at the SSC

Description: Most of SSC phase space and a great deal of physics potential is in the forward/backward region (absolute value of theta < 100 mrad). Comprehensive open-geometry spectrometers are feasible and very cost effective. Examples of such devices are sketched. Because such spectrometers are very long and may operate at high ..beta.. and longer bunch spacing, they impact now on SSC interaction - region design. The data acquisition load is as heavy as for central detectors, although there may be less emphasis on speed and more emphasis on sophisticated parallel and/or distributed processing for event selection, as well as on high-capacity buffering.
Date: January 1, 1986
Creator: Bjorken, J.D.
Partner: UNT Libraries Government Documents Department

A high rate transition radiation detector for particle identification in a hadron beam

Description: A Transition Radiation Detector (TRD) was built for the purpose of tagging beam particles in a high rate (/approximately/2 MHz) 250 GeV/c hadron beam during data taking for Experiment 769 at Fermilab. The availability of a good ''tool kit'', including a Monte Carlo program which could reliably predict the detector performance, made it possible to design and build the TRD in approximately one year. Pion or proton samples, each with a small contamination due to the other, could be selected with high efficiency by making cuts on the number of planes of the TRD registering hits for each incident beam particle. The detector is expected to work well to separate kaons from pions in the 500 GeV/c negative beam for E791. 15 refs., 8 figs., 1 tab.
Date: August 1, 1989
Creator: Errede, D.; Sheaff, M.; Fenker, H. & Mantsch, P.
Partner: UNT Libraries Government Documents Department

The physics program of a high-luminosity asymmetric B Factory at SLAC

Description: A high-luminosity asymmetric energy B Factory, proposed as an upgrade to the PEP storage ring at SLAC, provides the best opportunity to study CP violation as a means of testing the consistency of the Standard Model. If the phenomenon of CP violation is explained by the Standard Model simply through the non-zero angles and phase of the Kobayashi-Maskawa matrix, then there are precise relations between the K-M parameters and the various measurable CP-violating asymmetries in B meson decay. Should these consistency relations fail, the origin of CP violation must lie outside the Standard Model framework. Our measurements would then lead to the first experiment-driven extensions of the Standard Model. The B Factory will also carry out a varied, high-quality program of studies of other aspects of the physics of b quarks, as well as high-precision measurements in {tau} and charm physics. We describe a detailed series of measurements to be carried out in the first few years at a peak luminosity of 3 {times} 10{sup 33} cm{sup -2}sec{sup -1}, the initial luminosity goal of the B Factory, as well as the program accessible to a larger data sample.
Date: October 1, 1989
Partner: UNT Libraries Government Documents Department

The LASS (Larger Aperture Superconducting Solenoid) spectrometer

Description: LASS is the acronym for the Large Aperture Superconducting Solenoid spectrometer which is located in an rf-separated hadron beam at the Stanford Linear Accelerator Center. This spectrometer was constructed in order to perform high statistics studies of multiparticle final states produced in hadron reactions. Such reactions are frequently characterized by events having complicated topologies and/or relatively high particle multiplicity. Their detailed study requires a spectrometer which can provide good resolution in momentum and position over almost the entire solid angle subtended by the production point. In addition, good final state particle identification must be available so that separation of the many kinematically-overlapping final states can be achieved. Precise analyses of the individual reaction channels require high statistics, so that the spectrometer must be capable of high data-taking rates in order that such samples can be acquired in a reasonable running time. Finally, the spectrometer must be complemented by a sophisticated off-line analysis package which efficiently finds tracks, recognizes and fits event topologies and correctly associates the available particle identification information. This, together with complicated programs which perform specific analysis tasks such as partial wave analysis, requires a great deal of software effort allied to a very large computing capacity. This paper describes the construction and performance of the LASS spectrometer, which is an attempt to realize the features just discussed. The configuration of the spectrometer corresponds to the data-taking on K and K interactions in hydrogen at 11 GeV/c which took place in 1981 and 1982. This constitutes a major upgrade of the configuration used to acquire lower statistics data on 11 GeV/c K p interactions during 1977 and 1978, which is also described briefly.
Date: April 1, 1986
Creator: Aston, D.; Awaji, N.; Barnett, B.; Bienz, T.; Bierce, R.; Bird, F. et al.
Partner: UNT Libraries Government Documents Department