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Review of recent progress in the development of Cerenkov Ring Imaging Detectors

Description: The principle behind the Cherenkov Ring Imaging Detectors (CRIDs) involves focussing the Cherenkov light, emitted by a relativistic charged particle in passing through a radiator medium, onto a high efficiency photocathode which can be in turn read out with good spatial resolution, to localize the point of origin of the photoelectrons. This information permits the reconstruction of the circle of Cherenkov light for each particle above threshold, and hence the determination of the Cherenkov angle to an accuracy of a few percent. The groups currently working on these detectors are discussed, the status of these projects is examined, and progress is reported on the R and D on two 4-pi devices being prepared for physics at the Z. The activities are being done at Fermilab, CERN, and SLAC. 8 refs., 32 figs. (LEW)
Date: November 1, 1985
Creator: Leith, D.W.G.S.
Partner: UNT Libraries Government Documents Department

Direct electron pair production in. pi. /sup -/p interactions at 16 GeV/c and a model for direct lepton and photon production at low P/sub T/

Description: The production of prompt electron-positron pairs in 16 GeV/c ..pi../sup -/p collisions has been measured using the LASS spectrometer at SLAC. An excess of events is observed above the estimated contributions of direct and Dalitz decay of known resonances in the kinematic range defined by 0.1 less than or equal to x less than or equal to 0.45, 0 less than or equal to P/sub T/ less than or equal to 0.8 GeV/c and 0.2 less than or equal to M(e/sup +/e/sup -/) less than or equal to 0.7 GeV/c/sup 2/. The excess signal decreases slowly with increasing M, but exhibits very steep x and P/sub T//sup 2/ dependence. The contribution of this signal to the e/sup +/e/sup -//..pi../sup +/..pi../sup -/ and ..gamma../..pi.. ratios is discussed. Detailed comparisons are made between e/sup +/e/sup -/ distributions and the corresponding low mass ..mu../sup +/..mu../sup -/ distributions, and a simple production mechanism is proposed which describes the 16 GeV/c data well. The implications for direct photon production are presented, and it is shown that the model provides simultaneously a good description of the experimental data on the (e/..pi..) and (..mu../..pi..) ratios for p/sub T/ < 1 GeV/c.
Date: July 1, 1981
Creator: Blockus, D.; Dunwoodie, W. & Leith, D.W.G.S.
Partner: UNT Libraries Government Documents Department

Use of elementary particle interactions for radiological imaging

Description: The potential for the use of inelastic high energy particle reactions to produce radiological images is parable to that of computerized axial tomography at a fraction of the radiation exposure. In addition, the comparison of coherently produced events to the total inelastic cross section should allow a probe of the chemical composition (i.e., average Z) of the material being studied. The performance of this technique is reviewed and some preliminary results using a 5 GeV/c ..pi../sup -/ beam at SLAC are presented.
Date: January 1, 1979
Creator: Williams, S.H. & Leith, D.W.G.S.
Partner: UNT Libraries Government Documents Department

Preliminary results on tests of a Cerenkov ring imaging device employing a photoionizing PWC

Description: A brief description of techniques and problems of ring imaging Cerenkov detectors employing photoionizing PWC's is discussed. Preliminary results on a one dimensional ring imaging device tested at SLAC in May and June of 1978 are then presented. These results include rough measurements of the Cerenkov ring in nitrogen, argon, neon, and helium produced by a collimated positron beam.
Date: August 1, 1978
Creator: Durkin, S.; Honma, A. & Leith, D.W.G.S.
Partner: UNT Libraries Government Documents Department

Cerenkov counters at ISABELLE. [71 references]

Description: The Cherenkov counter described for use at Isabelle is a threshold counter in which light is focussed on phototubes. The counter is applicable in large-angle, small-aperture magnetic spectrometers for measurement of particle yields at large p/sub T/. Three of these counters will provide complete ..pi..-K-p separation in the range of 7-20 GeV/c. Other Cherenkov counters are discussed and a bibliography of relevant literature on the counters utilizing photoionization is included. (FS)
Date: January 1, 1977
Creator: Etkin, A.; Kostoulas, I.; Leith, D.W.G.S. & Thun, R.
Partner: UNT Libraries Government Documents Department

High gain multigap avalanche detectors for Cerenkov ring imaging

Description: We report on a continuing study of multigap parallel plate avalanche chambers, primarily as photoelectron detectors for use with Cerenkov ring imaging counters. By suitable control of the fields in successive gaps and by introducing screens to reduce photon feedback to the cathode the gain many be increased considerably. We have obtained gains in excess of 6 x 10/sup 7/ for photoelectrons with a good pulse height spectrum and expect to increase this further. We discuss the use of resistive anodes to give avalanche positions in two dimensions by charge division.
Date: October 1, 1980
Creator: Gilmore, R.S.; Lavender, W.M.; Leith, D.W.G.S. & Williams, S.H.
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

A High-resolution TOF Detector _ A Possible Way to Compete with a RICH Detector

Description: Using two identical 64-pixel Burle/Photonis MCP-PMTs to provide start and stop signals, they have achieved a timing resolution of {sigma}{sub Single{_}detector} {approx} 7.2 ps for N{sub pe} {approx} 50 photoelectrons (N{sub pe}) with a laser diode providing a 1 mm spot on the MCP window. The limiting resolution achieved was {sigma}{sub Single{_}detector} {approx} 5.0 ps for N{sub pe} {approx} 180, for which they estimate the MCP-PMT contribution of {sigma}{sub MCP-PMT} {approx} 4.5 ps. The electronics contribution is estimated as {sigma}{sub Electrons} = 3.42 ps. These results suggest that an ultra-high resolution TOF detector may become a reality at future experiments one day.
Date: July 25, 2008
Creator: Va'vra, J; /SLAC; Ertley, C.; /Argonne; Leith, D.W.G.S.; Ratcliff, B. et al.
Partner: UNT Libraries Government Documents Department

A 30 ps Timing Resolution for Single Photons with Multi-pixel Burle MCP-PMT

Description: We have achieved {approx}30 psec single-photoelectron and {approx}12ps for multi-photoelectron timing resolution with a new 64 pixel Burle MCP-PMT with 10 micron microchannel holes. We have also demonstrated that this detector works in a magnetic field of 15kG, and achieved a single-photoelectron timing resolution of better than 60 psec. The study is relevant for a new focusing DIRC RICH detector for particle identification at future Colliders such as the super B-factory or ILC, and for future TOF techniques. This study shows that a highly pixilated MCP-PMT can deliver excellent timing resolution.
Date: July 5, 2006
Creator: Va'vra, J.; Benitez, J.; Coleman, J.; Leith, D.W.G.S.; Mazaheri, G.; Ratcliff, B. et al.
Partner: UNT Libraries Government Documents Department

Development of a Focusing DIRC

Description: Benefiting from the recent introduction of new fast vacuum-based photon detectors with a transit time spread of {sigma}{sub TTS} {approx} 30-150 ps, we are developing a novel RICH detector capable of correcting the chromatic error through good time measurements; we believe that this is the first time such a technique has been demonstrated. We have built and successfully tested a particle identification detector called ''Focusing DIRC''. The concept of the prototype is based on the BaBar DIRC, with several important improvements: (a) much faster pixelated photon detectors based on Burle MCP-PMTs and Hamamatsu MaPMTs, (b) a focusing mirror which allows the photon detector to be smaller and less sensitive to background in future applications, (c) electronics allowing the measurement of single photon timing to better than {sigma} {approx} 100-200ps, which allows a correction of the chromatic error. The detector was tested in a SLAC 10GeV/c electron test beam. This detector concept could be used for particle identification at Super B-factory, ILC, GlueX, Panda, etc.
Date: December 12, 2006
Creator: Benitez, J.; Bedajanek, I.; Leith, D.W.G.S.; Mazaheri, G.; Ratcliff, B.; Suzuki, K. et al.
Partner: UNT Libraries Government Documents Department

Status of the Fast Focusing DIRC (fDIRC)

Description: We have built and successfully tested a novel particle identification detector concept, the Fast Focusing DIRC (fDIRC). The prototype's concept is based on the BaBar DIRC with several important improvements: (a) much faster pixelated photon detectors based on Burle MCP-PMTs and Hamamatsu MaPMTs, (b) a focusing mirror allowing a smaller photon detector, reducing the sensitivity to backgrounds in future applications, (c) electronics capable of measuring the single photon resolution to better than {sigma} {approx} 100-200ps. The fDIRC is the first RICH detector to successfully correct the chromatic error by timing.
Date: February 4, 2008
Creator: Benitez, J.; Leith, D.W.G.S.; Mazaheri, G.; Ratcliff, B.N.; Schwiening, J.; Vavra, J. et al.
Partner: UNT Libraries Government Documents Department

Beam Test of a Time-of-Flight Detector Prototype

Description: We report on results of a Time-of-Flight, TOF, counter prototype in beam tests at SLAC and Fermilab. Using two identical 64-pixel Photonis Microchannel Plate Photomultipliers, MCP-PMTs, to provide start and stop signals, each having a 1 cm-long quartz Cherenkov radiator, we have achieved a timing resolution of {sigma}{sub Single{_}detector} {approx} 14 ps.
Date: April 1, 2009
Creator: Va'vra, J.; Leith, D.W.G.S.; Ratcliff, B.; /SLAC; Ramberg, E.; Albrow, M. et al.
Partner: UNT Libraries Government Documents Department

A Detailed Study of FDIRC Prototype with Waveform Digitizing Electronics in Cosmic Ray Telescope Using 3D Tracks

Description: We present a detailed study of a novel Cherenkov imaging detector called the Focusing DIRC (FDIRC) with waveform digitizing electronics. In this test study, the FDIRC prototype has been instrumented with seven Hamamatsu H-8500 MaPMTs. Waveforms from {approx}450 pixels are digitized with waveform sampling electronics based on the BLAB2 ASIC, operating at a sampling speed of {approx}2.5 GSa/s. The FDIRC prototype was tested in a large cosmic ray telescope (CRT) providing 3D muon tracks with {approx}1.5 mrad angular resolution and muon energy of E{sub muon} &gt; 1.6 GeV. In this study we provide a detailed analysis of the tails in the Cherenkov angle distribution as a function of various variables, compare experimental results with simulation, and identify the major contributions to the tails. We demonstrate that to see the full impact of these tails on the Cherenkov angle resolution, it is crucial to use 3D tracks, and have a full understanding of the role of ambiguities. These issues could not be fully explored in previous FDIRC studies where the beam was perpendicular to the quartz radiator bars. This work is relevant for the final FDIRC prototype of the PID detector at SuperB, which will be tested this year in the CRT setup.
Date: July 30, 2012
Creator: Nishimura, K.; Dey, B.; /Hawaii U. /UC, Riverside; Aston, D.; Leith, D.W.G.S.; Ratcliff, B. et al.
Partner: UNT Libraries Government Documents Department

SuperB: a Linear High-Luminosity B Factory

Description: This paper is based on the outcome of the activity that has taken place during the recent workshop on ''SuperB in Italy'' held in Frascati on November 11-12, 2005. The workshop was opened by a theoretical introduction of Marco Ciuchini and was structured in two working groups. One focused on the machine and the other on the detector and experimental issues.. The present status on CP is mainly based on the results achieved by BABAR and Belle. Establishment of the indirect CP violation in B sector in 2001 and of the direct CP violation in 2004 thanks to the success of PEP-II and KEKB e{sup +}e{sup -} asymmetric B Factories operating at the center of mass energy corresponding to the mass of the {Upsilon}(4S ). With the two B Factories taking data, the Unitarity Triangle is now beginning to be over constrained by improving the measurements of the sides and now also of the angles {alpha}, and {gamma}. We are also in presence of the very intriguing results about the measurements of sin2{beta} in the time dependent analysis of decay channels via penguin loops, where b {yields} s{bar s}s and b {yields} s{bar d}d. {tau} physics, in particular LFV search, as well as charm and ISR physics are important parts of the scientific program of a SuperB Factory. The physics case together with possible scenarios for the high luminosity SuperB Factory based on the concepts of the Linear Collider and the related experimental issues are discussed.
Date: February 8, 2006
Creator: Albert, J.; Bettarini, S.; Biagini, M.; Bonneaud, G.; Cai, Y.; Calderini, G. et al.
Partner: UNT Libraries Government Documents Department

Progress and commissioning of the SLD Cherenkov Ring Imaging Detector

Description: We report the recent progress of the SLD Cherenkov Ring Imaging Detector. All of the individual components of the device (TPC's, mirrors, liquid radiator trays) have been completed and installed. Almost half of the electronics packages are installed and operational, and the data acquisition system has been commissioned. The liquid C{sub 6}F{sub 14} recirculation system is functioning. The drift gas supply systems are operating well with TMAE, and the gaseous Freon C{sub 5}F{sub 12} recirculator is being brought on-line. Our monitor and control systems are fully functional. The commissioning of all 40 TPCs at full operating voltage has gone very smoothly. The system shows a remarkable immunity to the SLC backgrounds, and yields very clean events, while operating with a single electron sensitivity.
Date: November 1, 1991
Creator: Abe, K.; Hasegawa, K.; Suekane, F.; Yuta, H.; Antilogus, P.; Aston, D. et al.
Partner: UNT Libraries Government Documents Department

Update on K* studies at SLAC (Stanford Linear Accelerator Center)

Description: Results from the systematic study of K spectroscopy, by the LASS group, are reviewed. New data from the study of the reaction K{sup {minus}}p {yields} {bar K}{sup 0}{pi}{sup {minus}}p are presented, and compared to our previous results. Confirmation of three new K* excited states is presented. 6 refs., 13 figs., 5 tabs.
Date: December 1, 1989
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

Strangeonium production from LASS

Description: Results from recent studies of strangeonium mesons produced in the LASS spectrometer by an 11 GeV/c K{sup {minus}} beam are presented. Data fro new analyses of K*{bar K}*, {phi}{phi}, and {eta}{pi}{pi} final states are described. Comparisons are made with results from other hadroproduction, radiative J/{Psi} decay, and {gamma}{gamma} experiments. 24 refs., 5 figs., 2 tabs.
Date: November 1, 1990
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

Electrostatic design of the barrel CRID (Cherenkov Ring Imaging Detector) and associated measurements

Description: We report on the electrostatic design and related measurements of the barrel Cherenkov Ring Imaging Detector for the Stanford Large Detector experiment at the Stanford Linear Accelerator Center Linear Collider. We include test results of photon feedback in TMAE-laden gas, distortion measurements in the drift boxes and corona measurements. 13 refs., 21 figs.
Date: April 1, 1990
Creator: Abe, K.; Hasegawa, K.; Suekane, F.; Yuta, H. (Tohoku Univ., Sendai (Japan). Dept. of Physics); Antilogus, P.; Aston, D. et al.
Partner: UNT Libraries Government Documents Department

Strangeonia and kin; new results from kaon hadroproduction with LASS

Description: Recent results from a high statistics study of strangeonium mesons produced in LASS by an 11 GeV/c K{sup -} beam are reviewed and compared with the quark model. New data from a variety of final states (K*{ovr K*}, {phi}{phi}, {phi}{pi}{sup 0}) produced by hypercharge exchange are described, and compared with results from other hadroproduction modes and from J/{psi} decay. 17 refs., 12 figs.
Date: December 1, 1989
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

J sup P = 1 sup minus radial excitations from LASS data

Description: The experimental status of the strange 1 {sup {minus}} mesons is briefly reviewed and compared with the non-strange sector and quark model expectations. The results described are taken from a 4.1 event/nb exposure of the LASS spectrometer to an 11 GeV/e K{sup {minus}} beam.
Date: December 1, 1991
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

Recent results on K. omega. and. pi. pi. systems from LASS

Description: Preliminary results from ongoing analyses of the K{sup minus}{omega} and the hypercharge exchange produced {pi}{sup minus}{pi}{sup +} systems are presented. The data described are taken from a 4.1 event/nb exposure of the LASS spectrometer to an 11 GeV/cK{sup minus} beam.
Date: December 1, 1991
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department