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Excitation of simple atoms by slow magnetic monopoles

Description: We present a theory of excitation of simple atoms by slow moving massive monopoles. Previously presented results for a monopole of Dirac strength on hydrogen and helium are reviewed. The hydrogen theory is extended to include arbitrary integral multiples of the Dirac pole strength. The excitation of helium by double strength poles and by dyons is also discussed. It is concluded that a helium proportional counter is a reliable and effective detector for monopoles of arbitrary strength, and for negatively charged dyons.
Date: January 1, 1984
Creator: Kroll, N.M.; Parke, S.J.; Ganapathi, V. & Drell, S.D.
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

Charged Particle Tracking and Vertex Detection Group summary report

Description: Charged particle tracking is essential in order to investigate the new physics expected at the SSC. The Tracking Group studied radiation damage and rate limitations to tracking devices, vertex detectors, and central tracking. The Group concluded that silicon strips and large wire tracking chambers with small cells can probably survive at the design luminosity of 10/sup 33/ cm/sup -2/ sec/sup -1/; however, the presently designed electronics for silicon strip vertex detectors can withstand a luminosity of only 10/sup 31/ cm/sup -2/ sec/sup -1/. Wire chambers at a radius of less than about 25 cm can withstand a luminosity of less than or equal to 10/sup 32/ cm/sup -2/ sec/sup -1/ only. Actual tracking and pattern recognition in central tracking chambers at a luminosity of 10/sup 33/ cm/sup -2/ sec/sup -1/ will be very difficult because of multiple interactions within the resolving time of the chambers; detailed simulations are needed in order to decide whether tracking is indeed possible at this luminosity. Scintillating glass fibers are an interesting possibility both for vertex detectors and for central trackers, but much research and development is still needed both on the fibers themselves and on the readout.
Date: September 1, 1984
Creator: Hanson, G. & Meyer, D.
Partner: UNT Libraries Government Documents Department

Lifetime measurements for bottom hadrons

Description: The review of lifetime measurements of bottom hadrons begins with a first measurement by JADE, followed by similar measurements by MAC and MKII groups. New MAC data are reviewed based on a total of 75,000 multihadron events taken at a c.m. energy of 29 GeV. According to Monte Carlo calculations, 18% of the lepton candidates stem from charm decay and roughly 30% were misidentified hadrons. DELCO studied electrons obtained from 42,000 multihadron events at 29 GeV. The electrons were identified by means of Cerenkov counters. JADE analayzed 22,000 multihadron events at 35 GeV. Data were analyzed using two methods - one using a sample of b-enriched events, and the other using weighted distributions. The TASSO results were obtained with two different configurations of the detector - one of which used a drift chamber and the other a vertex detector. (LEW)
Date: September 1, 1984
Creator: Wolf, G.
Partner: UNT Libraries Government Documents Department

Searching for quark and lepton compositeness at the SSC

Description: We examine a variety of issues connected with searching for compositeness at the SSC. These include effects of resolution, alternative methods of looking for deviations from QCD predictions, advantages of polarized beams, and effects of compositeness on photon detection. We also consider how physics may look if the compositeness scale is as low as a few TeV. 17 refs.
Date: January 1, 1984
Creator: Albright, C. H.; Bars, I.; Blumenfeld, B.; Braune, K.; Dine, M.; Ferbel, T. et al.
Partner: UNT Libraries Government Documents Department

Signals of new W's and Z's

Description: If new heavy charged and/or neutral gauge bosons exist with masses below 5 to 10 TeV, they can be observed at the SSC. In this report, we summarize the work of the New W/Z Physics Subgroup. The expected properties of new heavy gauge bosons (such as new W's and Z's or horizontal gauge bosons) are summarized. We then discuss various signatures of these new gauge bosons and their implications for detector designers. Suggestions for future work are indicated. 60 references.
Date: September 1, 1984
Creator: Haber, H.E.
Partner: UNT Libraries Government Documents Department

Axions in astrophysics and cosmology

Description: Axion models often have a spontaneously broken exact discrete symmetry. In that case, they have discretely degenerate vacua and hence domain walls. The properties of the domain walls, the cosmological catastrophe they produce and the ways in which this catastrophe may be avoided are explained. Cosmology and astrophysics provide arguments that imply the axion decay constant should lie in the range 10/sup 8/ GeV less than or equal to f/sub a/ less than or equal to 10/sup 12/ GeV. Reasons are given why axions are an excellent candidate to constitute the dark matter of galactic halos. Using the coupling of the axions to the electromagnetic field, detectors are described to look for axions floating about in the halo of our galaxy and for axions emitted by the sun. (LEW)
Date: July 1, 1984
Creator: Sikivie, P.
Partner: UNT Libraries Government Documents Department

First- and second-order charged particle optics

Description: Since the invention of the alternating gradient principle there has been a rapid evolution of the mathematics and physics techniques applicable to charged particle optics. In this publication we derive a differential equation and a matrix algebra formalism valid to second-order to present the basic principles governing the design of charged particle beam transport systems. A notation first introduced by John Streib is used to convey the essential principles dictating the design of such beam transport systems. For example the momentum dispersion, the momentum resolution, and all second-order aberrations are expressed as simple integrals of the first-order trajectories (matrix elements) and of the magnetic field parameters (multipole components) characterizing the system. 16 references, 30 figures.
Date: July 1, 1984
Creator: Brown, K.L. & Servranckx, R.V.
Partner: UNT Libraries Government Documents Department

Microstore: the Stanford analog memory unit

Description: An NMOS device has been developed which provides high speed analog signal storage and readout for time expansion of transient signals. This device takes advantage of HMOS-1 VLSI technology to implement an array of 256 storage cells. Sequential samples of an input waveform can be taken every 5 ns while providing an effective sampling aperture time of less than 1 ns. The design signal-to-noise ratio is 1 part in 2000. Digital control circuitry is provided on the chip for controlling the read-in and read-out processes. A reference circuit is incorporated in the chip for first order compensation of leakage drifts, sampling pedestals, and temperature effects.
Date: November 1, 1984
Creator: Walker, J.T.; Chae, S.I.; Shapiro, S. & Larsen, R.S.
Partner: UNT Libraries Government Documents Department

Wake fields and wake field acceleration

Description: In this lecture we introduce the concepts of wake fields and wake potentials, examine some basic properties of these functions, show how they can be calculated, and look briefly at a few important applications. One such application is wake field acceleration. The wake field accelerator is capable of producing the high gradients required for future very high energy e/sup +/e/sup -/ linear colliders. The principles of wake field acceleration, and a brief description of experiments in progress in this area, are presented in the concluding section. 40 references, 27 figures.
Date: December 1, 1984
Creator: Bane, K.L.F.; Wilson, P.B. & Weiland, T.
Partner: UNT Libraries Government Documents Department

Heavy ion fusion accelerator research in the US

Description: Three new development have taken place in the HIFAR program. First, a decision has been made to concentrate the experimental program on the development of multiple-beam induction linacs. Second, new beam transport experiments over a large number of quadrupole elements show that stable beam propagation occurs for significantly higher beam currents than had been believed possible a few years ago. Third, design calculations now show that a test accelerator of modest size and cost can come within a factor of three of testing almost all of the physics and technical issues appropriate to a power-plant driver.
Date: September 1, 1984
Creator: Bangerter, R.O.; Godlove, T.F.; Herrmannsfeldt, W.B. & Keefe, D.
Partner: UNT Libraries Government Documents Department

Constructing a bit string universe. Progress report

Description: We present a case for discrete, constructive physics that generates four scale constants, a connection to laboratory events and scattering theory that ties these to the dimensional constants c, h, m/sub p/, and G, and a tentative quantum number assignment consistent with standard model for leptons and quarks with three generations. Current first approximations from the theory are dirac constant c/e/sup 2/ = 137 +- O(1/137), dirac constant c/Gm/sup 2//sub p/ - 2/sup 127/ + 136 approx. = 1.7 x 10/sup 38/(1 +- 0(1/137)), and m/sub p//m/sub e/ = 1836.151497... +-. Our understanding of wave-particle dualism and observational cosmology creates no more experimental paradoxes than currently accepted views - perhaps fewer. 19 references.
Date: February 1, 1984
Creator: Noyes, H.P.; Manthey, M.J. & Gefwert, C.
Partner: UNT Libraries Government Documents Department

Dispersion function and closed orbit distortion in accelerator rings

Description: Dispersion Function Distortion (DFD) affects accelerator operation and thus deserves attention, somehow as Closed Orbit Distortion (COD) does. Consequently, DFD correction schemes under computer control have been successfully developed and adopted in many rings such as PEP. It was realized during the author's study on the problem, however, that the existing DFD correction schemes ignore those terms that arise from bending magnets and their edges. Being of first order of correcting strength, the terms are significant in small rings, though really not important in big machines. This reminds of what has been noticed in the chromaticity calculation. A comparison between this note and the existing schemes shows a difference in DFD sensitivity matrix that is significant for sub-GeV machines and appears not negligible even for SPEAR. Many storage rings at energy around 0.7 to 3 GeV are being proposed, constructed or operated everywhere as synchrotron radiation generators. Vertical DFD correction should be an important part of their operation, because vertical DFD enlarges beam height and hence reduces light source brightness. This is the purpose the author had in mind when beginning to study the problem. In addition, a correct DFD analysis along with COD analysis can hopefully help spot magnet misalignments and remove them.
Date: February 1, 1984
Creator: Liu, R.Z.
Partner: UNT Libraries Government Documents Department

Report of the working group on CP violation and rare decays

Description: It has been pointed out that, with its high energy and luminosity, the SSC may provide the best or only way in which CP violation in heavy meson decays or the rare decay modes of such mesons can be observed. The major problem in the exploitation of the high rates of heavy quark production is the identification of interesting decays in the midst of a large background of more conventional processes. There have been some optimistic reports on the feasibility of such experiments, but relatively little quantitative backup has been provided. In the present report, we concentrate exclusively on B-meson decays. As is the case for K mesons, but not for charm or top decays, the favored modes are suppressed by the smallness of Cabibbo-Kobayashi-Maskawa angles, and therefore rare modes are relatively more frequent and potentially easier to observe.
Date: October 1, 1984
Creator: Cronin, J.W.; Deshpande, N.G.; Kane, G.L.; Luth, V.C.; Odian, A.C.; Machacek, M.E. 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 energy resolution and related properties of an SCG1-C scintillation glass shower counter array for 1 to 25 GeV positrons

Description: We report the measurement of the energy resolution of a 4 x 4 array of SCG1-C scintilation glass counters (Ohara Optical Glass Manufacturing Co., Ltd.) exposed to positrons in the energy range of 1 to 25 GeV. Each element of the array was 20.5 radiation lengths long. The resolution of the array was measured both with and without a 3.5 radiation length SCG1-C scintillation glass active converter and 0.2 radiation length hodoscopes used to measure shower position. We obtained an energy resolution sigma/E = (1.63 + 1/46/ ..sqrt..E)% without the active converter and sigma/E = (0.64/ ..sqrt..E)% with the active converter. Performing a partial correction for the average energy loss in the 0.2 radiation length hodoscopes resulted in an energy resolution of sigma/E = (0.50 + 3.43/ ..sqrt..E)% for the active converter measurement. We also report on the measurement of the absolute number of photons produced by 1 GeV showers, the optical attenuation length for the light produced by showers, the fraction or the total light output that is due to Cerenkov light relative to scintillation light for showers, and the radiation darkening sensitivity of the scintillation glass.
Date: January 1, 1984
Creator: Wagoner, D. E.; Cox, B.; Judd, D. J.; Hale, G.; Mazur, P. O.; Murphy, C. T. et al.
Partner: UNT Libraries Government Documents Department

Measurement of electromagnetic shower position and size with a saturated avalanche tube hodoscope and a fine grained scintillation hodoscope

Description: A hodoscope has been constructed from 100 ..mu.. m diameter wires and brass tubes (1.2 x 0.7 cm/sup 2/ cross section) filled with a mixture of argon, ethane and ethyl alcohol. It has been tested in the saturated avalanche mode in an SCG1-C electromagnetic shower detector to determine its properties for the measurement of the position and size of electromagnetic showers. Two of these tube hodoscopes were positioned 3.5 radiation lengths deep in the detector and the profiles of 1 to 25 GeV electromagnetic showers were measured. Simultaneous measurements were performed using a plane of twenty, 0.5 cm wide scintillation counters positioned immediately behind the gas tube hodoscope. In addition the transition between saturated avalanche and limited streamer modes has been measured for the tube hodoscopes.
Date: January 1, 1984
Creator: Rameika, R.; Cox, B.; Jenkins, C.M.; Judd, D.J.; Hale, G.; Mazur, P.O. 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

Some numbers on the SLAC klystron windows

Description: The attenuation in our standard copper rectangular wave guides at 10 cm wave length is known to be 0.7 db/100 ft. If the wave guide were made of 70/30 Cupro-nickel, the same alloy the window sleeve is made of, the attenuation constant would go up by the inverse square root of the ratio of the conductivities (skin effect formula). Thus the attenuation constant would be ..beta.. = 12.8 10/sup -3/ m/sup -1/. The length of the sleeve L = 23 mm. Hence a piece of rectangular wave guide of equal length would, at 50 kW incident average power, sustain resistive losses = 2 P ..beta.. L = 29.54 Watt.
Date: March 1, 1984
Creator: Krienen, F.
Partner: UNT Libraries Government Documents Department

Search for charmed F mesons in e/sup +/e/sup -/ collisions with the crystal ball

Description: In this work an experimental search for the production of the charmed F and F* mesons in e/sup +/e/sup -/ collisions is presented. The data for this analysis were obtained over a center of mass energy region from 3.86 GeV to 4.5 GeV with the Crystal Ball detector at SPEAR. The inclusive eta production cross section has been measured as a function of the center of mass energy. It was found to be almost constant with no indication for an significant increase which was cited as evidence for F production by a previous experiment. A search for F anti F, F* anti F and F* anti F* production with the decay F/sup + -/ ..-->.. eta..pi../sup + -/ has also been made, but no signal was observed. Upper limits for sigma/sub F(*) anti F(*)/ BR(F/sup + -/ ..-->.. eta..pi../sup + -/) are given for various F and F* masses. The measurements presented here are inconsistent with results from earlier experiments which had been used to establish the existence of the F mesons. The inclusive ..gamma.. spectrum at E/sub cm/ = 4.33 GeV has also been used to obtain upper limits on F* production. These results disagree with theoretical expectations for the F* anti F* production cross section for the F and F* masses quoted by other experiments. In connection with this analysis the cross section for D* production was also measured at E/sub cm/ = 4.33 GeV and was found to be 7.4nb +- 1.3nb.
Date: January 1, 1984
Creator: Horisberger, R.P.
Partner: UNT Libraries Government Documents Department

Environmental influences contributing to window failure of the SLAC 50 MW klystron

Description: The additional heating of the klystron window is due to the intense x-ray level, produced inside the klystron, illuminating the entrance of the output wave guide. Photo-electric effect, although of low efficiency, produces enough electrons at the right location and right phase to start multipactor, which progresses with increasing intensity towards the window. The intercepted charge and the concomitant x-radiation heat the window, but the heating is not the cause of the breakdown per se. The accumulated charge on the window creates electric stress, which comes in addition to the RF stress. It could therefore be a major cause of electrical breakdown. The coating, which is intended to carry this charge off, should have a relaxation time constant small compared to the pulse duration. Unfortunately the coating can not be made conducting enough because it conflicts with the Joule heating in the RF field.
Date: March 1, 1984
Creator: Krienen, F.
Partner: UNT Libraries Government Documents Department

Particel substructure. A common theme of discovery in this century

Description: Some example of modern developments in particel physics are given which demonstrate that the fundamental rules of quantum mechanics, applied to all forces in nature as they became understood, have retained their validity. The well-established laws of electricity and magnetism, reformulated in terms of quantum mechanics, have exhibited a truly remarkable numerical agreement between theory and experiment over an enormous range of observation. As experimental techniques have grown from the top of a laboratory bench to the large accelerators of today, the basic components of experimentation have changed vastly in scale but only little in basic function. More important, the motivation of those engaged in this type of experimentation has hardly changed at all.
Date: February 1, 1984
Creator: Panofsky, W.K.H.
Partner: UNT Libraries Government Documents Department

Analytic solution for the problem of gridded gap-electron flow interaction

Description: The present study is motivated by the modelling of high-power klystrons. The two basic components of a Klystron are the resonant cavities and the drift spaces. This paper addresses only the first of these two components. Modelling of the drift spaces is deferred to future work. The formulation is not restricted to Klystron modelling, but is applicable to any problem involving the interaction of an electron beam with a resonant cavity. While the theory of Klystrons has been worked out in detail in the small signal limit, the problem remains largely unsolved when the signals are large. In particular, the hydrodynamic models of electron beams used to derive the small signal theories fail when particle trajectories cross each other. In this paper, we employ a Vlasov description of the electron beam to study the Klystron problem. In the Vlasov formulation we follow the evolution of the electron distribution function in phase-space. The general framework can naturally accommodate particle crossing, and the beam dynamics is accurately described even when the signals are large.
Date: January 1, 1984
Creator: Kheifets, S.; Yu, S. & Jaeger, J.
Partner: UNT Libraries Government Documents Department

Annual environmental monitoring report, January-December 1983

Description: Environmental monitoring results continue to demonstrate that environmental radiological impact due to SLAC operation is not easily distinguishable from natural environmental sources. During 1983, the maximum approximated neutron dose near the site boundary was 5 mrem. There have been no measurable increases in radioactivity in ground water attributable to SLAC operations since operation began in 1966. We have never found any evidence of radioactivity in ground water in excess of natural background radioactivity from uranium and thorium decay chains and potassium-40. Airborne radioactivity released from SLAC continues to make only a negligible environmental impact, and results in a site-boundary annual dose of less than 0.3 mrem; this represents less than 0.3% of the annual dose from the natural radiation environment, and about 0.06% of the technical standard. 8 references, 5 figures, 4 tables.
Date: March 1, 1984
Partner: UNT Libraries Government Documents Department