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Application of GPS in a high precision engineering survey network

Description: A GPS satellite survey was carried out with the Macrometer to support construction at the Stanford Linear Accelerator Center (SLAC). The network consists of 16 stations of which 9 stations were part of the Macrometer network. The horizontal and vertical accuracy of the GPS survey is estimated to be 1 to 2 mm and 2 to 3 mm respectively. The horizontal accuracy of the terrestrial survey, consisting of angles and distances, equals that of the GPS survey only in the ''loop'' portion of the network. All stations are part of a precise level network. The ellipsoidal heights obtained from the GPS survey and the orthometric heights of the level network are used to compute geoid undulations. A geoid profile along the linac was computed by the National Geodetic Survey in 1963. This profile agreed with the observed geoid within the standard deviation of the GPS survey. Angles and distances were adjusted together (TERRA), and all terrestrial observations were combined with the GPS vector observations in a combination adjustment (COMB). A comparison of COMB and TERRA revealed systematic errors in the terrestrial solution. A scale factor of 1.5 ppM +- .8 ppM was estimated. This value is of the same magnitude as the over-all horizontal accuracy of both networks. 10 refs., 3 figs., 5 tabs.
Date: April 1, 1985
Creator: Ruland, R. & Leick, A.
Partner: UNT Libraries Government Documents Department

Effects of slots/holes in disks on frequencies of TM/sub 01/ and EH/sub 11/ waves in the disk-loaded waveguide

Description: The increase in the BBU threshold current is very important for the high and medium energy electron linacs because of a larger operating current attainable or a smaller emittance available at certain operating current. For this purpose, many means can be used, among which the improvement in the accelerating structure itself is always fundamental. SLAC's three-meter long section is unique with truly constant gradient performance. The theoretical analyses and operating experiences at SLAC have indicated that detuning the Nos. 3, 4 and 5 cavities of some sections by 2 or 4 MHz for TM/sub 01/ wave had considerably raised the BBU threshold current. A method of opening four holes symmetrically distributed on disks as described in detail will get the benefits in improvement of BBU threshold current.
Date: March 1, 1985
Creator: Yao, C.G.
Partner: UNT Libraries Government Documents Department

Accelerator physics measurements at the damping ring

Description: Besides the optics measurements described elsewhere, machine experiments were done at the SLC damping ring to determine some of its parameters. The synchrotron radiation energy loss which gives the damping rates was measured by observing the rf-voltage dependence of the synchronous phase angle. The emittance was obtained from the synchrotron light monitor, scraper measurements and by extracting the beam through a doublet and measuring its size for different quadrupole settings. Current dependent effects such as parasitic mode losses, head tail instabilities, synchrotron and betatron frequency shifts were measured to estimate the impedance. Rf-cavity beam loading and its compensation were also studied and ion collection was investigated. All results agree reasonably well with expectations and indicate no limitations to the design performance.
Date: May 1, 1985
Creator: Rivkin, L.; Delahaye, J.P.; Wille, K.; Allen, M.; Bane, K.; Fieguth, T. et al.
Partner: UNT Libraries Government Documents Department

Gluonium candidates from hadronic and e/sup +/e/sup -/ interactions

Description: The experimental approaches exploited in the search for gluonia that are deemed most promising are briefly described, both in hadron-hadron collisions and heavy quarkonium decay. The presently available evidence is summarized for those states that have been claimed as possible gluonia. Proceeding in the order of lowest-mass expectation, categorization is done only in terms of definitive (or putative) J/sup PC/ assignments. 51 refs., 16 figs., 3 tabs. (LEW)
Date: December 1, 1985
Creator: Heusch, C.A.
Partner: UNT Libraries Government Documents Department

Factorization of the Drell-Yan cross section

Description: We state the weak and strong factorization theorems for the Drell-Yan cross section and outline the ingredients involved in their proof. We also discuss the physical picture implied by the factorization results and its phenomenological consequences.
Date: April 1, 1985
Creator: Bodwin, G.T.; Brodsky, S.J. & Lepage, G.P.
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

Isolated data acquisition system for high voltage applications

Description: This report describes the design and operation of a microcomputer controlled system for acquisition of both analog and binary data within the high voltage stages of a linac modulator. The system is comprised of a microprocessor Controller which communicates with the remote data Acquisition circuits via an optical bus. The bus, which uses a 1 MHz Manchester II format, is configured as a loop, starting at the Controller, daisy-chaining the remote cards and terminating back at the Controller. Upon receiving a linac timing pulse, the Controller sends addressed commands to the individual remote cards and receives data back. It then passes this data to the linac control system through a Multibus connection. Each remote circuit can return 16 binary sense and 7 (12 bit) analog parameters within 270 us. This speed is possible because of a pipelined design where one word is transmitted while another is being converted. A data conversion cycle is initiated when a remote data acquisition card receives the proper command and address from the controller.
Date: June 1, 1985
Creator: Waitz, A. & Donaldson, A.
Partner: UNT Libraries Government Documents Department

High energy radiation from neutron stars

Description: Topics covered include young rapidly spinning pulsars; static gaps in outer magnetospheres; dynamic gaps in pulsar outer magnetospheres; pulse structure of energetic radiation sustained by outer gap pair production; outer gap radiation, Crab pulsar; outer gap radiation, the Vela pulsar; radioemission; and high energy radiation during the accretion spin-up of older neutron stars. 26 refs., 10 figs. (GHT)
Date: April 1, 1985
Creator: Ruderman, M.
Partner: UNT Libraries Government Documents Department

Measurement problem in Program Universe. Revision

Description: The ''measurement problem'' of contemporary physics is in our view an artifact of its philosophical and mathematical underpinnings. We describe a new philosophical view of theory formation, rooted in Wittgenstein, and Bishop's and Martin-Loef's constructivity, which obviates such discussions. We present an unfinished, but very encouraging, theory which is compatible with this philosophical framework. The theory is based on the concepts of counting and combinatorics in the framework provided by the combinatorial hierarchy, a unique hierarchy of bit strings which interact by an operation called discrimination. Measurement criteria incorporate c, h-bar and m/sub p/ or (not ''and'') G. The resulting theory is discrete throughout, contains no infinities, and, as far as we have developed it, is in agreement with quantum mechanical and cosmological fact. 15 refs.
Date: July 1, 1985
Creator: Noyes, H.P.; Gefwert, C. & Manthey, M.J.
Partner: UNT Libraries Government Documents Department

3081/E processor and its on-line use

Description: The 3081/E is a second generation emulator of a mainframe IBM. One of it's applications will be to form part of the data acquisition system of the upgraded Mark II detector for data taking at the SLAC linear collider. Since the processor does not have direct connections to I/O devices a FASTBUS interface will be provided to allow communication with both SLAC Scanner Processors (which are responsible for the accumulation of data at a crate level) and the experiment's VAX 8600 mainframe. The 3081/E's will supply a significant amount of on-line computing power to the experiment (a single 3081/E is equivalent to 4 to 5 VAX 11/780's). A major advantage of the 3081/E is that program development can be done on an IBM mainframe (such as the one used for off-line analysis) which gives the programmer access to a full range of debugging tools. The processor's performance can be continually monitored by comparison of the results obtained using it to those given when the same program is run on an IBM computer. 9 refs.
Date: May 1, 1985
Creator: Rankin, P.; Bricaud, B.; Gravina, M.; Kunz, P.F.; Oxoby, G.; Trang, Q. et al.
Partner: UNT Libraries Government Documents Department

Implications for supersymmetry of the CERN monojets

Description: Results of a comprehensive study of supersymmetric processes which could give monojet events similar to those observed at the CERN Sp anti pS are presented. If supersymmetry is to be the explanation of the monojets, strict bounds are obtained on possible supersymmetric masses. 15 references.
Date: January 1, 1985
Creator: Haber, H.E.
Partner: UNT Libraries Government Documents Department

Holonomy anomalies

Description: A new type of anomaly is discussed that afflicts certain non-linear sigma models with fermions. This anomaly is similar to the ordinary gauge and gravitational anomalies since it reflects a topological obstruction to the reparametrization invariance of the quantum effective action. Nonlinear sigma models are constructed based on homogeneous spaces G/H. Anomalies arising when the fermions are chiral are shown to be cancelled sometimes by Chern-Simons terms. Nonlinear sigma models are considered based on general Riemannian manifolds. 9 refs. (LEW)
Date: May 1, 1985
Creator: Bagger, J.; Nemeschansky, D. & Yankielowicz, S.
Partner: UNT Libraries Government Documents Department

Torsion in superstrings

Description: String theories on a background manifold with torsion are discussed. Candidate vacuum configurations are discussed for ten-dimensional superstrings. These are compactified on M/sub 4/ x K, where M/sub 4/ is four-dimensional and K is some compact six-dimensional manifold. Solutions with non-zero torsion on K are emphasized. The compactification problem is approached both from the effective field theory point of view and directly using string considerations. The construction of string theories in curved space with torsion is then discussed. Particular emphasis is put on the constraints on space-time supersymmetry in the Green-Schwarz approach. Two-dimensional non-linear sigma models are used to describe the propagation of strings in background geometries with torsion. (LEW)
Date: September 1, 1985
Creator: Bars, I.; Nemeschansky, D. & Yankielowicz, S.
Partner: UNT Libraries Government Documents Department

Exclusive hadronic and nuclear processes in QCD

Description: Hadronic and nuclear processes are covered, in which all final particles are measured at large invariant masses compared with each other, i.e., large momentum transfer exclusive reactions. Hadronic wave functions in QCD and QCD sum rule constraints on hadron wave functions are discussed. The question of the range of applicability of the factorization formula and perturbation theory for exclusive processes is considered. Some consequences of quark and gluon degrees of freedom in nuclei are discussed which are outside the usual domain of traditional nuclear physics. 44 refs., 7 figs. (LEW)
Date: December 1, 1985
Creator: Brodsky, S.J.
Partner: UNT Libraries Government Documents Department

Finding a rational nomenclature for mesons and baryons

Description: A history of the Particle Data Group's efforts to find a rational and systematic convention for naming mesons and baryons is given. Several versions of our proposal are reviewed, and name changes which would occur are summarized. Some of the mail we have received is described. We hope to stimulate additional feedback.
Date: May 1, 1985
Creator: Barnett, R.M.; Cahn, R.N.; Gidal, G.; Rittenberg, A.; Trippe, T.G.; Wohl, C.G. et al.
Partner: UNT Libraries Government Documents Department

FASTBUS review 1985

Description: The progress of developments based on the FASTBUS Specification DOE/ER-0189 for modular high-speed data acquisition and control systems is reviewed. Available hardware components and efforts in standardized FASTBUS software are summarized. The status of FASTBUS applications at research laboratories in North America is reported. FASTBUS work in Europe and Japan is presented in other papers at this conference. Due to the highly condensed nature of this review, background information and references from reports at the 1983 and 1984 Nuclear Science Symposia may be useful. 17 refs., 4 figs.
Date: September 1, 1985
Creator: Walz, H.V. & Barsotti, E.J.
Partner: UNT Libraries Government Documents Department

FASTBUS for the particle accelerator laboratories

Description: The FASTBUS modular high speed data acquisition and control system for high energy physics and other applications was described by Costrell and Dawson at the 1983 Particle Accelerator Conference. Both the specification and the implementation of this interlaboratory development have progressed considerably since that time. Because of its many attractive features, FASTBUS is currently in use in several major nuclear and high energy physics laboratories and is also finding application in other areas. 10 refs.
Date: May 1, 1985
Creator: Dawson, W.K.; Costrell, L.; Ikeda, H.; Ponting, P.J. & Walz, H.V.
Partner: UNT Libraries Government Documents Department

Applications of the second-order achromat concept to the design of particle accelerators

Description: A property of the second-order achromat, whereby dipole and sextupole families may be inserted into a lattice for chromatic corrections without introducing second-order geometrical (on momentum) optical distortions, has been incorporated in several new particle accelerator designs. These include the SLC at SLAC, LEP at CERN, the EROS pulse stretcher ring at Saskatoon, the CEBAF ring at SURA, and the MIT ring.
Date: May 1, 1985
Creator: Brown, K.L. & Servranckx, R.V.
Partner: UNT Libraries Government Documents Department

SLC positron damping ring optics design

Description: The basic SLAC Linear Collider operation scheme assumes the use of two damping rings, one for the e/sup -/, one for the e/sup +/, in order to reduce the colliding beam normalized emittances to 30 ..pi.. ..mu..radm hence raising the corresponding luminosity by a factor 170. The e/sup -/ damping ring optics, designed by H. Wiedemann, has been extensively studied and modelled since it's completion at the end of 1982. The e/sup +/ damping ring being built will be based on the same design except for some modifications resulting from the studies on the e/sup -/ damping ring which clearly pointed out two major weak points as far as the optics is concerned. The present paper describes the basic modifications of the ring lattice and main equipment positions in order to improve the situation in the Positron Damping Ring. 16 refs., 2 figs., 1 tab.
Date: April 1, 1985
Creator: Delahaye, J.P. & Rivkin, L.
Partner: UNT Libraries Government Documents Department

SLD liquid argon calorimeter prototype test results

Description: The results of the SLD test beam program for the selection of a calorimeter radiator composition within a liquid argon system are described, with emphasis on the study of the use of uranium to obtain equalization of pion and electron responses.
Date: October 1, 1985
Creator: Dubois, R.; Eigen, G.; Au, Y.; Sleeman, J.; Breidenbach, M.; Brau, J. et al.
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

Two photon physics with the Mark II at PEP

Description: Measurements of the mass spectrum and angular distribution of high mass meson pairs produced in ..gamma gamma.. interactions are compared with QCD predictions. The radiative width (GAMMA(eta' ..-->.. ..gamma gamma..) is measured using three different eta' decay modes. Upper limits for the iota radiative width are given.
Date: June 1, 1985
Creator: Gidal, G.
Partner: UNT Libraries Government Documents Department

Two phase cooling for superconducting magnets

Description: A closed circuit tubular cooling system for superconducting magnets offers advantages of limiting boiloff and containing high pressures during quenches. Proper location of automatic valves to lower pressures and protect the refrigerator in the event of quenches is described. Theoretical arguments and exprimental evidence are given against a previously suggested method to determine He two phase flow regimes. If loss of flow occurs due to some types of refrigeration failure and transfer lines have enough heat leak to warm up, quenches are induced when the flow is restored. Examples are taken from experience with the TPC magnet.
Date: August 1, 1985
Creator: Eberhard, P.H.; Gibson, G.A.; Green, M.A.; Ross, R.R.; Smits, R.G.; Taylor, J.D. et al.
Partner: UNT Libraries Government Documents Department