263 Matching Results

Search Results

Advanced search parameters have been applied.

Research in baryon number violation at the superconducting supercollider

Description: This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). One of the most startling events imaginable at a future high-energy collider would be the observation of baryon (B) and lepton (L) number violation. It is surprising that this possibility is not a priori ruled out by our current theoretical understanding of the Standard Model of electroweak forces - despite the best efforts of leading theorists over the last two and one half years. In fact, initial semi-classical calculations using instantons have suggested that, at supercollider-range energies, B- and L-violating processes might occur at an observable rate. Our project has consisted of a theoretical exploration of the possibility of observing B and L violation at future very-high-energy colliders. The techniques developed for addressing this problem should impact more generally on our understanding of weakly-coupled field theories in the non- perturbative regime where both energies and multiplicities are very large. We have made significant progress in our theoretical understanding of anomalous electroweak processes that might be seen at the next generation of supercolliders. With the official cancellation of the Superconducting Supercollider, we have worked to reapply many of these ideas - with great success to date - to the realm of the strong interactions, using Skyrmion methods.
Date: July 1, 1996
Creator: Mattis, M.; Dorey, N.; Silbar, R. & Hughes, J.
Partner: UNT Libraries Government Documents Department

Research and development for the supercollider. Appendix 1

Description: Chairman Fuqua and members of the Subcommitte, I would like to thank you for this opportunity to describe the status of the supercollider research and development program. Over two years have now elapsed since SSC was given the highest priority by the US high energy community. Shortly after, in the fall of 1983, the Department of Energy formally initiated the R&D phase for this potential facility. The developments in the physics world during these past two years have strengthened the arguments for the SSC. Furthermore, the national effort devoted to the SSC R&D during that time has provided us with firm evidence that the SSC can be built with the existing technology and within the cost estimates originally calculated a year and a half ago. I would like to describe for you today some of the accomplishments of this R&D effort and tell you about our plans for the future. I would also like to touch briefly on the important subject of international collaboration. The main objectives of the research and development effort are: (1) to develop and optimize the components necessary for construction of the SSC. Because the magnets are by far the single most expensive and most critical element of the SSC, the major effort during the past two years has been directed in this area; (2) to perform systems tests of the magnets and the associated cryogenic and control systems, and thus to optimize the systems aspects of the proposed machine; (3) to define the requirements that have to be satisfied by potential SSC sites; (4) to prepare a complete conceptual design of the SSC, including a detailed cost estimate, and the projected schedule for the construction, tests and start-up of the whole facility.
Date: October 29, 1985
Creator: Tigner, M.
Partner: UNT Libraries Government Documents Department

Highlights of the SSC Site Development Plan

Description: This paper summarizes highlights of the Site Development Plan for the Superconducting Super Collider Laboratory. The Plan, sometimes called a Master Plan, was prepared by the architectural and engineering firm for the Laboratory: Parsons Brinckerhoff/Morrison Knudsen (PB/MK) working in association with CRSS. Their task was to interpret the SSC project needs in the context of the Ellis County, Texas site. The team effort was under the direction of Lewis May from CRSS, guided by Robert Sims from the SSC Laboratory. Conceptual drawings are presented in this report.
Date: October 1, 1991
Creator: Sanford, J.R.
Partner: UNT Libraries Government Documents Department

Evolution of the rf systems layout for the SSC collider rings

Description: This note contains information on the results of ongoing reviews concerning the basic design of the 360-MHz rf systems for the 2 {times} 20 TeV Superconducting Super Collider (SSC). For generation of 20-MV peak voltage per ring, with proton beams of 2 {times} 70 mA, several versions have been investigated: Version A (baseline design and modified baseline): 2 {times} 8 five-cell normalconducting cavities; Version B: 2 {times} 24 single-cell normalconducting cavities; and Version C: 2 {times} 8 or 2 {times} 10 single-cell superconducting cavities. For reasons of easier High Order Mode (HOM) damping, multicell cavities have been found inferior in performance when compared to single cells. Superconducting cavities have been found superior in handling transient beam loading when compared to normalconducting cavities. A threefold higher voltage, and a reduced R/Q value of superconducting cells lead to a ninefold increase in stored electromagnetic energy which, by the same factor, reduces the speed of phase changes originating from notches in the circulating beams. The theoretical possibility to operate superconducting cavities half-detuned in order to supply reactive power to the beam may also lead to considerable savings in overall power consumption. On the other hand, many challenges are involved with the use of superconducting cavities, such as the delicacy of the superconductive state, the complexity of cryostat design and operation, tuning requirements, sensitivity to vibration, and other issues.
Date: October 1, 1993
Creator: Schaffer, G.
Partner: UNT Libraries Government Documents Department


Description: We have previously reported on the incorporation of a circular boundary condition into the program POISSON for two-dimensional problems (Incorporation of a Circular Boundary Condition into the Program POISSON, S. Caspi, M. Helm, and L.J. Laslett, LBID-887, SSC MAG Note-S, February 13, 1984). The least square method has now been generalized to accept any suitable set of orthogonal functions which can describe the vector potential function outside a circular boundary so located that no external sources are present. We have proceeded to incorporate the boundary condition into cartesian problems which involve no symmetry, and into axis-symmetry cylindrical problems that may have left-right symmetry, antisymmetry or no symmetry.
Date: July 1, 1984
Creator: Caspi, S.; Helm, M. & Laslett, L.J.
Partner: UNT Libraries Government Documents Department

Debunching and Capture in the LEB for the SSC

Description: The authors present the details of the capture process in the Low Energy Booster (LEB) for the SSC. They consider only the longitudinal dynamics. Space charge forces are computed quasistatically. The beam pipe is considered to be perfectly conducting. With respect to maximizing the capture efficiency and minimizing the space charge tune spread, initial few milliseconds are very important. They present only the first few milliseconds of the cycle, during which space charge effects are significant. For the numerical simulation they use the code ESME.
Date: May 1, 1991
Creator: Mahale, N. & Furman, M.
Partner: UNT Libraries Government Documents Department

Pressurized drift tubes scintillating fiber hadron calorimetry. Final report

Description: Under this contract members of the MSU high energy physics group constructed a full-scale Pressurized Drift Tube Chamber intended for the GEM muon system at the SSC. They achieved a position resolution of <90 {mu} over the full 5 m{sup 2} area of the detector. This resolution satisfied the GEM resolution requirements of <100 {mu} by a comfortable margin. Based on their SSC work they developed a new technique for creating wire supports in drift tubes with an overall placement accuracy of <20 {mu}. This technique requires only simple jigging and can be duplicated and operated at low cost. Also, they participated in the design and testing of a hadron calorimeter prototype for GEM. This work lead the authors to develop a semi-automatic welding machine to fuse together two plastic optical fibers. Copies of this machine are currently in use in the CDF endplug upgrade at Fermilab and additional copies are used widely in calorimeter and fiber-tracker construction.
Date: March 22, 1995
Creator: Bromberg, C.; Huston, J. & Miller, R.
Partner: UNT Libraries Government Documents Department

Chaos in Accelerators

Description: Chaos is a general phenomenon in nonlinear dynamical systems. Accelerators--storage rings in particular--in which particles are stored for 10{sup 10} revolutions constitute a particularly intricate nonlinear dynamical system. (In comparison, the earth has revolved around the sun for only 10{sup 9} turns.) Storage rings therefore provide an ideal testing ground for chaos physics. In fact, it is the chaos phenomenon that imposes one of the key design criteria for these accelerators. One might arguably say that the demise of the Superconducting Super Collider project originated from a misjudgement in its chaos analysis at one point along its design path, leading to its first substantial cost escalation. This talk gives an elementary introduction to the study of chaos in accelerators.
Date: May 11, 1999
Creator: Chao, Alex
Partner: UNT Libraries Government Documents Department

Radiation levels in the SSC interaction regions

Description: The radiation environment in a typical SSC detector has been evaluated using the best available particle production models coupled with Monte Carlo simulations of hadronic and electromagnetic cascades. The problems studied include direct charged particle dose, dose inside a calorimeter from the cascades produced by incident photons and hadrons, the flux of neutrons and photons backscattered from the calorimeter into a central cavity, and neutron flux in the calorimeter. The luminosity lifetime at the SSC is dominated by collision losses in the interaction regions, where the luminosity is equivalent to losing an entire full-energy proton beam into the apparatus every six days. The result of an average p-p collision can be described quite simply. The mean charged multiplicity is about 110, and the particles are distributed nearly uniformly in pseudorapidity ({eta}) over all the angles of interest. The transverse momentum distribution is independent of angle, and for our purposes may be written as p{perpendicular}exp(-p{perpendicular}/{beta}). The mean value of p{perpendicular} may be as high as 0.6 GeV/c. Most of the radiation is produced by the very abundant low-p{perpendicular} particles. The dose or neutron fluence produced by individual particles in this energy region are simulated over a wide variety of conditions, and several measurements serve to confirm the simulation results. In general, the response (a dose, fluence, the number of backscattered neutrons, etc.) for an incident particle of momentum p can be parameterized in the form Np{sup {alpha}}, where 0.5 < {alpha}< 1.0. The authors believe most of their results to be accurate to within a factor of two or three, sufficiently precise to serve as the basis for detailed designs.
Date: June 10, 1988
Creator: Groom, D.E.
Partner: UNT Libraries Government Documents Department

Report of the Task Force on Collision Hall Limitations

Description: The Task Force on Collision Hall Limitations met March 23--26, 1987, to obtain a greater understanding of the civil construction requirements for a large scale model SSC detector and to identify limitations, if any, on overall detector scale and individual detector components that may result from civil construction limitations. To this purpose the Task Force studied civil construction techniques and limitations for both deep sites and surface or near surface sites, developed limits and criteria for model detector assembly and servicing, developed a model detector assembly scenario, and estimated an overall schedule from initiation of the design of the experimental hall complex to the completion of the assembly of the model detector. Our conclusions apply only to facilities required to house experiments of the scale of the model detector studied. From our studies it is apparent that the experimental hall complex required for SSC-scale detectors can be constructed under a variety of assumptions regarding the eventual SSC site. There may be significant differences in the schedule and the cost of the experimental hall complex between surface and deep underground locations, with the deep underground, in general, being more expensive and requiring a longer time for construction. The difference in cost and schedule for the experimental facilities for housing the model detector between a surface site and a deep underground site may amount to $25M and two years.
Date: April 1, 1987
Partner: UNT Libraries Government Documents Department

Report of the task force on SSC commissioning and operations

Description: In 1985 January a Taskforce was organized to study the impact of magnet design on the commissioning and operation of the SSC. The results of the study, in the form of this report, are intended as one of several sources of input for the Magnet Type Selection Committee. Other major input will come from the Magnet Taskforce, the Test String Taskforce, the Cost Estimating Taskforce, and other study groups. All of these efforts will culminate in a magnet type selection, after which concentrated R&D on the selected magnet can commence. The study began with a one-week workshop, held on the UC Berkeley campus in 1985 January 14--18. An interim report of the Taskforce, based on the results of the Workshop, was published on 1985 January 28 (SSC-05). With very few exceptions, the work of the Taskforce was carried out by the participants in the Workshop, both during the workshop and in the subsequent weeks. This report is the collective effort of that group, whose very substantial contribution of time, effort, and thought is gratefully acknowledged.
Date: July 1, 1985
Partner: UNT Libraries Government Documents Department

Cost estimate of initial SSC experimental equipment

Description: The cost of the initial detector complement at recently constructed colliding beam facilities (or at those under construction) has been a significant fraction of the cost of the accelerator complex. Because of the complexity of large modern-day detectors, the time-scale for their design and construction is comparable to the time-scale needed for accelerator design and construction. For these reasons it is appropriate to estimate the cost of the anticipated detector complement in parallel with the cost estimates of the collider itself. The fundamental difficulty with this procedure is that, whereas a firm conceptual design of the collider does exist, comparable information is unavailable for the detectors. Traditionally, these have been built by the high energy physics user community according to their perception of the key scientific problems that need to be addressed. The role of the accelerator laboratory in that process has involved technical and managerial coordination and the allocation of running time and local facilities among the proposed experiments. It seems proper that the basic spirit of experimentation reflecting the scientific judgment of the community should be preserved at the SSC. Furthermore, the formal process of initiation of detector proposals can only start once the SSC has been approved as a construction project and a formal laboratory administration put in place. Thus an ad hoc mechanism had to be created to estimate the range of potential detector needs, potential detector costs, and associated computing equipment.
Date: June 1, 1986
Partner: UNT Libraries Government Documents Department

SSC Safety Review Document

Description: The safety strategy of the Superconducting Super Collider (SSC) Central Design Group (CDG) is to mitigate potential hazards to personnel, as far as possible, through appropriate measures in the design and engineering of the facility. The Safety Review Document identifies, on the basis of the Conceptual Design Report (CDR) and related studies, potential hazards inherent in the SSC project independent of its site. Mitigative measures in the design of facilities and in the structuring of laboratory operations are described for each of the hazards identified.
Date: November 1, 1988
Creator: Toohig, T. E.
Partner: UNT Libraries Government Documents Department


Description: This technical basis document was developed to support the documented safety analysis (DSA) and describes the risk binning process and the technical basis for assigning risk bins for natural event hazard (NEH)-initiated accidents. The purpose of the risk binning process is to determine the need for safety-significant structures, systems, and components (SSC) and technical safety requirement (TSR)-level controls for a given representative accident or represented hazardous conditions based on an evaluation of the frequency and consequence. Note that the risk binning process is not applied to facility workers, because all facility worker hazardous conditions are considered for safety-significant SSCs and/or TSR-level controls.
Date: July 31, 2006
Creator: KRIPPS, L.J.
Partner: UNT Libraries Government Documents Department

Improvement of La0.65Sr0.3MnO3-gamma-YSZ cathodes by infiltrating nanoSm0.6Sr0.4CoO3-gamma particles

Description: La0.65Sr0.3MnO3-delta-YSZ cathodes are infiltrated with Sm0.6Sr0.4CoO3-delta (SSC) at 800 C using a precipitation method. The effect of SSC infiltration has been characterized for symmetric cells and single cells at reduced temperatures. With SSC addition the cathode polarization resistance, determined from symmetric-cell measurements, significantly decreases: from approx. 19.8 to 8.5 Omega cdot cm2 at 600 C, and from 7.7 to 3.3 Omega cdot cm2 at 650 C. Consequently, the single-cell performance with 97 percentH2+3 percentH2O fuel is dramatically improved, which may be attributed to the superior electrocatalytic activity of SSC in the cathodes.
Date: May 2004
Creator: Lu, Chun; Sholklapper, Tal; Chen, Xuan; Zhang, Xiaofeng; Jacobson, Craig P.; Visco, Steven J. et al.
Partner: UNT Libraries Government Documents Department

SSC 17-meter dipole magnet DD000Z test results and investigation of coil failure: The report of the {open_quotes}Z{close_quotes} Committee

Description: Following the failure of the lower inner coil of magnet DD000Z on November 3, 1987, a committee was formed on November 11 and given the following charges: `To review the events leading up to and including the failure of the coils of magnet DD000Z. The intent of the review will be to determine the cause of the failure and to make recommendations to reduce the likelihood of such failures in the future. Given the fact that this is the first long magnet to be disassembled, the committee may uncover leads which point to other opportunities for improvement. The committee should follow up on these leads. The committee should prepare a plan to serve as an initial guide for the disassembly and provide guidance as the disassembly progresses.` The committee held its first meeting at FNAL on 17 and 18 Nov to review the record of events leading up to the failure and to establish an initial disassembly procedure. This was followed by further meetings at FNAL, BNL, and CDG, leading to this final report. Committee activities included interviewing personnel who had been involved in the design, assembly and testing of DD000Z, reviewing all documents relating to the magnet and its failure, and participating in and providing guidance during the disassembly. The intention of the committee was to report factual findings, to consider well founded hypotheses, not to consider conjecture and to avoid speculation.
Date: March 1988
Creator: Coombes, R.; Mirk, K.; Tompkins, J.; Zbasnik, J.; Lundy, R.; Schneider, W. et al.
Partner: UNT Libraries Government Documents Department

Calculation of the coupling impedances of holes and slots on the liner using MAFIA and scaling

Description: The location of a liner inside the beam tube is one of the options considered for the Super Colliders. The liner could serve as a synchrotron radiation intercept and also help enhance the vacuum. A definite distribution of holes or slots is required to be located on the liner for pumping out the desorbing gases. There will be wake fields propagating within the liner due to diffraction at discontinuities following the incident beam fields. The effect of these wake fields can be minimized by adopting the least number of pumping holes/slots required and through an optimal choice of hole/slot shape and size. The effect of the wake fields on the beam may be expressed through coupling impedances defined proportional to the corresponding forces integrated through distance per unit charge. It is necessary to compute the impedance of holes and slots and determine the scaling of the impedance with the dimensions of the hole/slot and the liner, in order to optimize the choice of pumping holes/slots. The coupling impedances of slots and holes have been calculated here using the code MAFIA and the scaling assessed. The results compare favorably with existing analytical results.
Date: November 1, 1993
Creator: Thiagarajan, V.; Barts, T.; Kurennoy, S. & Chou, W.
Partner: UNT Libraries Government Documents Department

Coherent production of {epsilon}{sup +} particles in crystal using proton beam from SSC

Description: The unique possibilities of the SSC can be ideally used for a new generation of coherent generation experiments with relativistic protons which require 20 Tev energy of the incident beam. The availability of 20 Tev proton beam at SSC allows new experiments on coherent production of {var_epsilon}{sup +} particle by relativistic proton in crystal. Experiment carried out at low energies can now be extended with protons in very narrow energy region (resonance energy, which easy can be calculated) using the new accelerator facilities at SSC. We propose to study coherent production via the Coulomb field of the cristal atoms to excite the transition p + {gamma}{implies} {var_epsilon} {sup +} (1189).
Date: May 1, 1995
Creator: Okorokov, V.V. & Dubin, A.Yu.
Partner: UNT Libraries Government Documents Department

Collider scenario implications of ASST Operation

Description: After the achievement of the SSCL`s Congressionally Mandated milestone, the Accelerator System String Test (ASST) half cell under went a series of power tests. These tests involved quenches induced in various configurations and in power levels up to the maximum operation point. These tests have produced data which has defined various parameters and requirements for the individual elements and system.
Date: May 1, 1993
Creator: McInturff, A.D.; Burgett, W. & Christianson, M.
Partner: UNT Libraries Government Documents Department