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Sample records for accelerator vacuum system

  1. Vacuum system for Advanced Test Accelerator

    SciTech Connect

    Denhoy, B.S.

    1981-09-03

    The Advanced Test Accelerator (ATA) is a pulsed linear electron beam accelerator designed to study charged particle beam propagation. ATA is designed to produce a 10,000 amp 50 MeV, 70 ns electron beam. The electron beam acceleration is accomplished in ferrite loaded cells. Each cell is capable of maintaining a 70 ns 250 kV voltage pulse across a 1 inch gap. The electron beam is contained in a 5 inch diameter, 300 foot long tube. Cryopumps turbomolecular pumps, and mechanical pumps are used to maintain a base pressure of 2 x 10/sup -6/ torr in the beam tube. The accelerator will be installed in an underground tunnel. Due to the radiation environment in the tunnel, the controlling and monitoring of the vacuum equipment, pressures and temperatures will be done from the control room through a computer interface. This paper describes the vacuum system design, the type of vacuum pumps specified, the reasons behind the selection of the pumps and the techniques used for computer interfacing.

  2. Large high-vacuum systems for CERN accelerators

    NASA Astrophysics Data System (ADS)

    Strubin, P.

    2008-05-01

    CERN operated over the more than 50 years of its existence particle accelerators and storage rings ranging from a few tens of metre to 27 km, the size of its latest project, the Large Hadron Collider (LHC) which is under construction and will be started in 2008. The challenges began with the Intersection Storage Rings (ISR) in the seventies. With a beam pipe length of 2 × 1 km, this accelerator required innovative solutions like bake-out and glow discharge to achieve the required static vacuum level, fight against beam-induced pressure increases and cancel beam neutralisation by trapped electrons. The vacuum system of the Large Electron Positron (LEP) storage ring (in operation between 1989 and 2001) of a total length of 27 km had to cope with very high levels of synchrotron power. The beam vacuum system of LHC (2 × 27 km) integrates some parts at 1.9 K and others at room temperature and will also have to cope with dynamic effects. In addition to the beam vacuum system, LHC requires insulation vacuum for the superconducting magnets and the helium distribution line. Whereas the required pressure is not very low, the leak detection and localisation is significantly more demanding for the insulation vacuum than for the beam vacuum because of the large volumes and the thermal insulation. When the size of an accelerator grows, the difficulties are not only to get a clean and leak tight vacuum system, but also to be able to measure reliably pressure or gas composition over long distances. Furthermore, in the case of LHC the integration of the beam vacuum system was particularly difficult because of the complexity induced by a superconducting magnet scheme and the reduced space available for the beam pipes. Planning and logistics aspects during installation, including the usage of mobile pumping and diagnostic means, were much more difficult to manage in LHC than in previous projects.

  3. Vacuum Systems Consensus Guideline for Department of Energy Accelerator Laboratories

    SciTech Connect

    Casey,R.; Haas, E.; Hseuh, H-C.; Kane, S.; Lessard, E.; Sharma, S.; Collins, J.; Toter, W. F.; Olis, D. R.; Pushka, D. R.; Ladd, P.; Jobe, R. K.

    2008-09-09

    inspections of materials, in-process fabrications, non-destructive tests, and acceptance test. (3) Documentation, traceability, and accountability must be maintained for each unique pressure vessel or system, including descriptions of design, pressure conditions, testing, inspection, operation, repair, and maintenance. The purpose of this guideline is to establish a set of expectations and recommendations which will satisfy the requirements for vacuum vessels in general and particularly when an equivalent level of safety as required by 10 CFR 851 must be provided. It should be noted that these guidelines are not binding on DOE Accelerator Laboratories and that other approaches may be equally acceptable in addressing the Part 851 requirements.

  4. Vacuum system of the 3MeV industrial electron beam accelerator

    NASA Astrophysics Data System (ADS)

    Jayaprakash, D.; Mishra, R. L.; Ghodke, S. R.; kumar, M.; kumar, M.; Nanu, K.; Mittal, K. C., Dr

    2008-05-01

    One DC Accelerator, for electron beam of 3 MeV energy and 10 mA beam current, to derive 30 KW beam power for Industrial applications is nearing completion at Electron Beam Centre, Kharghar, Navi Mumbai. Beam-line of the accelerator is six meters long, consists of electron gun at top, followed by the accelerating column and finally the scan horn. Electron gun and the accelerating column is exposed to SF6 gas at six atmospheres. Area exposed to the vacuum is 65,000 sq: cm, and includes a volume of 200 litres. Vacuum of the order of 1×10-7mbar is desired. To ensure a good vacuum gradient, distributive pumping is implemented. Electron beam is scanned to a size of 5cm × 120cm, to get a useful beam coverage, for industrial radiation applications. The beam is extracted through a window of Titanium foil of 50μm thickness. A safety interlock, to protect the electron gun, accelerating column and sputter ion pumps, in case of a foil rupture, is incorporated. Foil change can be done without disturbing the vacuum in the other zones. System will be integrated to a master control system to take care of the various safety aspects, and to make it operator friendly.

  5. Acquisition of reliable vacuum hardware for large accelerator systems

    SciTech Connect

    Welch, K.M.

    1995-09-06

    Credible and effective communications prove to be the major challenge in the acquisition of reliable vacuum hardware. Technical competence is necessary but not sufficient. The authors must effectively communicate with management, sponsoring agencies, project organizations, service groups, staff and with vendors. Most of Deming`s 14 quality assurance tenants relate to creating an enlightened environment of good communications. All projects progress along six distinct, closely coupled, dynamic phases. All six phases are in a state of perpetual change. These phases and their elements are discussed, with emphasis given to the acquisition phase and its related vocabulary. Large projects require great clarity and rigor as poor communications can be costly. For rigor to be cost effective, it can`t be pedantic. Clarity thrives best in a low-risk, team environment.

  6. Vacuum Brazing of Accelerator Components

    NASA Astrophysics Data System (ADS)

    Singh, Rajvir; Pant, K. K.; Lal, Shankar; Yadav, D. P.; Garg, S. R.; Raghuvanshi, V. K.; Mundra, G.

    2012-11-01

    Commonly used materials for accelerator components are those which are vacuum compatible and thermally conductive. Stainless steel, aluminum and copper are common among them. Stainless steel is a poor heat conductor and not very common in use where good thermal conductivity is required. Aluminum and copper and their alloys meet the above requirements and are frequently used for the above purpose. The accelerator components made of aluminum and its alloys using welding process have become a common practice now a days. It is mandatory to use copper and its other grades in RF devices required for accelerators. Beam line and Front End components of the accelerators are fabricated from stainless steel and OFHC copper. Fabrication of components made of copper using welding process is very difficult and in most of the cases it is impossible. Fabrication and joining in such cases is possible using brazing process especially under vacuum and inert gas atmosphere. Several accelerator components have been vacuum brazed for Indus projects at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore using vacuum brazing facility available at RRCAT, Indore. This paper presents details regarding development of the above mentioned high value and strategic components/assemblies. It will include basics required for vacuum brazing, details of vacuum brazing facility, joint design, fixturing of the jobs, selection of filler alloys, optimization of brazing parameters so as to obtain high quality brazed joints, brief description of vacuum brazed accelerator components etc.

  7. K-130 Cyclotron vacuum system

    NASA Astrophysics Data System (ADS)

    Yadav, R. C.; Bhattacharya, S.; Bhole, R. B.; Roy, Anindya; Pal, Sarbajit; Mallik, C.; Bhandari, R. K.

    2012-11-01

    The vacuum system for K-130 cyclotron has been operational since 1977. It consists of two sub-systems, main vacuum system and beam line vacuum system. The main vacuum system is designed to achieve and maintain vacuum of about 1 × 10-6 mbar inside the 23 m3 volume of acceleration chamber comprising the Resonator tank and the Dee tank. The beam line vacuum system is required for transporting the extracted beam with minimum loss. These vacuum systems consist of diffusion pumps backed by mechanical pumps like roots and rotary pumps. The large vacuum pumps and valves of the cyclotron vacuum system were operational for more than twenty five years. In recent times, problems of frequent failures and maintenance were occurring due to aging and lack of appropriate spares. Hence, modernisation of the vacuum systems was taken up in order to ensure a stable high voltage for radio frequency system and the extraction system. This is required for efficient acceleration and transportation of high intensity ion beam. The vacuum systems have been upgraded by replacing several pumps, valves, gauges and freon units. The relay based control system for main vacuum system has also been replaced by PLC based state of the art control system. The upgraded control system enables inclusion of additional operational logics and safety interlocks into the system. The paper presents the details of the vacuum system and describes the modifications carried out for improving the performance and reliability of the vacuum system.

  8. High Power Proton Accelerator Development at KAERI and its Vacuum System

    NASA Astrophysics Data System (ADS)

    Choi, Byung-Ho; Park, Mi Young; Kim, Kui Young; Kim, Kye Ryung; Kim, Jun Yeon; Cho, Yong-Sub

    The Proton Engineering Frontier Project (PEFP), approved and launched by the Korean government in July 2002, includes a 100 MeV proton linear accelerator (linac) development and programs for its utilization and application. The main goals in the first phase of the project, spanning from 2002 to 2005, were the design of a 100 MeV proton linac and the development of a 20 MeV linac consisting of a 50 keV proton injector, a 3 MeV radio frequency quadrupole (RFQ), and a 20 MeV drift tube linac (DTL). The 50 keV injector and 3 MeV RFQ have been installed and tested, and the 20 MeV DTL is being assembled, tuned and under a beam test. At the same time, the utilization programs using the proton beam have been planned, and some are now under way. The vacuum system of the 20 MeV proton linac and its related issues, especially in operation with a high duty, are discussed in detail.

  9. An automated vacuum system

    SciTech Connect

    Atkins, W.H. ); Vaughn, G.D. ); Bridgman, C. )

    1991-01-01

    Software tools available with the Ground Test Accelerator (GTA) control system provide the capability to express a control problem as a finite state machine. System states and transitions are expressed in terms of accelerator parameters and actions are taken based on state transitions. This is particularly useful for sequencing operations which are modal in nature or are unwieldy when implemented with conventional programming. State diagrams are automatically translated into code which is executed by the control system. These tools have been applied to the vacuum system for the GTA accelerator to implement automatic sequencing of operations. With a single request, the operator may initiate a complete pump-down sequence. He can monitor the progress and is notified if an anomaly occurs requiring intervention. The operator is not required to have detailed knowledge of the vacuum system and is protected from taking inappropriate actions. 1 ref., 6 figs.

  10. ISABELLE vacuum systems

    SciTech Connect

    Halama, H J

    1980-01-01

    The Intersecting Storage Accelerator (ISABELLE) consists of two rings having a circumference of 3.8 km each. In these rings superconducting magnets, held at 4 K, bend and focus the proton beam which is accelerated up to 400 GeV. Due to very different pressure requirements, ISABELLE has two completely independent vacuum systems. One, which operates at 1 x 10/sup -11/ Torr, provides a very clean environment for the circulating proton beam. Here only ion and titanium sublimation pumps are used to provide the vacuum. The other system maintains superconducting magnet vessels at a pressure below 1 x 10/sup -4/ Torr, since at this pressure the gas conduction becomes negligible. In this so-called insulating vacuum system, turbomolecular pumps pump the inadvertent small helium leaks. Other gases are cryocondensed on the cold surfaces of the cryogenic system. The basic element of ISABELLE known as Full Cell containing 45 meters of beam tube, 8 pumping stations, 8 superconducting magnets and complete instrumentation has been constructed, leak checked and tested. All design parameters have been achieved in both vacuum systems. The two vacuum systems are described with particular emphasis on the influence of superconducting magnets in the selection of materials and UHV components.

  11. Ultra-high vacuum photoelectron linear accelerator

    DOEpatents

    Yu, David U.L.; Luo, Yan

    2013-07-16

    An rf linear accelerator for producing an electron beam. The outer wall of the rf cavity of said linear accelerator being perforated to allow gas inside said rf cavity to flow to a pressure chamber surrounding said rf cavity and having means of ultra high vacuum pumping of the cathode of said rf linear accelerator. Said rf linear accelerator is used to accelerate polarized or unpolarized electrons produced by a photocathode, or to accelerate thermally heated electrons produced by a thermionic cathode, or to accelerate rf heated field emission electrons produced by a field emission cathode.

  12. The RHIC vacuum systems

    NASA Astrophysics Data System (ADS)

    Burns, R.; Hseuh, H. C.; Lee, R. C.; McIntyre, G.; Pate, D.; Smart, L.; Sondericker, J.; Weiss, D.; Welch, K.

    2003-03-01

    There are three vacuum systems in RHIC: the insulating vacuum vessels housing the superconducting magnets, the cold beam tubes surrounded by the superconducting magnets, and the warm beam tube sections at the insertion regions and the experimental regions. These systems have a cumulative length over 10 km and a total volume over 3000 m 3. Conventional ultrahigh vacuum technology was used in the design and construction of the cold and warm beam vacuum systems with great success. The long and large insulating vacuum volumes without vacuum barriers require careful management of the welding and leak checking of the numerous helium line joints. There are about 1500 vacuum gauges and pumps serial-linked to eight PLCs distributed around RHIC, which allow the monitoring and control of these devices through Ethernet networks to remote control consoles. With the exception of helium leaks through the cryogenic valve boxes into the insulating vacuum volumes, the RHIC vacuum systems have performed well beyond expectations.

  13. Vacuum Insulator Development for the Dielectric Wall Accelerator

    SciTech Connect

    Harris, J R; Blackfield, D; Caporaso, G J; Chen, Y; Hawkins, S; Kendig, M; Poole, B; Sanders, D M; Krogh, M; Managan, J E

    2008-03-17

    At Lawrence Livermore National Laboratory, we are developing a new type of accelerator, known as a Dielectric Wall Accelerator, in which compact pulse forming lines directly apply an accelerating field to the beam through an insulating vacuum boundary. The electrical strength of this insulator may define the maximum gradient achievable in these machines. To increase the system gradient, we are using 'High Gradient Insulators' composed of alternating layers of dielectric and metal for the vacuum insulator. In this paper, we present our recent results from experiment and simulation, including the first test of a High Gradient Insulator in a functioning Dielectric Wall Accelerator cell.

  14. EM Structure Based and Vacuum Acceleration

    SciTech Connect

    Colby, E.R.; /SLAC

    2005-09-27

    The importance of particle acceleration may be judged from the number of applications which require some sort of accelerated beam. In addition to accelerator-based high energy physics research, non-academic applications include medical imaging and treatment, structural biology by x-ray diffraction, pulse radiography, cargo inspection, material processing, food and medical instrument sterilization, and so on. Many of these applications are already well served by existing technologies and will profit only marginally from developments in accelerator technology. Other applications are poorly served, such as structural biology, which is conducted at synchrotron radiation facilities, and medical treatment using proton accelerators, the machines for which are rare because they are complex and costly. Developments in very compact, high brightness and high gradient accelerators will change how accelerators are used for such applications, and potentially enable new ones. Physical and technical issues governing structure-based and vacuum acceleration of charged particles are reviewed, with emphasis on practical aspects.

  15. Numerical Study of Virtual Cathode Behavior in Vacuum Collective Ion Acceleration Systems.

    NASA Astrophysics Data System (ADS)

    Grossmann, John Mark

    The behavior of an intense relativistic beam of electrons injected into a cylindrical conducting drift tube is investigated with the aid of an electrostatic simulation code. The relevance of such a study is in linear beam, evacuated drift tube systems where high energy ions are observed when the beam interacts with a source of ions. In our numerical study, the beam's motion is assumed to be purely one dimensional; however, the electric field is solved in two dimensions using special "method of lines" techniques. One of the two principal techniques is developed to accurately resolve the extreme local gradients in charge density and potential existing in the drift tube. It is a Galerkin solution of Poisson's equation on a non-uniform mesh and has an operations count of O(N('2)) and convergence rate in energy norm of O(1/N). The other O(N log(,N)N) technique uses FFT methods on a uniform mesh and converges in uniform norm O(1/N('2)). It is found that when the injected current of the beam is above a threshold or limiting value the beam-drift tube system reacts by abruptly forming a dense clump of electrons near the injection end of the tube. This clump prevents the steady flow of electrons downstream and is called a virtual cathode (VC). A detailed picture of the VC formation process is provided by our simulations, together with a display of the dynamic behavior of the VC at various injection currents and parameter regimes. The VC oscillates in well depth and position at about the plasma frequency of the dense clump of electrons. The potential at the clump oscillates between (phi)(,0) and 1.6 (phi)(,0) where (phi)(,0) is the energy of the injected electrons. In addition, the VC sprays a group of electrons downstream every plasma period in such a manner that the average current associated with the stream is close to the limiting current. Peak electric fields at the anode are in the range 200-600 MV/m for our system parameters. Finally, a preliminary investigation is

  16. Chirped pulse inverse free-electron laser vacuum accelerator

    DOEpatents

    Hartemann, Frederic V.; Baldis, Hector A.; Landahl, Eric C.

    2002-01-01

    A chirped pulse inverse free-electron laser (IFEL) vacuum accelerator for high gradient laser acceleration in vacuum. By the use of an ultrashort (femtosecond), ultrahigh intensity chirped laser pulse both the IFEL interaction bandwidth and accelerating gradient are increased, thus yielding large gains in a compact system. In addition, the IFEL resonance condition can be maintained throughout the interaction region by using a chirped drive laser wave. In addition, diffraction can be alleviated by taking advantage of the laser optical bandwidth with negative dispersion focusing optics to produce a chromatic line focus. The combination of these features results in a compact, efficient vacuum laser accelerator which finds many applications including high energy physics, compact table-top laser accelerator for medical imaging and therapy, material science, and basic physics.

  17. RF cavity vacuum interlock system

    NASA Astrophysics Data System (ADS)

    Jordan, K.; Crawford, K.; Bundy, R.; Dylla, H. F.; Heckman, J.; Marshall, J.; Nichols, R.; Osullivan, S.; Preble, J.; Robb, J.

    1992-03-01

    The Continuous Electron Beam Accelerator Facility (CEBAF), a continuous wave (CW) 4 GeV Electron Accelerator is undergoing construction in Newport News, Virginia. When completed in 1994, the accelerator will be the largest installation of radio-frequency superconductivity. Production of cryomodules, the fundamental building block of the machine, has started. A cryomodule consists of four sets of pairs of 1497 MHz, 5 cell niobium cavities contained in separate helium vessels and mounted in a cryostat with appropriate end caps for helium supply and return. Beam vacuum of the cavities, the connecting beam piping, the waveguides, and the cryostat insulating vacuum are crucial to the performance of the machine. The design and initial experience of the vacuum systems for the first 2 1/4 cryomodules that makeup the 45 MEV injector are discussed.

  18. Laser driven acceleration in vacuum and gases

    SciTech Connect

    Sprangle, P.; Esarey, E.; Hafizi, B.; Hubbard, R.; Krall, J.; Ting, A.

    1997-03-01

    Several important issues pertaining to particle acceleration in vacuum and gases are discussed. The limitations of laser vacuum acceleration as they relate to electron slippage, laser diffraction, material damage, and electron aperture effects are presented. Limitations on the laser intensity and particle self-fields due to material breakdown are quantified. In addition, the reflection of the self-fields associated with the accelerated particles places a limit on the number of particles. Two configurations for the inverse Cherenkov accelerator (ICA) are considered, in which the electromagnetic driver is propagated in a waveguide that is (i) lined with a dielectric material or (ii) filled with a neutral gas. The acceleration gradient in the ICA is limited by tunneling and collisional ionization in the dielectric liner or gas. Ionization can lead to significant modification of the optical properties of the waveguide, altering the phase velocity and causing particle slippage, thus disrupting the acceleration process. Maximum accelerating gradients and pulse durations are presented for a 10 {mu}m and a 1 mm wavelength driver. We show that the use of an unguided Bessel (axicon) beam can enhance the energy gain compared to a higher order Gaussian beam. The enhancement factor is N{sup 1/2}, where N is the number of lobes in the Bessel beam. {copyright} {ital 1997 American Institute of Physics.}

  19. NSLS II Vacuum System

    SciTech Connect

    Ferreira, M.; Doom, L.; Hseuh, H.; Longo, C.; Settepani, P.; Wilson, K.; Hu, J.

    2009-09-13

    National Synchrotron Light Source II, being constructed at Brookhaven, is a 3-GeV, 500 mA, 3rd generation synchrotron radiation facility with ultra low emittance electron beams. The storage ring vacuum system has a circumference of 792 m and consists of over 250 vacuum chambers with a simulated average operating pressure of less than 1 x 10{sup -9} mbar. A summary of the update design of the vacuum system including girder supports of the chambers, gauges, vacuum pumps, bellows, beam position monitors and simulation of the average pressure will be shown. A brief description of the techniques and procedures for cleaning and mounting the chambers are given.

  20. Prototype of a tubeless vacuum insulated accelerator

    NASA Astrophysics Data System (ADS)

    Boggia, A.; Brautti, G.; Raino, A.; Stagno, V.; Ceci, N.; Valentino, V.; Variale, V.

    1996-02-01

    The construction of a small prototype of a new kind of Cockroft-Walton accelerator is in progress. The onion-wise disposal of the capacitor plates allows a high-gradient compact machine, as well as the assurance of reliability. This kind of machine can overcome the problem of having an accelerating column of high perveance. In fact, because of its peculiar electromechanical structure, the whole high voltage generator can be settled inside a vacuum chamber and then an electron beam can be accelerated directly by the capacitor plates of the voltage multipliers. The scaled-up version of this machine seems to be particularly suited for high-current, high-efficiency applications, like FEL, ion acceleration for plasma heating or containment. The status report of the experiment will be presented.

  1. Vacuum electron acceleration by an intense laser

    SciTech Connect

    Wang, P.X.; Ho, Y.K.; Yuan, X.Q.; Kong, Q.; Sessler, A.M.; Esarey, E.; Nishida, Y.

    2001-01-12

    Using 3D test particle simulations, the characteristics and essential conditions under which an electron, in a vacuum laser beam, can undergo a capture and acceleration scenario (CAS). When a{sub 0} {approx}> 100 the electron can be captured and violently accelerated to energies {approx}> 1 GeV, with an acceleration gradient {approx}> 10 GeV/cm, where a{sub 0} = eE{sub 0}/m{sub e}{omega}c is the normalized laser field amplitude. The physical mechanism behind the CAS is that diffraction of the focused laser beam leads to a slowing down of the effective wave phase velocity along the captured electron trajectory, such that the electron can be trapped in the acceleration phase of the wave for a longer time and thus gain significant energy from the field.

  2. Technical specification for vacuum systems

    SciTech Connect

    Khaw, J.

    1987-01-01

    The vacuum systems at the Stanford Linear Accelerator Center (SLAC) are primarily of all-metal construction and operate at pressures from 10/sup -5/ to 10/sup -11/ Torr. The primary gas loads during operation result from thermal desorption and beam-induced desorption from the vacuum chamber walls. These desorption rates can be extremely high in the case of hydrocarbons and other contaminants. These specifications place a major emphasis on eliminating contamination sources. The specifications and procedures have been written to insure the cleanliness and vacuum integrity of all SLAC vacuum systems, and to assist personnel involved with SLAC vacuum systems in choosing and designing components that are compatible with existing systems and meet the quality and reliability of SLAC vacuum standards. The specification includes requirements on design, procurement, fabrication, chemical cleaning, clean room practices, welding and brazing, helium leak testing, residual gas analyzer testing, bakeout, venting, and pumpdown. Also appended are specifications regarding acceptable vendors, isopropyl alcohol, bakeable valve cleaning procedure, mechanical engineering safety inspection, notes on synchrotron radiation, and specifications of numerous individual components. (LEW)

  3. Vacuum deposition system

    SciTech Connect

    Austin, S.; Bark, D.

    1990-05-31

    The Physics Section vacuum deposition system is available for several types of thin film techniques. This vacuum evaporation system operates in the high vacuum range. The evaporation source is a resistive heating element, either a boat or a filament design. Coating is then line of sight from the source. Substrates to be coated can have a maximum diameter of 17 inches. At this time the variations in the thickness of the coatings can be controlled, by monitor, to within about 100 angstroms. The system diagrams follow the Operation Procedures and the Sample Coating Procedures provided in this document. 3 figs.

  4. Accelerated life test of the USDOE OC-OTEC experimental system refurbished with magnetic bearings for the 3rd stage vacuum compressor. Final report

    SciTech Connect

    Vega, L.A.

    1997-04-01

    This report documents the accelerated life test (time-to-failure) performed, at the request of DOE, to evaluate the viability of the magnetic bearing system installed in the stage 3 vacuum pump. To this effect the plant was successfully operated for over 500 hours during the period September-November 1996. The first part of this report discusses system performance by deriving subsystem and system performance parameters from a typical record. This is followed by the discussion of the life tests. The instrumentation used to estimate the performance parameters given here is depicted. The third stage pump was operated for 535 hours without incident. It is concluded that magnetic bearings are the preferable choice for the OC-OTEC centrifugal vacuum pumps.

  5. Tara vacuum system

    SciTech Connect

    Post, R.S.; Brindza, P.; Goodrich, P.; Gaudreau, M.P.

    1985-11-01

    The Tara tandem mirror experiment vacuum system will be discussed including system design, specifications, and performance required for plug thermal barrier operation. A detailed description of the major pumpig systems, reflux control, plasma pumping, measurement and control, fast gas handling and quality control procedures will be presented. Data from the two 5 month periods of operation will be presented.

  6. Insertion device vacuum system designs

    SciTech Connect

    Hoyer, E.

    1988-05-01

    Synchrotron light source insertion device vacuum systems now in operation and systems proposed for the future are reviewed. An overview of insertion devices is given and four generic vacuum chamber designs, transition section design and pumping considerations are discussed. Examples of vacuum chamber systems are presented.

  7. Tritium handling in vacuum systems

    SciTech Connect

    Gill, J.T.; Coffin, D.O.

    1986-10-01

    This report provides a course in Tritium handling in vacuum systems. Topics presented are: Properties of Tritium; Tritium compatibility of materials; Tritium-compatible vacuum equipment; and Tritium waste treatment.

  8. Laser driven electron acceleration in vacuum, gases and plasmas

    SciTech Connect

    Sprangle, P.; Esarey, E.; Krall, J.

    1996-04-19

    This paper discusses some of the important issues pertaining to laser acceleration in vacuum, neutral gases and plasmas. The limitations of laser vacuum acceleration as they relate to electron slippage, laser diffraction, material damage and electron aperture effects, are discussed. An inverse Cherenkov laser acceleration configuration is presented in which a laser beam is self guided in a partially ionized gas. Optical self guiding is the result of a balance between the nonlinear self focusing properties of neutral gases and the diffraction effects of ionization. The stability of self guided beams is analyzed and discussed. In addition, aspects of the laser wakefield accelerator are presented and laser driven accelerator experiments are briefly discussed.

  9. Advanced Photon Source accelerator ultrahigh vacuum guide

    SciTech Connect

    Liu, C.; Noonan, J.

    1994-03-01

    In this document the authors summarize the following: (1) an overview of basic concepts of ultrahigh vacuum needed for the APS project, (2) a description of vacuum design and calculations for major parts of APS, including linac, linac waveguide, low energy undulator test line, positron accumulator ring (PAR), booster synchrotron ring, storage ring, and insertion devices, and (3) cleaning procedures of ultrahigh vacuum (UHV) components presently used at APS.

  10. Understand vacuum-system fundamentals

    SciTech Connect

    Martin, G.R. ); Lines, J.R. ); Golden, S.W. )

    1994-10-01

    Crude vacuum unit heavy vacuum gas-oil (HVGO) yield is significantly impacted by ejector-system performance, especially at conditions below 20 mmHg absolute pressure. A deepcut vacuum unit, to reliably meet the yields, calls for proper design of all the major pieces of equipment. Ejector-system performance at deepcut vacuum column pressures may be independently or concurrently affected by: atmospheric column overflash, stripper performance or cutpoint; vacuum column top temperature and heat balance; light vacuum gas-oil (LVGO) pumparound entrainment to the ejector system; cooling-water temperature; motive steam pressure; non-condensible loading, either air leakage or cracked light-end hydrocarbons; condensible hydrocarbons; intercondenser or aftercondenser fouling ejector internal erosion or product build-up; and system vent back pressure. The paper discusses gas-oil yields; ejector-system fundamentals; condensers; vacuum-system troubleshooting; process operations; and a case study of deepcut operations.

  11. Laser Acceleration in Vacuum and Gases with Capillary Waveguide

    SciTech Connect

    Xie, Ming

    1999-02-01

    A unified framework is developed to overcome all three major limitations on acceleration and distance and hence on the feasibility of two classes of laser acceleration. The three limitations are due to laser diffraction, acceleration phase slippage, and structure damage by high power laser if solid-state optical waveguide is used. The two classes of laser acceleration are direct-field acceleration and ponderomotive-driven acceleration. Thus this letter and its companion [1] provide solutions that are crucial to all mainstream approaches for laser acceleration, either in vacuum, gases or plasmas.

  12. Vacuum Insulator Studies for the Dielectric Wall Accelerator

    SciTech Connect

    Harris, J R; Chen, Y J; Blackfield, D; Sanders, D M; Caporaso, G J; Krogh, M

    2007-06-11

    As part of our ongoing development of the Dielectric Wall Accelerator, we are studying the performance of multilayer high-gradient insulators. These vacuum insulating structures are composed of thin, alternating layers of metal and dielectric, and have been shown to withstand higher gradients than conventional vacuum insulator materials. This paper describes these structures and presents some of our recent results.

  13. Laser acceleration in vacuum, gases, and plasmas withcapillary waveguide

    SciTech Connect

    Xie, Ming

    1998-07-01

    I propose a new method for laser acceleration of relativistic electrons using the leaky modes of a hollow dielectric waveguide. The hollow core of the waveguide can be either in vacuum or filled with uniform gases or plasmas. In case of vacuum and gases, TM01 mode is used for direct acceleration. In case of plasmas, EH11 mode is used to drive longitudinal plasma wave for acceleration. Structure damage due to high power laser can be avoided by choosing a core radius sufficiently larger than laser wavelength. Effect of nonuniform plasma density on waveguide performance is also analyzed.

  14. Capillary waveguide for laser acceleration in vacuum, gases and plasmas

    SciTech Connect

    Xie, Ming

    1998-06-01

    The authors propose a new method for laser acceleration of relativistic electrons using the leaky modes of a hollow dielectric waveguide. The hollow core of the waveguide can be either in vacuum or filled with uniform gases or plasmas. In of vacuum and gases, TM{sub 01} mode is used for direct acceleration. In case of plasmas, EH{sub 11} mode is used to drive longitudinal plasma wave for acceleration. Structure damage by high power laser is avoided by choosing a core radius much larger than laser wavelength.

  15. Vacuum laser acceleration of relativistic electrons using plasma mirror injectors

    NASA Astrophysics Data System (ADS)

    Thévenet, M.; Leblanc, A.; Kahaly, S.; Vincenti, H.; Vernier, A.; Quéré, F.; Faure, J.

    2016-04-01

    Accelerating particles to relativistic energies over very short distances using lasers has been a long-standing goal in physics. Among the various schemes proposed for electrons, vacuum laser acceleration has attracted considerable interest and has been extensively studied theoretically because of its appealing simplicity: electrons interact with an intense laser field in vacuum and can be continuously accelerated, provided they remain at a given phase of the field until they escape the laser beam. But demonstrating this effect experimentally has proved extremely challenging, as it imposes stringent requirements on the conditions of injection of electrons in the laser field. Here, we solve this long-standing experimental problem by using a plasma mirror to inject electrons in an ultraintense laser field, and obtain clear evidence of vacuum laser acceleration. With the advent of petawatt lasers, this scheme could provide a competitive source of very high charge (nC) and ultrashort relativistic electron beams.

  16. Multipurpose Vacuum Induction Processing System

    NASA Astrophysics Data System (ADS)

    Govindaraju, M.; Kulkarni, Deepak; Balasubramanian, K.

    2012-11-01

    Multipurpose vacuum processing systems are cost effective; occupy less space, multiple functional under one roof and user friendly. A multipurpose vacuum induction system was designed, fabricated and installed in a record time of 6 months time at NFTDC Hyderabad. It was designed to function as a) vacuum induction melting/refining of oxygen free electronic copper/pure metals, b) vacuum induction melting furnace for ferrous materials c) vacuum induction melting for non ferrous materials d) large vacuum heat treatment chamber by resistance heating (by detachable coil and hot zone) e) bottom discharge vacuum induction melting system for non ferrous materials f) Induction heat treatment system and g) directional solidification /investment casting. It contains provision for future capacity addition. The attachments require to manufacture multiple shaped castings and continuous rod casting can be added whenever need arises. Present capacity is decided on the requirement for 10years of development path; presently it has 1.2 ton liquid copper handling capacity. It is equipped with provision for capacity addition up to 2 ton liquid copper handling capacity in future. Provision is made to carry out the capacity addition in easy steps quickly. For easy operational maintenance and troubleshooting, design was made in easily detachable sections. High vacuum system is also is detachable, independent and easily movable which is first of its kind in the country. Detailed design parameters, advantages and development history are presented in this paper.

  17. Generation of nanosecond neutron pulses in vacuum accelerating tubes

    NASA Astrophysics Data System (ADS)

    Didenko, A. N.; Shikanov, A. E.; Rashchikov, V. I.; Ryzhkov, V. I.; Shatokhin, V. L.

    2014-06-01

    The generation of neutron pulses with a duration of 1-100 ns using small vacuum accelerating tubes is considered. Two physical models of acceleration of short deuteron bunches in pulse neutron generators are described. The dependences of an instantaneous neutron flux in accelerating tubes on the parameters of pulse neutron generators are obtained using computer simulation. The results of experimental investigation of short-pulse neutron generators based on the accelerating tube with a vacuum-arc deuteron source, connected in the circuit with a discharge peaker, and an accelerating tube with a laser deuteron source, connected according to the Arkad'ev-Marx circuit, are given. In the experiments, the neutron yield per pulse reached 107 for a pulse duration of 10-100 ns. The resultant experimental data are in satisfactory agreement with the results of computer simulation.

  18. HESYRL storage ring vacuum system

    SciTech Connect

    Li, G.; Pang, Y.; Wang, Y.; Zhou, H.; Zhang, Z.; Jiang, D.; Xu, B.; Xu, S.

    1988-09-30

    The Storage Ring Vacuum System of the Synchrotron Radiation source project of HESYRL (Hefei Synchrotron Radiation Laboratory) in USTC, Hefei, Anhui, China, will be completed this year. Since the designed beam current of the 800 MeV electron storage ring is 300 mA, synchrotron radiation and hence high photon stimulated degassing will occur in the vacuum chamber. In order to get the stored beam lifetime of several hours, the pressure must be maintained at 10/sup -8/ approx.10/sup -9/ Torr. The gas desorption from synchrotron radiation and thermal outgas has been calculated. The UHV system of the storage ring and vacuum pretreatment methods are described in this paper.

  19. Phase motion of accelerated electrons in vacuum laser acceleration

    SciTech Connect

    Hua, J. F.; Lin, Y. Z.; Tang, Ch. X.; Ho, Y. K.; Kong, Q.

    2007-01-15

    The phase stability in the capture and acceleration scenario (CAS) is studied and compared with that of conventional linear electron accelerators (CLEAs). For the CAS case, it has been found that a slow phase slippage occurs due to the difference between the electron velocity and the phase velocity of the longitudinal accelerating electric field. Thus, CAS electrons cannot remain in a fixed small phase region of the accelerating field to obtain a quasimonoenergy gain in contrast to the stability of phase oscillation in CLEAs. Also, the energy spread of the output electron beam for the CAS case cannot be kept as small as the CLEA because there is no good phase bunching phenomenon generated by phase oscillation.

  20. The LHC Vacuum System

    NASA Astrophysics Data System (ADS)

    Gröbner, O.

    1997-05-01

    The Large Hadron Collider (LHC) at CERN, involves two proton storage rings with colliding beams of 7 TeV. The machine will be housed in the existing LEP tunnel and requires 16 m long superconducting bending magnets. The vacuum chamber will be the inner wall of the cryostat and hence at the temperature of the magnet cold bore, i.e. at 1.9 K and therefore a very good cryo-pump. To reduce the cryogenic power consumption, the heat load from synchrotron radiation and from the image currents in the vacuum chamber will be absorbed on a 'beam screen', which operates between 5 and 20 K, inserted in the magnet cold bore. The design pressure necessary for operation must provide a lifetime of many days and a stringent requirement comes from the power deposition in the superconducting magnet coils due to protons scattered on the residual gas which could lead to a magnet quench. Cryo-pumping of gas on the cold surfaces provides the necessary low gas densities but it must be ensured that the vapour pressure of cryo-sorbed molecules, of which H2 and He would be the most critical species, remains within acceptable limits. The room temperature sections of the LHC, specifically in the experiments, the vacuum must be stable against ion induced desorption and ISR-type 'pressure bumps'.

  1. Electron acceleration using two crossed Bessel beams in vacuum

    NASA Astrophysics Data System (ADS)

    Zhao, Zhiguo; Lü, Baida

    2007-09-01

    The direct acceleration of electrons by using two crossed linearly polarized Bessel beams with equal frequency and amplitude in vacuum is studied and compared with the case of single linearly polarized Bessel beam. It is found that two zeroth- and first-order Bessel beams with π-rad phase difference have a nonvanishing longitudinal electric field on the z-axis, which can be maximized under certain conditions and used to accelerate electrons. Two crossed zeroth- and first-order Bessel beams have a larger maximum longitudinal electric field on the z-axis than that of a single first-order Bessel beam, and are suited for laser electron acceleration.

  2. Vacuum system pump down analysis

    SciTech Connect

    Rohrdanz, D.R.

    1990-08-01

    My assignment on the SP-100 Vacuum Vessel Vacuum System Team was to perform a transient pump down analysis for the vacuum vessel that will house the SP-100 reactor during testing. Pump down time was calculated for air and helium. For all cases the proposed vacuum system will be able to pump down the vessel within the required time. The use of a larger rotary piston pump (DUO250) improves the pump down time by 35 minutes and therefore should be considered. The 6-inch duct for the roughing line is optimal, however, because all cases are well below the 24 hour time frame, the 4-inch duct is sufficient. The use of the single turbomolecular pump during pump down is sufficient. A pump down with helium in the vessel and a helium inleakage delays the time to achieve the base pressure marginally and is acceptable.

  3. Testing of vacuum pumps for the Accelerator Production of Tritium/Low Energy Demonstration Accelerator radio frequency quadrupole

    SciTech Connect

    Kishiyama, K.; Shen, S.; Behne, D.; Wilson, N.G.; Schrage, D.; Valdiviez, R.

    1998-12-31

    Two vacuum systems were designed and built for the RFQ (Radio Frequency Quadrupole) cavity in the APT/LEDA (Low Energy Demonstration Accelerator) linac. The gas load from the proton beam required very high hydrogen pump speed and capacity. The gas load from the high power RF windows also required very high hydrogen pump speed for the RF window vacuum system. Cryopumps were chosen for the RFQ vacuum system and ST185 sintered non-evaporable getter (NEG) cartridges were chosen for the RF window vacuum system. Hydrogen pump speed and capacity measurements were carried out for a commercial cryopump and a NEG pump. This paper will discuss the test procedures and the results of the measurements.

  4. Cold cathode vacuum gauging system

    DOEpatents

    Denny, Edward C.

    2004-03-09

    A vacuum gauging system of the cold cathode type is provided for measuring the pressure of a plurality of separate vacuum systems, such as in a gas centrifuge cascade. Each casing is fitted with a gauge tube assembly which communicates with the vacuum system in the centrifuge casing. Each gauge tube contains an anode which may be in the form of a slender rod or wire hoop and a cathode which may be formed by the wall of the gauge tube. The tube is provided with an insulated high voltage connector to the anode which has a terminal for external connection outside the vacuum casing. The tube extends from the casing so that a portable magnet assembly may be inserted about the tube to provide a magnetic field in the area between the anode and cathode necessary for pressure measurements in a cold cathode-type vacuum gauge arrangement. The portable magnetic assembly is provided with a connector which engages the external high voltage terminal for providing power to the anode within in the gauge tube. Measurement is made in the same manner as the prior cold cathode gauges in that the current through the anode to the cathode is measured as an indication of the pressure. By providing the portable magnetic assembly, a considerable savings in cost, installation, and maintenance of vacuum gauges for pressure measurement in a gas centrifuge cascade is realizable.

  5. D-Zero Vacuum System

    SciTech Connect

    Wintercorn, S.J.; /Fermilab

    1986-04-07

    The system pumping speed was calculated by taking the reciprocal of the sum of the reciprocal pump speed and the reciprocal line conductances. The conductances of the pipe were calculated from the following formulas taken from the Varian vacuum manual. This report updates the original to reflect the pumping curves and basic vacuum system characteristics for the purchased components and installed piping of the D-Zero vacuum system. The system consists of two Edward's E2M275 two stage mechanical pumps, a Leybold-Heraeus WSU2000 Blower and three Varian 4' diffusion pumps (one for each cryostat). Individual pump and system pumping speed curves and a diagram of the system is included.

  6. SNS Vacuum Instrumentation and Control System

    SciTech Connect

    J. Y. Tang; L. A. Smart; H. C. Hseuh; P. S. Marroquin; L. R. Dalesio; S. A. Lewis; C. A. Lionberger; K. Kishiyama; D. P. Gurd; M. Hechler; W. Schneider

    2001-11-01

    The Spallation Neutron Source (SNS) vacuum instrumentation and control systems are being designed at Lawrence Berkeley National Laboratory (LBNL), Brookhaven National Laboratory (BNL), Thomas Jefferson National Accelerator facility (TJNAF) and Los Alamos National Laboratory (LANL). Each participating lab is responsible for a different section of the machine: LBNL for the Front-End section, LANL for the warm LINAC section, TJNAF for the cold LINAC section and BNL for the Ring and transfer line sections. The vacuum instrumentation and control systems are scheduled to be installed and be in operation at Oak Ridge National Laboratory in 2004 or 2005. Although the requirements vary for different sections of the machine, a collaborative effort has been made to standardize vacuum instrumentation components and the global control system interfaces. This paper summarizes the design of each sub-section of vacuum instrumentation and control system and discusses SNS standards for Ion Pump and Gauge controllers, Programmable Logic Controller (PLC) interfaces, Ladder Logic programming and the SNS global control system interfaces.

  7. A new concept of a vacuum insulation tandem accelerator.

    PubMed

    Sorokin, I; Taskaev, S

    2015-12-01

    A tandem accelerator with vacuum insulation has been proposed and developed in the Budker Institute of Nuclear Physics. Negative hydrogen ions are accelerated by the positive 1 MV potential of the high voltage electrode, converted into protons in the gas stripping target inside the electrode, and then the protons are accelerated again by the same potential. The potential for high voltage and intermediate electrodes is supplied by the sectioned rectifier through a sectioned bushing insulator with a resistive divider. In this work, we propose a radical improvement of the accelerator concept. It is proposed to abandon the separate placement of the accelerator and the power supply and connect them through the bushing insulator. The source of high voltage is proposed to be located inside the accelerator insulator with high voltage and intermediate electrodes mounted on it. This will reduce the facility height from 7 m to 3m and make it really compact and attractive for placing in a clinic. This will significantly increase the stability of the accelerator because the potential for intermediate electrodes can be fed directly from the relevant sections of the rectifier. PMID:26122976

  8. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    SciTech Connect

    William S. McPhee

    1999-05-31

    The objective of this project is to improve the productivity and lower the expense of existing vacuum blasting technology. This technology is used to remove radioactive contamination, PCBs, and lead-based paint and provides worker protection by continuously recycling the material and dust for the decontamination tasks. The proposed work would increase the cleaning rate and provide safe and cost-effective decontamination of the DOE sites. This work focuses on redesigning and improving existing vacuum blasting technology including blast head nozzles, ergonomic handling of the blast head by reducing its weight; brush-ring design, vacuum level regulator, efficiency of the dust separator, and operational control sensors. The redesign is expected to enhance the productivity and economy of the vacuum blasting system by at least 50% over current vacuum blasting systems. There are three phases in the project. Phase I consists of developing and testing mathematical models. Phase II consists of pre-prototype design and fabrication and pre-prototype unit testing. Phase III consists of prototype design and field verification testing. In phase I, mathematical models are developed and analyzed for the nozzle, blast head, wind curtain, and dust separator, first as individual devices and then combined as an integrated model. This allows study of respective airflow and design parameters. The Contractor shall, based on the results of the mathematical modeling studies, design experimental models of the components and test these models. In addition, the Contractor shall develop sensors to detect the relationship of the blast head to the blast surfaces and controls to minimize the dependency on an operator's skill and judgment to obtain optimum positioning, as well as real-time characterization sensors to determine as the blast head is moving the depth to which coatings must be removed, thereby improving production and minimizing waste. In phase II, the Contractor shall design and

  9. Design of the EBIS vacuum system

    SciTech Connect

    Mapes, M.; Smart, L.; Weiss, D.

    2011-03-28

    At Brookhaven National Laboratory the Electron Beam Ion Source (EBIS) is presently being commissioned. The EBIS will be a new heavy ion pre-injector for the Relativistic Heavy Ion Collider (RHIC). The new preinjector has the potential for significant future intensity increases and can produce heavy ion beams of all species including uranium. The background pressure in the ionization region of the EBIS required to be low enough that it does not produce a significant number of ions from background gas. The pressure in the regions of the electron gun and electron collector can be higher than in the ionization region provided there is efficient vacuum separation between the sections. For injection the ions must be accelerated to 100KV by pulsing the EBIS platform. All associated equipment including the vacuum equipment on the platform is at a 100KV potential. The vacuum system design and the vacuum controls for the EBIS platform and transport system will be presented as well as the interface with the Booster Ring which has a pressure 10-11 Torr.

  10. Drift mechanism of laser-induced electron acceleration in vacuum

    NASA Astrophysics Data System (ADS)

    Morgovsky, L.

    2015-12-01

    Laser-induced electron acceleration in vacuum is possible due to the ejection of electrons from the beam as a consequence of the transverse drift orthogonal to the propagation direction. The transverse drift is derived from the general solution of the equations of motion of the electrons in the field of a plane electromagnetic wave with arbitrary polarization. It is shown that the energy gain is proportional to the square of the field strength additionally modulated by the function of the injection and ejection phases. In particular, for a linearly polarized beam this function is reduced to the squared difference between the cosines of these phases. The finite laser pulse duration restricts the range of the field strength suitable for direct electron acceleration in vacuum within certain limits. It is demonstrated that the high efficiency of energy transfer from the laser wave into the kinetic energy of the accelerated electrons demands phase matching between the electron quiver phase at the exit point and the phase of the energy transfer.

  11. Vacuum electron acceleration by using two variable frequency laser pulses

    SciTech Connect

    Saberi, H.; Maraghechi, B.

    2013-12-15

    A method is proposed for producing a relativistic electron bunch in vacuum via direct acceleration by using two frequency-chirped laser pulses. We consider the linearly polarized frequency-chiped Hermit-Gaussian 0, 0 mode lasers with linear chirp in which the local frequency varies linearly in time and space. Electron motion is investigated through a numerical simulation using a three-dimensional particle trajectory code in which the relativistic Newton's equations of motion with corresponding Lorentz force are solved. Two oblique laser pulses with proper chirp parameters and propagation angles are used for the electron acceleration along the z-axis. In this way, an electron initially at rest located at the origin could achieve high energy, γ=319 with the scattering angle of 1.02{sup ∘} with respect to the z-axis. Moreover, the acceleration of an electron in different initial positions on each coordinate axis is investigated. It was found that this mechanism has the capability of producing high energy electron microbunches with low scattering angles. The energy gain of an electron initially located at some regions on each axis could be greatly enhanced compared to the single pulse acceleration. Furthermore, the scattering angle will be lowered compared to the acceleration by using laser pulses propagating along the z-axis.

  12. Accelerator system and method of accelerating particles

    NASA Technical Reports Server (NTRS)

    Wirz, Richard E. (Inventor)

    2010-01-01

    An accelerator system and method that utilize dust as the primary mass flux for generating thrust are provided. The accelerator system can include an accelerator capable of operating in a self-neutralizing mode and having a discharge chamber and at least one ionizer capable of charging dust particles. The system can also include a dust particle feeder that is capable of introducing the dust particles into the accelerator. By applying a pulsed positive and negative charge voltage to the accelerator, the charged dust particles can be accelerated thereby generating thrust and neutralizing the accelerator system.

  13. Vacuum Plasma Spray Forming of Tungsten Lorentz Force Accelerator Components

    NASA Technical Reports Server (NTRS)

    Zimmerman, Frank R.

    2001-01-01

    The Vacuum Plasma Spray (VPS) Laboratory at NASA's Marshall Space Flight Center has developed and demonstrated a fabrication technique using the VPS process to form anode sections for a Lorentz force accelerator from tungsten. Lorentz force accelerators are an attractive form of electric propulsion that provides continuous, high-efficiency propulsion at useful power levels for such applications as orbit transfers or deep space missions. The VPS process is used to deposit refractory metals such as tungsten onto a graphite mandrel of the desired shape. Because tungsten is reactive at high temperatures, it is thermally sprayed in an inert environment where the plasma gun melts and accelerates the metal powder onto the mandrel. A three-axis robot inside the chamber controls the motion of the plasma spray torch. A graphite mandrel acts as a male mold, forming the required contour and dimensions of the inside surface of the anode. This paper describes the processing techniques, design considerations, and process development associated with the VPS forming of the Lorentz force accelerator.

  14. Vacuum Plasma Spray Forming of Tungsten Lorentz Force Accelerator Components

    NASA Technical Reports Server (NTRS)

    Zimmerman, Frank R.

    2004-01-01

    The Vacuum Plasma Spray (VPS) Laboratory at NASA's Marshall Space Flight Center, working with the Jet Propulsion Laboratory, has developed and demonstrated a fabrication technique using the VPS process to form anode and cathode sections for a Lorentz force accelerator made from tungsten. Lorentz force accelerators are an attractive form of electric propulsion that provides continuous, high-efficiency propulsion at useful power levels for such applications as orbit transfers or deep space missions. The VPS process is used to deposit refractory metals such as tungsten onto a graphite mandrel of the desired shape. Because tungsten is reactive at high temperatures, it is thermally sprayed in an inert environment where the plasma gun melts and deposits the molten metal powder onto a mandrel. A three-axis robot inside the chamber controls the motion of the plasma spray torch. A graphite mandrel acts as a male mold, forming the required contour and dimensions for the inside surface of the anode or cathode of the accelerator. This paper describes the processing techniques, design considerations, and process development associated with the VPS forming of Lorentz force accelerator components.

  15. 14 CFR 25.1433 - Vacuum systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe....

  16. 14 CFR 29.1433 - Vacuum systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Vacuum systems. 29.1433 Section 29.1433... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a... the discharge lines from the vacuum air pump when the delivery temperature of the air becomes...

  17. 14 CFR 25.1433 - Vacuum systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe....

  18. 14 CFR 25.1433 - Vacuum systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe....

  19. 14 CFR 25.1433 - Vacuum systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe....

  20. 14 CFR 25.1433 - Vacuum systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe....

  1. 14 CFR 29.1433 - Vacuum systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Vacuum systems. 29.1433 Section 29.1433... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a... the discharge lines from the vacuum air pump when the delivery temperature of the air becomes...

  2. Particle acceleration in the vacuum gaps in black hole magnetospheres

    NASA Astrophysics Data System (ADS)

    Ptitsyna, K.; Neronov, A.

    2016-08-01

    Aims: We consider particle acceleration in the vacuum gaps in magnetospheres of black holes powered by the Blandford-Znajek mechanism and embedded in the radiatively-inefficient accretion flow (RIAF) environment. In this situation, the gap height is limited by the onset of gamma-gamma pair production on the infrared photons originating in the RIAF. Methods: We numerically calculated the acceleration and propagation of charged particles by taking the detailed structure of the electric and magnetic fields in the gap and in the entire black hole magnetosphere into account, as well as the radiative energy losses and interactions of γ-rays produced by the propagated charged particles with the background radiation field of the RIAF. Results: We show that the presence of the vacuum gap has clear observational signatures. The spectra of emission from gaps embedded in a relatively high-luminosity RIAF are dominated by the inverse Compton emission with a sharp, super-exponential cut-off in the very-high-energy gamma-ray band. The cut-off energy is determined by the properties of the RIAF and is largely independent of the structure of magnetosphere and geometry of the gap. The spectra of the gap residing in low-luminosity RIAFs are dominated by synchrotron or curvature emission with the spectra extending into 1-100 GeV energy range. We also consider the effect of possible acceleration of protons in the gap and find that proton energies could reach the ultra-high-energy cosmic ray (UHECR) range only in extremely low-luminosity RIAFs.

  3. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 6 2012-10-01 2012-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  4. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 6 2014-10-01 2014-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  5. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 6 2011-10-01 2011-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  6. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 6 2013-10-01 2013-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  7. The vacuum system for technological unit development and design

    NASA Astrophysics Data System (ADS)

    Zhukeshov, A. M.; Gabdullina, A. T.; Amrenova, A. U.; Giniyatova, Sh G.; Kaibar, A.; Sundetov, A.; Fermakhan, K.

    2015-11-01

    The paper shows results of development of plasma technological unit on the basis of accelerator of vacuum arc and automated system. During the previous years, the authors investigated the operation of pulsed plasma accelerator and developed unique technologies for hardening of materials. Principles of plasma formation in pulsed plasma accelerator were put into basis of the developed unit. Operation of the pulsed arc accelerator was investigated at different parameters of the charge. The developed vacuum system is designed for production of hi-tech plasma units in high technologies in fields of nanomaterials, mechanical and power engineering and production with high added value. Unlike integrated solutions, the system is a module one to allow its low cost, high reliability and simple maintenance. The problems of use of robots are discussed to modernize the technological process.

  8. Vacuum system operating experience review for fusion applications

    SciTech Connect

    Cadwallader, L.C.

    1994-03-01

    This report presents a review of vacuum system operating experiences from particle accelerator, fusion experiment, space simulation chamber, and other applications. Safety relevant operating experiences and accident information are discussed. Quantitative order-of-magnitude estimates of vacuum system component failure rates and accident initiating event frequencies are presented for use in risk assessment, reliability, and availability studies. Safety concerns with vacuum systems are discussed, including personnel safety, foreign material intrusion, and factors relevant to vacuum systems being the primary confinement boundary for tritium and activated dusts. This information should be useful to fusion system designers and safety analysts, such as the team working on the Engineering Design Activities for the International Thermonuclear Experimental Reactor.

  9. LCLS XTOD Tunnel Vacuum System (XVTS)

    SciTech Connect

    Beale, R; Duffy, P; Kishiyama, K; Mckernan, M; McMahon, D; Lewis, S; Trent, J; Tung, L; Shen, S

    2005-11-04

    The vacuum system of the XVTS (X-Ray Vacuum Transport System) for the LCLS (Linac Coherent Light Source) XTOD (X-ray Transport, Optics and Diagnostics) system has been analyzed and configured by the Lawrence Livermore National Laboratory's NTED (New Technologies Engineering Division) as requested by the SLAC/LCLS program. The system layout, detailed analyses and selection of the vacuum components for the XTOD tunnel section are presented in this preliminary design report. The vacuum system was analyzed and optimized using a coupled gas load balance model of sub-volumes of the components to be evacuated. Also included are the plans for procurement, mechanical integration, and the cost estimates.

  10. Space Acceleration Measurement System

    NASA Technical Reports Server (NTRS)

    1993-01-01

    This training video, presented by the Lewis Research Center's Space Experiments Division, gives a background and detailed instructions for preparing the space acceleration measurement system (SAMS) for use. The SAMS measures, conditions, and records forces of low gravity accelerations, and is used to determine the effect of these forces on various experiments performed in microgravity. Inertial sensors are used to measure positive and negative acceleration over a specified frequency range. The video documents the SAMS' uses in different configurations during shuttle missions.

  11. Vacuum measurements of the K500 cyclotron accelerator chamber

    SciTech Connect

    Mallory, M.L.; Miller, P.S.; Kuchar, J.; Hudson, E.D.

    1986-01-01

    To evaluate the effectiveness of the unique internal cryopumping system, the pressure in the K500 superconducting cyclotron was measured as a function of radius for various gas flow rates emanating from the internal PIG source. For the test, a nude ion gauge with vertical dimension less than 2.3 cm was built and mounted on the internal beam probe. The effect of magnetic field on the ion gauge reading was determined and a method of degaussing the cyclotron was devised. Data from the normal shielded ion gauge located approximately 6 m away from the median plane was correlated with the internal vacuum measurements.

  12. Test stand system for vacuum chambers

    NASA Technical Reports Server (NTRS)

    Newman, D. F. (Inventor)

    1973-01-01

    A test stand system for supporting test items in a vacuum chamber is described. The system consists of a frame adapted to conform to the inside of the vacuum chamber and supporting a central vertical shaft. The shaft rotates on bearings located at each end of the shaft. Several vertically spaced plates which fixed to the vertical shaft may be adjusted for height to support the test equipment as required. The test equipment may be rotated during tests without disturbing the vacuum by a manually actuated drive external to the vacuum chamber.

  13. Vacuum systems for the ILC helical undulator

    SciTech Connect

    Malyshev, O. B.; Scott, D. J.; Bailey, I. R.; Barber, D. P.; Baynham, E.; Bradshaw, T.; Brummitt, A.; Carr, S.; Clarke, J. A.; Cooke, P.; Dainton, J. B.; Ivanyushenkov, Y.; Malysheva, L. I.; Moortgat-Pick, G. A.; Rochford, J.; Department of Physics, University of Liverpool Oxford St. Liverpool L69 7ZE; Cockcroft Institute, Warrington WA4 4AD

    2007-07-15

    The International Linear Collider (ILC) positron source uses a helical undulator to generate polarized photons of {approx}10 MeV at the first harmonic. Unlike many undulators used in synchrotron radiation sources, the ILC helical undulator vacuum chamber will be bombarded by photons, generated by the undulator, with energies mostly below that of the first harmonic. Achieving the vacuum specification of {approx}100 nTorr in a narrow chamber of 4-6 mm inner diameter, with a long length of 100-200 m, makes the design of the vacuum system challenging. This article describes the vacuum specifications and calculations of the flux and energy of photons irradiating the undulator vacuum chamber and considers possible vacuum system design solutions for two cases: cryogenic and room temperature.

  14. Evaluation of CBA first string full cell vacuum system

    SciTech Connect

    Foerster, C.L.; Briggs, J.; Christianson, C.; Stattel, P.

    1983-01-01

    The CBA (Colliding Beam Accelerator, formerly known as ISABELLE) Full Cell Magnet System consisting of six superconducting dipole magnets and two superconducting quadrupole magnets requires two separate vacuum systems. One, known as beam vacuum operates below 3 x 10/sup -11/ Torr and the other, known as insulating vacuum, operates at less than 10/sup -7/ Torr to isolate cryo circuits from atmosphere and from the uhv beam tubes. The uhv bore tube is isolated from the 4.0/sup 0/K magnet by thirty-six (36) layers of superinsulation and insulating vacuum. Heat load measurements on the bore tube have been completed and found to agree with data obtained in smaller controlled experiments. Measurements of helium, accumulated on cryogenic pumped charcoal panels over many weeks, have verified sensitive helium mass spectrometer leak detection methods for vacuum integrity, providing sound design of the welded complex. The Full Cell was assembled and operated under conditions that would exist in the completed machine. Pressures below 2 x 10/sup -11/ Torr beam vacuum requirement and below 2 x 10/sup -7/ Torr insulating vacuum, were routinely achieved during all phases of the Full Cell operation and support systems testing.

  15. Temperature of the Vacuum Accelerated by External Fields

    NASA Astrophysics Data System (ADS)

    Labun, Lance; Rafelski, Johann

    2012-03-01

    Using the result of M"uller et al. [1], we show that in a constant electric field E, the electron fluctuations <ψψ> display a thermal Bose spectrum with temperature T=eE/mπ=a/π. This result contrasts with the Fermi spectrum and Hawking-Unruh temperature THU=a/2π expected from viewing the vacuum fluctuations of the electrons as accelerated [2,3]. We consider the temperature in the electric field as a function of magnetic moment g. We find that the temperature in the electric field arises from the Dirac spinor nature of the electron with g=2 and, setting arbitrarily g=1, we recover the Hawking-Unruh THU=a/2π with a Fermi spectrum. [4pt] [1] B. Muller, W. Greiner, and J. Rafelski, Phys. Lett. A63, 181 (1977).[0pt] [2] L.C.B. Crispino, A. Higuchi, George E.A. Matsas, Rev. Mod. Phys. 80, 787 (2008).[0pt] [3] W.-Y. Pauchy Hwang and S. P. Kim, Phys.Rev. D80, 065004 (2009).

  16. Automatic control system for the COSY-TOF vacuum system

    NASA Astrophysics Data System (ADS)

    Abdel-Bary, M.; Abdel-Samad, S.; Kilian, K.

    2005-02-01

    An automatic control system (ACS) for the vacuum installations of the Time-Of-Flight (TOF) spectrometer at the COoler SYnchrotron (COSY) was developed. SIMATIC S7 software and hardware was used to build the control program and Windows Control Center (WinCC) software was taken to make the human-machine interface. The ACS can work automatically or manually. In both cases there are safety interlocks in order to prevent damage of the accelerator or detector components. The testing was firstly done by using external signals and a simulator in WinCC, then secondly we connected it to a real, small vacuum system. The communication between the SIMATIC S7 hardware and the WinCC, which run in a PC computer, is done by Multi Point Interface (MPI). The ACS is now installed in the COSY-TOF experiment and runs routinely.

  17. Ion beam accelerator system

    NASA Technical Reports Server (NTRS)

    Aston, G. (Inventor)

    1981-01-01

    A system is described that combines geometrical and electrostatic focusing to provide high ion extraction efficiency and good focusing of an accelerated ion beam. The apparatus includes a pair of curved extraction grids with multiple pairs of aligned holes positioned to direct a group of beamlets along converging paths. The extraction grids are closely spaced and maintained at a moderate potential to efficiently extract beamlets of ions and allow them to combine into a single beam. An accelerator electrode device downstream from the extraction grids is at a much lower potential than the grids to accelerate the combined beam. The application of the system to ion implantation is mentioned.

  18. Ion beam accelerator system

    NASA Technical Reports Server (NTRS)

    Aston, Graeme (Inventor)

    1984-01-01

    A system is described that combines geometrical and electrostatic focusing to provide high ion extraction efficiency and good focusing of an accelerated ion beam. The apparatus includes a pair of curved extraction grids (16, 18) with multiple pairs of aligned holes positioned to direct a group of beamlets (20) along converging paths. The extraction grids are closely spaced and maintained at a moderate potential to efficiently extract beamlets of ions and allow them to combine into a single beam (14). An accelerator electrode device (22) downstream from the extraction grids, is at a much lower potential than the grids to accelerate the combined beam.

  19. Microgravity Acceleration Measurement System

    NASA Technical Reports Server (NTRS)

    Foster, William

    2009-01-01

    Microgravity Acceleration Measurement System (MAMS) is an ongoing study of the small forces (vibrations and accelerations) on the ISS that result from the operation of hardware, crew activities, as well as dockings and maneuvering. Results will be used to generalize the types of vibrations affecting vibration-sensitive experiments. Investigators seek to better understand the vibration environment on the space station to enable future research.

  20. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    SciTech Connect

    Dr. M.A. Ebadian

    2000-01-13

    The purpose of the project is to increase the productivity and economics of existing vacuum blasting technology. This technology is used to remove radioactive contamination, PCB's and lead-base paint and provides worker and environmental protection by continuously recycling the blast media and the full containment of the dust generated in the process.

  1. Spontaneous excitation of a circularly accelerated atom coupled to electromagnetic vacuum fluctuations

    SciTech Connect

    Jin, Yao; Hu, Jiawei; Yu, Hongwei

    2014-05-15

    We study, using the formalism proposed by Dalibard, Dupont-Roc and Cohen-Tannoudji, the contributions of the vacuum fluctuation and radiation reaction to the rate of change of the mean atomic energy for a circularly accelerated multilevel atom coupled to vacuum electromagnetic fields in the ultrarelativistic limit. We find that the balance between vacuum fluctuation and radiation reaction is broken, which causes spontaneous excitations of accelerated ground state atoms in vacuum. Unlike for a circularly accelerated atom coupled to vacuum scalar fields, the contribution of radiation reaction is also affected by acceleration, and this term takes the same form as that of a linearly accelerated atom coupled to vacuum electromagnetic fields. For the contribution of vacuum fluctuations, we find that in contrast to the linear acceleration case, terms proportional to the Planckian factor are replaced by those proportional to a non-Planck exponential term, and this indicates that the radiation perceived by a circularly orbiting observer is no longer thermal as is in the linear acceleration case. However, for an ensemble of two-level atoms, an effective temperature can be defined in terms of the atomic transition rates, which is found to be dependent on the transition frequency of the atom. Specifically, we calculate the effective temperature as a function of the transition frequency and find that in contrast to the case of circularly accelerated atoms coupled to the scalar field, the effective temperature in the current case is always larger than the Unruh temperature. -- Highlights: •We study the spontaneous excitation of a circularly accelerated atom. •Contribution of radiation reaction to the excitation is affected by acceleration. •The radiation perceived by a circularly orbiting observer is no longer thermal. •An effective temperature can be defined in terms of atomic transition rates. •Effective temperature is larger than Unruh temperature and frequency-dependent.

  2. Method of correcting eddy current magnetic fields in particle accelerator vacuum chambers

    DOEpatents

    Danby, G.T.; Jackson, J.W.

    1990-03-19

    A method for correcting magnetic field aberrations produced by eddy currents induced in a particle accelerator vacuum chamber housing is provided wherein correction windings are attached to selected positions on the housing and the windings are energized by transformer action from secondary coils, which coils are inductively coupled to the poles of electro-magnets that are powered to confine the charged particle beam within a desired orbit as the charged particles are accelerated through the vacuum chamber by a particle-driving rf field. The power inductively coupled to the secondary coils varies as a function of variations in the power supplied by the particle-accelerating rf field to a beam of particles accelerated through the vacuum chamber, so the current in the energized correction coils is effective to cancel eddy current flux fields that would otherwise be induced in the vacuum chamber by power variations (dB/dt) in the particle beam.

  3. Method of correcting eddy current magnetic fields in particle accelerator vacuum chambers

    DOEpatents

    Danby, Gordon T.; Jackson, John W.

    1991-01-01

    A method for correcting magnetic field aberrations produced by eddy currents induced in a particle accelerator vacuum chamber housing is provided wherein correction windings are attached to selected positions on the housing and the windings are energized by transformer action from secondary coils, which coils are inductively coupled to the poles of electro-magnets that are powered to confine the charged particle beam within a desired orbit as the charged particles are accelerated through the vacuum chamber by a particle-driving rf field. The power inductively coupled to the secondary coils varies as a function of variations in the power supplied by the particle-accelerating rf field to a beam of particles accelerated through the vacuum chamber, so the current in the energized correction coils is effective to cancel eddy current flux fields that would otherwise be induced in the vacuum chamber by power variations in the particle beam.

  4. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    SciTech Connect

    William S. McPhee

    2001-08-31

    The Department of Energy (DOE) needs improved technologies to decontaminate large areas of both concrete and steel surfaces. The technology should have high operational efficiency, minimize exposures to workers, and produce low levels of secondary waste. In order to meet the DOE's needs, an applied research and development project for the improvement of a current decontamination technology, Vacuum Blasting, is proposed. The objective of this project is to improve the productivity and lower the expense of the existing vacuum blasting technology which has been widely used in DOE sites for removing radioactive contamination, PCBs, and lead-based paint. The proposed work would increase the productivity rate and provide safe and cost-effective decontamination of the DOE sites.

  5. APS storage ring vacuum system development

    SciTech Connect

    Niemann, R.C.; Benaroya, R.; Choi, M.; Dortwegt, R.J.; Ferry, R.; Goeppner, G.A.; Gonczy, J.D.; Krieger, C.; Howell, J.; Nielsen, R.W.; Roop, B.; Wehrle, R.B.

    1991-01-01

    The Advanced Photon Source synchrotron radiation facility, under construction at the Argonne National Laboratory, incorporates a large ring for the storage of 7 GeV positrons for the generation of photon beams for the facility's materials research program. The Storage Ring's 1104 m circumference is divided into 40 sectors which contain vacuum, beam transport, control, rf and insertion device systems. The vacuum system will operate at a pressure of 1 nTorr and is fabricated from aluminum. The system includes distributed NeG pumping, photon absorbers with lumped pumping, beam position monitors, vacuum diagnostics and valving. An overview of the vacuum system design and details of selected development program results are presented. 5 refs.

  6. Mass spectrometer vacuum housing and pumping system

    DOEpatents

    Coutts, G.W.; Bushman, J.F.; Alger, T.W.

    1996-07-23

    A vacuum housing and pumping system is described for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof. 7 figs.

  7. Mass spectrometer vacuum housing and pumping system

    DOEpatents

    Coutts, Gerald W.; Bushman, John F.; Alger, Terry W.

    1996-01-01

    A vacuum housing and pumping system for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof.

  8. Quantum electrodynamics vacuum polarization modification of photon acceleration in plasma

    SciTech Connect

    Bu Zhigang; Ji Peiyong

    2010-07-15

    The modification of photon frequency shifting based on taking into account the nonlinear quantum electrodynamics vacuum properties in plasma is studied. Motion equations of a laser field propagating in a plasma are derived from the Heisenberg-Euler Lagrangian density. It is found that besides the classical density perturbation of the plasma electrons, the energy density perturbation of the laser field will induce the frequency shifting via the ponderomotive force of the laser field on the vacuum. In addition it is shown that the electron density will be suppressed, which is attributed to a screening effect on the plasma electrons via the quantum vacuum polarization.

  9. The LACARA Vacuum Laser Accelerator Experiment: Beam Positioning and Alignment in a Strong Magnetic Field

    SciTech Connect

    Shchelkunov, Sergey V.; Marshall, T. C.; Hirshfield, J. L.; Wang, Changbiao; LaPointe, M. A.

    2006-11-27

    LACARA (laser cyclotron auto-resonance accelerator) is a vacuum laser accelerator of electrons that is under construction at the Accelerator Test Facility (ATF), Brookhaven National Laboratory. It is expected that the experiment will be assembled by September 2006; this paper presents progress towards this goal. According to numerical studies, as an electron bunch moves along the LACARA solenoidal magnetic field ({approx}5.2 T, length {approx}1 m), it will be accelerated from 50 to {approx}75 MeV by interacting with a 0.8 TW Gaussian-mode circularly polarized optical pulse provided by the ATF CO2 10.6{mu}m laser system. The LACARA laser transport optics must handle 10 J and be capable of forming a Gaussian beam inside the solenoid with a 1.4 mm waist and a Rayleigh range of 60 cm. The electron optics must transport a bunch having input emittance of 0.015 mm-mrad and 100 {mu}m waist through the magnet. Precision alignment between the electron beam and the solenoid magnetic axis is required, and a method to achieve this is described in detail. Emittance- filtering may be necessary to yield an accelerated bunch having a narrow ({approx}1%) energy-spread.

  10. Wireless Integrated Microelectronic Vacuum Sensor System

    NASA Technical Reports Server (NTRS)

    Krug, Eric; Philpot, Brian; Trott, Aaron; Lawrence, Shaun

    2013-01-01

    NASA Stennis Space Center's (SSC's) large rocket engine test facility requires the use of liquid propellants, including the use of cryogenic fluids like liquid hydrogen as fuel, and liquid oxygen as an oxidizer (gases which have been liquefied at very low temperatures). These fluids require special handling, storage, and transfer technology. The biggest problem associated with transferring cryogenic liquids is product loss due to heat transfer. Vacuum jacketed piping is specifically designed to maintain high thermal efficiency so that cryogenic liquids can be transferred with minimal heat transfer. A vacuum jacketed pipe is essentially two pipes in one. There is an inner carrier pipe, in which the cryogenic liquid is actually transferred, and an outer jacket pipe that supports and seals the vacuum insulation, forming the "vacuum jacket." The integrity of the vacuum jacketed transmission lines that transfer the cryogenic fluid from delivery barges to the test stand must be maintained prior to and during engine testing. To monitor the vacuum in these vacuum jacketed transmission lines, vacuum gauge readings are used. At SSC, vacuum gauge measurements are done on a manual rotation basis with two technicians, each using a handheld instrument. Manual collection of vacuum data is labor intensive and uses valuable personnel time. Additionally, there are times when personnel cannot collect the data in a timely fashion (i.e., when a leak is detected, measurements must be taken more often). Additionally, distribution of this data to all interested parties can be cumbersome. To simplify the vacuum-gauge data collection process, automate the data collection, and decrease the labor costs associated with acquiring these measurements, an automated system that monitors the existing gauges was developed by Invocon, Inc. For this project, Invocon developed a Wireless Integrated Microelectronic Vacuum Sensor System (WIMVSS) that provides the ability to gather vacuum

  11. KEKB accelerator control system

    NASA Astrophysics Data System (ADS)

    Akasaka, Nobumasa; Akiyama, Atsuyoshi; Araki, Sakae; Furukawa, Kazuro; Katoh, Tadahiko; Kawamoto, Takashi; Komada, Ichitaka; Kudo, Kikuo; Naito, Takashi; Nakamura, Tatsuro; Odagiri, Jun-ichi; Ohnishi, Yukiyoshi; Sato, Masayuki; Suetake, Masaaki; Takeda, Shigeru; Takeuchi, Yasunori; Yamamoto, Noboru; Yoshioka, Masakazu; Kikutani, Eji

    2003-02-01

    The KEKB accelerator control system including a control computer system, a timing distribution system, and a safety control system are described. KEKB accelerators were installed in the same tunnel where the TRISTAN accelerator was. There were some constraints due to the reused equipment. The control system is based on Experimental Physics and Industrial Control System (EPICS). In order to reduce the cost and labor for constructing the KEKB control system, as many CAMAC modules as possible are used again. The guiding principles of the KEKB control computer system are as follows: use EPICS as the controls environment, provide a two-language system for developing application programs, use VMEbus as frontend computers as a consequence of EPICS, use standard buses, such as CAMAC, GPIB, VXIbus, ARCNET, RS-232 as field buses and use ergonomic equipment for operators and scientists. On the software side, interpretive Python and SAD languages are used for coding application programs. The purpose of the radiation safety system is to protect personnel from radiation hazards. It consists of an access control system and a beam interlock system. The access control system protects people from strong radiation inside the accelerator tunnel due to an intense beam, by controlling access to the beamline area. On the other hand, the beam interlock system prevents people from radiation exposure by interlocking the beam operation. For the convenience of accelerator operation and access control, the region covered by the safety system is divided into three major access control areas: the KEKB area, the PF-AR area, and the beam-transport (BT) area. The KEKB control system required a new timing system to match a low longitudinal acceptance due to a low-alpha machine. This timing system is based on a frequency divider/multiply technique and a digital delay technique. The RF frequency of the KEKB rings and that of the injector Linac are locked with a common divisor frequency. The common

  12. Cryogenic Insulation System for Soft Vacuum

    NASA Technical Reports Server (NTRS)

    Augustynowicz, S. D.; Fesmire, J. E.

    1999-01-01

    The development of a cryogenic insulation system for operation under soft vacuum is presented in this paper. Conventional insulation materials for cryogenic applications can be divided into three levels of thermal performance, in terms of apparent thermal conductivity [k-value in milliwatt per meter-kelvin (mW/m-K)]. System k-values below 0.1 can be achieved for multilayer insulation operating at a vacuum level below 1 x 10(exp -4) torr. For fiberglass or powder operating below 1 x 10(exp -3) torr, k-values of about 2 are obtained. For foam and other materials at ambient pressure, k-values around 30 are typical. New industry and aerospace applications require a versatile, robust, low-cost thermal insulation with performance in the intermediate range. The target for the new composite insulation system is a k-value below 4.8 mW/m-K (R-30) at a soft vacuum level (from 1 to 10 torr) and boundary temperatures of approximately 77 and 293 kelvin (K). Many combinations of radiation shields, spacers, and composite materials were tested from high vacuum to ambient pressure using cryostat boiloff methods. Significant improvement over conventional systems in the soft vacuum range was demonstrated. The new layered composite insulation system was also shown to provide key benefits for high vacuum applications as well.

  13. Vacuum handling system for powdered samples.

    NASA Technical Reports Server (NTRS)

    Birkebak, R. C.; Cremers, C. J.; Lyons, W. E.

    1971-01-01

    A sample system for handling powdered material under vacuum conditions is described. The system features linear motion of up to 0.25 m and the means for complete isolation of the sample and sample system from external apparatus. The system was designed for the measurement of thermophysical properties of lunar material from Apollo missions under thoroughest possible prevention of contamination.

  14. Glow discharge techniques for conditioning high vacuum systems

    SciTech Connect

    Dylla, H.F.

    1988-03-01

    A review is given of glow discharge techniques which are useful for conditioning vacuum vessels for high vacuum applications. Substantial development of glow discharge techniques has been done for the purpose of in-situ conditioning of the large ultrahigh vacuum systems for particle accelerators and magnetic fusion devices. In these applications the glow discharge treatments remove impurities from vessel surfaces in order to minimize particle-induced desorption coefficients. Cleaning mechanisms involve a mixture of sputtering and ion- (or neutral) induced desorption effects depending on the gas mixture (ArO/sub 2/ vs. H/sub 2/) and excitation method (DC, RF, and ECR). The author will review the methodology of glow discharge conditioning, diagnostic measurements provided by residual gas and surface composition analysis, and applications to vessel conditioning and materials processing. 76 refs., 16 figs.

  15. Suppression of an unwanted flow of charged particles in a tandem accelerator with vacuum insulation

    NASA Astrophysics Data System (ADS)

    Ivanov, A.; Kasatov, D.; Koshkarev, A.; Makarov, A.; Ostreinov, Yu.; Shchudlo, I.; Sorokin, I.; Taskaev, S.

    2016-04-01

    In the construction of a tandem accelerator with vacuum insulation several changes were made. This allowed us to suppress the unwanted flow of charged particles in the accelerator, to improve its high-voltage stability, and to increase the proton beam current from 1.6 mA to 5 mA.

  16. SXLS Phase 2 vacuum system

    SciTech Connect

    Schuchman, J.C.; Chou, T.S.; Halama, H.; Hsieh, H.; Kim, T.; Pjerov, S.; Staicu, F.

    1991-01-01

    Phase 1 of the SXLS (Superconducting X-Ray Lithography Source) is described. It is a room temperature, racetrack-shaped electron storage ring, 8.5 meters in circumference. The Phase 2 design consists of replacing the two room temperature 180{degree} dipole magnets of Phase 1 with superconducting magnets. However, even though superconducting magnets are used, the vacuum chambers within them will operate at room temperature. The chambers are constructed as weldments and are made of INCONEL-625. They are bakeable to 150{degrees}C in-situ and incorporate nine photon beam ports. Each have built-in distributed sputter-ion pumps (DIP), non-evaporable getter (NEG) pumps, beam position monitors, and ion clearing electrodes. R D is underway to optimize the DIP, which much operate at 3.86 Tesla, and to develop a low photo yield coating or treatment for the internal surfaces of the chambers.

  17. Re-circulating linac vacuum system

    SciTech Connect

    Wells, Russell P.; Corlett, John N.; Zholents, Alexander A.

    2003-05-09

    The vacuum system for a proposed 2.5 GeV, 10{Mu}A recirculating linac synchrotron light source [1] is readily achievable with conventional vacuum hardware and established fabrication processes. Some of the difficult technical challenges associated with synchrotron light source storage rings are sidestepped by the relatively low beam current and short beam lifetime requirements of a re-circulating linac. This minimal lifetime requirement leads directly to relatively high limits on the background gas pressure through much of the facility. The 10{Mu}A average beam current produces very little synchrotron radiation induced gas desorption and thus the need for an ante-chamber in the vacuum chamber is eliminated. In the arc bend magnets, and the insertion devices, the vacuum chamber dimensions can be selected to balance the coherent synchrotron radiation and resistive wall wakefield effects, while maintaining the modest limits on the gas pressure and minimal outgassing.

  18. Vapor-barrier Vacuum Isolation System

    NASA Technical Reports Server (NTRS)

    Weinstein, Leonard M. (Inventor); Taminger, Karen M. (Inventor)

    2014-01-01

    A system includes a collimated beam source within a vacuum chamber, a condensable barrier gas, cooling material, a pump, and isolation chambers cooled by the cooling material to condense the barrier gas. Pressure levels of each isolation chamber are substantially greater than in the vacuum chamber. Coaxially-aligned orifices connect a working chamber, the isolation chambers, and the vacuum chamber. The pump evacuates uncondensed barrier gas. The barrier gas blocks entry of atmospheric vapor from the working chamber into the isolation chambers, and undergoes supersonic flow expansion upon entering each isolation chamber. A method includes connecting the isolation chambers to the vacuum chamber, directing vapor to a boundary with the working chamber, and supersonically expanding the vapor as it enters the isolation chambers via the orifices. The vapor condenses in each isolation chamber using the cooling material, and uncondensed vapor is pumped out of the isolation chambers via the pump.

  19. PREFACE: International Symposium on Vacuum Science & Technology and its Application for Accelerators (IVS 2012)

    NASA Astrophysics Data System (ADS)

    Pandit, V. S.; Pal, Gautam

    2012-11-01

    The Indian Vacuum Society (IVS) was established in 1970 to promote vacuum science and technology in academic, industrial and R&D institutions in India. IVS is a member society of the International Union for Vacuum Science, Technique and Applications (IUVSTA). It has organized International and national symposia, short term courses and workshops on different aspects of Vacuum Science and Technology at regular intervals. So far 27 National symposia, 4 International Symposia and 47 courses have been organized at various locations in India. There has been an active participation from R&D establishments, universities and Indian industries during all these events. In view of the current global situation and emerging trends in vacuum technology, the executive committee of the IVS suggested to us that we organize an International Symposium at the Variable Energy Cyclotron Centre, Kolkata from 15-17 February 2012. At the Variable Energy Cyclotron Centre we have a large number of high vacuum systems used in the K130 Cyclotron and K500 Superconducting Cyclotron. Also a large cryogenic system using LHe plant is in operation for cryopanels and a superconducting magnet for K-500 Cyclotron. The main areas covered at the symposium were the production and measurement of vacuums, leak detection, design and development of large vacuum systems, vacuum metallurgy, vacuum materials and the application of high vacuums in cyclotrons, LINACS and other accelerators. This symposium provided an opportunity for interaction between active researchers and technologists and allowed them to review the current situation, report recent experimental results, share the available expertise and consider the future R&D efforts needed in this area. Keeping the industrial significance of vacuum technology in mind, an exhibition of the vacuum related equipment, accessories, products etc by various suppliers and manufactures was organized alongside the symposium. Participation by a large number of exhibitors

  20. 242-A evaporator vacuum condenser system

    SciTech Connect

    Smith, V.A.

    1994-09-28

    This document is written for the 242-A evaporator vacuum condenser system (VCS), describing its purpose and operation within the evaporator. The document establishes the operating parameters specifying pressure, temperature, flow rates, interlock safety features and interfacing sub-systems to support its operation.

  1. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... vacuum brakes shall operate in conjunction with the truck or truck tractor brake pedal. (2) Inspection procedure. (i) Check the trailer vacuum system by coupling trailer(s) to truck or truck tractor and...

  2. Computer design and analysis of vacuum systems

    SciTech Connect

    Santeler, D.J.

    1987-07-01

    A computer program has been developed for an IBM compatible personal computer to assist in the design and analysis of vacuum systems. The program has a selection of 12 major schematics with several thousand minor variants incorporating diffusion, turbomolecular, cryogenic, ion, mechanical, and sorption pumps as well as circular tubes, bends, valves, traps, and purge gas connections. The gas throughput versus the inlet pressure of the pump is presented on a log--log graphical display. The conductance of each series component is sequentially added to the graph to obtain the net system behavior Q/sub (//sub P//sub )/. The component conductances may be calculated either from the inlet area and the transmission probability or from the tube length and the diameter. The gas-flow calculations are valid for orifices, short tubes, and long tubes throughout the entire pressure range from molecular through viscous to choked and nonchoked exit flows. The roughing-pump and high-vacuum-pump characteristic curves are numerically integrated to provide a graphical presentation of the system pumpdown. Outgassing data for different materials is then combined to produce a graph of the net system ''outgassing pressure.'' Computer routines are provided for differentiating a real pumpdown curve for system analysis. The computer program is included with the American Vacuum Society course, ''Advanced Vacuum System Design and Analysis,'' or it may be purchased from Process Applications, Inc.

  3. THE SNS VACUUM CONTROL SYSTEM UPGRADE FOR THE SUPERCONDUCTING LINAC

    SciTech Connect

    Williams, Derrick C

    2009-01-01

    The superconducting linac of the Spallation Neutron Source (SNS) has 23 cryomodules whose vacuum system is monitored and controlled by custom built hardware. The original control hardware was provided by Thomas Jefferson National Accelerator Facility (JLab) and contained a variety of custom boards utilizing integrated circuits to perform logic. The need for control logic changes, a desire to increase maintainability, and a desire to increase flexibility to adapt for the future has led to a Programmable Logic Controller (PLC) based upgrade. This paper provides an overview of the commercial off-the-shelf (COTS) hardware being used in the superconducting vacuum control system. Details of the design and challenges to convert a control system during small windows of maintenance periods without disrupting beam operation will be covered in this paper.

  4. High vacuum portable pumping station suitable for accelerator use

    SciTech Connect

    Stattel, P.; Briggs, J.; DeBoer, W.; Skelton, R.

    1985-01-01

    The need for a Portable Pump Station for Ultra High Vacuum use became apparent when the ''Isabelle'' collider was first being designed. A Portable Pump Station had to be developed which contained the following features: maneuverability, compact size, rugged, self protected against various failures, capable of running unattended, and capable of reaching 10/sup -9/ torr. The Pump Station that was developed and other variations are the subject of this paper. Emphasis will be on the Isabelle and HITL versions. 1 ref., 2 figs., 1 tab.

  5. Applications of vacuum technology to novel accelerator problems

    SciTech Connect

    Garwin, E.L.

    1983-01-01

    Vacuum requirements for electron storage rings are most demanding to fulfill, due to the presence of gas desorption caused by large quantities of synchrotron radiation, the very limited area accessible for pumping ports, the need for 10/sup -9/ torr pressures in the ring, and for pressures a decade lower in the interaction regions. Design features of a wide variety of distributed ion sublimation pumps (DIP) developed at SLAC to meet these requirements are discussed, as well as NEG (non-evaporable getter) pumps tested for use in the Large Electron Positron Collider at CERN. Application of DIP to much higher pressures in electron damping rings for the Stanford Linear Collider are discussed.

  6. 14 CFR 29.1433 - Vacuum systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...) There must be means, in addition to the normal pressure relief, to automatically relieve the pressure in... flammable vapors or fluids must meet the requirements of § 29.1183 if they are in a designated fire zone. (c) Other vacuum air system components in designated fire zones must be at least fire resistant....

  7. 14 CFR 29.1433 - Vacuum systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...) There must be means, in addition to the normal pressure relief, to automatically relieve the pressure in... flammable vapors or fluids must meet the requirements of § 29.1183 if they are in a designated fire zone. (c) Other vacuum air system components in designated fire zones must be at least fire resistant....

  8. 14 CFR 29.1433 - Vacuum systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) There must be means, in addition to the normal pressure relief, to automatically relieve the pressure in... flammable vapors or fluids must meet the requirements of § 29.1183 if they are in a designated fire zone. (c) Other vacuum air system components in designated fire zones must be at least fire resistant....

  9. Laser Acceleration in Vacuum with an Open Iris-Loaded Structure

    SciTech Connect

    Xie, Ming

    1997-07-01

    An open iris-loaded waveguide structure is considered for laser acceleration of highly relativistic particle in vacuum. Complete characterization of eigenmodes are given in analytical form for the structure. In particular acceleration performance of the dominant TM mode is evaluated in detail. Transparent scaling laws are derived, and through which significant advantages over other vacuum laser acceleration schemes are demonstrated. The entire parameter space is searched and it is found that below the laser damage threshold of the structure an acceleration gradient around 1 GV/m can be obtained over a phase slippage length of 10s of cm with TWs laser in the wavelength range from 1 to 10 {micro}m.

  10. Late time cosmic acceleration from vacuum Brans-Dicke theory in 5D

    NASA Astrophysics Data System (ADS)

    Ponce de Leon, J.

    2010-05-01

    We show that the scalar-vacuum Brans-Dicke equations in 5D are equivalent to Brans-Dicke theory in 4D with a self-interacting potential and an effective matter field. The cosmological implication, in the context of FRW models, is that the observed accelerated expansion of the universe comes naturally from the condition that the scalar field is not a ghost, i.e. ω > -3/2. We find an effective matter-dominated 4D universe which shows accelerated expansion if -3/2 < ω < -1. We study the question of whether accelerated expansion can be made compatible with large values of ω, within the framework of a 5D scalar-vacuum Brans-Dicke theory with variable, instead of constant, parameter ω. In this framework, and based on a general class of solutions of the field equations, we demonstrate that accelerated expansion is incompatible with large values of ω.

  11. PREFACE: International Symposium on Vacuum Science & Technology and its Application for Accelerators (IVS 2012)

    NASA Astrophysics Data System (ADS)

    Pandit, V. S.; Pal, Gautam

    2012-11-01

    The Indian Vacuum Society (IVS) was established in 1970 to promote vacuum science and technology in academic, industrial and R&D institutions in India. IVS is a member society of the International Union for Vacuum Science, Technique and Applications (IUVSTA). It has organized International and national symposia, short term courses and workshops on different aspects of Vacuum Science and Technology at regular intervals. So far 27 National symposia, 4 International Symposia and 47 courses have been organized at various locations in India. There has been an active participation from R&D establishments, universities and Indian industries during all these events. In view of the current global situation and emerging trends in vacuum technology, the executive committee of the IVS suggested to us that we organize an International Symposium at the Variable Energy Cyclotron Centre, Kolkata from 15-17 February 2012. At the Variable Energy Cyclotron Centre we have a large number of high vacuum systems used in the K130 Cyclotron and K500 Superconducting Cyclotron. Also a large cryogenic system using LHe plant is in operation for cryopanels and a superconducting magnet for K-500 Cyclotron. The main areas covered at the symposium were the production and measurement of vacuums, leak detection, design and development of large vacuum systems, vacuum metallurgy, vacuum materials and the application of high vacuums in cyclotrons, LINACS and other accelerators. This symposium provided an opportunity for interaction between active researchers and technologists and allowed them to review the current situation, report recent experimental results, share the available expertise and consider the future R&D efforts needed in this area. Keeping the industrial significance of vacuum technology in mind, an exhibition of the vacuum related equipment, accessories, products etc by various suppliers and manufactures was organized alongside the symposium. Participation by a large number of exhibitors

  12. APS storage ring vacuum system performance

    SciTech Connect

    Noonan, J.R.; Gagliano, J.; Goeppner, G.A.

    1997-06-01

    The Advanced Photon Source (APS) storage ring was designed to operated with 7-GeV, 100-mA positron beam with lifetimes > 20 hours. The lifetime is limited by residual gas scattering and Touschek scattering at this time. Photon-stimulated desorption and microwave power in the rf cavities are the main gas loads. Comparison of actual system gas loads and design calculations will be given. In addition, several special features of the storage ring vacuum system will be presented.

  13. RFQ accelerator tuning system

    DOEpatents

    Bolie, V.W.

    1990-07-03

    A cooling system is provided for maintaining a preselected operating temperature in a device, which may be an RFQ accelerator, having a variable heat removal requirement, by circulating a cooling fluid through a cooling system remote from the device. Internal sensors in the device enable an estimated error signal to be generated from parameters which are indicative of the heat removal requirement from the device. Sensors are provided at predetermined locations in the cooling system for outputting operational temperature signals. Analog and digital computers define a control signal functionally related to the temperature signals and the estimated error signal, where the control signal is defined effective to return the device to the preselected operating temperature in a stable manner. The cooling system includes a first heat sink responsive to a first portion of the control signal to remove heat from a major portion of the circulating fluid. A second heat sink is responsive to a second portion of the control signal to remove heat from a minor portion of the circulating fluid. The cooled major and minor portions of the circulating fluid are mixed in response to a mixing portion of the control signal, which is effective to proportion the major and minor portions of the circulating fluid to establish a mixed fluid temperature which is effective to define the preselected operating temperature for the remote device. In an RFQ environment the stable temperature control enables the resonant frequency of the device to be maintained at substantially a predetermined value during transient operations. 3 figs.

  14. RFQ accelerator tuning system

    DOEpatents

    Bolie, Victor W.

    1990-01-01

    A cooling system is provided for maintaining a preselected operating temperature in a device, which may be an RFQ accelerator, having a variable heat removal requirement, by circulating a cooling fluid through a cooling system remote from the device. Internal sensors in the device enable an estimated error signal to be generated from parameters which are indicative of the heat removal requirement from the device. Sensors are provided at predetermined locations in the cooling system for outputting operational temperature signals. Analog and digital computers define a control signal functionally related to the temperature signals and the estimated error signal, where the control signal is defined effective to return the device to the preselected operating temperature in a stable manner. The cooling system includes a first heat sink responsive to a first portion of the control signal to remove heat from a major portion of the circulating fluid. A second heat sink is responsive to a second portion of the control signal to remove heat from a minor portion of the circulating fluid. The cooled major and minor portions of the circulating fluid are mixed in response to a mixing portion of the control signal, which is effective to proportion the major and minor portions of the circulating fluid to establish a mixed fluid temperature which is effective to define the preselected operating temperature for the remote device. In an RFQ environment the stable temperature control enables the resonant frequency of the device to be maintained at substantially a predetermined value during transient operations.

  15. Spontaneous excitation of a circularly accelerated atom coupled with vacuum Dirac field fluctuations

    SciTech Connect

    Chen, Jing; Hu, Jiawei; Yu, Hongwei

    2015-02-15

    We study the spontaneous excitation of a circularly accelerated atom coupled with vacuum Dirac field fluctuations by separately calculating the contribution to the excitation rate of vacuum fluctuations and a cross term which involves both vacuum fluctuations and radiation reaction, and demonstrate that although the spontaneous excitation for the atom in its ground state would occur in vacuum, such atoms in circular motion do not perceive a pure thermal radiation as their counterparts in linear acceleration do since the transition rates of the atom do not contain the Planckian factor characterizing a thermal bath. We also find that the contribution of the cross term that plays the same role as that of radiation reaction in the scalar and electromagnetic fields cases differs for atoms in circular motion from those in linear acceleration. This suggests that the conclusion drawn for atoms coupled with the scalar and electromagnetic fields that the contribution of radiation reaction to the mean rate of change of atomic energy does not vary as the trajectory of the atom changes from linear acceleration to circular motion is not a general trait that applies to the Dirac field where the role of radiation reaction is played by the cross term. - Highlights: • Spontaneous excitation of a circularly accelerated atom is studied. • The atom interacts with the Dirac field through nonlinear coupling. • A cross term involving vacuum fluctuations and radiation reaction contributes. • The atom in circular motion does not perceive pure thermal radiation. • The contribution of the cross term changes as the atomic trajectory varies.

  16. Vacuum laser-driven acceleration by two slits-truncated Bessel beams

    SciTech Connect

    Li, D.; Imasaki, K.

    2005-08-29

    An approach of vacuum acceleration by two laser Bessel beams is presented in this letter. With elaborate arrangement, the two Bessel beams are truncated by a set of special annular slits to form consecutive acceleration field in the electron traveling direction. Therefore, the electron of a certain initial energy can be accelerated in the whole interaction region without experiencing deceleration even though the phase-slippage occurs. Furthermore, the Bessel beam can provide a rather long distance for the effective interaction between the electron and the laser field due to its 'diffraction-free' property, resulting in improvement of the energy exchange.

  17. Laser acceleration in vacuum with an open iris-loaded waveguide

    SciTech Connect

    Xie, Ming

    1997-05-01

    An open iris-loaded waveguide structure is considered for laser acceleration of highly relativistic particle in vacuum. Complete characterization of all eigenmodes are given in analytical form for the structure. In particular the dominant radially polarized TM mode is evaluated in detail for laser acceleration. The entire parameter space is searched and it is found that below the laser damage threshold of the structure an acceleration gradient around 1 GV/m can be obtained over a phase slippage length of 10s of cm with TWs laser in the wavelength range from 1 to 10 {mu}m.

  18. Vacuum-cleaning System for Isolation Chambers

    PubMed Central

    Yale, Charles E.

    1969-01-01

    To encourage the utilization of the isolation chamber as a research tool, the cost of its use should be lowered. Methods and devices must be developed which make more efficient use of the space within the isolator and allow the operator to work more effectively in this confined area. A simple vacuum-cleaning system is described; it consists of a nozzle and flexible hose which connect through the isolator wall to an externally placed waste tank, attached by way of its outlet filter to a source of vacuum. The cylindrical waste tank [48 inches (1.219 m) high and 36 inches (0.914 m) in diameter] was sterilized in a large autoclave. During a 9-month test period, the system was used to remove soiled corncob bedding from a large isolator containing 90 adult monocontaminated rats. During this period, the microbial flora of the isolator was unchanged, and the time required to clean the cages was reduced by 50%. This vacuum-cleaning system is a safe, convenient, and economical means of increasing the efficiency of an isolation chamber. Images PMID:5775913

  19. Inertial Mass Viewed as Reaction of the Vacuum to Accelerated Motion

    NASA Technical Reports Server (NTRS)

    Rueda, Alfonso; Haisch, Bernhard

    1999-01-01

    Preliminary analysis of the momentum flux (or of the Poynting vector) of the classical electromagnetic version of the quantum vacuum consisting of zero-point radiation impinging on accelerated objects as viewed by an inertial observer suggests that the resistance to acceleration attributed to inertia may be a force of opposition originating in the vacuum. This analysis avoids the ad hoc modeling of particle-field interaction dynamics used previously by Haisck Rueda and Puthoff (1994) to derive a similar result. This present approach is not dependent upon what happens at the particle point but on how an external observer assesses the kinematical characteristics of the zero-point radiation impinging on the accelerated object. A relativistic form of the equation of motion results from the present analysis.

  20. 21 CFR 884.5070 - Vacuum abortion system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed...

  1. 21 CFR 884.5070 - Vacuum abortion system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed...

  2. 21 CFR 884.5070 - Vacuum abortion system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed...

  3. 21 CFR 884.5070 - Vacuum abortion system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed...

  4. 21 CFR 884.5070 - Vacuum abortion system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed...

  5. Very-Low-Cost, Rugged Vacuum System

    NASA Technical Reports Server (NTRS)

    Kline-Schoder, Robert; Sorensen, Paul; Passow, Christian; Bilski, Steve

    2013-01-01

    NASA, DoD, DHS, and commercial industry have a need for miniaturized, rugged, low-cost vacuum systems. Recent advances in sensor technology have led to the development of very small mass spectrometer detectors as well as other miniature analytical instruments. However, the vacuum systems to support these sensors remain large, heavy, and power-hungry. To meet this need, a miniaturized vacuum system was created based on a very small, rugged, and inexpensive- to-manufacture molecular drag pump (MDP). The MDP is enabled by the development of a miniature, veryhigh- speed, rugged, low-power, brushless DC motor optimized for wide temperature operation and long life. Such a pump represents an order-of-magnitude reduction in mass, volume, and cost over current, commercially available, state-ofthe- art vacuum pumps. The vacuum system consists of the MDP coupled to a ruggedized rough pump (for terrestrial applications or for planets with substantial atmospheres). The rotor in the MDP consists of a simple smooth cylinder of aluminum spinning at approximately 200,000 RPM inside an outer stator housing. The pump stator comprises a cylindrical aluminum housing with one or more specially designed grooves that serve as flow channels. To minimize the length of the pump, the gas is forced down the flow channels of the outer stator to the base of the pump. The gas is then turned and pulled toward the top through a second set of channels cut into an inner stator housing that surrounds the motor. The compressed gas then flows down channels in the motor housing to the exhaust port of the pump. The exhaust port of the pump is connected to a diaphragm or scroll pump. This pump delivers very high performance in a very small envelope. The design was simplified so that a smaller compression ratio, easier manufacturing process, and enhanced ruggedness can be achieved at the lowest possible cost. The machining of the rotor and stators is very simple compared to that necessary to fabricate TMP

  6. Review of Current Nuclear Vacuum System Technologies

    SciTech Connect

    Carroll, M.; McCracken, J.; Shope, T.

    2003-02-25

    Nearly all industrial operations generate unwanted dust, particulate matter, and/or liquid wastes. Waste dust and particulates can be readily tracked to other work locations, and airborne particulates can be spread through ventilation systems to all locations within a building, and even vented outside the building - a serious concern for processes involving hazardous, radioactive, or nuclear materials. Several varieties of vacuum systems have been proposed and/or are commercially available for clean up of both solid and liquid hazardous and nuclear materials. A review of current technologies highlights both the advantages and disadvantages of the various systems, and demonstrates the need for a system designed to address issues specific to hazardous and nuclear material cleanup. A review of previous and current hazardous/nuclear material cleanup technologies is presented. From simple conventional vacuums modified for use in industrial operations, to systems specifically engineered for such purposes, the advantages and disadvantages are examined in light of the following criteria: minimal worker exposure; minimal secondary waste generation;reduced equipment maintenance and consumable parts; simplicity of design, yet fully compatible with all waste types; and ease of use. The work effort reviews past, existing and proposed technologies in light of such considerations. Accomplishments of selected systems are presented, including identified areas where technological improvements could be suggested.

  7. An automated vacuum gauge calibration system

    SciTech Connect

    Abbott, P.J.; Benner, M.S.

    1998-04-01

    An automated system for calibrating vacuum gauges over the pressure range of 10{sup {minus}6} to 0.1 Pa was designed and constructed at the National Institute of Standards and Technology (NIST) for the Department of Energy (DOE) Primary Standards Laboratory at Sandia National Laboratories (SNL). Calculable pressures are generated by passing a known flow of gas through an orifice of known conductance. The orifice conductance is derived from dimensional measurements and accurate flows are generated using metal capillary leaks. The expanded uncertainty (k = 2) in the generated pressure is estimated to be between 1% and 4% over the calibration range. The design, calibration results. and component uncertainties will be discussed.

  8. Vacuum Ultraviolet Photoionization of Complex Chemical Systems

    NASA Astrophysics Data System (ADS)

    Kostko, Oleg; Bandyopadhyay, Biswajit; Ahmed, Musahid

    2016-05-01

    Tunable vacuum ultraviolet (VUV) radiation coupled to mass spectrometry is applied to the study of complex chemical systems. The identification of novel reactive intermediates and radicals is revealed in flame, pulsed photolysis, and pyrolysis reactors, leading to the elucidation of spectroscopy, reaction mechanisms, and kinetics. Mass-resolved threshold photoelectron photoion coincidence measurements provide unprecedented access to vibrationally resolved spectra of free radicals present in high-temperature reactors. Photoionization measurements in water clusters, nucleic acid base dimers, and their complexes with water provide signatures of proton transfer in hydrogen-bonded and π-stacked systems. Experimental and theoretical methods to track ion-molecule reactions and fragmentation pathways in intermolecular and intramolecular hydrogen-bonded systems in sugars and alcohols are described. Photoionization of laser-ablated molecules, clusters, and their reaction products inform thermodynamics and spectroscopy that are relevant to astrochemistry and catalysis. New directions in coupling VUV radiation to interrogate complex chemical systems are discussed.

  9. Vacuum Ultraviolet Photoionization of Complex Chemical Systems.

    PubMed

    Kostko, Oleg; Bandyopadhyay, Biswajit; Ahmed, Musahid

    2016-05-27

    Tunable vacuum ultraviolet (VUV) radiation coupled to mass spectrometry is applied to the study of complex chemical systems. The identification of novel reactive intermediates and radicals is revealed in flame, pulsed photolysis, and pyrolysis reactors, leading to the elucidation of spectroscopy, reaction mechanisms, and kinetics. Mass-resolved threshold photoelectron photoion coincidence measurements provide unprecedented access to vibrationally resolved spectra of free radicals present in high-temperature reactors. Photoionization measurements in water clusters, nucleic acid base dimers, and their complexes with water provide signatures of proton transfer in hydrogen-bonded and π-stacked systems. Experimental and theoretical methods to track ion-molecule reactions and fragmentation pathways in intermolecular and intramolecular hydrogen-bonded systems in sugars and alcohols are described. Photoionization of laser-ablated molecules, clusters, and their reaction products inform thermodynamics and spectroscopy that are relevant to astrochemistry and catalysis. New directions in coupling VUV radiation to interrogate complex chemical systems are discussed. PMID:26980311

  10. ION ACCELERATION SYSTEM

    DOEpatents

    Luce, J.S.; Martin, J.A.

    1960-02-23

    Well focused, intense ion beams are obtained by providing a multi- apertured source grid in front of an ion source chamber and an accelerating multi- apertured grid closely spaced from and in alignment with the source grid. The longest dimensions of the elongated apertures in the grids are normal to the direction of the magnetic field used with the device. Large ion currents may be withdrawn from the source, since they do not pass through any small focal region between the grids.

  11. Polarization effect of a Gaussian laser pulse on magnetic field influenced electron acceleration in vacuum

    NASA Astrophysics Data System (ADS)

    Ghotra, Harjit Singh; Kant, Niti

    2016-04-01

    Electron acceleration by a laser pulse in the presence of azimuthal magnetic field in vacuum has been analyzed. The azimuthal magnetic field influences the trajectory of an accelerated electron during the laser electron interaction in vacuum. The electron trajectory in the absence and presence of azimuthal magnetic field with a linearly polarized (LP) and circularly polarized (CP) laser pulses is analyzed. Due to the presence of azimuthal magnetic field, a confined trajectory of accelerated electron is observed in the direction of propagation of laser pulse. Resonance between the electron and the laser field occurs at optimum values of magnetic field, electron gains high energy from the laser and gets accelerated in the direction of propagation of laser pulse. The azimuthal magnetic field keeps the electron motion close to the axis parallel to the direction of propagation due to which the electron gains and retains high energy for longer distances. The electron energy gain is relatively higher with a CP laser pulse than that with LP laser pulse. The high energy gain of about 2   GeV is observed with a CP laser pulse of peak intensity 2.74 ×1020   W /cm2 in the presence of azimuthal magnetic field of 534   kG .

  12. High acceleration cable deployment system

    NASA Technical Reports Server (NTRS)

    Canning, T. N.; Barns, C. E.; Murphy, J. P.; Gin, B.; King, R. W. (Inventor)

    1981-01-01

    A deployment system that will safely pay one cable from a ballistic forebody when the forebody is separated from an afterbody (to which the cable is secured and when the separation is marked by high acceleration and velocity) is described.

  13. Cold Vacuum Drying (CVD) Facility Vacuum Purge System Chilled Water System Design Description (SYS 47-4)

    SciTech Connect

    IRWIN, J.J.

    2000-06-13

    This system design description (SDD) addresses the Vacuum Purge System Chilled Water (VPSCHW) system. The discussion that follows is limited to the VPSCHW system and its interfaces with associated systems. The reader's attention is directed to Drawings H-1-82162, Cold Vacuum Drying Facility Process Equipment Skid P&ID Vacuum System, and H-1-82224, Cold Vacuum Drying Facility Mechanical Utilities Process Chilled Water P&ID. Figure 1-1 shows the location and equipment arrangement for the VPSCHW system. The VPSCHW system provides chilled water to the Vacuum Purge System (VPS). The chilled water provides the ability to condense water from the multi-canister overpack (MCO) outlet gases during the MCO vacuum and purge cycles. By condensing water from the MCO purge gas, the VPS can assist in drying the contents of the MCO.

  14. Chirped-Pulse Inverse Free Electron Laser: A Tabletop, High-Gradient Vacuum Laser Accelerator

    SciTech Connect

    Hartemann, F V; Troha, A L; Baldis, H A

    2001-03-05

    The inverse free-electron laser (IFEL) interaction is studied both theoretically and numerically in the case where the drive laser intensity approaches the relativistic regime, and the pulse duration is only a few optical cycles long. We show that by using an ultrashort, ultrahigh-intensity drive laser pulse, the IFEL interaction bandwidth and accelerating gradient are increased considerably, thus yielding large energy gains. Using a chirped pulse and negative dispersion focusing optics allows one to take further advantage of the laser optical bandwidth and produce a chromatic line focus maximizing the gradient. The combination of these novel ideas results in a compact vacuum laser accelerator capable of accelerating picosecond electron bunches with a high gradient (GeV/m) and very low energy spread. A computer code which takes into account the three-dimensional nature of the interaction is currently in development and results are expected this Spring.

  15. Central vacuum system with programmable controller reduces energy costs 40%

    SciTech Connect

    De Silva, R.; Varnes, W.; Gaines, A.

    1985-11-01

    The B.F. Goodrich Company needed a more efficient vacuum source for the pilot plant facilities in Avon Lake, OH where new products and manufacturing procedures are developed and evaluated. Fourteen multi-stage steam jet ejector vacuum systems were installed in one building, since a number of vacuum users could be operating concurrently at different levels in the range of 15 to 150 Torr. Ejectors were normally turned on or off to provide the desired vacuum and to conserve steam. Steam is wasted, however, if all stages are on and the amount of vacuum is regulated by bleeding inert gas into the system. Water can also enter the system by kick back, if steam to the ejectors is abruptly shut off. The jet ejector vacuum systems required a steady supply of high pressure steam day and night, but fluctuating demands could create problems in the quality of vacuum obtained. Steam and maintenance costs were also significant. Goodrich decided to replace most of the steam-operated vacuum units because of the high energy requirements, and concurrently reduce hydrocarbon emissions. A major manufacturer or mechanical vacuum equipment was asked to design a vacuum system that could provide steady vacuum in the range of 10 to 250 Torr. The system had to have sufficient capacity for a number of concurrently operating processes, and handle a wide variety of hydrocarbons. The system, designed to meet these requirements and installed in June 1984, consists of a Roots-type vacuum booster with bypass valves, discharging into an intercondenser. The progammable-controlled vacuum system has reduced energy requirements by approximately 40%, and has helped in minimizing emissions. The projected pay-back for the entire system is 1 1/2 years.

  16. Preventing vacuum leaks in the Continuous Electron Beam Accelerator Facility cavity pair bellows

    SciTech Connect

    Henkel, D.P. ); Doolittle, L.R. )

    1994-09-01

    Occasional vacuum leaks have occurred in bellows assemblies of helium pressure vessels at the Continuous Electron Beam Accelerator Facility. The flanged stainless steel bellows assemblies are used to connect the niobium rf cavity pairs to the surrounding liquid helium pressure vessels. An investigation of the source of these leaks has revealed a through-thickness network of microcracks in the cuff weld zones. The cuff material contained a mixture of soft and very hard elongated intermetallic inclusions that were oriented parallel with the weld fusion line; these inclusions served as crack initiation sites. Surface-exposed inclusions, in contact with a chlorine residue from a postweld machining process, induced crevice corrosion during a year of storage. Residual stresses in the weld led to a combination of lamellar tearing and stress corrosion cracking. Propagation of the cracks from one inclusion to another resulted in continuous vacuum leakage paths from the primary (2 K) helium circuit to the vacuum insulation space. Additional vacuum leaks were prevented by reconfiguring the weld geometry and avoiding any processing with chlorinated substances.

  17. Preventing vacuum leaks in the Continuous Electron Beam Accelerator Facility cavity pair bellows

    SciTech Connect

    Daniel P. Henkel; Lawrence R. Doolittle

    1994-05-01

    Occasional vacuum leaks have occurred in bellows assemblies of helium pressure vessels at the Continuous Electron Beam Accelerator Facility. The flanged stainless steel bellows assemblies are used to connect the niobium rf cavity pairs to the surrounding liquid helium pressure vessels. An investigation of the source of these leaks has revealed a through-thickness network of microcracks in the cuff weld zones. The cuff material contained a mixture of soft and very hard elongated intermetallic inclusions that were oriented parallel with the weld fusion line; these inclusions served as crack initiation sites. Surface-exposed inclusions, in contact with a chlorine residue from a postweld machining process, induced crevice corrosion during a year of storage. Residual stresses in the weld led to a combination of lamellar tearing and stress corrosion cracking. Propagation of the cracks from one inclusion to another resulted in continuous vacuum leakage paths from the primary (2 K) helium circuit to the vacuum insulation space. Additional vacuum leaks were prevented by reconfiguring the weld geometry and avoiding any processing with chlorinated substances.

  18. Spent nuclear fuel project cold vacuum drying facility vacuum and purge system design description

    SciTech Connect

    IRWIN, J.J.

    1998-11-30

    This document provides the System Design Description (SDD) for the Cold Vacuum Drying Facility (CVDF) Vacuum and Purge System (VPS) . The SDD was developed in conjunction with HNF-SD-SNF-SAR-O02, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of Processing Systems (Garvin 1998), The HNF-SD-SNF-DRD-002, 1998, Cold Vacuum Drying Facility Design Requirements, and the CVDF Design Summary Report. The SDD contains general descriptions of the VPS equipment, the system functions, requirements and interfaces. The SDD provides references for design and fabrication details, operation sequences and maintenance. This SDD has been developed for the SNFP Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved.

  19. Vacuum system for superconducting LINAC at TIFR

    NASA Astrophysics Data System (ADS)

    Pillay, R. G.

    2008-05-01

    The superconducting heavy ion LINAC booster at the TIFR-BARC facility has been operational. Seven super conducting cryostats containing 4 quarter wave resonators each along with beam lines, bending magnets, switching magnet, diagnostics and vacuum system have been commissioned. The heart of the cryogenic system for the heavy ion superconducting LINAC booster is a custom-built liquid helium refrigerator made by Linde Kryotechnik, Switzerland. The Refrigerator is rated for 300 Watts at 4.5 K with a dual JT (Joule-Thomson valve) at the final cooling stage, which allows simultaneous connections to the cryogenic loads (the LINAC module cryostats) and to a liquid helium storage dewar (1000 litres). The two-phase helium at 4.5 K produced at the JT stage in the refrigerator is delivered to the cryostats through a cryogenic distribution system. The cryogenic distribution system for the LINAC is designed to deliver both liquid helium and liquid nitrogen to the cryostats. The details of UHV system, indigenously developed beam line components, pumps and module cryostats will be presented.

  20. Control systems for Coline accelerators

    NASA Astrophysics Data System (ADS)

    Baczewski, Artur; Latała, Agata; Ceglińska, Kaja; Andrasiak, Michał

    2008-01-01

    Medical linear accelerators are the largest group of devices for therapy of cancer diseases because of their compact design, relatively low operating costs, advanced features and broad range of treatment procedures. Their reliability and ease of operation are very important but the most crucial is to ensure personnel and patient safety. For this reason the development of control and safety systems is the current "leading edge" in medical linear accelerators technology. Provided internal monitoring, machine control and steering, interlock system as well as the automatic recording of the device and patient parameters are nowadays fully controlled by the computer. This paper describes in details projects connected to advanced development of Coline accelerators. As it is crucial to assure reliable steering and monitoring of all the machine settings and actual dose delivered to the patient, advanced control systems composed of steering, control and interlock systems, communication protocol as well as data management system have been developed.

  1. Design and Simulation of a Rotating Aperture & Vacuum System for Neutron Imaging

    SciTech Connect

    Fitsos, P; Hall, J; Rusnak, B; Shen, S

    2006-02-27

    The development of a high-energy (10Mev) neutron imaging system at Lawrence Livermore National Laboratory (LLNL) depends on a precision engineered rotating aperture and vacuum system for generating neutrons that are used for imaging dense objects. This subsystem is part of a larger system which includes a linear accelerator that creates a deuteron beam, a scintillator detector, imaging optics and a high resolution CCD camera. The rotating aperture vacuum system has been successfully simulated and tested. Results show the feasibility of the design and point toward ways to improve the design by minimizing the rotating aperture gap.

  2. A variable acceleration calibration system

    NASA Astrophysics Data System (ADS)

    Johnson, Thomas H.

    2011-12-01

    A variable acceleration calibration system that applies loads using gravitational and centripetal acceleration serves as an alternative, efficient and cost effective method for calibrating internal wind tunnel force balances. Two proof-of-concept variable acceleration calibration systems are designed, fabricated and tested. The NASA UT-36 force balance served as the test balance for the calibration experiments. The variable acceleration calibration systems are shown to be capable of performing three component calibration experiments with an approximate applied load error on the order of 1% of the full scale calibration loads. Sources of error are indentified using experimental design methods and a propagation of uncertainty analysis. Three types of uncertainty are indentified for the systems and are attributed to prediction error, calibration error and pure error. Angular velocity uncertainty is shown to be the largest indentified source of prediction error. The calibration uncertainties using a production variable acceleration based system are shown to be potentially equivalent to current methods. The production quality system can be realized using lighter materials and a more precise instrumentation. Further research is needed to account for balance deflection, forcing effects due to vibration, and large tare loads. A gyroscope measurement technique is shown to be capable of resolving the balance deflection angle calculation. Long term research objectives include a demonstration of a six degree of freedom calibration, and a large capacity balance calibration.

  3. Vacuum electron acceleration driven by a tightly focused radially polarized Gaussian beam.

    PubMed

    Dai, Lin; Li, Jian-Xing; Zang, Wei-Ping; Tian, Jian-Guo

    2011-05-01

    Electron acceleration in vacuum driven by a tightly focused radially polarized Gaussian beam has been studied in detail. Weniger transformation method is used to eliminate the divergence of the radially polarized electromagnetic field derived from the Lax series approach. And, electron dynamics in an intense radially polarized Gaussian beam is analyzed by using the Weniger transformation field. The roles of the initial phase of the electromagnetic field and the injection angle, position and energy of electron in energy gain of electron have been studied in detail. PMID:21643185

  4. DESIGN AND DEVELOPMENT OF THE SNS RING VACUUM INSTRUMENTATION AND CONTROL SYSTEMS.

    SciTech Connect

    HSEUH,H.C.; SMART,L.A.; TANG,J.Y.

    2001-06-18

    BNL is undertaking the design, construction and commissioning of the Spallation Neutron Source (SNS) accumulator ring and the beam transport lines [l]. Ultrahigh vacuum of 10{sup {minus}9} Torr is required in the accumulator ring to minimize beam-gas ionization, a contributing factor to the e-p instability observed in a few high-intensity proton storage rings. All vacuum instrumentation must be capable of local and remote operation to achieve a reliable vacuum system, especially in this extremely high intensity accelerator. The design and development of the SNS ring vacuum instrumentation and control through the Experimental Physics and Industrial Control System (EPICS) distributed real-time software tools are presented.

  5. Direct acceleration of an electron in infinite vacuum by a pulsed radially-polarized laser beam.

    PubMed

    Wong, Liang Jie; Kärtner, Franz X

    2010-11-22

    We study the direct acceleration of a free electron in infinite vacuum along the axis of a pulsed radially-polarized laser beam. We find that net energy transfer from laser pulse to electron is maximized with the tightest focusing. We show that the net energy gain of an electron initially moving at a relativistic velocity may exceed more than half the theoretical limit of energy transfer, which is not possible with an initially stationary electron in the parameter space studied. We determine and analyze the power scaling of maximum energy gain, extending our study to include a relatively unexplored regime of low powers and revealing that substantial acceleration is already possible without the use of petawatt peak-power laser technology. PMID:21164849

  6. Vacuum Pump System Optimization Saves Energy at a Dairy Farm

    SciTech Connect

    2001-08-01

    In 1998, S&S Dairy optimized the vacuum pumping system at their dairy farm in Modesto, California. In an effort to reduce energy costs, S&S Dairy evaluated their vacuum pumping system to determine if efficiency gains and energy savings were possible.

  7. Vacuum pumps and systems: A review of current practice

    NASA Technical Reports Server (NTRS)

    Giles, Stuart

    1986-01-01

    A review of the fundamental characteristics of the many types of vacuum pumps and vacuum pumping systems is given. The optimum pumping range, relative cost, performance limitations, maintenance problems, system operating costs and similar subjects are discussed. Experiences from the thin film deposition, chemical processing, material handling, food processing and other industries, as well as space simulation are used to support conclusions and recommendations.

  8. Helium refrigeration systems for super-conducting accelerators

    SciTech Connect

    Ganni, V.

    2015-12-04

    Many of the present day accelerators are based on superconducting technology which requires 4.5-K or 2-K helium refrigeration systems. These systems utilize superconducting radio frequency (SRF) cavities and/or superconducting magnets which are packaged into vacuum vessels known as cryo-modules (CM’s). Many of the present day accelerators are optimized to operate primarily at around 2-K, requiring specialized helium refrigeration systems which are cost intensive to produce and to operate. Some of the cryogenic refrigeration system design considerations for these challenging applications are discussed.

  9. Voltage measurements at the vacuum post-hole convolute of the Z pulsed-power accelerator

    NASA Astrophysics Data System (ADS)

    Waisman, E. M.; McBride, R. D.; Cuneo, M. E.; Wenger, D. F.; Fowler, W. E.; Johnson, W. A.; Basilio, L. I.; Coats, R. S.; Jennings, C. A.; Sinars, D. B.; Vesey, R. A.; Jones, B.; Ampleford, D. J.; Lemke, R. W.; Martin, M. R.; Schrafel, P. C.; Lewis, S. A.; Moore, J. K.; Savage, M. E.; Stygar, W. A.

    2014-12-01

    Presented are voltage measurements taken near the load region on the Z pulsed-power accelerator using an inductive voltage monitor (IVM). Specifically, the IVM was connected to, and thus monitored the voltage at, the bottom level of the accelerator's vacuum double post-hole convolute. Additional voltage and current measurements were taken at the accelerator's vacuum-insulator stack (at a radius of 1.6 m) by using standard D -dot and B -dot probes, respectively. During postprocessing, the measurements taken at the stack were translated to the location of the IVM measurements by using a lossless propagation model of the Z accelerator's magnetically insulated transmission lines (MITLs) and a lumped inductor model of the vacuum post-hole convolute. Across a wide variety of experiments conducted on the Z accelerator, the voltage histories obtained from the IVM and the lossless propagation technique agree well in overall shape and magnitude. However, large-amplitude, high-frequency oscillations are more pronounced in the IVM records. It is unclear whether these larger oscillations represent true voltage oscillations at the convolute or if they are due to noise pickup and/or transit-time effects and other resonant modes in the IVM. Results using a transit-time-correction technique and Fourier analysis support the latter. Regardless of which interpretation is correct, both true voltage oscillations and the excitement of resonant modes could be the result of transient electrical breakdowns in the post-hole convolute, though more information is required to determine definitively if such breakdowns occurred. Despite the larger oscillations in the IVM records, the general agreement found between the lossless propagation results and the results of the IVM shows that large voltages are transmitted efficiently through the MITLs on Z . These results are complementary to previous studies [R. D. McBride et al., Phys. Rev. ST Accel. Beams 13, 120401 (2010)] that showed efficient

  10. Vacuum seals design and testing for a linear accelerator of the National Spallation Neutron Source

    SciTech Connect

    Z. Chen; C. Gautier; F. Hemez; N. K. Bultman

    2000-02-01

    Vacuum seals are very important to ensure that the Spallation Neutron Source (SNS) Linac has an optimum vacuum system. The vacuum joints between flanges must have reliable seals to minimize the leak rate and meet vacuum and electrical requirements. In addition, it is desirable to simplify the installation and thereby also simplify the maintenance required. This report summarizes an investigation of the metal vacuum seals that include the metal C-seal, Energized Spring seal, Helcoflex Copper Delta seal, Aluminum Delta seal, delta seal with limiting ring, and the prototype of the copper diamond seals. The report also contains the material certifications, design, finite element analysis, and testing for all of these seals. It is a valuable reference for any vacuum system design. To evaluate the suitability of several types of metal seals for use in the SNS Linac and to determine the torque applied on the bolts, a series of vacuum leak rate tests on the metal seals have been completed at Los Alamos Laboratory. A copper plated flange, using the same type of delta seal that was used for testing with the stainless steel flange, has also been studied and tested. A vacuum seal is desired that requires significantly less loading than a standard ConFlat flange with a copper gasket for the coupling cavity assembly. To save the intersegment space the authors use thinner flanges in the design. The leak rate of the thin ConFlat flange with a copper gasket is a baseline for the vacuum test on all seals and thin flanges. A finite element analysis of a long coupling cavity flange with a copper delta seal has been performed in order to confirm the design of the long coupling cavity flange and the welded area of a cavity body with the flange. This analysis is also necessary to predict a potential deformation of the cavity under the combined force of atmospheric pressure and the seating load of the seal. Modeling of this assembly has been achieved using both HKS/Abaqus and COSMOS

  11. Apollo telescope mount thermal systems unit thermal vacuum test

    NASA Technical Reports Server (NTRS)

    Trucks, H. F.; Hueter, U.; Wise, J. H.; Bachtel, F. D.

    1971-01-01

    The Apollo Telescope Mount's thermal systems unit was utilized to conduct a full-scale thermal vacuum test to verify the thermal design and the analytical techniques used to develop the thermal mathematical models. Thermal vacuum test philosophy, test objectives configuration, test monitoring, environment simulation, vehicle test performance, and data correlation are discussed. Emphasis is placed on planning and execution of the thermal vacuum test with particular attention on problems encountered in conducting a test of this maguitude.

  12. Obtaining a proton beam with 5-mA current in a tandem accelerator with vacuum insulation

    NASA Astrophysics Data System (ADS)

    Ivanov, A. A.; Kasatov, D. A.; Koshkarev, A. M.; Makarov, A. N.; Ostreinov, Yu. M.; Sorokin, I. N.; Taskaev, S. Yu.; Shchudlo, I. M.

    2016-06-01

    Suppression of parasitic electron flows and positive ions formed in the beam tract of a tandem accelerator with vacuum insulation allowed a more than threefold increase (from 1.6 to 5 mA) in the current of accelerated 2-MeV protons. Details of the modification are described. Results of experimental investigation of the suppression of secondary charged particles and data on the characteristics of accelerated proton beam with increased current are presented.

  13. Sensitiveness of axial magnetic field on electron acceleration by a radially polarized laser pulse in vacuum

    NASA Astrophysics Data System (ADS)

    Ghotra, Harjit Singh; Kant, Niti

    2015-12-01

    We examine the electron acceleration by a radially polarized (RP) laser pulse in vacuum under influence of an intense axial magnetic field. The electron while interaction with a RP laser pulse gets accelerated with high energy gain. The attained energy gain further enhanced up-to the order of GeV with an intense RP laser pulse. We observe a significant enhancement in energy gain in the presence of an intense axial magnetic field in the direction of propagation of laser pulse. The presence of axial magnetic field improves the strength of v → × B → force which supports the retaining of betatron resonance for longer durations. This improves the electron acceleration with an enhanced energy gain up to 5.2 GeV. It is noticed that the axial magnetic field is sensitive to electron acceleration, small change in magnetic field leads to enhance electron energy gain significantly. Our results also show relatively smaller scattering of the electrons in the presence of axial magnetic field.

  14. Analysis of RFQ vacuum system for HINS tests at MDB

    SciTech Connect

    Piekarz, Henryk; /Fermilab

    2009-07-01

    The arrangement of RFQ vacuum system is briefly described. The projections of the vacuum level using standard out-gassing rates for the RFQ major components are compared with measurements. The permeation of water through the Viton O-rings of the LCW manifold inside the RFQ vacuum vessel is analyzed and compared with RGA data. A model where the out-gassing water from the vanes inner surfaces affects seriously RFQ operation is devised and compared with RFQ performance. The rate of a hydrogen gas spill from the LEBT into the RFQ vacuum space is also projected. Suggestions to correct and improve RFQ operation are presented.

  15. A device for recharging evaporation sources in ultrahigh vacuum systems

    NASA Astrophysics Data System (ADS)

    Fuenzalida, V. M.; Grahmann, C. R.; Herrera, C.

    1998-08-01

    We describe a device capable of recharging the evaporation sources of ultrahigh vacuum systems without breaking the vacuum. The device is operated through the same load lock used for the introduction of the substrates and is able to place grains of materials on resistively heated boats.

  16. 14. VIEW OF VACUUM COATING CHAMBER. THE SYSTEM USED TITANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. VIEW OF VACUUM COATING CHAMBER. THE SYSTEM USED TITANIUM VAPORS TO DEPOSIT TITANIUM COATING ONTO URANIUM PARTS UNDER A VACUUM. (1/11/83) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  17. Distributed UHV system for the folded tandem ion accelerator facility at BARC

    NASA Astrophysics Data System (ADS)

    Gupta, S. K.; Agarwal, A.; Singh, S. K.; Basu, A.; P, Sapna; Sarode, S. P.; Singh, V. P.; Subrahmanyam, N. B. V.; Bhatt, J. P.; Pol, S. S.; Raut, P. J.; Ware, S. V.; Singh, P.; Choudhury, R. K.; Kailas, S.

    2008-05-01

    The 6 MV Folded Tandem Ion Accelerator (FOTIA) Facility at the Nuclear Physics Division, BARC is operational and accelerated beams of both light and heavy ions are being used extensively for basic and applied research. An average vacuum of the order of 10-8-10-9 Torr is maintained for maximum beam transmission and minimum beam energy spreads. The FOTIA vacuum system comprises of about 55 meter long, 100 mm diameter beam lines including various diagnostic devices, two accelerating tubes and four narrow vacuum chambers. The cross sections of the vacuum chambers are 14mm × 24mm for 180°, 38mm × 60mm and 19 × 44 mm for the and 70° & 90° bending magnets and Switching chambers respectively. All the beam line components are UHV compatible, fabricated from stainless steel 304L grade material fitted with metal gaskets. The total volume ~5.8 × 105 cm3 and surface area of 4.6 × 104 cm2, interspersed with total 18 pumping stations. The accelerating tubes are subjected to very high voltage gradient, 20.4 kV/cm, which requires a hydrocarbon free and clean vacuum for smooth operation of the accelerator. Vacuum interlocks are provided to various devices for safe operation of the accelerator. Specially designed sputter ion pumps for higher environmental pressure of 8 atmospheres are used to pump the accelerating tubes and the vacuum chamber for the 180° bending magnet. Fast acting valves are provided for isolating main accelerator against accidental air rush from rest of the beam lines. All the vacuum readings are displayed locally and are also available remotely through computer interface to the Control Room. Vacuum system details are described in this paper.

  18. Multi-GeV electron acceleration by a periodic frequency chirped radially polarized laser pulse in vacuum

    NASA Astrophysics Data System (ADS)

    Singh Ghotra, Harjit; Kant, Niti

    2016-06-01

    Linear and periodic effects of frequency chirp on electron acceleration by radially polarized (RP) laser pulse in vacuum have been investigated. A frequency chirp influences the electron dynamics, betatron resonance, and energy gain by electron during interaction with the RP laser pulse and ensures effective electron acceleration with high energy gain (~GeV). The electron energy gain with a periodic frequency chirped laser pulse is about twice as high as with a linear chirp. Our observations reveal electron energy gain of about 10.5 GeV with a periodic chirped RP petawatt laser pulse in vacuum.

  19. Development of a Modified Vacuum Cleaner for Lunar Surface Systems

    NASA Technical Reports Server (NTRS)

    Toon, Katherine P.; Lee, Steve A.; Edgerly, Rachel D.

    2009-01-01

    The National Aeronautics and Space Administration (NASA) mission to expand space exploration will return humans to the Moon with the goal of maintaining a long-term presence. One challenge that NASA will face returning to the Moon is managing the lunar regolith found on the Moon's surface, which will collect on extravehicular activity (EVA) suits and other equipment. Based on the Apollo experience, the issues astronauts encountered with lunar regolith included eye/lung irritation, and various hardware failures (seals, screw threads, electrical connectors and fabric contamination), which were all related to inadequate lunar regolith mitigation. A vacuum cleaner capable of detaching, transferring, and efficiently capturing lunar regolith has been proposed as a method to mitigate the lunar regolith problem in the habitable environment on lunar surface. In order to develop this vacuum, a modified "off-the-shelf" vacuum cleaner has been used to determine detachment efficiency, vacuum requirements, and optimal cleaning techniques to ensure efficient dust removal in habitable lunar surfaces, EVA spacesuits, and air exchange volume. During the initial development of the Lunar Surface System vacuum cleaner, systematic testing was performed with varying flow rates on multiple surfaces (fabrics and metallics), atmospheric (14.7 psia) and reduced pressures (10.2 and 8.3 psia), different vacuum tool attachments, and several vacuum cleaning techniques to determine the performance requirements for the vacuum cleaner. The data recorded during testing was evaluated by calculating percent removal, relative to the retained simulant on the tested surface. In addition, Scanning Electron Microscopy (SEM) imaging was used to determine particle size distribution retained on the surface. The scope of this paper is to explain the initial phase of vacuum cleaner development, including historical Apollo mission data, current state-of-the-art vacuum cleaner technology, and vacuum cleaner

  20. Development of a Modified Vacuum Cleaner for Lunar Surface Systems

    NASA Technical Reports Server (NTRS)

    Toon, Katherine P.; Lee, Steve A.; Edgerly, Rachel D.

    2010-01-01

    The National Aeronautics and Space Administration (NASA) mission to expand space exploration will return humans to the Moon with the goal of maintaining a long-term presence. One challenge that NASA will face returning to the Moon is managing the lunar regolith found on the Moon's surface, which will collect on extravehicular activity (EVA) suits and other equipment. Based on the Apollo experience, the issues astronauts encountered with lunar regolith included eye/lung irritation, and various hardware failures (seals, screw threads, electrical connectors and fabric contamination), which were all related to inadequate lunar regolith mitigation. A vacuum cleaner capable of detaching, transferring, and efficiently capturing lunar regolith has been proposed as a method to mitigate the lunar regolith problem in the habitable environment on lunar surface. In order to develop this vacuum, a modified "off-the-shelf' vacuum cleaner will be used to determine detachment efficiency, vacuum requirements, and optimal cleaning techniques to ensure efficient dust removal in habitable lunar surfaces, EVA spacesuits, and air exchange volume. During the initial development of the Lunar Surface System vacuum cleaner, systematic testing was performed with varying flow rates on multiple surfaces (fabrics and metallics), atmospheric (14.7 psia) and reduced pressures (10.2 and 8.3 psia), different vacuum tool attachments, and several vacuum cleaning techniques in order to determine the performance requirements for the vacuum cleaner. The data recorded during testing was evaluated by calculating particulate removal, relative to the retained simulant on the tested surface. In addition, optical microscopy was used to determine particle size distribution retained on the surface. The scope of this paper is to explain the initial phase of vacuum cleaner development, including historical Apollo mission data, current state-of-the-art vacuum cleaner technology, and vacuum cleaner testing that has

  1. Vacuum system of the cyclotrons in VECC, Kolkata

    SciTech Connect

    Roy, Anindya; Bhole, R.B.; Akhtar, J.; Yadav, R.C.; Pal, Sarbajit; Sarkar, D.; Bhandari, R.K. E-mail: rbb@vecc.gov.in E-mail: yadav@vecc.gov.in E-mail: dsarkar@vecc.gov.in

    2011-07-01

    The vacuum system of the K=130 Room Temperature Cyclotron (RTC) (operational since 1978) has been recently modernized and the same of the K{sub bend}=520 Superconducting Cyclotron (SCC), currently under commissioning, is being deployed for remote monitoring and control. The vacuum system of RTC is designed to achieve and maintain vacuum level of 2 X 10{sup -6} mbar inside 23 m{sup 3} volume of Resonator tank and DEE tank. This has been upgraded by replacing several valves, Freon units, gauges and pumps. The relay based manual control system has been replaced by PLC based automated system. The SCC vacuum system also has an elaborate arrangement comprising of turbo molecular pumping modules with associated isolation valves and characteristic gauges. This paper describes essential elements, typically used to obtain high (1X10{sup -7} mbar) vacuum using rotary pumps, diffusion pumps and cold traps/turbo-molecular pumps and other system components such as valves, gauges and baffles. The supervisory control methodology/scheme of both the vacuum systems, developed in-house using EPICS (Experimental Physics and Industrial Control System), a standard open-source software tool for designing distributed control system, is also elaborated here. (author)

  2. Three stage vacuum system for ultralow temperature installation

    NASA Astrophysics Data System (ADS)

    Das, N. K.; Pradhan, J.; Naser, Md Z. A.; Mandal, B. Ch; Roy, A.; Kumar, P.; Mallik, C.; Bhandari, R. K.

    2012-11-01

    We use a three stage vacuum system for developing a dilution fridge at VECC, Kolkata. We aim at achieving a cooling power of 20μW at 100mK for various experiments especially in the field of condensed matter and nuclear physics. The system is essentially composed of four segments-bath cryostat, vacuum system, dilution insert and 3He circulation circuit. Requirement of vacuum system at different stages are different. The vacuum system for cryostat and for internal vacuum chamber located within the helium bath is a common turbo molecular pump backed by scroll pump as to maintain a vacuum ~10-6mbar. For bringing down the temperature of the helium evaporator, we use a high throughput Roots pump backed by a dry pump. The pumping system for 3He distillation chamber (still) requires a high pumping speed, so a turbo drag pump backed by a scroll pump has been installed. As the fridge use precious 3He gas for operation, the entire system has been made to be absolutely leak proof with respect to the 3He gas.

  3. PEP-II vacuum system pressure profile modeling using EXCEL

    SciTech Connect

    Nordby, M.; Perkins, C.

    1994-06-01

    A generic, adaptable Microsoft EXCEL program to simulate molecular flow in beam line vacuum systems is introduced. Modeling using finite-element approximation of the governing differential equation is discussed, as well as error estimation and program capabilities. The ease of use and flexibility of the spreadsheet-based program is demonstrated. PEP-II vacuum system models are reviewed and compared with analytical models.

  4. Voltage measurements at the vacuum post-hole convolute of the Z pulsed-power accelerator

    SciTech Connect

    Waisman, E. M.; McBride, R. D.; Cuneo, M. E.; Wenger, D. F.; Fowler, W. E.; Johnson, W. A.; Basilio, L. I.; Coats, R. S.; Jennings, C. A.; Sinars, D. B.; Vesey, R. A.; Jones, B.; Ampleford, D. J.; Lemke, R. W.; Martin, M. R.; Schrafel, P. C.; Lewis, S. A.; Moore, J. K.; Savage, M. E.; Stygar, W. A.

    2014-12-08

    Presented are voltage measurements taken near the load region on the Z pulsed-power accelerator using an inductive voltage monitor (IVM). Specifically, the IVM was connected to, and thus monitored the voltage at, the bottom level of the accelerator’s vacuum double post-hole convolute. Additional voltage and current measurements were taken at the accelerator’s vacuum-insulator stack (at a radius of 1.6 m) by using standard D-dot and B-dot probes, respectively. During postprocessing, the measurements taken at the stack were translated to the location of the IVM measurements by using a lossless propagation model of the Z accelerator’s magnetically insulated transmission lines (MITLs) and a lumped inductor model of the vacuum post-hole convolute. Across a wide variety of experiments conducted on the Z accelerator, the voltage histories obtained from the IVM and the lossless propagation technique agree well in overall shape and magnitude. However, large-amplitude, high-frequency oscillations are more pronounced in the IVM records. It is unclear whether these larger oscillations represent true voltage oscillations at the convolute or if they are due to noise pickup and/or transit-time effects and other resonant modes in the IVM. Results using a transit-time-correction technique and Fourier analysis support the latter. Regardless of which interpretation is correct, both true voltage oscillations and the excitement of resonant modes could be the result of transient electrical breakdowns in the post-hole convolute, though more information is required to determine definitively if such breakdowns occurred. Despite the larger oscillations in the IVM records, the general agreement found between the lossless propagation results and the results of the IVM shows that large voltages are transmitted efficiently through the MITLs on Z. These results are complementary to previous studies [R. D. McBride et al., Phys. Rev. ST Accel. Beams 13, 120401 (2010)] that

  5. Voltage measurements at the vacuum post-hole convolute of the Z pulsed-power accelerator

    DOE PAGESBeta

    Waisman, E. M.; McBride, R. D.; Cuneo, M. E.; Wenger, D. F.; Fowler, W. E.; Johnson, W. A.; Basilio, L. I.; Coats, R. S.; Jennings, C. A.; Sinars, D. B.; et al

    2014-12-08

    Presented are voltage measurements taken near the load region on the Z pulsed-power accelerator using an inductive voltage monitor (IVM). Specifically, the IVM was connected to, and thus monitored the voltage at, the bottom level of the accelerator’s vacuum double post-hole convolute. Additional voltage and current measurements were taken at the accelerator’s vacuum-insulator stack (at a radius of 1.6 m) by using standard D-dot and B-dot probes, respectively. During postprocessing, the measurements taken at the stack were translated to the location of the IVM measurements by using a lossless propagation model of the Z accelerator’s magnetically insulated transmission lines (MITLs)more » and a lumped inductor model of the vacuum post-hole convolute. Across a wide variety of experiments conducted on the Z accelerator, the voltage histories obtained from the IVM and the lossless propagation technique agree well in overall shape and magnitude. However, large-amplitude, high-frequency oscillations are more pronounced in the IVM records. It is unclear whether these larger oscillations represent true voltage oscillations at the convolute or if they are due to noise pickup and/or transit-time effects and other resonant modes in the IVM. Results using a transit-time-correction technique and Fourier analysis support the latter. Regardless of which interpretation is correct, both true voltage oscillations and the excitement of resonant modes could be the result of transient electrical breakdowns in the post-hole convolute, though more information is required to determine definitively if such breakdowns occurred. Despite the larger oscillations in the IVM records, the general agreement found between the lossless propagation results and the results of the IVM shows that large voltages are transmitted efficiently through the MITLs on Z. These results are complementary to previous studies [R. D. McBride et al., Phys. Rev. ST Accel. Beams 13, 120401 (2010)] that showed

  6. Mechanism of Calcium Fluoride Acceleration for Vacuum Carbothermic Reduction of Magnesia

    NASA Astrophysics Data System (ADS)

    Jiang, Yun; Liu, Yu-qin; Ma, Hong-wen; Zhou, Wei-gong

    2016-04-01

    The use of a small amount of calcium fluoride as an additive greatly accelerated the reduction of magnesia during the preparation of magnesium from magnesia using the vacuum carbothermic reduction method. At 1573 K (1300 °C), the magnesia reaction rates of the samples with 1, 3, and 5 pct CaF2 were all approximately 26 pct, three times that of free CaF2, and they were arranged in order of the calcium fluoride weight percentages at 1673 K (1400 °C). The residues were analyzed using chemical analysis, XRD, SEM, EDS, and XRF. The possible acceleration mechanism was discussed. Calcium fluoride combined with magnesia and silicon dioxide to form a eutectic that melted as a channel to aid the solid-solid reaction between carbon and magnesia at approximately 1573 K (1300 °C). Calcium fluoride in the molten state offered free calcium ions and fluorine ions. Fluorine ions entered and distorted the magnesia crystal lattice. The structural strength and chemical stability of the magnesia crystal lattice decreased, which facilitated the magnesia reduction by carbon. Calcium ions were employed to generate the calcium and magnesium silicate. The easyly evaporating fluorides, including magnesium fluoride and silicon tetrafluoride, were regarded as the main reason for the loss of fluorine.

  7. Vacuum Chamber for the Measurement System of the Beam Energy

    NASA Astrophysics Data System (ADS)

    Abakumova, E.; Achasov, M.; Dong, HaiYi; Qu, HuaMin; Krasnov, A.; Kosarev, A.; Muchnoi, N.; Pyata, E.; Xiao, Qiong; Mo, XiaoHu; Wang, YiFang; Zhukov, A.

    Vacuum chamber for the beam energy measurement system based on the Compton backscattering method is presented. The main elements of the chamber are GaAs entrance viewport and a copper mirror. The viewport design provides baking out of the vacuum chamber up to 250 °C. To produce the viewport, an original technology based on brazing GaAs plate by lead has been developed. The vacuum chambers were installed at the BEPC-II and VEPP-4 M colliders. After installation the residual gas pressure is about 10-10 Torr.

  8. Highly sensitive vacuum ion pump current measurement system

    DOEpatents

    Hansknecht, John Christopher

    2006-02-21

    A vacuum system comprising: 1) an ion pump; 2) power supply; 3) a high voltage DC--DC converter drawing power from the power supply and powering the vacuum pump; 4) a feedback network comprising an ammeter circuit including an operational amplifier and a series of relay controlled scaling resistors of different resistance for detecting circuit feedback; 5) an optional power block section intermediate the power supply and the high voltage DC--DC converter; and 6) a microprocessor receiving feedback information from the feedback network, controlling which of the scaling resistors should be in the circuit and manipulating data from the feedback network to provide accurate vacuum measurement to an operator.

  9. Proton beam of 2 MeV 1.6 mA on a tandem accelerator with vacuum insulation

    NASA Astrophysics Data System (ADS)

    Kasatov, D.; Kuznetsov, A.; Makarov, A.; Shchudlo, I.; Sorokin, I.; Taskaev, S.

    2014-12-01

    A source of epithermal neutrons based on a tandem accelerator with vacuum insulation for boron neutron capture therapy of malignant tumors was proposed and constructed. Stationary proton beam with 2 MeV energy, 1.6 mA current, 0.1% energy monochromaticity and 0.5% current stability has just been obtained.

  10. Cold Vacuum Drying Instrument Air System Design Description (SYS 12)

    SciTech Connect

    SHAPLEY, B.J.; TRAN, Y.S.

    2000-06-05

    This system design description (SDD) addresses the instrument air (IA) system of the spent nuclear fuel (SNF). This IA system provides instrument quality air to the Cold Vacuum Drying (CVD) Facility. The IA system is a general service system that supports the operation of the heating, ventilation, and air conditioning (HVAC) system, the process equipment skids, and process instruments in the CVD Facility. The following discussion is limited to the compressor, dryer, piping, and valving that provide the IA as shown in Drawings H-1-82222, Cold Vacuum Drying Facility Mechanical Utilities Compressed & Instrument Air P&ID, and H-1.82161, Cold Vacuum Drying Facility Process Equipment Skid P&ID MCO/Cusk Interface. Figure 1-1 shows the physical location of the 1A system in the CVD Facility.

  11. Trends in accelerator control systems

    SciTech Connect

    Crowley-Milling, M.C.

    1984-04-01

    Over the years, we have seen a revolution in control systems that has followed the ever decreasing cost of computer power and memory. It started with the data gathering, when people distrusted the computer to perform control actions correctly, through the stage of using a computer to perform control actions correctly, through the stage of using a computer system to provide a convenient remote look and adjust facility, to the present day, when more and more emphasis is being placed on using a computer system to simulate or model all or parts of the accelerator, feed in the required performance and calling for the computers to set the various parameters and then measure the actual performance, with iteration if necessary. The progress that has been made in the fields of architecture, communications, computers, interface, software design and operator interface is reviewed.

  12. Thermal Vacuum Control Systems Options for Test Facilities

    NASA Technical Reports Server (NTRS)

    Marchetti, John

    2008-01-01

    This presentation suggests several Thermal Vacuum System (TVAC) control design approach methods for TVAC facilities. Over the past several years many aerospace companies have or are currently upgrading their TVAC testing facilities whether it be by upgrading old equipment or purchasing new. In doing so they are updating vacuum pumping and thermal capabilities of their chambers as well as their control systems. Although control systems are sometimes are considered second to the vacuum or thermal system upgrade process, they should not be taken lightly and must be planned and implemented with the equipment it is to control. Also, emphasis should be placed on how the operators will use the system as well as the requirements of "their" customers. Presented will be various successful methods of TVAC control systems from Programmable Logic Controller (PLC) based to personal computer (PC) based control.

  13. Cold Vacuum Drying facility HVAC system design description

    SciTech Connect

    SINGH, G.

    2000-09-22

    This System Design Description (SDD) addresses the HVAC system for the CVDF. The CVDF HVAC system consists of five subsystems: (1) Administration building HVAC system; (2) Process bay recirculation HVAC system; (3) Process bay local exhaust HVAC and process vent system; (4) Process general supply/exhaust HVAC system; and (5) Reference air system. The HVAC and reference air systems interface with the following systems: the fire protection control system, Monitoring and Control System (MCS), electrical power distribution system (including standby power), compressed air system, Chilled Water (CHW) system, drainage system, and other Cold Vacuum Drying (CVD) control systems not addressed in this SDD.

  14. Mobile accelerator neutron radiography system

    NASA Astrophysics Data System (ADS)

    Dance, W. E.; Carollo, S. F.; Bumgardner, H. M.

    1984-10-01

    The use of neutron radiography for the inspection and maintenance of large structures such as aircraft has been delayed by the absence of a mobile system particularly suited to the requirements of field use. This report describes the production, extensive field testing, evaluation and disposition of the first mobile neutron radiography system to satisfy the majority of requirements for field use. The system is based upon the concept of a mobile on-off neutron radiography system based on a sealed-tube ion accelerator as neutron source demonstrated earlier by the Vought Corporation. Primary features of the system are its self-propelled mobility, versatile positioning capability scaled to Army helicopter dimensions, an on-off beam capability, exposure capability measured in minutes, and suitability for AMMRC laboratory and field use. Included in the report are a description of all components of the system, an evaluation of the operation of the system, an evaluation of its radiographic capabilities, a description of installation elements for the AMMRC site, and recommendations for next-generation systems.

  15. Integration Test of the High Voltage Hall Accelerator System Components

    NASA Technical Reports Server (NTRS)

    Kamhawi, Hani; Haag, Thomas; Huang, Wensheng; Pinero, Luis; Peterson, Todd; Dankanich, John

    2013-01-01

    NASA Glenn Research Center is developing a 4 kilowatt-class Hall propulsion system for implementation in NASA science missions. NASA science mission performance analysis was completed using the latest high voltage Hall accelerator (HiVHAc) and Aerojet-Rocketdyne's state-of-the-art BPT-4000 Hall thruster performance curves. Mission analysis results indicated that the HiVHAc thruster out performs the BPT-4000 thruster for all but one of the missions studied. Tests of the HiVHAc system major components were performed. Performance evaluation of the HiVHAc thruster at NASA Glenn's vacuum facility 5 indicated that thruster performance was lower than performance levels attained during tests in vacuum facility 12 due to the lower background pressures attained during vacuum facility 5 tests when compared to vacuum facility 12. Voltage-Current characterization of the HiVHAc thruster in vacuum facility 5 showed that the HiVHAc thruster can operate stably for a wide range of anode flow rates for discharge voltages between 250 and 600 volts. A Colorado Power Electronics enhanced brassboard power processing unit was tested in vacuum for 1,500 hours and the unit demonstrated discharge module efficiency of 96.3% at 3.9 kilowatts and 650 volts. Stand-alone open and closed loop tests of a VACCO TRL 6 xenon flow control module were also performed. An integrated test of the HiVHAc thruster, brassboard power processing unit, and xenon flow control module was performed and confirmed that integrated operation of the HiVHAc system major components. Future plans include continuing the maturation of the HiVHAc system major components and the performance of a single-string integration test.

  16. Introduction to the magnet and vacuum systems of an electron storage ring

    SciTech Connect

    Weng, W.T.

    1982-08-15

    An accelerator or storage ring complex is a concerted interplay of various functional systems. For the convenience of discussion we can divide it into the following systems: injector, magnet, RF, vacuum, instrumentation and control. In addition, the conventional construction of the building and radiation safety consideration are also needed and finally the beam lines, detector, data acquisition and analysis set-ups for research programs. Dr. L. Teng has given a comprehensive review of the whole complex and the operation of such a facility. I concentrate on the description of magnet and vacuum systems. Only the general function of each system and the basic design concepts will be introduced, no detailed engineering practice will be given which will be best done after a machine design is produced. For further understanding and references a table of bibliography is provided at the end of the paper.

  17. Thermal vacuum integrated system test at B-2

    NASA Astrophysics Data System (ADS)

    Kudlac, M. T.; Weaver, H. F.; Cmar, M. D.

    2012-04-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Plum Brook Station (PBS) Space Propulsion Research Facility, commonly referred to as B-2, is NASA's third largest thermal vacuum facility. It is the largest designed to store and transfer large quantities of liquid hydrogen and liquid oxygen, and is perfectly suited to support developmental testing of chemical propulsion systems as well as fully integrated stages. The facility is also capable of providing thermal-vacuum simulation services to support testing of large lightweight structures, Cryogenic Fluid Management (CFM) systems, electric propulsion test programs, and other In-Space propulsion programs. A recently completed integrated system test demonstrated the refurbished thermal vacuum capabilities of the facility. The test used the modernized data acquisition and control system to monitor the facility during pump down of the vacuum chamber, operation of the liquid nitrogen heat sink (or cold wall) and the infrared lamp array. A vacuum level of 1.3 × 10-4 Pa (1 × 10-6 torr) was achieved. The heat sink provided a uniform temperature environment of approximately 77 K (139°R) along the entire inner surface of the vacuum chamber. The recently rebuilt and modernized infrared lamp array produced a nominal heat flux of 1.4 kW/m2 at a chamber diameter of 6.7 m (22 ft) and along 11 m (36 ft) of the chamber's cylindrical vertical interior. With the lamp array and heat sink operating simultaneously, the thermal systems produced a heat flux pattern simulating radiation to space on one surface and solar exposure on the other surface. The data acquired matched pretest predictions and demonstrated system functionality.

  18. Thermal Vacuum Integrated System Test at B-2

    NASA Technical Reports Server (NTRS)

    Kudlac, Maureen T.; Weaver, Harold F.; Cmar, Mark D.

    2012-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Plum Brook Station (PBS) Space Propulsion Research Facility, commonly referred to as B-2, is NASA s third largest thermal vacuum facility. It is the largest designed to store and transfer large quantities of liquid hydrogen and liquid oxygen, and is perfectly suited to support developmental testing of chemical propulsion systems as well as fully integrated stages. The facility is also capable of providing thermal-vacuum simulation services to support testing of large lightweight structures, Cryogenic Fluid Management (CFM) systems, electric propulsion test programs, and other In-Space propulsion programs. A recently completed integrated system test demonstrated the refurbished thermal vacuum capabilities of the facility. The test used the modernized data acquisition and control system to monitor the facility during pump down of the vacuum chamber, operation of the liquid nitrogen heat sink (or cold wall) and the infrared lamp array. A vacuum level of 1.3x10(exp -4)Pa (1x10(exp -6)torr) was achieved. The heat sink provided a uniform temperature environment of approximately 77 K (140deg R) along the entire inner surface of the vacuum chamber. The recently rebuilt and modernized infrared lamp array produced a nominal heat flux of 1.4 kW/sq m at a chamber diameter of 6.7 m (22 ft) and along 11 m (36 ft) of the chamber s cylindrical vertical interior. With the lamp array and heat sink operating simultaneously, the thermal systems produced a heat flux pattern simulating radiation to space on one surface and solar exposure on the other surface. The data acquired matched pretest predictions and demonstrated system functionality.

  19. Cold Vacuum Drying (CVD) Electrical System Design Description

    SciTech Connect

    BRISBIN, S.A.

    1999-06-17

    This document provides a technical explanation of the design and operation of the electrical system for the Cold Vacuum Drying Facility. This document identifies the requirements, and the basis for the requirements and details on how the requirements have been implemented in the design and construction of the facility. This document also provides general guidance for the surveillance, testing, and maintenance of this system.

  20. Microwave-vacuum drying system (MIVAC). Progress report No. 3

    SciTech Connect

    Wear, F C

    1980-01-01

    Progress in developing a microwave vacuum system (MIVAC) for drying grain at a facility capable of handling up to 400 bushels/h and of storing up to 1000 bushels each of wet and dry grain is reported. The design of a prototype 48 kW drying system is described. (LCL)

  1. Semipermanent sealing of leaks in high vacuum systems

    NASA Technical Reports Server (NTRS)

    Christian, J. D.; Gilbreath, W. P.

    1974-01-01

    Silicone-rubber adhesive is applied externally to seal hair-line cracks in sections of high vacuum system while system is partially evacuated. No pretreatment of surface is required since adhesive will be drawn into crack while diffusion or ion pump is off.

  2. 21 CFR 864.9125 - Vacuum-assisted blood collection system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum...

  3. 21 CFR 864.9125 - Vacuum-assisted blood collection system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum...

  4. 21 CFR 864.9125 - Vacuum-assisted blood collection system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum...

  5. 21 CFR 864.9125 - Vacuum-assisted blood collection system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum...

  6. 21 CFR 864.9125 - Vacuum-assisted blood collection system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum...

  7. The Vacuum-Operated Nutrient Delivery System: hydroponics for microgravity.

    PubMed

    Brown, C S; Cox, W M; Dreschel, T W; Chetirkin, P V

    1992-11-01

    A nutrient delivery system that may have applicability for growing plants in microgravity is described. The Vacuum-Operated Nutrient Delivery System (VONDS) draws nutrient solution across roots that are under a partial vacuum at approximately 91 kPa. Bean (Phaseolus vulgaris L. cv. Blue Lake 274) plants grown on the VONDS had consistently greater leaf area and higher root, stem, leaf, and pod dry weights than plants grown under nonvacuum control conditions. This study demonstrates the potential applicability of the VONDS for growing plants in microgravity for space biology experimentation and/or crop production. PMID:11537607

  8. The water outgassing rate of internal surfaces of vacuum systems

    NASA Astrophysics Data System (ADS)

    Rozanov, L. N.

    2016-07-01

    On the basis of experimental adsorption isotherm the ratio between the real and geometrical surfaces was calculated and the amount of gas required to form a monolayer was defined. Simultaneous usage of Henry and Frendlih equations allowed to determine the dependence of the heat of adsorption on the logarithm of the absorbed gas amount A mathematical model of pumping of the vacuum systems with adsorbing walls is presented. This model uses the parameters of the vacuum system and the dependence of the adsorption heat on the amount of the adsorbed gas .The conditions of the existence of regular pumping regime are discussed. The structure database vacuum adsorption properties of materials was proposed. The experimental data on the determination of the adsorption outgassing rate were released.

  9. Experimental system for drilling simulated lunar rock in ultrahigh vacuum

    NASA Technical Reports Server (NTRS)

    Roepke, W. W.

    1975-01-01

    An experimental apparatus designed for studying drillability of hard volcanic rock in a simulated lunar vacuum of 5 x 10 to the minus 10th power torr is described. The engineering techniques used to provide suitable drilling torque inside the ultrahigh vacuum chamber while excluding all hydrocarbon are detailed. Totally unlubricated bearings and gears were used to better approximate the true lunar surface conditions within the ultrahigh vacuum system. The drilling system has a starting torque of 30 in-lb with an unloaded running torque of 4 in-lb. Nominal torque increase during drilling is 4.5 in-lb or a total drilling torque of 8.5 in-lb with a 100-lb load on the drill bit at 210 rpm. The research shows conclusively that it is possible to design operational equipment for moderate loads operating under UHV conditions without the use of sealed bearings or any need of lubricants whatsoever.

  10. Systems and methods for analyzing liquids under vacuum

    DOEpatents

    Yu, Xiao-Ying; Yang, Li; Cowin, James P.; Iedema, Martin J.; Zhu, Zihua

    2013-10-15

    Systems and methods for supporting a liquid against a vacuum pressure in a chamber can enable analysis of the liquid surface using vacuum-based chemical analysis instruments. No electrical or fluid connections are required to pass through the chamber walls. The systems can include a reservoir, a pump, and a liquid flow path. The reservoir contains a liquid-phase sample. The pump drives flow of the sample from the reservoir, through the liquid flow path, and back to the reservoir. The flow of the sample is not substantially driven by a differential between pressures inside and outside of the liquid flow path. An aperture in the liquid flow path exposes a stable portion of the liquid-phase sample to the vacuum pressure within the chamber. The radius, or size, of the aperture is less than or equal to a critical value required to support a meniscus of the liquid-phase sample by surface tension.

  11. Proof-Of-Principle Experiment for Laser-Driven Acceleration of Relativistic Electrons in a Semi-Infinite Vacuum

    SciTech Connect

    Plettner, T.; Byer, R.L.; Colby, E.; Cowan, B.; Sears, C.M.S.; Spencer, J.E.; Siemann, R.H.; /SLAC

    2006-03-01

    We recently achieved the first experimental observation of laser-driven particle acceleration of relativistic electrons from a single Gaussian near-infrared laser beam in a semi-infinite vacuum. This article presents an in-depth account of key aspects of the experiment. An analysis of the transverse and longitudinal forces acting on the electron beam is included. A comparison of the observed data to the acceleration viewed as an inverse transition radiation process is presented. This is followed by a detailed description of the components of the experiment and a discussion of future measurements.

  12. Heavy-ion inertial fusion: influence of target gain on accelerator parameters for vacuum-propagation regimes in reaction chambers

    SciTech Connect

    Mark, J.W.K.; Bangerter, R.O.; Barletta, W.A.; Fawley, W.M.; Judd, D.L.

    1982-03-04

    Target physics imposes requirements on the design of inertial fusion drivers. The influence of beam propagation in near vacuum fusion reaction chambers is evaluated for the relation between target gain and the phase-space requirements of heavy-ion accelerators. Initial results suggest that neutralization of the ion beam has a much greater positive effect than the deleterious one of beam stripping provided that the fusion chamber pressure is < 10/sup -3/ torr (of Li vapor or equivalent).

  13. Connector for vacuum-jacketed lines cuts tubing system cost

    NASA Technical Reports Server (NTRS)

    Calvert, H. F.

    1964-01-01

    A low-cost fitting, fabricated from standard connectors, is used for disconnecting flow lines in cryogenic systems. Utilizing vacuum-jacketed lines made from two sizes of tubing welded at the ends, the connectors are stronger and setup time is reduced.

  14. Analysis of high vacuum systems using SINDA'85

    NASA Technical Reports Server (NTRS)

    Spivey, R. A.; Clanton, S. E.; Moore, J. D.

    1993-01-01

    The theory, algorithms, and test data correlation analysis of a math model developed to predict performance of the Space Station Freedom Vacuum Exhaust System are presented. The theory used to predict the flow characteristics of viscous, transition, and molecular flow is presented in detail. Development of user subroutines which predict the flow characteristics in conjunction with the SINDA'85/FLUINT analysis software are discussed. The resistance-capacitance network approach with application to vacuum system analysis is demonstrated and results from the model are correlated with test data. The model was developed to predict the performance of the Space Station Freedom Vacuum Exhaust System. However, the unique use of the user subroutines developed in this model and written into the SINDA'85/FLUINT thermal analysis model provides a powerful tool that can be used to predict the transient performance of vacuum systems and gas flow in tubes of virtually any geometry. This can be accomplished using a resistance-capacitance (R-C) method very similar to the methods used to perform thermal analyses.

  15. A new vacuum insulated tandem accelerator for detection of explosives and special nuclear materials

    NASA Astrophysics Data System (ADS)

    Farrell, J. Paul; Powell, James; Murzina, Marina; Dudnikov, Vadim; Ivanov, Alexander

    2005-05-01

    This paper describes a radiation source that can be used to actively interrogate containers, trucks, trains, cars, etc to determine the presence and location of chemical explosives and special nuclear materials such as uranium and plutonium. Active interrogation methods using high energy photon or neutron sources to induce fission are the only feasible option for detection of highly enriched uranium (HEU) because passive detection methods are easily compromised by even moderate amounts of shielding. For detection of chemical explosives, the same active interrogation device can be used to produce resonant photons that can detect nitrogen that is used in most chemical explosives. The accelerator based system described here produces a penetrating beam of high energy photons or neutrons that can "see" inside a sealed container. If chemical explosives or special nuclear materials are present, they will emit a characteristic signal that is detected and interpreted by electronic sensors. Shielded "dirty bombs" can be detected by the attenuation of high energy photons caused by the density of the shield material. The interrogating source of radiation is based upon a new high current negative ion source and high current tandem accelerator. The accelerator accelerates ions and projects them onto an appropriately designed target. The target converts the energy of the ion beam into a high energy highly penetrating photon or neutron beam. The beam is made to pass through the container. If explosives, special nuclear materials or shielded dirty bombs are present, the beam together with a suitable detection system uniquely identifies the location, amount and density of material.

  16. Cold Vacuum Drying (CVD) Electrical System Design Description

    SciTech Connect

    SINGH, G.

    2000-05-01

    This system design description (SDD) provides a technical explanation of the design and operation of the electrical system for the Cold Vacuum Drying Facility (CVDF). This SDD also identifies the requirements, and the basis for the requirements and details on how the requirements have been implemented in the design and construction of the facility. This SDD also provides general guidance for the surveillance, testing, and maintenance of this system.

  17. New baking system for the RFX vacuum vessel

    SciTech Connect

    Collarin, P.; Luchetta, A.; Sonato, P.; Toigo, V.; Zaccaria, P.; Zollino, G.

    1996-12-31

    A heating system based on eddy currents has been developed for the vacuum vessel of the RFX Reversed Field Pinch device. After a testing phase, carried out at low power, the final power supply system has been designed and installed. It has been used during last year to bake out the vessel and the graphite first wall up to 320{degree}C. Recently the heating system has been completed with a control system that allows for baking sessions with an automatic control of the vacuum vessel temperature and for pulse sessions with a heated first wall. After the description of the preliminary analyses and tests, and of the main characteristics of the power supply and control systems, the experimental results of the baking sessions performed during last year are presented. 6 refs., 7 figs.

  18. D-Zero Cryogenic System VLPC & Solenoid Vacuum System Instrumentation, Control, and Logic

    SciTech Connect

    Markley, D.; /Fermilab

    1998-01-16

    The DZERO VLPC Cryostat and the Superconducting Solenoid both require an insulating Vacuum of 10{sup -5} Torr or less. There is a vacuum system on the Detector Platform consisting of 2 Turbomolecular vacuum pumps and their associated piping, valves, instrumentation that are dedicated to this task. This vacuum equipment requires an operator interface and control logic in order to function properly. The operator interface allows an operator to monitor, control and configure the proper pumping setup required at any given time. The control logic is needed to protect the Vacumm vessels and Vacuum equipment from catastrophic events that may harm them. This is typically done with interlock chains or strings.

  19. [Double-guided vacuum trephine system "Asmotom"].

    PubMed

    Bull, H; Deutschmann, S; Schlote, H W

    1991-01-01

    A new, doubly guided cornea suction trephine system is presented. By means of a suction rim placed on the limbus corneal and a suction disc in the centre of the cornea the vault of the cornea is preserved throughout the trephination procedure. Cutting is performed by a motor trephine, which rotates between the inner and the outer suction. The system allows creation of an absolutely safe perforation in a 360 degrees cut. The cut edges are precise and sharp. Both donor and recipient are trephined from the epithelial side. The endothelial cell loss is very low, amounting to 0.170 mm. The suction stabilization prevents any tilting of the trephine and avoids elliptical forms. Preliminary clinical experiences are presented. PMID:1757052

  20. RHIC sextant test: Accelerator systems and performance

    SciTech Connect

    Pilat, F.; Trbojevic, D.; Ahrens, L.

    1997-08-01

    One sextant of the RHIC Collider was commissioned in early 1997 with beam. We describe here the performance of the accelerator systems, instrumentation subsystems and application software. We also describe a ramping test without beam that took place after the commissioning with beam. Finally, we analyze the implications of accelerator systems performance and their impact on the planning for RHIC installation and commissioning.

  1. The Spallation Neutron Source accelerator system design

    NASA Astrophysics Data System (ADS)

    Henderson, S.; Abraham, W.; Aleksandrov, A.; Allen, C.; Alonso, J.; Anderson, D.; Arenius, D.; Arthur, T.; Assadi, S.; Ayers, J.; Bach, P.; Badea, V.; Battle, R.; Beebe-Wang, J.; Bergmann, B.; Bernardin, J.; Bhatia, T.; Billen, J.; Birke, T.; Bjorklund, E.; Blaskiewicz, M.; Blind, B.; Blokland, W.; Bookwalter, V.; Borovina, D.; Bowling, S.; Bradley, J.; Brantley, C.; Brennan, J.; Brodowski, J.; Brown, S.; Brown, R.; Bruce, D.; Bultman, N.; Cameron, P.; Campisi, I.; Casagrande, F.; Catalan-Lasheras, N.; Champion, M.; Champion, M.; Chen, Z.; Cheng, D.; Cho, Y.; Christensen, K.; Chu, C.; Cleaves, J.; Connolly, R.; Cote, T.; Cousineau, S.; Crandall, K.; Creel, J.; Crofford, M.; Cull, P.; Cutler, R.; Dabney, R.; Dalesio, L.; Daly, E.; Damm, R.; Danilov, V.; Davino, D.; Davis, K.; Dawson, C.; Day, L.; Deibele, C.; Delayen, J.; DeLong, J.; Demello, A.; DeVan, W.; Digennaro, R.; Dixon, K.; Dodson, G.; Doleans, M.; Doolittle, L.; Doss, J.; Drury, M.; Elliot, T.; Ellis, S.; Error, J.; Fazekas, J.; Fedotov, A.; Feng, P.; Fischer, J.; Fox, W.; Fuja, R.; Funk, W.; Galambos, J.; Ganni, V.; Garnett, R.; Geng, X.; Gentzlinger, R.; Giannella, M.; Gibson, P.; Gillis, R.; Gioia, J.; Gordon, J.; Gough, R.; Greer, J.; Gregory, W.; Gribble, R.; Grice, W.; Gurd, D.; Gurd, P.; Guthrie, A.; Hahn, H.; Hardek, T.; Hardekopf, R.; Harrison, J.; Hatfield, D.; He, P.; Hechler, M.; Heistermann, F.; Helus, S.; Hiatt, T.; Hicks, S.; Hill, J.; Hill, J.; Hoff, L.; Hoff, M.; Hogan, J.; Holding, M.; Holik, P.; Holmes, J.; Holtkamp, N.; Hovater, C.; Howell, M.; Hseuh, H.; Huhn, A.; Hunter, T.; Ilg, T.; Jackson, J.; Jain, A.; Jason, A.; Jeon, D.; Johnson, G.; Jones, A.; Joseph, S.; Justice, A.; Kang, Y.; Kasemir, K.; Keller, R.; Kersevan, R.; Kerstiens, D.; Kesselman, M.; Kim, S.; Kneisel, P.; Kravchuk, L.; Kuneli, T.; Kurennoy, S.; Kustom, R.; Kwon, S.; Ladd, P.; Lambiase, R.; Lee, Y. Y.; Leitner, M.; Leung, K.-N.; Lewis, S.; Liaw, C.; Lionberger, C.; Lo, C. C.; Long, C.; Ludewig, H.; Ludvig, J.; Luft, P.; Lynch, M.; Ma, H.; MacGill, R.; Macha, K.; Madre, B.; Mahler, G.; Mahoney, K.; Maines, J.; Mammosser, J.; Mann, T.; Marneris, I.; Marroquin, P.; Martineau, R.; Matsumoto, K.; McCarthy, M.; McChesney, C.; McGahern, W.; McGehee, P.; Meng, W.; Merz, B.; Meyer, R.; Meyer, R.; Miller, B.; Mitchell, R.; Mize, J.; Monroy, M.; Munro, J.; Murdoch, G.; Musson, J.; Nath, S.; Nelson, R.; Nelson, R.; O`Hara, J.; Olsen, D.; Oren, W.; Oshatz, D.; Owens, T.; Pai, C.; Papaphilippou, I.; Patterson, N.; Patterson, J.; Pearson, C.; Pelaia, T.; Pieck, M.; Piller, C.; Plawski, T.; Plum, M.; Pogge, J.; Power, J.; Powers, T.; Preble, J.; Prokop, M.; Pruyn, J.; Purcell, D.; Rank, J.; Raparia, D.; Ratti, A.; Reass, W.; Reece, K.; Rees, D.; Regan, A.; Regis, M.; Reijonen, J.; Rej, D.; Richards, D.; Richied, D.; Rode, C.; Rodriguez, W.; Rodriguez, M.; Rohlev, A.; Rose, C.; Roseberry, T.; Rowton, L.; Roybal, W.; Rust, K.; Salazer, G.; Sandberg, J.; Saunders, J.; Schenkel, T.; Schneider, W.; Schrage, D.; Schubert, J.; Severino, F.; Shafer, R.; Shea, T.; Shishlo, A.; Shoaee, H.; Sibley, C.; Sims, J.; Smee, S.; Smith, J.; Smith, K.; Spitz, R.; Staples, J.; Stein, P.; Stettler, M.; Stirbet, M.; Stockli, M.; Stone, W.; Stout, D.; Stovall, J.; Strelo, W.; Strong, H.; Sundelin, R.; Syversrud, D.; Szajbler, M.; Takeda, H.; Tallerico, P.; Tang, J.; Tanke, E.; Tepikian, S.; Thomae, R.; Thompson, D.; Thomson, D.; Thuot, M.; Treml, C.; Tsoupas, N.; Tuozzolo, J.; Tuzel, W.; Vassioutchenko, A.; Virostek, S.; Wallig, J.; Wanderer, P.; Wang, Y.; Wang, J. G.; Wangler, T.; Warren, D.; Wei, J.; Weiss, D.; Welton, R.; Weng, J.; Weng, W.-T.; Wezensky, M.; White, M.; Whitlatch, T.; Williams, D.; Williams, E.; Wilson, K.; Wiseman, M.; Wood, R.; Wright, P.; Wu, A.; Ybarrolaza, N.; Young, K.; Young, L.; Yourd, R.; Zachoszcz, A.; Zaltsman, A.; Zhang, S.; Zhang, W.; Zhang, Y.; Zhukov, A.

    2014-11-01

    The Spallation Neutron Source (SNS) was designed and constructed by a collaboration of six U.S. Department of Energy national laboratories. The SNS accelerator system consists of a 1 GeV linear accelerator and an accumulator ring providing 1.4 MW of proton beam power in microsecond-long beam pulses to a liquid mercury target for neutron production. The accelerator complex consists of a front-end negative hydrogen-ion injector system, an 87 MeV drift tube linear accelerator, a 186 MeV side-coupled linear accelerator, a 1 GeV superconducting linear accelerator, a 248-m circumference accumulator ring and associated beam transport lines. The accelerator complex is supported by ~100 high-power RF power systems, a 2 K cryogenic plant, ~400 DC and pulsed power supply systems, ~400 beam diagnostic devices and a distributed control system handling ~100,000 I/O signals. The beam dynamics design of the SNS accelerator is presented, as is the engineering design of the major accelerator subsystems.

  2. Worker hazards associated with the use of grain vacuum systems.

    PubMed

    Field, W E; Heber, D J; Riedel, S M; Wettschurack, S W; Roberts, M J; Grafft, L J

    2014-07-01

    Over the past two decades, there has been more widespread use of pneumatic handling of grain at commercial grain storage facilities and on farms as these operations have increased grain storage capacity and handle larger volumes of grain and feed In some cases, manufacturers have suggested that the use of these systems is a safer alternative to removing residual grain manually in conjunction with the use of sweep augers. The use of grain vacuum systems has also been increasingly documented as a strategy in responding to grain storage fires and human entrapment and engulfment in flowing grain. With greater utilization of these machines have come reports of entrapments and engulfments. This article summarizes 27 such documented incidents, including 21 fatalities, that resulted from the use of portable grain vacuum systems. It includes specific recommendations for engineering, educational, and regulatory strategies to reduce the risks associated with the use of these systems. PMID:25174148

  3. First Observations of Laser-Driven Acceleration of Relativistic Electrons in a Semi-Infinite Vacuum Space

    SciTech Connect

    Plettner, T.; Byer, R.L.; Smith, T.I.; Colby, E.; Cowan, B.; Sears, C.M.S.; Spencer, J.E.; Siemann, R.H.; /SLAC

    2006-02-17

    We have observed acceleration of relativistic electrons in vacuum driven by a linearly polarized visible laser beam incident on a thin gold-coated reflective boundary. The observed energy modulation effect follows all the characteristics expected for linear acceleration caused by a longitudinal electric field. As predicted by the Lawson-Woodward theorem the laser driven modulation only appears in the presence of the boundary. It shows a linear dependence with the strength of the electric field of the laser beam and also it is critically dependent on the laser polarization. Finally, it appears to follow the expected angular dependence of the inverse transition radiation process. experiment as the Laser Electron Accelerator Project (LEAP).

  4. Accelerating oscillatory fronts in a nonlinear sonic vacuum with strong nonlocal effects.

    PubMed

    Gendelman, O V; Zolotarevskiy, V; Savin, A V; Bergman, L A; Vakakis, A F

    2016-03-01

    We describe and explore accelerating oscillatory fronts in sonic vacua with nonlocal interactions. As an example, a chain of particles oscillating in the plane and coupled by linear springs, with fixed ends, is considered. When one end of this system is harmonically excited in the transverse direction, one observes accelerated propagation of the excitation front, accompanied by an almost monochromatic oscillatory tail. Position of the front obeys the scaling law l(t) ∼ t(4/3). The frequency of the oscillatory tail remains constant, and the wavelength scales as λ ∼ t(1/3). These scaling laws result from the nonlocal effects; we derive them analytically (including the scaling coefficients) from a continuum approximation. Moreover, a certain threshold excitation amplitude is required in order to initiate the front propagation. The initiation threshold is evaluated on the basis of a simplified discrete model, further reduced to a completely integrable nonlinear system. Given their simplicity, nonlinear sonic vacua of the type considered herein should be common in periodic lattices. PMID:27078353

  5. Accelerating oscillatory fronts in a nonlinear sonic vacuum with strong nonlocal effects

    NASA Astrophysics Data System (ADS)

    Gendelman, O. V.; Zolotarevskiy, V.; Savin, A. V.; Bergman, L. A.; Vakakis, A. F.

    2016-03-01

    We describe and explore accelerating oscillatory fronts in sonic vacua with nonlocal interactions. As an example, a chain of particles oscillating in the plane and coupled by linear springs, with fixed ends, is considered. When one end of this system is harmonically excited in the transverse direction, one observes accelerated propagation of the excitation front, accompanied by an almost monochromatic oscillatory tail. Position of the front obeys the scaling law l (t ) ˜t4 /3 . The frequency of the oscillatory tail remains constant, and the wavelength scales as λ ˜t1 /3 . These scaling laws result from the nonlocal effects; we derive them analytically (including the scaling coefficients) from a continuum approximation. Moreover, a certain threshold excitation amplitude is required in order to initiate the front propagation. The initiation threshold is evaluated on the basis of a simplified discrete model, further reduced to a completely integrable nonlinear system. Given their simplicity, nonlinear sonic vacua of the type considered herein should be common in periodic lattices.

  6. Commissioning of the vacuum system of the KATRIN Main Spectrometer

    NASA Astrophysics Data System (ADS)

    Arenz, M.; Babutzka, M.; Bahr, M.; Barrett, J. P.; Bauer, S.; Beck, M.; Beglarian, A.; Behrens, J.; Bergmann, T.; Besserer, U.; Blümer, J.; Bodine, L. I.; Bokeloh, K.; Bonn, J.; Bornschein, B.; Bornschein, L.; Büsch, S.; Burritt, T. H.; Chilingaryan, S.; Corona, T. J.; De Viveiros, L.; Doe, P. J.; Dragoun, O.; Drexlin, G.; Dyba, S.; Ebenhöch, S.; Eitel, K.; Ellinger, E.; Enomoto, S.; Erhard, M.; Eversheim, D.; Fedkevych, M.; Felden, A.; Fischer, S.; Formaggio, J. A.; Fränkle, F.; Furse, D.; Ghilea, M.; Gil, W.; Glück, F.; Gonzalez Ureña, A.; Görhardt, S.; Groh, S.; Grohmann, S.; Grössle, R.; Gumbsheimer, R.; Hackenjos, M.; Hannen, V.; Harms, F.; Haußmann, N.; Heizmann, F.; Helbing, K.; Herz, W.; Hickford, S.; Hilk, D.; Hillen, B.; Höhn, T.; Holzapfel, B.; Hötzel, M.; Howe, M. A.; Huber, A.; Jansen, A.; Kernert, N.; Kippenbrock, L.; Kleesiek, M.; Klein, M.; Kopmann, A.; Kosmider, A.; Kovalík, A.; Krasch, B.; Kraus, M.; Krause, H.; Krause, M.; Kuckert, L.; Kuffner, B.; La Cascio, L.; Lebeda, O.; Leiber, B.; Letnev, J.; Lobashev, V. M.; Lokhov, A.; Malcherek, E.; Mark, M.; Martin, E. L.; Mertens, S.; Mirz, S.; Monreal, B.; Müller, K.; Neuberger, M.; Neumann, H.; Niemes, S.; Noe, M.; Oblath, N. S.; Off, A.; Ortjohann, H.-W.; Osipowicz, A.; Otten, E.; Parno, D. S.; Plischke, P.; Poon, A. W. P.; Prall, M.; Priester, F.; Ranitzsch, P. C.-O.; Reich, J.; Rest, O.; Robertson, R. G. H.; Röllig, M.; Rosendahl, S.; Rupp, S.; Ryšavý, M.; Schlösser, K.; Schlösser, M.; Schönung, K.; Schrank, M.; Schwarz, J.; Seiler, W.; Seitz-Moskaliuk, H.; Sentkerestiová, J.; Skasyrskaya, A.; Slezák, M.; Špalek, A.; Steidl, M.; Steinbrink, N.; Sturm, M.; Suesser, M.; Telle, H. H.; Thümmler, T.; Titov, N.; Tkachev, I.; Trost, N.; Unru, A.; Valerius, K.; Vénos, D.; Vianden, R.; Vöcking, S.; Wall, B. L.; Wandkowsky, N.; Weber, M.; Weinheimer, C.; Weiss, C.; Welte, S.; Wendel, J.; Wierman, K. L.; Wilkerson, J. F.; Winzen, D.; Wolf, J.; Wüstling, S.; Zacher, M.; Zadoroghny, S.; Zbořil, M.

    2016-04-01

    The KATRIN experiment will probe the neutrino mass by measuring the β-electron energy spectrum near the endpoint of tritium β-decay. An integral energy analysis will be performed by an electro-static spectrometer (``Main Spectrometer''), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m3, and a complex inner electrode system with about 120 000 individual parts. The strong magnetic field that guides the β-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. A system consisting of 6 turbo-molecular pumps and 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300 °C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10‑11 mbar range. It is demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.

  7. Structure Loaded Vacuum Laser-Driven Particle Acceleration Experiments at SLAC

    SciTech Connect

    Plettner, T.; Byer, R.L.; Colby, E.R.; Cowan, B.M.; Ischebeck, R.; McGuinness, C.; Lincoln, M.R.; Sears, C.M.; Siemann, R.H.; Spencer, J.E.; /SLAC /Stanford U., Phys. Dept.

    2007-04-09

    We present an overview of the future laser-driven particle acceleration experiments. These will be carried out at the E163 facility at SLAC. Our objectives include a reconfirmation of the proof-of-principle experiment, a staged buncher laser-accelerator experiment, and longer-term future experiments that employ dielectric laser-accelerator microstructures.

  8. Vacuum chamber eddy current self-correction for the AGS Booster Accelerator

    SciTech Connect

    Danby, G.T.; Jackson, J.W.

    1989-01-01

    The large sextupole and other multipoles induced by eddy currents in the vacuum chamber (VC) designed for the AGS Booster dipoles have been cancelled by simple coils attached to the VC surface. A two turns per pole back leg winding provides the mmf required to power the correction coil by transformer action, automatically correcting even for the variable {dot B} magnet excitation. Much larger VC positional errors of translation and rotation are acceptable because the coils follow the VC contour: the aberrations and their corrections locally have the same misplaced coordinate system. The self-correction concept could be applied to quadrupoles. However, Booster quadrupole measurements show that induced higher harmonics from VC and other eddy current sources are very small. Thus, with self-correction of the dipole VC eddy current fields, {dot B} effects on the proton rapid cycling Booster optics are reduced to tracking of the fundamental dipole and quadrupole fields. This can be automatically controlled using field monitoring transducers located in a dipole and quadrupole operated in series with the Booster magnets. 2 refs., 4 figs.

  9. Fernald vacuum transfer system for uranium materials repackaging

    SciTech Connect

    Kaushiva, Shirley; Weekley, Clint; Molecke, Martin; Polansky, Gary

    2002-02-24

    The Fernald Environmental Management Project (FEMP) is the site of a former Department of Energy (DOE) uranium processing plant. When production was halted, many materials were left in an intermediate state. Some of this product material included enriched uranium compounds that had to be repackaged for shipment of off-site storage. This paper provides an overview, technical description, and status of a new application of existing technology, a vacuum transfer system, to repackage the uranium bearing compounds for shipment. The vacuum transfer system provides a method of transferring compounds from their current storage configuration into packages that meet the Department of Transportation (DOT) shipping requirements for fissile materials. This is a necessary activity, supporting removal of nuclear materials prior to site decontamination and decommissioning, key to the Fernald site's closure process.

  10. Diffuser-ejector system for a very high vacuum environment

    SciTech Connect

    Riggs, K.E.

    1984-06-19

    A system for testing space engines at sea level under a very low pressure environment. The system includes a space simulation chamber connected to a diffuser, which has two variable area ratio ejectors connected to it in tandem. Each of the ejectors is driven by a jet engine, preferably a turbo jet. The system is capable of providing a low pressure environment of about three or four millimeters of mercury for testing of engines mounted in the space simulation chamber. The system also may be used for other purposes requiring very high vacuum, such as evaporation and dehydration of food products or drugs.

  11. TMX-Upgrade vacuum-system design and analysis

    SciTech Connect

    Simonen, T.C.; Chargin, A.K.; Drake, R.P.; Nexsen, W.E.; Pickles, W.L.; Poulsen, P.; Stack, T.P.; Wong, R.L.

    1981-10-01

    This paper describes the design and analysis of the TMX Upgrade Vacuum System. TMX Upgrade is a modification of the TMX tandem mirror device. It will employ thermal barriers to further improve plasma confinement. Thermal barriers are produced by microwave heating and neutral-beam pumping. They increase the feasibility of tandem-mirror reactors by reducing both the required magnetic field strengths and the neutral-beam injection voltages.

  12. Degassing a vacuum system with in-situ UV radiation

    SciTech Connect

    Koebley, Sean R.; Outlaw, Ronald A.; Dellwo, Randy R.

    2012-11-15

    Photon-stimulated desorption (PSD) from a high-powered ultraviolet source was investigated as a technique to degas a vacuum system. A stainless steel vacuum system was pumped down from atmosphere with different time doses of 185 nm light, and the resulting outgassing rates were compared to that of a control pumpdown without UV assistance. PSD was found to provide a factor of 2 advantage in pumpdown pressure after only 30 min of UV exposure, with no additional advantage observed for longer irradiation times. Specifically, an outgassing rate of 3 Multiplication-Sign 10{sup -10} Torr L s{sup -1} cm{sup -2} was reached 3 h sooner in pumpdowns with UV assistance compared to those without UV, while a rate of 1.2 Multiplication-Sign 10{sup -10} Torr L s{sup -1} cm{sup -2} was reached 16 h sooner in UV runs. The authors calculated that about 22 monolayers of water were desorbed after 30 min of UV exposure. The results indicate that PSD by a 40 W 185 nm UV source can serve as a nonthermal technique to significantly speed the pumpdown of a vacuum system from atmosphere after only 30 min.

  13. Accelerator System Development at High Voltage Engineering

    SciTech Connect

    Klein, M. G.; Gottdang, A.; Haitsma, R. G.; Mous, D. J. W.

    2009-03-10

    Throughout the years, HVE has continuously extended the capabilities of its accelerator systems to meet the rising demands from a diverse field of applications, among which are deep level ion implantation, micro-machining, neutron production for biomedical research, isotope production or accelerator mass spectrometry. Characteristic for HVE accelerators is the coaxial construction of the all solid state power supply around the acceleration tubes. With the use of solid state technology, the accelerators feature high stability and very low ripple. Terminal voltages range from 1 to 6 MV for HVE Singletrons and Tandetrons. The high-current versions of these accelerators can provide ion beams with powers of several kW. In the last years, several systems have been built with terminal voltages of 1.25 MV, 2 MV and 5 MV. Recently, the first system based on a 6 MV Tandetron has passed the factory tests. In this paper we describe the characteristics of the HVE accelerator systems and present as example recent systems.

  14. A low cost imaging displacement measurement system for spacecraft thermal vacuum testing

    NASA Technical Reports Server (NTRS)

    Dempsey, Brian

    2006-01-01

    A low cost imaging displacement technique suitable for use in thermal vacuum testing was built and tested during thermal vacuum testing of the space infrared telescope facility (SIRTF, later renamed Spitzer infrared telescope facility). The problem was to measure the relative displacement of different portions of the spacecraft due to thermal expansion or contraction. Standard displacement measuring instrumentation could not be used because of the widely varying temperatures on the spacecraft and for fear of invalidating the thermal vacuum testing. The imaging system was conceived, designed, purchased, and installed in approximately 2 months at very low cost. The system performed beyond expectations proving that sub millimeter displacements could be measured from over 2 meters away. Using commercial optics it was possible to make displacement measurements down to 10 (mu)m. An automated image processing tool was used to process the data, which not only speeded up data reduction, but showed that velocities and accelerations could also be measured. Details of the design and capabilities of the system are discussed along with the results of the test on the observatory. Several images from the actual test are presented.

  15. Development of design technique for vacuum insulation in large size multi-aperture multi-grid accelerator for nuclear fusion.

    PubMed

    Kojima, A; Hanada, M; Tobari, H; Nishikiori, R; Hiratsuka, J; Kashiwagi, M; Umeda, N; Yoshida, M; Ichikawa, M; Watanabe, K; Yamano, Y; Grisham, L R

    2016-02-01

    Design techniques for the vacuum insulation have been developed in order to realize a reliable voltage holding capability of multi-aperture multi-grid (MAMuG) accelerators for fusion application. In this method, the nested multi-stage configuration of the MAMuG accelerator can be uniquely designed to satisfy the target voltage within given boundary conditions. The evaluation of the voltage holding capabilities of each acceleration stages was based on the previous experimental results about the area effect and the multi-aperture effect. Since the multi-grid effect was found to be the extension of the area effect by the total facing area this time, the total voltage holding capability of the multi-stage can be estimated from that per single stage by assuming the stage with the highest electric field, the total facing area, and the total apertures. By applying these consideration, the analysis on the 3-stage MAMuG accelerator for JT-60SA agreed well with the past gap-scan experiments with an accuracy of less than 10% variation, which demonstrated the high reliability to design MAMuG accelerators and also multi-stage high voltage bushings. PMID:26932032

  16. Development of design technique for vacuum insulation in large size multi-aperture multi-grid accelerator for nuclear fusion

    NASA Astrophysics Data System (ADS)

    Kojima, A.; Hanada, M.; Tobari, H.; Nishikiori, R.; Hiratsuka, J.; Kashiwagi, M.; Umeda, N.; Yoshida, M.; Ichikawa, M.; Watanabe, K.; Yamano, Y.; Grisham, L. R.

    2016-02-01

    Design techniques for the vacuum insulation have been developed in order to realize a reliable voltage holding capability of multi-aperture multi-grid (MAMuG) accelerators for fusion application. In this method, the nested multi-stage configuration of the MAMuG accelerator can be uniquely designed to satisfy the target voltage within given boundary conditions. The evaluation of the voltage holding capabilities of each acceleration stages was based on the previous experimental results about the area effect and the multi-aperture effect. Since the multi-grid effect was found to be the extension of the area effect by the total facing area this time, the total voltage holding capability of the multi-stage can be estimated from that per single stage by assuming the stage with the highest electric field, the total facing area, and the total apertures. By applying these consideration, the analysis on the 3-stage MAMuG accelerator for JT-60SA agreed well with the past gap-scan experiments with an accuracy of less than 10% variation, which demonstrated the high reliability to design MAMuG accelerators and also multi-stage high voltage bushings.

  17. Positron bunching and electrostatic transport system for the production and emission of dense positronium clouds into vacuum

    NASA Astrophysics Data System (ADS)

    Aghion, S.; Amsler, C.; Ariga, A.; Ariga, T.; Belov, A. S.; Bonomi, G.; Bräunig, P.; Bremer, J.; Brusa, R. S.; Cabaret, L.; Caccia, M.; Caravita, R.; Castelli, F.; Cerchiari, G.; Chlouba, K.; Cialdi, S.; Comparat, D.; Consolati, G.; Demetrio, A.; Di Noto, L.; Doser, M.; Dudarev, A.; Ereditato, A.; Evans, C.; Fesel, J.; Fontana, A.; Forslund, O. K.; Gerber, S.; Giammarchi, M.; Gligorova, A.; Gninenko, S.; Guatieri, F.; Haider, S.; Holmestad, H.; Huse, T.; Jernelv, I. L.; Jordan, E.; Kaltenbacher, T.; Kellerbauer, A.; Kimura, M.; Koetting, T.; Krasnicky, D.; Lagomarsino, V.; Lebrun, P.; Lansonneur, P.; Lehner, S.; Liberadzka, J.; Malbrunot, C.; Mariazzi, S.; Marx, L.; Matveev, V.; Mazzotta, Z.; Nebbia, G.; Nedelec, P.; Oberthaler, M.; Pacifico, N.; Pagano, D.; Penasa, L.; Petracek, V.; Pistillo, C.; Prelz, F.; Prevedelli, M.; Ravelli, L.; Rienäcker, B.; Røhne, O. M.; Rosenberger, S.; Rotondi, A.; Sacerdoti, M.; Sandaker, H.; Santoro, R.; Scampoli, P.; Sorrentino, F.; Spacek, M.; Storey, J.; Strojek, I. M.; Testera, G.; Tietje, I.; Vamosi, S.; Widmann, E.; Yzombard, P.; Zavatarelli, S.; Zmeskal, J.

    2015-11-01

    We describe a system designed to re-bunch positron pulses delivered by an accumulator supplied by a positron source and a Surko-trap. Positron pulses from the accumulator are magnetically guided in a 0.085 T field and are injected into a region free of magnetic fields through a μ -metal field terminator. Here positrons are temporally compressed, electrostatically guided and accelerated towards a porous silicon target for the production and emission of positronium into vacuum. Positrons are focused in a spot of less than 4 mm FWTM in bunches of ∼8 ns FWHM. Emission of positronium into the vacuum is shown by single shot positron annihilation lifetime spectroscopy.

  18. Radiation Safety Systems for Accelerator Facilities

    SciTech Connect

    Liu, James C

    2001-10-17

    The Radiation Safety System (RSS) of an accelerator facility is used to protect people from prompt radiation hazards associated with accelerator operation. The RSS is a fully interlocked, engineered system with a combination of passive and active elements that are reliable, redundant, and fail-safe. The RSS consists of the Access Control System (ACS) and the Radiation Containment System (RCS). The ACS is to keep people away from the dangerous radiation inside the shielding enclosure. The RCS limits and contains the beam/radiation conditions to protect people from the prompt radiation hazards outside the shielding enclosure in both normal and abnormal operations. The complexity of a RSS depends on the accelerator and its operation, as well as associated hazard conditions. The approaches of RSS among different facilities can be different. This report gives a review of the RSS for accelerator facilities.

  19. Radiation Safety Systems for Accelerator Facilities

    SciTech Connect

    James C. Liu; Jeffrey S. Bull; John Drozdoff; Robert May; Vaclav Vylet

    2001-10-01

    The Radiation Safety System (RSS) of an accelerator facility is used to protect people from prompt radiation hazards associated with accelerator operation. The RSS is a fully interlocked, engineered system with a combination of passive and active elements that are reliable, redundant, and fail-safe. The RSS consists of the Access Control System (ACS) and the Radiation Containment System (RCS). The ACS is to keep people away from the dangerous radiation inside the shielding enclosure. The RCS limits and contains the beam/radiation conditions to protect people from the prompt radiation hazards outside the shielding enclosure in both normal and abnormal operations. The complexity of a RSS depends on the accelerator and its operation, as well as associated hazard conditions. The approaches of RSS among different facilities can be different. This report gives a review of the RSS for accelerator facilities.

  20. Low-Cost, Rugged High-Vacuum System

    NASA Technical Reports Server (NTRS)

    Sorensen, Paul; Kline-Schoder, Robert

    2012-01-01

    A need exists for miniaturized, rugged, low-cost high-vacuum systems. Recent advances in sensor technology have led to the development of very small mass spectrometer detectors as well as other analytical instruments such as scanning electron microscopes. However, the vacuum systems to support these sensors remain large, heavy, and power-hungry. To meet this need, a miniaturized vacuum system was developed based on a very small, rugged, and inexpensive-to-manufacture molecular drag pump (MDP). The MDP is enabled by a miniature, very-high-speed (200,000 rpm), rugged, low-power, brushless DC motor optimized for wide temperature operation and long life. The key advantages of the pump are reduced cost and improved ruggedness compared to other mechanical hig-hvacuum pumps. The machining of the rotor and stators is very simple compared to that necessary to fabricate rotor and stator blades for other pump designs. Also, the symmetry of the rotor is such that dynamic balancing of the rotor will likely not be necessary. Finally, the number of parts in the unit is cut by nearly a factor of three over competing designs. The new pump forms the heart of a complete vacuum system optimized to support analytical instruments in terrestrial applications and on spacecraft and planetary landers. The MDP achieves high vacuum coupled to a ruggedized diaphragm rough pump. Instead of the relatively complicated rotor and stator blades used in turbomolecular pumps, the rotor in the MDP consists of a simple, smooth cylinder of aluminum. This will turn at approximately 200,000 rpm inside an outer stator housing. The pump stator comprises a cylindrical aluminum housing with one or more specially designed grooves that serve as flow channels. To minimize the length of the pump, the gas is forced down the flow channels of the outer stator to the base of the pump. The gas is then turned and pulled toward the top through a second set of channels cut into an inner stator housing that surrounds the

  1. Two-color-laser-driven direct electron acceleration in infinite vacuum.

    PubMed

    Wong, Liang Jie; Kärtner, Franz X

    2011-03-15

    We propose a direct electron acceleration scheme that uses a two-color pulsed radially polarized laser beam. The two-color scheme achieves electron acceleration exceeding 90% of the theoretical energy gain limit, over twice of what is possible with a one-color pulsed beam of equal total energy and pulse duration. The scheme succeeds by exploiting the Gouy phase shift to cause an acceleration-favoring interference of fields only as the electron enters its effectively final accelerating cycle. Optimization conditions and power scaling characteristics are discussed. PMID:21403741

  2. David Florida Laboratory Thermal Vacuum Data Processing System

    NASA Technical Reports Server (NTRS)

    Choueiry, Elie

    1994-01-01

    During 1991, the Space Simulation Facility conducted a survey to assess the requirements and analyze the merits for purchasing a new thermal vacuum data processing system for its facilities. A new, integrated, cost effective PC-based system was purchased which uses commercial off-the-shelf software for operation and control. This system can be easily reconfigured and allows its users to access a local area network. In addition, it provides superior performance compared to that of the former system which used an outdated mini-computer and peripheral hardware. This paper provides essential background on the old data processing system's features, capabilities, and the performance criteria that drove the genesis of its successor. This paper concludes with a detailed discussion of the thermal vacuum data processing system's components, features, and its important role in supporting our space-simulation environment and our capabilities for spacecraft testing. The new system was tested during the ANIK E spacecraft test, and was fully operational in November 1991.

  3. Vacuum system for the LBL Advanced Light Source (ALS)

    SciTech Connect

    Kennedy, K.; Henderson, T.; Meneghetti, J. )

    1989-03-01

    A 1.5 to 1.9 GeV synchrotron light source is being built at LBL. The vacuum system is designed to permit most synchrotron photons to escape the electron channel and be absorbed in an antechamber. The gas generated by the photons hitting the absorbers in the antechambers will be pumped by titanium sublimation pumps located directly under the absorbers. The electron channel and the antechamber are connected by a 10-mm-high slot that offers good electrodynamic isolation of the two chambers of frequencies affecting the store electron orbit. Twelve 10-meter-long vessels constitute the vacuum chambers for all the lattice magnets. Each chamber will be machined from two thick plates of 5083-H321 aluminum and welded at the perimeter. Machining both the inside and outside of the vacuum chamber permits the use of complex and accurate surfaces. The use of thick plates allows flanges to be machined directly into the wall of each chamber, thus avoiding much welding. 1 ref., 3 figs.

  4. Vacuum system for the LBL advanced light source (ALS)

    SciTech Connect

    Kennedy, K.

    1988-05-01

    A 1.5 to 1.9 GeV synchrotron light source is being built at LBL. The vacuum system is designed to permit all synchrotron photons on the median plane to escape the electron channel and go into an antechamber through a 10 mm high slot. This slot offers effective RF isolation between the electron duct and the antechamber. All unused synchrotron photons within a few mrad of the median plane will be stopped by 96 nearly horizontal absorbers located in the antechamber. The gas, generated by the photons hitting the absorbers, will be directed down to reactive titanium surfaces. Twelve 10 meter long vessels constitute the vacuum chambers for all the lattice magnets. Each chamber will be machined from two thick plates of 5083-H321 aluminum and welded at the perimeter. The nominal wall thickness of the vacuum chamber is 40 mm, which makes it possible to machine a flange into the chamber without the use of welding. 5 refs., 5 figs.

  5. Non-reclosing pressure relief device for vacuum systems

    DOEpatents

    Swansiger, William A.

    1994-01-01

    A non-reclosing overpressure protection device such as a rupture disc provides a non-reclosing opening upon forcible contact with a knife blade. A bellows, having an inlet capable of being sealably connected to a source of pressure (the vacuum system) and an outlet containing the rupture disc, transmits the pressure in the system to the disc. The bellows maintains the disc away from the knife when the pressure is below an overpressure amount, and carries the disc to a position when the pressure is above an overpressure amount where the disc is ruptured by the knife.

  6. Non-reclosing pressure relief device for vacuum systems

    DOEpatents

    Swansiger, W.A.

    1994-02-08

    A non-reclosing overpressure protection device such as a rupture disc provides a non-reclosing opening upon forcible contact with a knife blade. A bellows, having an inlet capable of being sealably connected to a source of pressure (the vacuum system) and an outlet containing the rupture disc, transmits the pressure in the system to the disc. The bellows maintains the disc away from the knife when the pressure is below an overpressure amount, and carries the disc to a position when the pressure is above an overpressure amount where the disc is ruptured by the knife. 6 figures.

  7. Cryogenic thermal storage system for discontinuous industrial vacuum processes

    NASA Astrophysics Data System (ADS)

    Bruzzi, M.; Chesi, A.; Baldi, A.; Tarani, F.; Mori, R.; Scaringella, M.; Carnevale, E.

    2012-10-01

    Phase Change Materials are proposed for refrigerating systems in discontinuous industrial vacuum processes where temperatures as low as -140 ÷ -100°C are necessary within time-frames representing 10÷20% of total operating time. An application is proposed for cooling systems used in a Physical Vapour Deposition (PVD) apparatus. A prototype has been manufactured which couples a cryopump with a reservoir filled with MethylCycloPentane (MCP-C6H12) and a distribution line where nitrogen in the gaseous state is flowing. Preliminary tests show that temperatures of about -120°C are actually achieved within time windows compatible with PVD applications.

  8. Technology Demonstration Summary: Terra Vac In Situ Vacuum Extraction System, Groveland, Massachusetts

    EPA Science Inventory

    Terra Vac Inc's vacuum extraction system was demonstrated at the Valley Manufactured Products Company, Inc., site in Groveland, Massachusetts. The property is part of the Groveland Wells Superfund site and is contaminated mainly by trichloroethylene (TCE). Vacuum extraction...

  9. Advanced Microgravity Acceleration Measurement Systems Being Developed

    NASA Technical Reports Server (NTRS)

    Sicker, Ronald J.; Kacpura, Thomas J.

    2002-01-01

    The Advanced Microgravity Acceleration Measurement Systems (AMAMS) project at the NASA Glenn Research Center is part of the Instrument Technology Development program to develop advanced sensor systems. The primary focus of the AMAMS project is to develop microelectromechanical (MEMS) acceleration sensor systems to replace existing electromechanical-sensor-based systems presently used to assess relative gravity levels aboard spacecraft. These systems are used in characterizing both vehicle and payload responses to low-gravity vibroacoustic environments. The collection of microgravity acceleration data has cross-disciplinary utility to the microgravity life and physical sciences and the structural dynamics communities. The inherent advantages of semiconductor-based systems are reduced size, mass, and power consumption, while providing enhanced stability.

  10. Vehicle Systems Integration Laboratory Accelerates Powertrain Development

    SciTech Connect

    2014-04-15

    ORNL's Vehicle Systems Integration (VSI) Laboratory accelerates the pace of powertrain development by performing prototype research and characterization of advanced systems and hardware components. The VSI Lab is capable of accommodating a range of platforms from advanced light-duty vehicles to hybridized Class 8 powertrains with the goals of improving overall system efficiency and reducing emissions.

  11. Vehicle Systems Integration Laboratory Accelerates Powertrain Development

    ScienceCinema

    None

    2014-06-25

    ORNL's Vehicle Systems Integration (VSI) Laboratory accelerates the pace of powertrain development by performing prototype research and characterization of advanced systems and hardware components. The VSI Lab is capable of accommodating a range of platforms from advanced light-duty vehicles to hybridized Class 8 powertrains with the goals of improving overall system efficiency and reducing emissions.

  12. Hydrodynamic vacuum sources of dark matter self-generation in an accelerating universe without a Big Bang

    SciTech Connect

    Chefranov, S. G.; Novikov, E. A.

    2010-11-15

    We have obtained a generalization of the hydrodynamic theory of vacuum in the context of general relativity. While retaining the Lagrangian character of general relativity, the new theory provides a natural alternative to the view that the singularity is inevitable in general relativity and the theory of a hot Universe. We show that the macroscopic source-sink motion as a whole of ordinary (dark) matter that emerges during the production of particles out of the vacuum can be a new source of gravitational vacuum polarization (determining the variability of the cosmological term in general relativity). We have removed the well-known problems of the cosmological constant by refining the physical nature of dark energy associated precisely with this hydrodynamically initiated variability of the vacuum energy density. A new exact solution of the modified general relativity equations that contains no free (fitting) parameter additional to those available in general relativity has been obtained. It corresponds to the continuous and metric-affecting production of ultralight dark matter particles (with mass m{sub 0} = ({h_bar}/c{sup 2}) {approx} 3 x 10{sup -66} g, k is the gravitational constant) out of the vacuum, with its density {rho}{sub 0}, constant during the exponential expansion of a spatially flat Universe, being retained. This solution is shown to be stable in the regime of cosmological expansion in the time interval -{infinity} < t < t{sub max}, when t = 0 corresponds to the present epoch and t{sub max}= 2/3H{sub 0}c{Omega}{sub 0m} {approx} 38 x 10{sup 9} yr at {Omega}{sub 0m} = {rho}{sub 0}/{rho}{sub c} {approx} 0.28 (H{sub 0} is the Hubble constant, {rho}{sub c} is the critical density). For t > t{sub max}, the solution becomes exponentially unstable and characterizes the inverse process of dark matter particle absorption by the vacuum in the regime of contraction of the Universe. We consider the admissibility of the fact that scalar massive photon pairs can be

  13. HRIBF Tandem Accelerator Radiation Safety System Upgrade

    SciTech Connect

    Blankenship, J.L.; Juras, R.C.

    1998-11-04

    The HRIBF Tandem Accelerator Radiation Safety System was designed to permit experimenters and operations staff controlled access to beam transport and experiment areas with accelerated beam present. Neutron-Gamma detectors are mounted in eaeh area at points of maximum dose rate and the resulting signals are integrated by redundan~ circuitry; beam is stopped if dose rate or integrated dose exceeds established limits. This paper will describe the system, in use for several vears at the HRIBF, and discuss changes recently made to modernize the system and to make the system compliant with DOE Order 5480.25 and related ORNL updated safety rules.

  14. HRIBF Tandem Accelerator Radiation Safety System Upgrade

    NASA Astrophysics Data System (ADS)

    Juras, R. C.; Blankenship, J. L.

    1999-06-01

    The HRIBF Tandem Accelerator Radiation Safety System was designed to permit experimenters and operations staff controlled access to beam transport and experiment areas with accelerated beam present. Neutron-Gamma detectors are mounted in each area at points of maximum dose rate and the resulting signals are integrated by redundant circuitry; beam is stopped if dose rate or integrated dose exceeds established limits. This paper will describe the system, in use for several years at the HRIBF, and discuss changes recently made to modernize the system and to make the system compliant with DOE Order 5480.25 and related ORNL updated safety rules.

  15. Space Acceleration Measurement System-II

    NASA Technical Reports Server (NTRS)

    Foster, William

    2009-01-01

    Space Acceleration Measurement System (SAMS-II) is an ongoing study of the small forces (vibrations and accelerations) on the ISS that result from the operation of hardware, crew activities, as well as dockings and maneuvering. Results will be used to generalize the types of vibrations affecting vibration-sensitive experiments. Investigators seek to better understand the vibration environment on the space station to enable future research.

  16. Application accelerator system having bunch control

    DOEpatents

    Wang, D.; Krafft, G.A.

    1999-06-22

    An application accelerator system for monitoring the gain of a free electron laser is disclosed. Coherent Synchrotron Radiation (CSR) detection techniques are used with a bunch length monitor for ultra short, picosec to several tens of femtosec, electron bunches. The monitor employs an application accelerator, a coherent radiation production device, an optical or beam chopping device, an infrared radiation collection device, a narrow-banding filter, an infrared detection device, and a control. 1 fig.

  17. Application accelerator system having bunch control

    DOEpatents

    Wang, Dunxiong; Krafft, Geoffrey Arthur

    1999-01-01

    An application accelerator system for monitoring the gain of a free electron laser. Coherent Synchrotron Radiation (CSR) detection techniques are used with a bunch length monitor for ultra short, picosec to several tens of femtosec, electron bunches. The monitor employs an application accelerator, a coherent radiation production device, an optical or beam chopping device, an infrared radiation collection device, a narrow-banding filter, an infrared detection device, and a control.

  18. The EMMA Accelerator, a Diagnostic Systems Overview

    SciTech Connect

    Kalinin, A.; Berg, J.; Bliss, N. Cox, G.; Dufau, M.; Gallagher, A.; Hill, C.; Jones, J.; Ma, L.; McIntosh, P.; Muratori, B.; Oates, A.; Shepherd B.; Smith, R.; Hock, K.; Holder, D.; Ibison, M., Kirkman I.; Borrell, R.; Crisp, J.; Fellenz, B.; Wendt, M.

    2011-09-04

    The 'EMMA' Non-Scaling Fixed Field Alternating Gradient (ns-FFAG) international project is currently being commissioned at Daresbury Laboratory, UK. This accelerator has been equipped with a number of diagnostic systems to facilitate this. These systems include a novel time-domain-multiplexing BPM system, moveable screen systems, a time-of-flight instrument, Faraday cups, and injection/extraction tomography sections to analyze the single bunch beams. An upgrade still to implement includes the installation of wall current monitors. This paper gives an overview of these systems and shows some data and results from the diagnostics that have contributed to the successful demonstration of a serpentine acceleration by this novel accelerator.

  19. Aluminium ultrahigh vacuum system for the 3 GeV TPS synchrotron light source

    NASA Astrophysics Data System (ADS)

    Hsiung, G. Y.; Chang, C. C.; Chen, C. L.; Wu, L. H.; Cheng, C. M.; Chan, C. K.; Yang, Y. C.; Hsueh, H. P.; Hsu, S. N.; Chen, J. R.

    2013-06-01

    The 3-GeV Taiwan Photon Source (TPS) is a large accelerator and synchrotron light source of circumference 518.4 m. The electron storage ring of TPS requires an ultrahigh-vacuum pressure per beam current less than 2×10-10 Pa/mA in the beam duct to maintain a long life of the circulating beam without scattering of ions by residual gases. Aluminium alloys used for the beam ducts have a benefit of greater thermal conductivity that simplifies the structure of vacuum vessels built with the cooling components. Machining completely free of oil applied to the aluminium chambers followed by cleaning with ozonized water and welding in house provide a precise dimensional control within 0.3 mm and a clean surface with a small rate ~ 6.4×10-12 Pa m/s of thermal outgassing after baking at 150 °C for 24 h. The assembled ion pump with non-evaporable getter pump is capable of evacuating the chamber to a pressure < 1×10-9 Pa. The average pressure inside the duct is expected to be sufficiently small. The clean process to manufacture the aluminium ultrahigh vacuum system is described.

  20. Observing quantum vacuum lensing in a neutron star binary system.

    PubMed

    Dupays, Arnaud; Robilliard, Cécile; Rizzo, Carlo; Bignami, Giovanni F

    2005-04-29

    In this Letter we study the propagation of light in the neighborhood of magnetized neutron stars. Because of the optical properties of quantum vacuum in the presence of a magnetic field, the light emitted by background astronomical objects is deviated, giving rise to a phenomenon of the same kind as the gravitational one. We give a quantitative estimation of this effect, and we discuss the possibility of its observation. We show that this effect could be detected by monitoring the evolution of the recently discovered double neutron star system J0737-3039. PMID:15904205

  1. Status of NSLS-II Storage Ring Vacuum Systems

    SciTech Connect

    Doom,L.; Hseuh,H.; Ferreira, M.; Longo, C.; Ravindranath, V.; Settepani, P.; Sharma, S.; Wilson, K.

    2009-05-04

    National Synchrotron Light Source II (NSLS-II), being constructed at Brookhaven National Laboratory, is a 3-GeV, high-flux and high- brightness synchrotron radiation facility with a nominal current of 500 mA. The storage ring vacuum system will have extruded aluminium chambers with ante-chamber for photon fans and distributed NEG strip pumping. Discrete photon absorbers will be used to intercept the un-used bending magnet radiation. In-situ bakeout will be implemented to achieve fast conditioning during initial commissioning and after interventions.

  2. Quartz microbalance device for transfer into ultrahigh vacuum systems

    SciTech Connect

    Stavale, F.; Achete, C. A.; Niehus, H.

    2008-10-15

    An uncomplicated quartz microbalance device has been developed which is transferable into ultrahigh vacuum (UHV) systems. The device is extremely useful for flux calibration of different kinds of material evaporators. Mounted on a commercial specimen holder, the device allows fast quartz microbalance transfer into the UHV and subsequent positioning exactly to the sample location where subsequent thin film deposition experiments shall be carried out. After backtransfer into an UHV sample stage, the manipulator may be loaded in situ with the specimen suited for the experiment. The microbalance device capability is demonstrated for monolayer and submonolayer vanadium depositions with an achieved calibration sensitivity of less the 0.001 ML coverage.

  3. RHIC Sextant Test - Accelerator Systems and Performance

    NASA Astrophysics Data System (ADS)

    Pilat, F.; Ahrens, L.; Brown, K.; Connolly, R.; dell, G. F.; Fischer, W.; Kewisch, J.; Mackay, W.; Mane, V.; Peggs, S.; Satogata, T.; Tepikian, S.; Thompson, P.; Trbojevic, D.; Tsoupas, N.; Wei, J.

    1997-05-01

    One sextant of the RHIC collider and the full AtR (AGS to RHIC) transfer line have been commissioned in early 1997 with beam. We describe here the design and performance of the accelerator systems during the test, such as the magnet and power supply systems, instrumentation subsystems and application software. After reviewing the main milestones of the commissioning we describe a ramping test without beam that took place after the commissioning with beam. Finally, we analyze the implications of accelerator systems preformance and their impact on the plannig for RHIC installation and commissioning.

  4. Fermilab accelerator control system: Analog monitoring facilities

    SciTech Connect

    Seino, K.; Anderson, L.; Smedinghoff, J.

    1987-10-01

    Thousands of analog signals are monitored in different areas of the Fermilab accelerator complex. For general purposes, analog signals are sent over coaxial or twinaxial cables with varying lengths, collected at fan-in boxes and digitized with 12 bit multiplexed ADCs. For higher resolution requirements, analog signals are digitized at sources and are serially sent to the control system. This paper surveys ADC subsystems that are used with the accelerator control systems and discusses practical problems and solutions, and it describes how analog data are presented on the console system.

  5. A large distributed digital camera system for accelerator beam diagnostics

    NASA Astrophysics Data System (ADS)

    Catani, L.; Cianchi, A.; Di Pirro, G.; Honkavaara, K.

    2005-07-01

    Optical diagnostics, providing images of accelerated particle beams using radiation emitted by particles impinging a radiator, typically a fluorescent screen, has been extensively used, especially on electron linacs, since the 1970's. Higher intensity beams available in the last decade allow extending the use of beam imaging techniques to perform precise measurements of important beam parameters such as emittance, energy, and energy spread using optical transition radiation (OTR). OTR-based diagnostics systems are extensively used on the superconducting TESLA Test Facility (TTF) linac driving the vacuum ultraviolet free electron laser (VUV-FEL) at the Deutsches Elektronen-Synchrotron facility. Up to 30 optical diagnostic stations have been installed at various positions along the 250-m-long linac, each equipped with a high-performance digital camera. This paper describes the new approach to the design of the hardware and software setups required by the complex topology of such a distributed camera system.

  6. Nanoparticle generation and interactions with surfaces in vacuum systems

    NASA Astrophysics Data System (ADS)

    Khopkar, Yashdeep

    beam in the tool could significantly accelerate particles. Assuming that these particles are transported to various surfaces inside the deposition tool, the next challenge is to enhance the adhesion of the particles on surfaces that are located in the non-critical areas inside the tool. However, for particles in the sub-100 nm size range, suitable methods do not exist that can compare the adhesion probability of particles upon impact for a wide range of impact velocities, surfaces and particle types. Traditional methods, which rely on optical measurement of particle velocities in the micron-size regime, cannot be used for sub-100 nm particles as the particles do not scatter sufficient light for the detectors to function. All the current methods rely on electrical measurements taken from impacting particles onto a surface. However, for sub-100 nm particles, the impact velocity varies in different regions of the same impaction spot. Therefore, electrical measurements are inadequate to quantify the exact adhesion characteristics at different impact velocities to enable a comparison of multiple particle-surface systems. Therefore, we propose a new method based on the use of scanning electron microscopy (SEM) imaging to study the adhesion of particles upon impact on surfaces. The use of SEM imaging allows for single particle detection across a single impaction spot and, therefore, enables the comparison of different regions with different impact velocities in a single impaction spot. The proposed method will provide comprehensive correlation between the adhesion probability of sub-100 nm particles and a wide range of impact velocities and angles. The location of each particle is compared with impact velocity predicted by using computational fluid dynamics methods to generate a comprehensive adhesion map involving the impact of 70 nm particles on a polished surface across a large impact velocity range. The final adhesion probability map shows higher adhesion at oblique

  7. Development of a Control System for the Teat-End Vacuum in Individual Quarter Milking Systems

    PubMed Central

    Ströbel, Ulrich; Rose-Meierhöfer, Sandra; Öz, Hülya; Brunsch, Reiner

    2013-01-01

    Progress in sensor technique and electronics has led to a decrease in the costs of electronic and sensor components. In modern dairy farms, having udders in good condition, a lower frequency of udder disease and an extended service life of dairy cows will help ensure competitiveness. The objective of this study was to develop a teat-end vacuum control system with individual quarter actor reaction. Based on a review of the literature, this system is assumed to protect the teat tissue. It reduces the mean teat-end vacuum in the maximum vacuum phase (b) to a level of 20 kPa at a flow rate of 0.25 L/min per quarter. At flow rates higher than 1.50 L/min per quarter, the teat-end vacuum can be controlled to a level of 30 kPa, because in this case it is desirable to have a higher vacuum for the transportation of the milk to the receiver. With this system it is possible for the first time to supply the teat end with low vacuum at low flow rates and with higher vacuum at increasing flow rates in a continuous process with a three second reaction-rate on individual quarter level. This system is completely automated. PMID:23765272

  8. The BNL Accelerator Test Facility control system

    SciTech Connect

    Malone, R.; Bottke, I.; Fernow, R.; Ben-Zvi, I.

    1993-01-01

    Described is the VAX/CAMAC-based control system for Brookhaven National Laboratory's Accelerator Test Facility, a laser/linac research complex. Details of hardware and software configurations are presented along with experiences of using Vsystem, a commercial control system package.

  9. Development of High Power Vacuum Tubes for Accelerators and Plasma Heating

    NASA Astrophysics Data System (ADS)

    Srivastava, Vishnu

    2012-11-01

    High pulsed power magnetrons and klystrons for medical and industrial accelerators, and high CW power klystrons and gyrotrons for plasma heating in tokamak, are being developed at CEERI. S-band 2.0MW pulsed tunable magnetrons of centre frequency 2856MHz and 2998 MHz were developed, and S-band 2.6MW pulsed tunable magnetron is being developed for medical LINAC, and 3MW pulsed tunable magnetron is being developed for industrial accelerator. S-band (2856MHz), 5MW pulsed klystron was developed for particle accelerator, and S-band 6MW pulsed klystron is under development for 10MeV industrial accelerator. 350MHz, 100kW (CW) klystron is being developed for proton accelerator, and C-band 250kW (CW) klystron is being developed for plasma heating. 42GHz, 200kW (CW/Long pulse) gyrotron is under development for plasma heating. Plasma filled tubes are also being developed for switching. 25kV/1kA and 40kV/3kA thyratrons were developed for high voltage high current switching in pulse modulators for magnetrons and klystrons. 25kV/3kA Pseudospark switch of current rise time of 1kA/|a-sec and pulse repetition rate of 500Hz is being developed. Plasma assisted high power microwave device is also being investigated.

  10. Thermal Vacuum Facility for Testing Thermal Protection Systems

    NASA Technical Reports Server (NTRS)

    Daryabeigi, Kamran; Knutson, Jeffrey R.; Sikora, Joseph G.

    2002-01-01

    A thermal vacuum facility for testing launch vehicle thermal protection systems by subjecting them to transient thermal conditions simulating re-entry aerodynamic heating is described. Re-entry heating is simulated by controlling the test specimen surface temperature and the environmental pressure in the chamber. Design requirements for simulating re-entry conditions are briefly described. A description of the thermal vacuum facility, the quartz lamp array and the control system is provided. The facility was evaluated by subjecting an 18 by 36 in. Inconel honeycomb panel to a typical re-entry pressure and surface temperature profile. For most of the test duration, the average difference between the measured and desired pressures was 1.6% of reading with a standard deviation of +/- 7.4%, while the average difference between measured and desired temperatures was 7.6% of reading with a standard deviation of +/- 6.5%. The temperature non-uniformity across the panel was 12% during the initial heating phase (t less than 500 sec.), and less than 2% during the remainder of the test.

  11. LLNL Tandem Mirror Experiment (TMX) upgrade vacuum system

    SciTech Connect

    Pickles, W.L.; Chargin, A.K.; Drake, R.P.

    1981-09-15

    TMX Upgrade is a large, tandem, magnetic-mirror fusion experiment with stringent requirements on base pressure (10/sup -8/ torr), low H reflux from the first walls, and peak gas pressure (5 x 10/sup -7/ torr) due to neutral beam gas during plasma operation. The 225 m/sup 3/ vacuum vessel is initially evacuated by turbopumps. Cryopumps provide a continuous sink for gases other than helium, deuterium, and hydrogen. The neutral beam system introduces up to 480 l/s of H or D. The hydrogen isotopes are pumped at very high speed by titanium sublimed onto two cylindrical radially separated stainless steel quilted liners with a total surface area of 540 m/sup 2/. These surfaces (when cooled to about 80/sup 0/K) provide a pumping speed of 6 x 10/sup 7/ l/s for hydrogen. The titanium getter system is programmable and is used for heating as well as gettering. The inner plasma liner can be operated at elevated temperatures to enhance migration of gases away from the surfaces close to the plasma. Glow discharge cleaning is part of the pumpdown procedure. The design features are discussed in conjunction with the operating procedures developed to manage the dynamic vacuum conditions.

  12. LLNL tandem mirror experiment (TMX) upgrade vacuum system

    SciTech Connect

    Pickles, W.L.; Chargin, A.K.; Drake, R.P.; Hunt, A.L.; Lang, D.D.; Murphy, J.J.; Poulsen, P.; Simonen, T.C.; Batzer, T.H.; Stack, T.P.; Wong, R.L.

    1982-04-01

    The tandem mirror experiment (TMX) upgrade is a large, tandem, magnetic-mirror fusion experiment with stringent requirements on base pressure (10/sup -8/ Torr), low H reflux from the first walls, and peak gas pressure (5 x 10/sup -7/ Torr) due to neutral beam gas during plasma operation. The 225 m/sup 3/ vacuum vessel is initially evacuated by turbopumps. Cryopumps provide a continuous sink for gases other than helium, deuterium, and hydrogen. The neutral beam system introduces up to 480 l/s of H or D. The hydrogen isotopes are pumped at very high speed by titanium sublimed onto two cylindrical radially separated stainless steel quilted liners with a total surface area of 540 m/sup 2/. These surfaces (when cooled to about 80 K) provide a pumping speed of 6 x 10/sup 7/ l/s for hydrogen. The titanium getter system is programmable and is used for heating as well as gettering. The inner plasma liner can be operated at elevated temperatures to enhance migration of gases away from the surfaces close to the plasma. Glow discharge cleaning is part of the pumpdown procedure. The design features are discussed in conjunction with the operating procedures developed to manage the dynamic vacuum conditions.

  13. THERMAL DESIGN OF THE ITER VACUUM VESSEL COOLING SYSTEM

    SciTech Connect

    Carbajo, Juan J; Yoder Jr, Graydon L; Kim, Seokho H

    2010-01-01

    RELAP5-3D models of the ITER Vacuum Vessel (VV) Primary Heat Transfer System (PHTS) have been developed. The design of the cooling system is described in detail, and RELAP5 results are presented. Two parallel pump/heat exchanger trains comprise the design one train is for full-power operation and the other is for emergency operation or operation at decay heat levels. All the components are located inside the Tokamak building (a significant change from the original configurations). The results presented include operation at full power, decay heat operation, and baking operation. The RELAP5-3D results confirm that the design can operate satisfactorily during both normal pulsed power operation and decay heat operation. All the temperatures in the coolant and in the different system components are maintained within acceptable operating limits.

  14. Subluminous phase velocity of a focused laser beam and vacuum laser acceleration.

    PubMed

    Pang, J; Ho, Y K; Yuan, X Q; Cao, N; Kong, Q; Wang, P X; Shao, L; Esarey, E H; Sessler, A M

    2002-12-01

    It has been found that for a focused laser beam propagating in free space, there exists, surrounding the laser beam axis, a subluminous wave phase velocity region. Relativistic electrons injected into this region can be trapped in the acceleration phase and remain in phase with the laser field for sufficiently long times, thereby receiving considerable energy from the field. Optics placed near the laser focus are not necessary, thus allowing high intensities and large energy gains. Important features of this process are examined via test particle simulations. The resulting energy gains are in agreement with theoretical estimates based on acceleration by the axial laser field. PMID:12513421

  15. Single photon ionization and chemical ionization combined ion source based on a vacuum ultraviolet lamp for orthogonal acceleration time-of-flight mass spectrometry.

    PubMed

    Hua, Lei; Wu, Qinghao; Hou, Keyong; Cui, Huapeng; Chen, Ping; Wang, Weiguo; Li, Jinghua; Li, Haiyang

    2011-07-01

    A novel combined ion source based on a vacuum ultraviolet (VUV) lamp with both single photon ionization (SPI) and chemical ionization (CI) capabilities has been developed for an orthogonal acceleration time-of-flight mass spectrometer (oaTOFMS). The SPI was accomplished using a commercial 10.6 eV krypton discharge lamp with a photon flux of about 10(11) photons s(-1), while the CI was achieved through ion-molecule reactions with O(2)(+) reactant ions generated by photoelectron ionization at medium vacuum pressure (MVP). To achieve high ionization efficiency, the ion source pressure was elevated to 0.3 mbar and the photoionization length was extended to 36 mm. As a result, limits of detection (LODs) down to 3, 4, and 6 ppbv were obtained for benzene, toluene, and p-xylene in MVP-SPI mode, and values of 8 and 10 ppbv were obtained for toluene and chloroform, respectively, in SPI-CI mode. As it is feasible to switch between MVP-SPI mode and SPI-CI mode rapidly, this system is capable of monitoring complex organic mixtures with a wide range of ionization energies (IEs). The analytical capacity of this system was demonstrated by measuring dehydrogenation products of long-chain paraffins to olefins through direct capillary sampling and drinking water disinfection byproducts from chlorine through a membrane interface. PMID:21591696

  16. Characterization of ion accelerating systems on NASA LeRC's ion thrusters

    NASA Technical Reports Server (NTRS)

    Rawlin, Vincent K.

    1992-01-01

    An investigation is conducted regarding ion-accelerating systems for two NASA thrusters to study the limits of ion-extraction capability or perveance. A total of nine two-grid ion-accelerating systems are tested with the 30- and 50-cm-diam ring-cusp inert-gas ion thrusters emphasizing the extension of ion-extraction. The vacuum-tank testing is described using xenon, krypton, and argon propellants, and thruster performance is computed with attention given to theoretical design considerations. Reductions in perveance are noted with decreasing accelerator-hole-to-screen-hole diameter ratios. Perveance values vary indirectly with the ratio of discharge voltage to total accelerating voltage, and screen/accelerator electrode hole-pair alignment is also found to contribute to perveance values.

  17. Heat transfer in vacuum packaged microelectromechanical system devices

    NASA Astrophysics Data System (ADS)

    Cai, Chunpei

    2008-01-01

    This study analyzes heat transfer effects inside vacuum packaged microelectromechanical system (MEMS) devices. A packaged device is simplified as four plates forming a square cavity, the bottom plate represents a hot chip, while the other three plates are maintained at room temperature. For a highly rarefied free molecular internal gas flow scenario, the corresponding detailed density and temperature fields are analytically determined with a proposed speculation. This speculation indicates that for a steady free molecular gas flow inside a convex closure domain formed by walls maintained at different temperatures: (1) the velocity distribution functions for those molecules diffusely reflected at different walls and traveling away from them are Maxwellian with different number densities; (2) for each distribution, ni√Ti is a constant, where ni is the number density for the group of reflected molecules, and Ti is the temperature for the ith plate. For a near continuum flow scenario, the governing energy equation degenerates to Laplace's equation with several temperature-jump wall boundary conditions. This study also includes discussions and comparisons among analytical results, simulation results from the direct simulation Monte Carlo method, and results by solving the Navier-Stokes equations with proper wall boundary conditions. The approach used in this study is generally applicable to study internal flows and heat transfer effects in other vacuum packaged MEMS devices with different shapes.

  18. Absolute calibration of vacuum ultraviolet spectrograph system for plasma diagnostics

    SciTech Connect

    Yoshikawa, M.; Kubota, Y.; Kobayashi, T.; Saito, M.; Numada, N.; Nakashima, Y.; Cho, T.; Koguchi, H.; Yagi, Y.; Yamaguchi, N.

    2004-10-01

    A space- and time-resolving vacuum ultraviolet (VUV) spectrograph system has been applied to diagnose impurity ions behavior in plasmas produced in the tandem mirror GAMMA 10 and the reversed field pinch TPE-RX. We have carried out ray tracing calculations for obtaining the characteristics of the VUV spectrograph and calibration experiments to measure the absolute sensitivities of the VUV spectrograph system for the wavelength range from 100 to 1100 A. By changing the incident angle, 50.6 deg. -51.4 deg., to the spectrograph whose nominal incident angle is 51 deg., we can change the observing spectral range of the VUV spectrograph. In this article, we show the ray tracing calculation results and absolute sensitivities when the angle of incidence into the VUV spectrograph is changed, and the results of VUV spectroscopic measurement in both GAMMA 10 and TPE-RX plasmas.

  19. Observation of THz emission from a laser-plasma accelerated electron bunch crossing a plasma-vacuum boundary

    SciTech Connect

    Leemans, W.P.; Geddes, C.G.R.; Faure, J.; Toth, Cs.; van Tilborg, J.; Schroeder, C.B.; Esarey, E.; Fubiani, G.; Auerbach, D.; Marcelis, B.; Carnahan, M.A.; Kaindl, R.A.; Byrd, J.; Martin, M.C.

    2003-04-15

    Coherent radiation in the 0.3 - 3 THz range has been generated from femto second electron bunches at a plasma-vacuum boundary via transition radiation. The bunches produced by a laser-plasma accelerator contained 1.5 nC of charge. The THz energy per pulse within a limited 30 mrad collection angle was 3.5 nJ and scaled quadratically with bunch charge, consistent with coherent emission. Modeling indicates that this broadband source produces about 0.3 muJ per pulse within a 100 mrad angle, and that increasing the transverse plasma size and electron beam energy could provide more than 100 muj/pulse.

  20. PARTS: (Plasma Accelerated Reusable Transport System)

    NASA Astrophysics Data System (ADS)

    Aherne, Michael; Davis, Phil; England, Matt; Gustavsson, Jake; Pankow, Steve; Sampaio, Chere; Savella, Phil

    2002-01-01

    The Plasma Accelerated Reusable Transport System (PARTS) is an unmanned cargo shuttle intended to ferry large payloads to and from Martian orbit using a highly efficient VAriable Specific Impulse Magnetoplasma Rocket (VASIMR). The design of PARTS focuses on balancing cost and minimizing transit time for a chosen payload consisting of vehicles, satellites, and other components provided by interested parties.

  1. Enhancement of electron energy during vacuum laser acceleration in an inhomogeneous magnetic field

    SciTech Connect

    Saberi, H.; Maraghechi, B.

    2015-03-15

    In this paper, the effect of a stationary inhomogeneous magnetic field on the electron acceleration by a high intensity Gaussian laser pulse is investigated. A focused TEM (0,0) laser mode with linear polarization in the transverse x-direction that propagates along the z-axis is considered. The magnetic field is assumed to be stationary in time, but varies longitudinally in space. A linear spatial profile for the magnetic field is adopted. In other words, the axial magnetic field increases linearly in the z-direction up to an optimum point z{sub m} and then becomes constant with magnitude equal to that at z{sub m}. Three-dimensional single-particle simulations are performed to find the energy and trajectory of the electron. The electron rotates around and stays near the z-axis. It is shown that with a proper choice of the magnetic field parameters, the electron will be trapped at the focus of the laser pulse. Because of the cyclotron resonance, the electron receives enough energy from the laser fields to be accelerated to relativistic energies. Using numerical simulations, the criteria for optimum regime of the acceleration mechanism is found. With the optimized parameters, an electron initially at rest located at the origin achieves final energy of γ=802. The dynamics of a distribution of off-axis electrons are also investigated in which shows that high energy electrons with small energy and spatial spread can be obtained.

  2. Requirements and guidelines for NSLS experimental beam line vacuum systems: Revision A

    SciTech Connect

    Foerster, C.; Halama, H.; Thomlinson, W.

    1986-10-01

    Requirements are provided for NSLS beam line front ends and vacuum interlocks. Guidelines are provided for UHV beam line vacuum systems, including materials, vacuum hardware (pumps, valves, and flanges), acoustic delay lines and beam line fast valves, instrumentation, fabrication and testing, and the NSLS cleaning facility. Also discussed are the design review for experimenters' equipment that would be connected to the NSLS and acceptance tests for any beam line to be connected with the ring vacuum. Also appended are a description of the acoustic delay line as well as the NSLS vacuum standards and NSLS procedures. (LEW)

  3. Vacuum system design for the PEP-II B Factory High-Energy Ring

    SciTech Connect

    Perkins, C.; Bostic, D.; Daly, E.

    1994-06-01

    The design of the vacuum system for the PEP-II B Factory High-Energy Ring is reviewed. The thermal design and vacuum requirements are particularly challenging in PEP-II due to high stored beam currents up to 3.0 amps in 1658 bunches. The vacuum chambers for the HER arcs are fabricated by electron beam welding extruded copper sections up to 6 m long. Design of these chambers and the vacuum PumPing configuration is described with results from vacuum and thermal analyses.

  4. Caps Seal Boltholes On Vacuum-System Flanges

    NASA Technical Reports Server (NTRS)

    Roman, Robert F.

    1993-01-01

    Sealing caps devised for boltholes on vacuum-system flanges. Used in place of leak-prone gaskets, and provide solid metal-to-metal interfaces. Each sealing cap contains square-cut circular groove in which O-ring placed. Mounted on studs protruding into access ports, providing positive seal around each bolthole. Each cap mates directly with surface of flange, in solid metal-to-metal fit, with O-ring completely captured in groove. Assembly immune to misalignment, leakage caused by vibration, and creeping distortion caused by weight of port. O-ring material chosen for resistance to high temperature; with appropriate choice of material, temperature raised to as much as 315 degrees C.

  5. X-ray lithography source (SXLS) vacuum system

    SciTech Connect

    Schuchman, J.C.; Aloia, J.; Hsieh, H.; Kim, T.; Pjerov, S.

    1989-01-01

    In 1988 Brookhaven National Laboratory (BNL) was awarded a contract to design and construct a compact light source for x-ray lithography. This award is part of a technology transfer-to-American-industry program. The contract is for an electron storage ring designed for 690 MeV-500 ma operations. It has a racetrack configuration with a circumference to 8.5 meters. The machine is to be constructed in two phases. Phase I (200 MeV-500ma) will primarily be for low energy injection studies and will incorporate all room temperature magnets. For Phase II the two room temperature dipole magnets will be replaced with (4T) superconducting magnets and operation will be at 690 MeV. This paper describes the vacuum system for this machine. 9 refs.

  6. LCLS XTOD Tunnel Vacuum Transport System (XVTS) Final Design Report

    SciTech Connect

    Shen, S

    2006-10-16

    The design of the X-Ray Vacuum Transport System (XVTS) for the Linac Coherent Light Source (LCLS) X-ray Transport, Optics and Diagnostics (XTOD) system has been analyzed and configured by the Lawrence Livermore National Laboratory's New Technologies Engineering Division (NTED) as requested by the SLAC/LCLS program. A preliminary design review was held on 11/14/05 [1][2]. This FDR (Final Design Report) presents system configuration, detailed analyses and selection of the mechanical and electrical components for the XTOD tunnel section, as well as the response to all issues raised in the review committee report. Also included are the plans for procurement, mechanical integration, schedule and the cost estimates. It should be noticed that, after the XVTS PDR, LCLS management has decided to lower the number of beamlines from three to one, and shorten the tunnel length from 212 m to 184 m. [3][4] The final design of XVTS system is completed. The major subjects presented in this report are: (1) Design of the complete system. (2) System analysis results. (3) ES&H issues and plan. (4) Project cost estimates and schedule.

  7. Acceleration by pulsar winds in binary systems

    NASA Technical Reports Server (NTRS)

    Harding, Alice K.; Gaisser, T. K.

    1990-01-01

    In the absence of accretion torques, a pulsar in a binary system will spin down due to electromagnetic dipole radiation and the spin-down power will drive a wind of relativistic electron-positron pairs. Winds from pulsars with short periods will prevent any subsequent accretion but may be confined by the companion star atmosphere, wind, or magnetosphere to form a standing shock. The authors investigate the possibility of particle acceleration at such a pulsar wind shock and the production of very high energy (VHE) and ultra high energy (UHE) gamma rays from interactions of accelerated protons in the companion star's wind or atmosphere. They find that in close binaries containing active pulsars, protons will be shock accelerated to a maximum energy dependent on the pulsar spin-down luminosity. If a significant fraction of the spin-down power goes into particle acceleration, these systems should be sources of VHE and possibly UHE gamma rays. The authors discuss the application of the pulsar wind model to binary sources such as Cygnus X-3, as well as the possibility of observing VHE gamma-rays from known binary radio pulsar systems.

  8. Acceleration by pulsar winds in binary systems

    NASA Technical Reports Server (NTRS)

    Harding, Alice K.; Gaisser, T. K.

    1990-01-01

    In the absence of accretion torques, a pulsar in a binary system will spin down due to electromagnetic dipole radiation, and the spin-down power will drive a wind of relativistic electron-position pairs. Winds from pulsars with short periods will prevent any subsequent accretion but may be confined by the companion star atmosphere, wind, or magnetosphere to form a standing shock. This paper investigates the possibility of particle acceleration at such a pulsar wind shock and the production of VHE and UHE gamma-rays from interactions of accelerated protons in the companion star's wind or atmosphere. It is found that, in close binaries containing active pulsars, protons will be shock accelerated to a maximum energy dependent on the pulsar spin-down luminosity. If a significant fraction of the spin-down power goes into particle acceleration, these systems should be sources of VHE and possibly UHE gamma-rays. The application of the pulsar wind model to binary sources such as Cygnus X-3 is discussed, as well as the possibility of observing VHE gamma-rays from known binary radio pulsar systems.

  9. BNL ACCELERATOR TEST FACILITY CONTROL SYSTEM UPGRADE.

    SciTech Connect

    MALONE,R.; BEN-ZVI,I.; WANG,X.; YAKIMENKO,V.

    2001-06-18

    Brookhaven National Laboratory's Accelerator Test Facility (ATF) has embarked on a complete upgrade of its decade old computer system. The planned improvements affect every major component: processors (Intel Pentium replaces VAXes), operating system (Linux/Real-Time Linux supplants OpenVMS), and data acquisition equipment (fast Ethernet equipment replaces CAMAC serial highway.) This paper summarizes the strategies and progress of the upgrade along with plans for future expansion.

  10. Induction accelerators for the phase rotator system

    SciTech Connect

    Reginato, Lou; Yu, Simon; Vanecek, Dave

    2001-07-30

    The principle of magnetic induction has been applied to the acceleration of high current beams in betatrons and a variety of induction accelerators. The linear induction accelerator (LIA) consists of a simple nonresonant structure where the drive voltage is applied to an axially symmetric gap that encloses a toroidal ferromagnetic material. The change in flux in the magnetic core induces an axial electric field that provides particle acceleration. This simple nonresonant (low Q) structure acts as a single turn transformer that can accelerate from hundreds of amperes to tens of kiloamperes, basically only limited by the drive impedance. The LIA is typically a low gradient structure that can provide acceleration fields of varying shapes and time durations from tens of nanoseconds to several microseconds. The efficiency of the LIA depends on the beam current and can exceed 50% if the beam current exceeds the magnetization current required by the ferromagnetic material. The acceleration voltage available is simply given by the expression V=A dB/dt. Hence, for a given cross section of material, the beam pulse duration influences the energy gain. Furthermore, a premium is put on minimizing the diameter, which impacts the total weight or cost of the magnetic material. The diameter doubly impacts the cost of the LIA since the power (cost) to drive the cores is proportional to the volume as well. The waveform requirements during the beam pulse makes it necessary to make provisions in the pulsing system to maintain the desired dB/dt during the useful part of the acceleration cycle. This is typically done two ways, by using the final stage of the pulse forming network (PFN) and by the pulse compensation network usually in close proximity of the acceleration cell. The choice of magnetic materials will be made by testing various materials both ferromagnetic and ferrimagnetic. These materials will include the nickel-iron, silicon steel amorphous and various types of ferrites not

  11. The Formalism for Energy Changing Rate of an Accelerated Atom Coupled with Electromagnetic Vacuum Fluctuations

    NASA Astrophysics Data System (ADS)

    Zhang, Anwei

    2016-05-01

    The structure of the rate of variation of the atomic energy for an arbitrary stationary motion of the atom in interaction with a quantum electromagnetic field is investigated. Our main purpose is to rewrite the formalism in Zhu et al. (Phys Rev D 73:107501, 2006) and to deduce the general expressions of the Einstein A coefficients of an atom on an arbitrary stationary trajectory. The total rate of change of the energy and Einstein coefficients of the atom near a plate with finite temperature or acceleration are also investigated.

  12. Ion acceleration - A phenomenon characteristic of the 'expansion of plasma into a vacuum'

    NASA Technical Reports Server (NTRS)

    Samir, Uri; Wright, K. H., Jr.; Stone, N. H.

    1986-01-01

    The physics of the complex process by which plasma expands across a strong density gradient is briefly discussed with particular emphasis on the resulting ion acceleration. The results from a laboratory experiment that addresses the steady-state expansion of a collisionless, streaming plasma into the wake of a body are presented. The experimental results are in good qualitative agreement with theoretical predictions, thereby demonstrating the equivalence of expansion with distance in the flow direction to time in the one-dimensional theory. On this basis, the potential application of the plasma process in space plasma physics is mentioned.

  13. High current RF shield for PEP-II vacuum system expansion joint

    SciTech Connect

    Belser, F.C.; Berg, J.D.; Kerns, J.

    1996-05-01

    A novel RF shield was developed for the circular expansion joint used throughout the PEP-II vacuum system straight sections. Existing RF shield designs, used in accelerators/storage rings throughout the world, have been the source of many failures at beam currents much smaller than the 3 amps planned for PEP-II. This RF shield uses a unique spring-loaded finger mechanism to maintain proper electrical contact across the joint, accommodate 1.5 mm transverse and 32 mm longitudinal excursions, while minimizing geometry-driven trapped-mode RF heating at GHz frequencies. Alumina-dispersed, copper alloy fingers are used to maintain desired mechanical properties at higher temperatures instead of the more commonly used beryllium-copper alloys. A prototype expansion joint was assembled, mechanically tested, and subjected to 200% of the expected operational RF load. This RF shield design can be easily adapted to non-circular geometries.

  14. Experimental study of the reduction of field emission by gas injection in vacuum for accelerator applications

    NASA Astrophysics Data System (ADS)

    Almaksour, K.; Kirkpatrick, M. J.; Dessante, Ph.; Odic, E.; Simonin, A.; de Esch, H. P. L.; Lepetit, B.; Alamarguy, D.; Bayle, F.; Teste, Ph.

    2014-10-01

    Field emission current from surfaces under vacuum and at high field strengths can be reduced by the injection of gas into the evacuated volume. In this paper, the effects of H2, He, N2, and Ar on this "dark" current emitted from a tungsten carbide point cathode for 2 cm gap distance is studied. Exposure to any of these gases at pressures on the order of 10-3-10-2 Pa was found to reduce the emission current by up to 90% with a time constant on the order of ˜1 minute as compared to the current at 10-6 Pa. The effect was strongly dependent on the gas nature, with Ar and N2 having larger effects at lower pressures than He and H2. The reduction was reversible, with the current increasing to near its original value with a time constant on the order of ˜1-10 minutes after pumping down. The effect of the gas remained in the absence of electric field, whatever the gas pressure. Mechanisms for these and related phenomena are discussed.

  15. JV Task 59-Demonstration of Accelerated In Situ Contaminant Degradation by Vacuum-Enhanced Nutrient Distribution

    SciTech Connect

    Jaroslav Solc

    2007-03-15

    The Energy & Environmental Research Center (EERC) conducted remediation of hydrocarbon-contaminated soils and groundwater at a former Mohler Oil site in Bismarck, North Dakota. The remedial strategy was based on the application of two innovative concepts: (1) design and deployment of the mobile extraction, treatment, and injection units to overcome site limitations associated with urban settings in high-traffic areas and (2) vacuum-controlled nutrient injection within and on the periphery of an induced hydraulic and pneumatic depression. Combined contaminant recovery since the beginning of the project in June 2003 totals over 13,600 lb ({approx}6,170 kg) of hydrocarbons, equivalent to 2176 gallons (8236 l) of product. In situ delivery of 1504 Ib (682 kg) of ionic nitrate and 540 Ib (245 kg) of dissolved oxygen translates into further reduction of about 489 Ib (222 kg) of benzene for the same period and provides for long-term stimulation of the natural attenuation process. In addition to contaminant recovered by extraction and reduced by in situ biodegradation, a total of 4136 Ib (1876 kg) of oxygen was delivered to the saturated zone, resulting in further in situ reduction of an estimated 1324 lb (600 kg) of dissolved-phase hydrocarbons. Based on the results of the EERC demonstration, the North Dakota Department of Health approved site abandonment and termination of the corrective action.

  16. Acceleration of electrons by a laser pulse at its output onto an optical surface of the vacuum – transparent medium interface. Laser synchrotron

    NASA Astrophysics Data System (ADS)

    Romanovskiy, M. Yu

    2016-05-01

    We consider the electron dynamics in the field of an electromagnetic wave produced at the vacuum – transparent medium interface upon reflection from the boundary, close to total internal reflection. The propagation velocity of a constant phase of the electromagnetic wave along the interface can vary from c/n to infinity (c is the speed of light in vacuum, and n is the refractive index of the medium at the interface). In this case, there emerge regions of positive and negative phases of the field with wavelengths, approximately equal to half the wavelength of the original laser beam, which can propagate at a speed close to that of light in vacuum. If a beam of relativistic electrons propagates along the surface, they can gain energy and accelerate, as well as radiate. With closed trajectories of electron motion, a laser synchrotron will be implemented as a result of many acceleration cycles.

  17. Sewerage force adjustment technology for energy conservation in vacuum sanitation systems

    NASA Astrophysics Data System (ADS)

    Guo, Zhonghua; Li, Xiaoning; Kagawa, Toshiharu

    2013-03-01

    The vacuum sanitation is the safe and sound disposal approach of human excreta under the specific environments like flights, high speed trains and submarines. However, the propulsive force of current systems is not adjustable and the energy consumption does not adapt to the real time sewerage requirement. Therefore, it is important to study the sewerage force adjustment to improve the energy efficiency. This paper proposes an energy conservation design in vacuum sanitation systems with pneumatic ejector circuits. The sewerage force is controlled by changing the systematic vacuum degree according to the amount of the excreta. In particular, the amount of the excreta is tested by liquid level sensor and mass sensor. According to the amount of the excreta, the relationship between the excreta amount and the sewerage force is studied to provide proper propulsive force. In the other aspect, to provide variable vacuum degrees for different sanitation requirements, the suction and discharge system is designed with pneumatic vacuum ejector. On the basis of the static flow-rate characteristics and the vacuum generation model, the pressure response in the ejector circuit is studied by using the static flow rate characteristics of the ejector and air status equation. The relationship is obtained between supplied compressed air and systematic vacuum degree. When the compressed air is supplied to the ejector continuously, the systematic vacuum degree increases until the vacuum degree reaches the extreme value. Therefore, the variable systematic vacuum degree is obtained by controlling the compressed air supply of the ejector. To verify the effect of energy conservation, experiments are carried out in the artificial excreta collection, and the variable vacuum-degree design saves more than 30% of the energy supply. The energy conservation is realized effectively in the new vacuum sanitation systems with good application prospect. The proposed technology provides technological

  18. Control system for the NBS microtron accelerator

    NASA Astrophysics Data System (ADS)

    Martin, E. Ray; Trout, Robert E.; Wilson, Bonnie L.; Ayres, Robert L.; Yoder, Neil R.

    1986-06-01

    As various subsystems of the National Bureau of Standards/Los Alamos racetrack microtron accelerator are being brought on-line, experience has been gained with some of the innovations implemented in the control system. Foremost among these are the joystick-based operator controls, the hierarchical distribution of control system intelligence, and the independent secondary stations, permitting sectional stand-alone operation. The result of the distributed database philosophy and parallel data links has been very fast data updates, permitting joystick interaction with system elements. The software development was greatly simplified by using the hardware arbitration of several parallel processors in the Multibus system to split the software tasks into independent modules.

  19. Cold Vacuum Drying facility sanitary sewage collection system design description (SYS 27)

    SciTech Connect

    PITKOFF, C.C.

    1999-07-02

    This document describes the Cold Vacuum Drying Facility (CVDF) sanitary sewage collection system. The sanitary sewage collection system provides collection and storage of effluents and raw sewage from the CVDF to support the cold vacuum drying process. This system is comprised of a sanitary sewage holding tank and pipes for collection and transport of effluents to the sanitary sewage holding tank.

  20. Accelerating Science Driven System Design With RAMP

    SciTech Connect

    Wawrzynek, John

    2015-05-01

    Researchers from UC Berkeley, in collaboration with the Lawrence Berkeley National Lab, are engaged in developing an Infrastructure for Synthesis with Integrated Simulation (ISIS). The ISIS Project was a cooperative effort for “application-driven hardware design” that engages application scientists in the early parts of the hardware design process for future generation supercomputing systems. This project served to foster development of computing systems that are better tuned to the application requirements of demanding scientific applications and result in more cost-effective and efficient HPC system designs. In order to overcome long conventional design-cycle times, we leveraged reconfigurable devices to aid in the design of high-efficiency systems, including conventional multi- and many-core systems. The resulting system emulation/prototyping environment, in conjunction with the appropriate intermediate abstractions, provided both a convenient user programming experience and retained flexibility, and thus efficiency, of a reconfigurable platform. We initially targeted the Berkeley RAMP system (Research Accelerator for Multiple Processors) as that hardware emulation environment to facilitate and ultimately accelerate the iterative process of science-driven system design. Our goal was to develop and demonstrate a design methodology for domain-optimized computer system architectures. The tangible outcome is a methodology and tools for rapid prototyping and design-space exploration, leading to highly optimized and efficient HPC systems.

  1. An automated thermal vacuum test system for use in environmental testing of flight systems and components

    NASA Technical Reports Server (NTRS)

    Cleckner, Craig S.; Knutson, Jeffrey R.

    1991-01-01

    Unusual requirements for the Pressure Distribution/Air Data System (PD/ADS) transducer thermal vacuum testing led to the development of a conductively heated and cooled, fully automated, bell-jar test system. The system has proven to be easily adaptable for other tests and offers the advantages of quick turn-around and low operational cost.

  2. Fermilab tevatron high level RF accelerating systems

    SciTech Connect

    Kerns, Q.; Kerns, C.; Miller, H.; Reid, J.; Tawzer, S.; Webber, R.; Wildman, D.

    1985-10-01

    Eight tuned rf cavities have been installed and operated in the F0 straight section of the Tevatron. Their mechanical placement along the beam line enables them to be operated for colliding beams as two independent groups of four cavities, group 1-4 accelerating antiprotons and group 5-8 accelerating protons. The only difference is that the spacing between cavities 4 and 5 was increased to stay clear of the F0 colliding point. The cavities can easily be rephased by switching cables in a low-level distribution system (fan-out) so that the full accelerating capability of all eight cavities can be used during fixed target operations. Likewise, the cables from capacitive probes on each cavity gap can be switched to proper lengths and summed in a fan-back system to give an rf signal representing the amplitude and phase as ''seen by the beam,'' separately for protons and antiprotons. Such signals have been used to phase lock the Tevatron to the Main Ring for synchronous transfer. A cavity consists of two quarter-wave resonators placed back to back with a coaxial drift tube separating the two accelerating gaps by ..pi.. radians. The cavities are very similar to the prototype which has been previously described/sup 3/ and is operating as Station 8 in the Tevatron. Only additional water cooling around the high current region of the drift tube supports and a double loop used to monitor the unbalance current through the Hipernom mode damping resistor have been added. Each cavity has a Q of about7100, a shunt impedance of 1.2 M..cap omega.., and is capable of running cw with a peak accelerating voltage of 360

  3. Accelerated degradation of silicon metallization systems

    NASA Technical Reports Server (NTRS)

    Lathrop, J. W.

    1983-01-01

    Clemson University has been engaged for the past five years in a program to determine the reliability attributes of solar cells by means of accelerated test procedures. The cells are electrically measured and visually inspected and then subjected for a period of time to stress in excess of that normally encountered in use, and then they are reinspected. Changes are noted and the process repeated. This testing has thus far involved 23 different unencapsulated cell types from 12 different manufacturers, and 10 different encapsulated cell types from 9 different manufacturers. Reliability attributes of metallization systems can be classified as major or minor, depending on the severity of the effects observed. As a result of the accelerated testing conducted under the Clemson program, major effects have been observed related to contact resistance and to mechanical adherence and solderability. This paper does not attempt a generalized survey of accelerated test results, but rather concentrates on one particular attribute of metallization that has been observed to cause electrical degradation - increased contact resistance due to Schottky barrier formation. In this example basic semiconductor theory was able to provide an understanding of the electrical effects observed during accelerated stress testing.

  4. Pulsed power systems for the DARHT accelerators

    SciTech Connect

    Downing, J.N.; Parsons, W.M.; Earley, L.M.; Melton, J.G.; Moir, D.C.; Carlson, R.L.; Barnes, G.A.; Builta, L.A.; Eversole, S.A.; Keel, G.I.; Rader, D.C.; Romero, J.A.; Shurter, R.P.

    1991-01-01

    The Dual-Axis Radiographic Hydro Test (DARHT) Facility is being designed to produce high-resolution flash radiographs of hydrodynamics experiments. Two 16- to 20-MeV linear induction accelerators (LIA), with an included angle of 90{degree}, are used to produce intense bremsstrahlung x-ray pulses of short duration (60-ns flat-top). Each accelerator has a 4-MeV electron source that injects an electron beam into a series of 250-kV induction cells. The three major pulsed-power systems are the injectors, the induction-cell pulsed-power (ICPP) units, and the ICPP trigger systems, and are discussed in this paper. 11 refs., 5 figs, 3 tabs.

  5. Design and test results of the Low Energy Demonstration Accelerator (LEDA) RF systems

    SciTech Connect

    Rees, D.; Bradley, J. III; Cummings, K.; Lynch, M.; Regan, A.; Rohlev, T.; Roybal, W.; Wang, Y.M.

    1998-12-01

    The Low Energy Demonstration Accelerator (LEDA) being constructed at Los Alamos will serve as the prototype for the low energy section of the Accelerator Production of Tritium (APT) accelerator. The APT accelerator requires over 200 RF systems each with a continuous wave output power of 1 MW. The reliability and availability of these RF systems is critical to the successful operation of the APT plant and prototypes of these systems are being developed and demonstrated on LEDA. The RF system design for LEDA includes three, 1.2 MW, 350 MHz continuous wave (CW), RF systems driving a radio frequency quadrupole (RFQ) and one, 1.0 MW, CW, RF system driving a coupled-cavity drift tube linac (CCDTL). This paper presents the design and test results for these RF systems including the klystrons, cathode power supply, circulators, RF vacuum windows, accelerator field and resonance control system, and RF transmission components. The three RF systems driving the RFQ use the accelerating structure as a power combiner, and this places some unique requirements on the RF system. These requirements and corresponding operational implications will be discussed.

  6. Railgun power supply system utilizing traction motors and vacuum interrupters

    SciTech Connect

    Parsons, W.M.; Parker, J.V.; Thullen, P.

    1985-01-01

    A railgun power supply has been designed that utilizes traction motors, vacuum interrupters and pulse transformers. An assembly of 28 traction motors, which store approximately 75 MJ, energize the primary windings of three pulse transformers at a peak current of 50 kA. At peak current an array of vacuum interrupters disconnects the transformer primary windings and forces the current to flow in the secondary windings. The secondary windings are connected directly to the railgun and require no opening switches. By staging the vacuum interrupter openings, a 1 MA to 1.3 MA ramped current waveform can be delivered to the railgun.

  7. Fermilab Tevatron high level rf accelerating systems

    SciTech Connect

    Kerns, Q.; Kerns, C.; Miller, H.; Tawser, S.; Reid, J.; Webber, R.; Wildman, D.

    1985-06-01

    Eight tuned rf cavities have been installed and operated in the F0 straight section of the Tevatron. Their mechanical placement along the beam line enables them to be operated for colliding beams as two independent groups of four cavities, group 1-4 accelerating antiprotons and group 5-8 accelerating protons. The only difference is that the spacing between cavities 4 and 5 was increased to stay clear of the F0 colliding point. The cavities can easily be rephased by switching cables in a low-level distribution system (fan-out) so that the full accelerating capability of all eight cavities can be used during fixed target operations. Likewise, the cables from capacitive probes on each cavity gap can be switched to proper lengths and summed in a fan-back system to give an rf signal representing the amplitude and phase as ''seen by the beam,'' separately for protons and antiprotons. Such signals have been used to phase lock the Tevatron to the Main Ring for synchronous transfer.

  8. Final design and status of the NSLS vacuum system

    SciTech Connect

    Schuchman, J.C.

    1982-01-01

    We describe the final system, as built, reasons for changes and the general status of the NSLS. The NSLS is a dedicated facility for the purpose of producing synchrotron radiation. It consists of an electron linac-booster injector system, and two storage rings, one for uv research and the other for x-ray research. (Synchrotron radiation is produced by accelerating electrons in the storage rings.) The design current and energies are 1000 ma at 700 MeV for the vuv ring and 500 ma at 2.5 GeV for the x-ray ring. A total of 44 experimental beam ports are available for use. Since each beam port may be divided into two or more experimentall beam lines, it is quite plausible to have upward of 100 simultaneously operating beam lines.

  9. Open Hardware for CERN's accelerator control systems

    NASA Astrophysics Data System (ADS)

    van der Bij, E.; Serrano, J.; Wlostowski, T.; Cattin, M.; Gousiou, E.; Alvarez Sanchez, P.; Boccardi, A.; Voumard, N.; Penacoba, G.

    2012-01-01

    The accelerator control systems at CERN will be upgraded and many electronics modules such as analog and digital I/O, level converters and repeaters, serial links and timing modules are being redesigned. The new developments are based on the FPGA Mezzanine Card, PCI Express and VME64x standards while the Wishbone specification is used as a system on a chip bus. To attract partners, the projects are developed in an `Open' fashion. Within this Open Hardware project new ways of working with industry are being evaluated and it has been proven that industry can be involved at all stages, from design to production and support.

  10. Variable Acceleration Force Calibration System (VACS)

    NASA Technical Reports Server (NTRS)

    Rhew, Ray D.; Parker, Peter A.; Johnson, Thomas H.; Landman, Drew

    2014-01-01

    Conventionally, force balances have been calibrated manually, using a complex system of free hanging precision weights, bell cranks, and/or other mechanical components. Conventional methods may provide sufficient accuracy in some instances, but are often quite complex and labor-intensive, requiring three to four man-weeks to complete each full calibration. To ensure accuracy, gravity-based loading is typically utilized. However, this often causes difficulty when applying loads in three simultaneous, orthogonal axes. A complex system of levers, cranks, and cables must be used, introducing increased sources of systematic error, and significantly increasing the time and labor intensity required to complete the calibration. One aspect of the VACS is a method wherein the mass utilized for calibration is held constant, and the acceleration is changed to thereby generate relatively large forces with relatively small test masses. Multiple forces can be applied to a force balance without changing the test mass, and dynamic forces can be applied by rotation or oscillating acceleration. If rotational motion is utilized, a mass is rigidly attached to a force balance, and the mass is exposed to a rotational field. A large force can be applied by utilizing a large rotational velocity. A centrifuge or rotating table can be used to create the rotational field, and fixtures can be utilized to position the force balance. The acceleration may also be linear. For example, a table that moves linearly and accelerates in a sinusoidal manner may also be utilized. The test mass does not have to move in a path that is parallel to the ground, and no re-leveling is therefore required. Balance deflection corrections may be applied passively by monitoring the orientation of the force balance with a three-axis accelerometer package. Deflections are measured during each test run, and adjustments with respect to the true applied load can be made during the post-processing stage. This paper will

  11. VecLoader HEPA Vacuum Insulation Removal System

    SciTech Connect

    None, None

    1999-09-01

    The United States Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the deactivation and decommissioning (D&D) of nuclear facilities. To this end, the Deactivation and Decommissioning Focus Area (DDFA) of the DOE’s Office of Science and Technology sponsors Large-Scale Demonstration Projects (LSDPs) at which developers and vendors of improved or innovative technologies showcase products that are potentially beneficial to DOE’s projects and to others in the D&D community. Benefits sought include decreased health and safety risks to personnel and the environment, increased productivity, decreased costs and shortened schedules. The U.S. Department of Energy (DOE) Fernald Environmental Management Project’s (FEMP’s) Decontamination and Decommissioning (D&D) Plan requires that interior and exterior walls of buildings that are being demolished be disassembled and all insulating materials removed prior to demolition. This report provides a comparative analysis of the baseline manual insulation removal technique currently employed at the FEMP, with an innovative vacuum insulation removal system.

  12. Gas distribution through injection manifolds in vacuum systems

    NASA Astrophysics Data System (ADS)

    Theil, Jeremy A.

    1995-03-01

    When injecting gas into a vacuum system, quite often the gas is distributed through a gas injection manifold. However, designs normally rely upon practical experience. By considering the manifold arrangement as a network of flow restrictions it is possible to optimize the distribution of gas throughout the manifold. The methodology for determining the flow distribution through the two simplest topologies of gas manifold, single- and double-opening manifolds from a single-gas injection point, is derived in this article. It is shown that the double-opening manifold topology tends to provide more uniform flow distribution than the single-opening manifold topology for similar conductance ratios. The results of this work include a summation formula for the single-opening manifold. In addition, guidelines for one type of tailored flow manifold are given. Finally, three basic design rules are presented: (1) use as few holes in the manifold as possible; (2) use a double opening manifold when possible; and (3) specify tube dimensions such that the tube/spray hole conductance ratio is maximized.

  13. NSLS vacuum system operating experience conditioning and desorption yields

    SciTech Connect

    Halama, H.J.

    1991-01-01

    All straight sections in both the VUV and the X-Ray rings have been filled with various insertion devices, most of them fully operational. Beam lifetime in the VUV ring is limited by the Touschek effect to {approximately}100 minutes at 800 mA due to the small vertical beam size required by users. With no experiments running, X-Ray beam lifetime is >35 hours at 220 mA and is limited by beam gas scattering. During the past several years the U10 beam line was used to measure PSD yields from various metals to study their relative merits for light sources. These yields were also compared to those measured in X-Ray ring dipoles during initial commissioning when desorption was high. Despite the large differences in critical photon energies, agreement was quite good. Both rings are now fully conditioned and their pressures and lifetimes have reached equilibrium. Well established conditioning procedures are followed after every intervention into their vacuum systems.

  14. Space Acceleration Measurement System for Free Flyers

    NASA Technical Reports Server (NTRS)

    Kacpura, Thomas J.

    1999-01-01

    Experimenters from the fluids, combustion, materials, and life science disciplines all use the microgravity environment of space to enhance their understanding of fundamental physical phenomena caused by disturbances from events such as spacecraft maneuvers, equipment operations, atmospheric drag, and (for manned flights) crew movement. Space conditions reduce gravity but do not eliminate it. To quantify the level of these disturbances, NASA developed the Space Acceleration Measurement System (SAMS) series to collect data characterizing the acceleration environment on the space shuttles. This information is provided to investigators so that they can evaluate how the microgravity environment affects their experiments. Knowledge of the microgravity environment also helps investigators to plan future experiments. The original SAMS system flew 20 missions on the shuttle as well as on the Russian space station Mir. Presently, Lewis is developing SAMS-II for the International Space Station; it will be a distributed system using digital output sensor heads. The latest operational version of SAMS, SAMS-FF, was originally designed for free flyer spacecraft and unmanned areas. SAMS-FF is a flexible, modular system, housed in a lightweight package, and it uses advances in technology to improve performance. The hardware package consists of a control and data acquisition module, three different types of sensors, data storage devices, and ground support equipment interfaces. Three different types of sensors are incorporated to measure both high- and low-frequency accelerations and the roll rate velocity. Small, low-power triaxial sensor heads (TSH's) offer high resolution and selectable bandwidth, and a special low-frequency accelerometer is available for high-resolution, low-frequency applications. A state-of-the-art, triaxial fiberoptic gyroscope that measures extremely low roll rates is housed in a compact package. The versatility of the SAMS-FF system is shown in the three

  15. Uncertainty assessment for accelerator-driven systems.

    SciTech Connect

    Finck, P. J.; Gomes, I.; Micklich, B.; Palmiotti, G.

    1999-06-10

    The concept of a subcritical system driven by an external source of neutrons provided by an accelerator ADS (Accelerator Driver System) has been recently revived and is becoming more popular in the world technical community with active programs in Europe, Russia, Japan, and the U.S. A general consensus has been reached in adopting for the subcritical component a fast spectrum liquid metal cooled configuration. Both a lead-bismuth eutectic, sodium and gas are being considered as a coolant; each has advantages and disadvantages. The major expected advantage is that subcriticality avoids reactivity induced transients. The potentially large subcriticality margin also should allow for the introduction of very significant quantities of waste products (minor Actinides and Fission Products) which negatively impact the safety characteristics of standard cores. In the U.S. these arguments are the basis for the development of the Accelerator Transmutation of Waste (ATW), which has significant potential in reducing nuclear waste levels. Up to now, neutronic calculations have not attached uncertainties on the values of the main nuclear integral parameters that characterize the system. Many of these parameters (e.g., degree of subcriticality) are crucial to demonstrate the validity and feasibility of this concept. In this paper we will consider uncertainties related to nuclear data only. The present knowledge of the cross sections of many isotopes that are not usually utilized in existing reactors (like Bi, Pb-207, Pb-208, and also Minor Actinides and Fission Products) suggests that uncertainties in the integral parameters will be significantly larger than for conventional reactor systems, and this raises concerns on the neutronic performance of those systems.

  16. Upgrade of The Thermal Vacuum Data System at NASA/GSFC

    NASA Technical Reports Server (NTRS)

    Palmer, John; Powers, Edward I. (Technical Monitor)

    2000-01-01

    The Goddard Space Flight Center's new thermal vacuum data acquisition system is a networked client-sever application that enables lab operations crews to monitor all tests from a central location. The GSFC thermal vacuum lab consists of eleven chambers in Building 7 and one chamber in Building 10. The new data system was implemented for several reasons. These included the need for centralized data collection, more flexible and easier to use operator interface, greater data accessibility, a reduction in testing time and cost, and increased payload and personnel safety. Additionally, a new data system was needed for year-2000 compliance. This paper discusses the incorporation of the Thermal Vacuum Data System (TVDS) within the thermal vacuum lab at GSFC, its features and capabilities and lessons learned in its implementation. Additional topics include off-center (Internet) capability for remote monitoring and the role of TVDS in the efforts to automate thermal vacuum chamber operations.

  17. Upgrade of the Thermal Vacuum Data System at NASA/GSFC

    NASA Technical Reports Server (NTRS)

    Palmer, John

    2000-01-01

    The Goddard Space Flight Center's new thermal vacuum data acquisition system is a networked client-sever application that enables lab operations crews to monitor all tests from a central location. The GSFC thermal vacuum lab consists of eleven chambers in Building 7 and one chamber in Building 10. The new data system was implemented for several reasons. These included the need for centralized data collection, more flexible and easier to use operator interface, greater data accessibility, a reduction in testing time and cost, and increased payload and personnel safety. Additionally, a new data system was needed for year-2000 compliance. This paper discusses the incorporation of the Thermal Vacuum Data System (TVDS) within the thermal vacuum lab at GSFC, its features and capabilities and lessons learned in its implementation. Additional topics include off-center (Internet) capability for remote monitoring and the role of TVDS in the efforts to automate thermal vacuum chamber operations.

  18. Vacuum system design of the International Thermonuclear Experimental Reactor pellet fueling system

    SciTech Connect

    Langley, R.A.; Gouge, M.J. ); Santeler, D.J. )

    1994-07-01

    The International Thermonuclear Experimental Reactor (ITER) will use an advanced, high-velocity pellet injection system to fuel ignited plasmas. For rampup to ignition, a moderate-velocity (1--1.5 km/s) single-stage pneumatic injector and a high-velocity (1.5--5 km/s) two-stage pneumatic injector using pellets encased in sabots are envisioned. For the steady-state burn phase a continuous, single-stage pneumatic injector and a centrifugal injector are proposed. The purpose of this study is to simulate the ITER pellet injection line vacuum pumping system to determine the pump requirements. This study analyzed the injector vacuum system using commercially available vacuum pumps compatible with tritium operation. The vacuum system design program, VSD-II, was used to determine the gas flow through the system components for various pumping arrangements and component sizes and geometries. The VSD-II computer program allows changes to be made easily in the input so that results from different configurations are readily obtained and compared. Results are presented and issues in the design are discussed as well as limitations in the existing pump data.

  19. Cold Vacuum Drying (CVD) Facility Safety Class Instrumentation & Control System Design Description

    SciTech Connect

    WHITEHURST, R.

    1999-12-01

    This document describes the Cold Vacuum Drying Facility (CVDF) Safety Class Instrumentation and Control system (SCIC). The SCIC provides safety functions and features to protect the environment, off-site and on-site personnel and equipment. The function of the SCIC is to provide automatic trip features, valve interlocks, alarms, indication and control for the cold vacuum drying process.

  20. Limiter/vacuum system for plasma impurity control and exhaust in tokamaks

    SciTech Connect

    Abdou, M.; Brooks, J.; Mattas, R.

    1980-01-01

    A detailed design of a limiter/vacuum system for plasma impurity control and exhaust has been developed for the STARFIRE tokamak power plant. It is shown that the limiter/vacuum concept is a very attractive option for power reactors. It is relatively simple and inexpensive and deserves serious experimental verification.

  1. Reliable timing systems for computer controlled accelerators

    NASA Astrophysics Data System (ADS)

    Knott, Jürgen; Nettleton, Robert

    1986-06-01

    Over the past decade the use of computers has set new standards for control systems of accelerators with ever increasing complexity coupled with stringent reliability criteria. In fact, with very slow cycling machines or storage rings any erratic operation or timing pulse will cause the loss of precious particles and waste hours of time and effort of preparation. Thus, for the CERN linac and LEAR (Low Energy Antiproton Ring) timing system reliability becomes a crucial factor in the sense that all components must operate practically without fault for very long periods compared to the effective machine cycle. This has been achieved by careful selection of components and design well below thermal and electrical limits, using error detection and correction where possible, as well as developing "safe" decoding techniques for serial data trains. Further, consistent structuring had to be applied in order to obtain simple and flexible modular configurations with very few components on critical paths and to minimize the exchange of information to synchronize accelerators. In addition, this structuring allows the development of efficient strategies for on-line and off-line fault diagnostics. As a result, the timing system for Linac 2 has, so far, been operating without fault for three years, the one for LEAR more than one year since its final debugging.

  2. Accelerator-based neutron radioscopic systems

    NASA Astrophysics Data System (ADS)

    Berger, Harold; Dance, William E.

    1999-06-01

    There is interest in non-reactor source, thermal neutron inspection systems for applications in aircraft maintenance, explosive devices, investment-cast turbine blades, etc. Accelerator sources, (d-T), RFQ accelerators and cyclotrons as examples, are available for either transportable or fixed neutron inspection systems. Sources are reviewed for neutron output, portability, ease of use and cost, and for use with an electronic neutron imaging camera (image intensifier or scintillator-camera system) to provide a prompt response, neutron inspection system. Particular emphasis is given to the current aircraft inspection problem to detect and characterize corrosion. Systems are analyzed to determine usefulness in providing an on-line inspection technique to detect corrosion in aluminum honeycomb aircraft components, either on-aircraft or in a shop environment. The neutron imaging sensitivity to hydrogenous aluminum corrosion product offers early detection advantages for aircraft corrosion, to levels of aluminum metal loss as small as 25 μm. The practical capability for a continuous scan thermal neutron radioscopic system to inspect up to 500 square feet of component surface per day is used as an evaluation criterion, with the system showing contrast sensitivity of at least 5% and image detail in the order of 4 mm for parts 10 cm thick. Under these practical conditions and 3-shift operation, the source must provide an incident thermal neutron flux of 5.6×104n cm-2 s-1 at an L/D of 30. A stop and go inspection approach, offering improved resolution, would require a source with similar characteristics.

  3. Critical Systems Engineering Accelerator: Aerospace Demonstrator

    NASA Astrophysics Data System (ADS)

    Moreno, Ricardo; Fernandez, Gonzalo; Regada, Raul; Basanta, Luis; Alana, Elena; Del Carmen Lomba, Maria

    2014-08-01

    Nowadays, the complexity and functionality of space systems is increasing more and more. Safety critical systems have to guarantee strong safety and dependability constraints. This paper presents CRYSTAL (Critical sYSTem engineering AcceLeration), a cross-domain ARTEMIS project for increasing the efficiency of the embedded software development in the industry through the definition of an integrated tool chain. CRYSTAL involves four major application domains: Aerospace, Automotive, Rail and Medical Healthcare. The impact in the Space Domain will be evaluated through a demonstrator implemented using CRYSTAL framework: the Low Level Software for an Avionics Control Unit, capable to run Application SW for autonomous navigation, image acquisition control, data compression and/or data handling. Finally, the results achieved will be evaluated taking into account the ECSS (European Committee for Space Standardization) standards and procedures.

  4. VACUUM TRAP

    DOEpatents

    Gordon, H.S.

    1959-09-15

    An improved adsorption vacuum trap for use in vacuum systems was designed. The distinguishing feature is the placement of a plurality of torsionally deformed metallic fins within a vacuum jacket extending from the walls to the central axis so that substantially all gas molecules pass through the jacket will impinge upon the fin surfaces. T fins are heated by direct metallic conduction, thereby ol taining a uniform temperature at the adeorbing surfaces so that essentially all of the condensible impurities from the evacuating gas are removed from the vacuum system.

  5. Review of vacuum systems for x-ray lithography light sources

    SciTech Connect

    Schuchman, J.C.

    1990-01-01

    This paper will review and give a status report on vacuum systems for X-Ray lithography light sources. It will include conventional machines and compact machines (machines using superconducting magnets). The vacuum systems will be described and compared with regard to basic machine parameters, pumping systems, types of pumps, chamber design and material, gauging and diagnostics, and machine performane. 23 refs., 8 figs., 1 tab.

  6. Temperature control system for the study of single event effects in integrated circuits using a cyclotron accelerator

    NASA Astrophysics Data System (ADS)

    Bakerenkov, A. S.; Belyakov, V. V.; Kozyukov, A. E.; Pershenkov, V. S.; Solomatin, A. V.; Shurenkov, V. V.

    2015-02-01

    The temperature control system for the study of single event disruptions produced by hard ion impacts in integrated circuits is described. Heating and cooling of the irradiated device are achieved using thermoelectric modules (Peltier modules). The thermodynamic performance of the system is estimated. The technique for the numerical estimation of the main parameters of the temperature control system for cooling and heating is considered. The results of a test of the system in a vacuum cell of an accelerator are presented.

  7. Gas species, their evolution and segregation through the ITER vacuum systems

    SciTech Connect

    Pearce, R.J.H.; Antipenkov, Alexander; Bersier, Jean-Louis; Boussier, Bastien; Baylor, Larry R; Gardner, Walter L; Meitner, Steven J

    2012-01-01

    This paper takes the ITER fueling requirements and current knowledge of gas balance and exhaust from operating tokamaks to predict all likely gas inputs into the ITER Vacuum systems. Areas where gas dynamics modeling is relevant to the ITER design are highlighted. The design and operation of the ITER vacuum system gives an element of segregation of different gas flows and species. This paper analyses the time dependent gas segregation in the vacuum system resulting from different temperature dependences of cryogenic sorption and condensation processes of different gas species. As a specific example, the optimal transfer of Ar-41 through the vacuum system is studied with respect to its decay and the resulting effects on the design of system components.

  8. Modernization of the vacuum system of synchrotron radiation sources at the National Research Centre Kurchatov Institute

    NASA Astrophysics Data System (ADS)

    Moseiko, N. I.; Krylov, Yu. V.; Moseiko, L. A.; Odintsov, D. G.; Semenov, B. I.; Shirokov, A. V.

    2012-07-01

    The modernization project of the vacuum system of the synchrotron radiation source at the National Research Centre Kurchatov Institute (NRC KI) has been designed and is being implemented; it includes a change in the system to high-voltage power sources for NMD and PVIG-0.25/630 pumps. The system is controlled via the CAN bus, and the vacuum is controlled by measuring pump currents in a range of 0.0001-10 mA. The system ensures a vacuum of 10-7 Pa. The status is mapped and the data collected into the archive are processed on the MS SQL Server platform. The efficiency and reliability of the vacuum system is increased by this work, making it possible to improve the main parameters of the SR source.

  9. Microgravity acceleration modeling for orbital systems

    NASA Technical Reports Server (NTRS)

    Knabe, Walter; Baugher, Charles R. (Editor)

    1990-01-01

    In view of the decisive importance of a disturbance-free environment on the Space Station, and on other orbital systems, for materials processing experiments, a theoretical and semi-experimental analysis of the acceleration environment to be expected on large orbiting spacecraft was undertaken. A unified model of such spacecraft cannot be established; therefore, a number of sub-models representing major components of typical large spacecraft must be investigated. In order to obtain experimental data of forces, a typical spacecraft - an engineering model of the Spacelab - was suspended on long ropes in a high-bay hangar, and equipped with a number of accelerometers. Active components on the Spacelab (fans, pumps, air conditioners, valves, levers) were operated, and astronautics moved boxes, drawers, sleds, and their own bodies. Generally speaking, the response of the Spacelab structure was very similar to the environment measured on Spacelabs SL-1, SL-2, and D-1. At frequencies in the broad range between 1 and about 100 Hz, acceleration peaks reached values of 10(exp -3) and 10(exp -2) g sub o, and even higher.

  10. The vacuum system for the PEP II high energy ring straight sections

    SciTech Connect

    Wienands, U.; Daly, E.; Kulikov, A.; Kurita, N.; Nordby, M.; Perkins, C.; Reuter, E.; Seeman, J. T.

    1995-01-01

    The six straight sections of the PEP II High Energy Ring (HER) serve various functions: lattice tuning, beam injection and abort, providing space for rf cavities, longitudinal and transverse feedback, beam diagnostics and the interaction point. A stainless steel vacuum system has been designed; prototypes are currently being built. Cooling is required due to radiation coming from the last arc dipole and resistive losses in the vacuum chamber. Although the nominal beam current of the HER is 1 A the vacuum system is designed for 3 A to provide margin and an upgrade path. 5 refs., 7 figs.

  11. The Machine Protection System for the Fermilab Accelerator Science and Technology Facility

    SciTech Connect

    Wu, Jinyuan; Warner, Arden; Liu, Ning; Neswold, Richard; Carmichael, Linden

    2015-11-15

    The Machine Protection System (MPS) for the Fermilab Accelerator Science and Technology Facility (FAST) has been implemented and tested. The system receives signals from several subsystems and devices which conveys the relevant status needed to the safely operate the accelerator. Logic decisions are made based on these inputs and some predefined user settings which in turn controls the gate signal to the laser of the photo injector. The inputs of the system have a wide variety of signal types, encoding methods and urgencies for which the system is designed to accommodate. The MPS receives fast shutdown (FSD) signals generated by the beam loss system and inhibits the beam or reduces the beam intensity within a macropulse when the beam losses at several places along the accelerator beam line are higher than acceptable values. TTL or relay contact signals from the vacuum system, toroids, magnet systems etc., are chosen with polarities that ensure safe operation of the accelerator from unintended events such as cable disconnection in the harsh industrial environment of the experimental hall. A RS422 serial communication scheme is used to interface the operation permit generator module and a large number of movable devices each reporting multi-bit status. The system also supports operations at user defined lower beam levels for system conunissioning. The machine protection system is implemented with two commercially available off-the-shelf VMEbus based modules with on board FPGA devices. The system is monitored and controlled via the VMEbus by a single board CPU

  12. Diffuser/ejector system for a very high vacuum environment

    NASA Technical Reports Server (NTRS)

    Riggs, K. E.; Wojciechowski, C. J. (Inventor)

    1984-01-01

    Turbo jet engines are used to furnish the necessary high temperature, high volume, medium pressure gas to provide a high vacuum test environment at comparatively low cost for space engines at sea level. Moreover, the invention provides a unique way by use of the variable area ratio ejectors with a pair of meshing cones are used. The outer cone is arranged to translate fore and aft, and the inner cone is interchangeable with other cones having varying angles of taper.

  13. RHIC 28 MHZ ACCELERATING CAVITY SYSTEM.

    SciTech Connect

    ROSE,J.; BRENNAN,J.M.; CAMPBELL,A.; KWIATKOWSKI,S.; RATTI,A.; PIRKL,W.

    2001-06-18

    The 28 MHz accelerating system consists of a quarter wave cavity driven by an inductively coupled 100kW tetrode amplifer and 1kW solid state driver amplifer. 40dB of rf feedback closed around the cavity and amplifers reduces small perturbations within the loop by a factor of 100, and reduces the time required to shift the phase at transition by a factor of 10, limited by the saturation of the drive chain. The cavity is tuned over a 200kHz range by a mechanical tuner which varies the gap capacitance. Broadband HOM damping is provided by two orthogonal loop coupled high pass filters. Design parameters and commissioning results are presented.

  14. Systems and methods for the magnetic insulation of accelerator electrodes in electrostatic accelerators

    DOEpatents

    Grisham, Larry R

    2013-12-17

    The present invention provides systems and methods for the magnetic insulation of accelerator electrodes in electrostatic accelerators. Advantageously, the systems and methods of the present invention improve the practically obtainable performance of these electrostatic accelerators by addressing, among other things, voltage holding problems and conditioning issues. The problems and issues are addressed by flowing electric currents along these accelerator electrodes to produce magnetic fields that envelope the accelerator electrodes and their support structures, so as to prevent very low energy electrons from leaving the surfaces of the accelerator electrodes and subsequently picking up energy from the surrounding electric field. In various applications, this magnetic insulation must only produce modest gains in voltage holding capability to represent a significant achievement.

  15. BIOCONAID System (Bionic Control of Acceleration Induced Dimming). Final Report.

    ERIC Educational Resources Information Center

    Rogers, Dana B.; And Others

    The system described represents a new technique for enhancing the fidelity of flight simulators during high acceleration maneuvers. This technique forces the simulator pilot into active participation and energy expenditure similar to the aircraft pilot undergoing actual accelerations. The Bionic Control of Acceleration Induced Dimming (BIOCONAID)…

  16. REQUIREMENTS AND GUIDELINES FOR NSLS EXPERIMENTAL BEAM LINE VACUUM SYSTEMS-REVISION B.

    SciTech Connect

    FOERSTER,C.

    1999-05-01

    Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas after a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic photons of the x-ray ring, beryllium windows are used at various beam line locations so that the monochromator, mirror box or sample chamber may be used in a helium atmosphere or rough vacuum. The window separates ring vacuum from the environment of the downstream beam line components. The stored beam lifetime in the storage rings and the maintenance of desirable reflection properties of optical surfaces depend upon hydrocarbon-free, ultra-high vacuum systems. Storage ring vacuum systems will operate at pressures of {approximately} 1 x 10{sup {minus}10} Torr without beam and {approximately} 1 x 10{sup {minus}9} Torr with beam. Systems are free of hydrocarbons in the sense that no pumps, valves, etc. containing organics are used. Components are all-metal, chemically cleaned and bakeable. To the extent that beam lines share a common vacuum with the storage ring, the same criteria will hold for beam line components. The design philosophy for NSLS beam lines is to use all-metal, hydrocarbon-free front end components and recommend that experimenters use this approach for common vacuum hardware downstream of front

  17. Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata.

    PubMed

    Roy, Anindya; Bhole, R B; Nandy, Partha P; Yadav, R C; Pal, Sarbajit; Roy, Amitava

    2015-03-01

    The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system. PMID:25832222

  18. Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata

    NASA Astrophysics Data System (ADS)

    Roy, Anindya; Bhole, R. B.; Nandy, Partha P.; Yadav, R. C.; Pal, Sarbajit; Roy, Amitava

    2015-03-01

    The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system.

  19. Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata

    SciTech Connect

    Roy, Anindya Bhole, R. B.; Nandy, Partha P.; Yadav, R. C.; Pal, Sarbajit; Roy, Amitava

    2015-03-15

    The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system.

  20. Electrical Strength of Multilayer Vacuum Insulators

    SciTech Connect

    Harris, J R; Kendig, M; Poole, B; Sanders, D M; Caporaso, G J

    2008-07-01

    The electrical strength of vacuum insulators is a key constraint in the design of particle accelerators and pulsed power systems. Vacuum insulating structures assembled from alternating layers of metal and dielectric can result in improved performance compared to conventional insulators, but previous attempts to optimize their design have yielded seemingly inconsistent results. Here, we present two models for the electrical strength of these structures, one assuming failure by vacuum arcing between adjacent metal layers and the other assuming failure by vacuum surface flashover. These models predict scaling laws which are in agreement with the experimental data currently available.

  1. Radio frequency systems for present and future accelerators

    SciTech Connect

    Raka, E.C.

    1987-01-01

    Rf systems are described for the FNAL Main Ring and Tevatron Ring, CERN SPS and LEP, and HERA proton acceleration system, CERN PS e/sup +/e/sup minus/ acceleration system, and CERN EPA monochromatic cavity. Low impedance rf systems in CERN ISR, the Brookhaven CBA, and SSC are also discussed.

  2. Vacuum Technology

    SciTech Connect

    Biltoft, P J

    2004-10-15

    The environmental condition called vacuum is created any time the pressure of a gas is reduced compared to atmospheric pressure. On earth we typically create a vacuum by connecting a pump capable of moving gas to a relatively leak free vessel. Through operation of the gas pump the number of gas molecules per unit volume is decreased within the vessel. As soon as one creates a vacuum natural forces (in this case entropy) work to restore equilibrium pressure; the practical effect of this is that gas molecules attempt to enter the evacuated space by any means possible. It is useful to think of vacuum in terms of a gas at a pressure below atmospheric pressure. In even the best vacuum vessels ever created there are approximately 3,500,000 molecules of gas per cubic meter of volume remaining inside the vessel. The lowest pressure environment known is in interstellar space where there are approximately four molecules of gas per cubic meter. Researchers are currently developing vacuum technology components (pumps, gauges, valves, etc.) using micro electro mechanical systems (MEMS) technology. Miniature vacuum components and systems will open the possibility for significant savings in energy cost and will open the doors to advances in electronics, manufacturing and semiconductor fabrication. In conclusion, an understanding of the basic principles of vacuum technology as presented in this summary is essential for the successful execution of all projects that involve vacuum technology. Using the principles described above, a practitioner of vacuum technology can design a vacuum system that will achieve the project requirements.

  3. The Classical Vacuum.

    ERIC Educational Resources Information Center

    Boyer, Timothy H.

    1985-01-01

    The classical vacuum of physics is not empty, but contains a distinctive pattern of electromagnetic fields. Discovery of the vacuum, thermal spectrum, classical electron theory, zero-point spectrum, and effects of acceleration are discussed. Connection between thermal radiation and the classical vacuum reveals unexpected unity in the laws of…

  4. Vacuum control subsystem for the Fermilab Tevatron

    SciTech Connect

    Zagel, J.R.; Chapman, L.J.

    1981-06-01

    The CAMAC 170 module and CIA crate provide a convenient, cost effective method of interfacing any system requiring a large number of simple devices to be multiplexed into the Accelerator Control System. The system is ideal for relatively slowly changing systems where ten bit analog to digital conversions are sufficiently accurate. Together with vacuum interface CIA cards and prom-based software resident in the 170, this system is used to provide intelligent local monitoring and control for the Tevatron vacuum subsystems. Although not implemented in the vacuum interface, digital to analog converters could be included on the plug in modules as well, providing a total digital and analog multiplexing scheme. 2 refs.

  5. Systems and Methods for Fabricating Carbon Nanotube-Based Vacuum Electronic Devices

    NASA Technical Reports Server (NTRS)

    Manohara, Harish (Inventor); Toda, Risaku (Inventor); Del Castillo, Linda Y. (Inventor); Murthy, Rakesh (Inventor)

    2015-01-01

    Systems and methods in accordance with embodiments of the invention proficiently produce carbon nanotube-based vacuum electronic devices. In one embodiment a method of fabricating a carbon nanotube-based vacuum electronic device includes: growing carbon nanotubes onto a substrate to form a cathode; assembling a stack that includes the cathode, an anode, and a first layer that includes an alignment slot; disposing a microsphere partially into the alignment slot during the assembling of the stack such that the microsphere protrudes from the alignment slot and can thereby separate the first layer from an adjacent layer; and encasing the stack in a vacuum sealed container.

  6. Thermal Stabilization in a High Vacuum Cryogenic Optical System

    NASA Astrophysics Data System (ADS)

    Wallace, Rosa; Cripe, Jonathan; Corbitt, Thomas

    2016-03-01

    The existing technology for gravitational wave detection is limited in part by quantum noise. In our tabletop experiments, we are attempting to lower the noise floor to the quantum limit through the use of a seismically isolated cryogenic high vacuum environment, with the intention of exploring different methods to reduce quantum noise. In the development phase of this environment, we have implemented a customized strategy of ultraviolet irradiation combined with cryogenically cooled radiation shielding to reduce the impact of water vapor and blackbody radiation on the thermal stability of the cryogenic micro-components. Supported by National Science Foundation REU Site #1262890 and CAREER Award #1150531.

  7. DC photogun vacuum characterization through photocathode lifetime studies

    SciTech Connect

    Marcy Stutzman; Joseph Grames; Matt Poelker; Kenneth Surles-Law; Philip Adderley

    2007-07-02

    Excellent vacuum is essential for long photocathode lifetimes in DC high voltage photoelectron guns. Vacuum Research at Thomas Jefferson National Accelerator Facility has focused on characterizing the existing vacuum systems at the CEBAF polarized photoinjector and on quantifying improvements for new systems. Vacuum chamber preprocessing, full activation of NEG pumps and NEG coating the chamber walls should improve the vacuum within the electron gun, however, pressure measurement is difficult at pressures approaching the extreme-high-vacuum (XHV) region and extractor gauge readings are not significantly different between the improved and original systems. The ultimate test of vacuum in a DC high voltage photogun is the photocathode lifetime, which is limited by the ionization and back-bombardment of residual gasses. Discussion will include our new load-locked gun design as well as lifetime measurements in both our operational and new photo-guns, and the correlations between measured vacuum and lifetimes will be investigated.

  8. Survey of Electronic Safety Systems in Accelerator Applications

    NASA Astrophysics Data System (ADS)

    Mahoney, K.

    1997-05-01

    This paper presents the preliminary results and analysis of a comprehensive survey of the implementation of accelerator safety interlock systems at over 20 international labs. At the present time there is not a self consistent means to evaluate both the experience and level of protection provided by electronic safety interlock systems. This research is intended to analyze the strengths and weaknesses of several different types of interlock system implementation methodologies. Research, medical, and industrial accelerators are compared. The CEBAF accelerator at Thomas Jefferson National Accelerator Facility (Jefferson Lab) was one of the first large particle accelerators to implement a safety interlock system using programmable logic controllers. Since that time all of the major new U.S. accelerator construction projects plan to use some form of programmable electronics as part of a safety interlock system in some capacity. To the author's knowledge such a compilation has not been presented before.

  9. Comparison of occlusion break responses and vacuum rise times of phacoemulsification systems

    PubMed Central

    2014-01-01

    Background Occlusion break surge during phacoemulsification cataract surgery can lead to potential surgical complications. The purpose of this study was to quantify occlusion break surge and vacuum rise time of current phacoemulsification systems used in cataract surgery. Methods Occlusion break surge at vacuum pressures between 200 and 600 mmHg was assessed with the Infiniti® Vision System, the WhiteStar Signature® Phacoemulsification System, and the Centurion® Vision System using gravity-fed fluidics. Centurion Active FluidicsTM were also tested at multiple intraoperative pressure target settings. Vacuum rise time was evaluated for Infiniti, WhiteStar Signature, Centurion, and Stellaris® Vision Enhancement systems. Rise time to vacuum limits of 400 and 600 mmHg was assessed at flow rates of 30 and 60 cc/minute. Occlusion break surge was analyzed by 2-way analysis of variance. Results The Centurion system exhibited substantially less occlusion break surge than the other systems tested. Surge area with Centurion Active Fluidics was similar to gravity fluidics at an equivalent bottle height. At all Centurion Active Fluidics intraoperative pressure target settings tested, surge was smaller than with Infiniti and WhiteStar Signature. Infiniti had the fastest vacuum rise time and Stellaris had the slowest. No system tested reached the 600-mmHg vacuum limit. Conclusions In this laboratory study, Centurion had the least occlusion break surge and similar vacuum rise times compared with the other systems tested. Reducing occlusion break surge may increase safety of phacoemulsification cataract surgery. PMID:25074069

  10. Thermal mechanical analyses of large diameter ion accelerator systems

    SciTech Connect

    Brophy, J.R.; Aston, G.

    1989-01-01

    Thermal mechanical analyses of large diameter ion accelerator systems are performed using commercially available finite element software executed on a desktop computer. Finite element models of a 30-cm-diameter accelerator system formulated using plate/shell elements give calculated results which agree well with similar published obtained on a mainframe computer. Analyses of a 50-cm-diameter, three-grid accelerator system using measured grid temperatures (corresponding to discharge powers of 653 and 886 watts) indicate that thermally induced grid movements need not be the performance limiting phenomena for accelerator systems of this size. 8 refs.

  11. Thermal mechanical analyses of large diameter ion accelerator systems

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Aston, Graeme

    1989-01-01

    Thermal mechanical analyses of large diameter ion accelerator systems are performed using commercially available finite element software executed on a desktop computer. Finite element models of a 30-cm-diameter accelerator system formulated using plate/shell elements give calculated results which agree well with similar published obtained on a mainframe computer. Analyses of a 50-cm-diameter, three-grid accelerator system using measured grid temperatures (corresponding to discharge powers of 653 and 886 watts) indicate that thermally induced grid movements need not be the performance limiting phenomena for accelerator systems of this size.

  12. Tripartite entanglement of fermionic system in accelerated frames

    SciTech Connect

    Khan, Salman

    2014-09-15

    The dynamics of tripartite entanglement of fermionic system in noninertial frames through linear contraction criterion when one or two observers are accelerated is investigated. In one observer accelerated case the entanglement measurement is not invariant with respect to the partial realignment of different subsystems and for two observers accelerated case it is invariant. It is shown that the acceleration of the frame does not generate entanglement in any bipartite subsystems. Unlike the bipartite states, the genuine tripartite entanglement does not completely vanish in both one observer accelerated and two observers accelerated cases even in the limit of infinite acceleration. The degradation of tripartite entanglement is fast when two observers are accelerated than when one observer is accelerated. It is shown that tripartite entanglement is a better resource for quantum information processing than the bipartite entanglement in noninertial frames. - Highlights: • Tripartite entanglement of fermionic system in noninertial frames is studied. • Linear contraction criterion for quantifying tripartite entanglement is used. • Acceleration does not produce any bipartite entanglement. • The invariance of entanglement quantifier depends on accelerated observers. • The tripartite entanglement degrades against the acceleration, it never vanishes.

  13. OPERATION OF FUSION REACTORS IN ONE ATMOSPHERE OF AIR INSTEAD OF VACUUM SYSTEMS

    SciTech Connect

    Roth, J. Reece

    2009-07-26

    Engineering design studies of both magnetic and inertial fusion power plants have assumed that the plasma will undergo fusion reactions in a vacuum environment. Operation under vacuum requires an expensive additional major system for the reactor-a vacuum vessel with vacuum pumping, and raises the possibility of sudden unplanned outages if the vacuum containment is breached. It would be desirable in many respects if fusion reactors could be made to operate at one atmosphere with air surrounding the plasma, thus eliminating the requirement of a pressure vessel and vacuum pumping. This would have obvious economic, reliability, and engineering advantages for currently envisaged power plant reactors; it would make possible forms of reactor control not possible under vacuum conditions (i.e. adiabatic compression of the fusion plasma by increasing the pressure of surrounding gas); it would allow reactors used as aircraft engines to operate as turbojets or ramjets in the atmosphere, and it would allow reactors used as fusion rockets to take off from the surface of the earth instead of low earth orbit.

  14. Vacuum system for the Synchrotron X-ray Source at Argonne

    SciTech Connect

    Wehrle, R.; Moenich, J.; Kim, S.; Nielsen, R.

    1987-01-01

    The vacuum system of the APS storage ring is designed to maintain a beam-on operating pressure of 1 nTorr or less in order to achieve a positron beam lifetime of approximately 20 hours. The vacuum chamber is an aluminum extrusion containing a beam chamber and antechamber. The primary source of the pumping is with NeG strips. The design and location of the crotches and strip absorbers are based on the distribution of the bending magnet synchrotron radiations.

  15. Cold Vacuum Drying facility potable water system design description (SYS 26)

    SciTech Connect

    PITKOFF, C.C.

    1999-07-02

    This document describes the Cold Vacuum Drying Facility (CVDF) potable water (PW) system. The PW system provides potable water to the CVDF for supply to sinks, water closets, urinals, showers, custodial service sinks, drinking fountains, the decontamination shower, supply water to the non-PW systems, and makeup water for the de-ionized water system.

  16. Phase velocity of the TEM (1,0)+TEM (0,1) mode laser and electron accelerations in vacuum

    SciTech Connect

    Wu, L.; Kong, Q.; Ho, Y. K.; Wang, P. X.; Xu, J. J.; Lin, D.; Kawata, S.

    2007-04-01

    Unlike at any single TEM (n, m) mode laser, there is a subluminous phase velocity region located along the central region of a TEM (1,0)+TEM (0,1) mode laser. In conjunction with the high longitudinal electric field in this region, it forms another acceleration channel, which also locates inside the transverse ponderomotive potential trap. Through simulation, it is found that relativistic electrons injected into this acceleration channel can stand at the acceleration phase for a long time and be synchronously accelerated to high energies. Also, the accelerated electrons can be well confined inside the trap avoiding the transverse scattering problem.

  17. Advanced Microgravity Acceleration Measurement Systems (AMAMS) Being Developed

    NASA Technical Reports Server (NTRS)

    Sicker, Ronald J.; Kacpura, Thomas J.

    2003-01-01

    The Advanced Microgravity Acceleration Measurement Systems (AMAMS) project is part of NASA s Instrument Technology Development program to develop advanced sensor systems. The primary focus of the AMAMS project is to develop microelectromechanical systems (MEMS) for acceleration sensor systems to replace existing electromechanical sensor systems presently used to assess relative gravity levels aboard spacecraft. These systems are used to characterize both vehicle and payload responses to low-gravity vibroacoustic environments. The collection of microgravity acceleration data is useful to the microgravity life sciences, microgravity physical sciences, and structural dynamics communities. The inherent advantages of semiconductor-based systems are reduced size, mass, and power consumption, with enhanced long-term calibration stability.

  18. Cold Vacuum Drying facility HVAC system design description (SYS 30-1 THRU 30-5)

    SciTech Connect

    PITKOFF, C.C.

    1999-07-02

    This document describes the Cold Vacuum Drying Facility (CVDF) heating, ventilation, and air conditioning system (HVAC). The CVDF HVAC system consists of the Administrative building HVAC system, the process bay recirculation HVAC system, the process bay local HVAC and process vent system, the process general supply/exhaust HVAC system, and the Reference air system. These HVAC sub-systems support the CVDF process and provide secondary confinement of contamination and the required filtration of exhaust.

  19. Modeling of RHIC insulating vacuum for system pumpdown characteristics

    SciTech Connect

    Todd, R.J.; Pate, D.J.; Welch, K.M.

    1993-06-01

    This paper presents a model for predicting the pumpdown characteristics of a 480 m RHIC (Relativistic Heavy Ion Collider) vacuum cryostat. The longitudinal and transverse conductances of a typical cryostat were calculated. A voltage analogue of these conductances was constructed for room temperature conditions. The total longitudinal conductance of a room temperature cryostat was thereby achieved. This conductance was then used to calculate the diameter of an equivalent long outgassing tube, having more convenient analytical expressions for pressure profiles when pumped. The equivalent of a unit outgassing rate for this tube was obtained using previously published MLI (multi-layer insulation) outgassing data. With this model one is then able to predict a cryostat pumpdown rate as a function of the location and size of roughing pumps.

  20. Methods for identification and verification using vacuum XRF system

    NASA Technical Reports Server (NTRS)

    Schramm, Fred (Inventor); Kaiser, Bruce (Inventor)

    2005-01-01

    Apparatus and methods in which one or more elemental taggants that are intrinsically located in an object are detected by x-ray fluorescence analysis under vacuum conditions to identify or verify the object's elemental content for elements with lower atomic numbers. By using x-ray fluorescence analysis, the apparatus and methods of the invention are simple and easy to use, as well as provide detection by a non line-of-sight method to establish the origin of objects, as well as their point of manufacture, authenticity, verification, security, and the presence of impurities. The invention is extremely advantageous because it provides the capability to measure lower atomic number elements in the field with a portable instrument.

  1. UPGRADE OF RHIC VACUUM SYSTEMS FOR HIGH LUMINOSITY OPERATION.

    SciTech Connect

    HSEUH, H.C.; MAPES, M.; SMART, L.A.; TODD, R.; WEISS, D.

    2005-05-16

    With increasing ion beam intensity during recent RHIC operations, rapid pressure rises of several decades were observed at most warm sections and at a few cold sections. The pressure rises are associated with electron multi-pacting, electron stimulated desorption and beam ion induced desorption and have been one of the major intensity and luminosity limiting factors for RHIC. Improvement of the warm sections has been carried out in the last few years. Extensive in-situ bakes, additional UHV pumping and anti-grazing ridges have been implemented. Several hundred meters of NEG coated beam pipes have been installed and activated. Vacuum monitoring and logging were enhanced. Preventive measures, such as pumping before cool down to reduce monolayer condensates, were also taken to suppress the pressure rises in the cold sections. The effectiveness of these measures in reducing the pressure rises during machine studies and during physics runs are discussed and summarized.

  2. Engineering Specification Document (ESD) of X-ray Vacuum Transport System (XVTS) for LCLS XTOD

    SciTech Connect

    Shen, S

    2006-01-25

    The vacuum system of the X-Ray Vacuum Transport System (XVTS) for the Linac Coherent Light Source (LCLS) X-ray Transport, Optics and Diagnostics (XTOD) system has been analyzed and configured by the Lawrence Livermore National Laboratory's New Technologies Engineering Division (NTED) as requested by the SLAC/LCLS program. The preliminary system layout, detailed analyses and suggested selection of the vacuum components for the XTOD tunnel section are presented in the preliminary design report [1]. This document briefly reviews the preliminary design and provides engineering specifications for the system, which can be used as 'design to' specifications for the final design. Also included are the requirements of plans for procurement, mechanical integration, schedule and the cost estimates.

  3. Presentation on a Space Acceleration Measurement System (SAMS)

    NASA Technical Reports Server (NTRS)

    Chase, Theodore L.

    1990-01-01

    The primary objective of the Space Acceleration Measurement Systems (SAMS) project is to provide an acceleration measurement system capable of serving a wide variety of space experiments. The design of the system being developed under this project takes into consideration requirements for experiments located in the middeck, in the orbiter bay, and in Spacelab. In addition to measuring, conditioning, and recording accelerations, the system will be capable of performing complex calculations and interactive control. The main components consist of a remote triaxial optical storage device. In operation, the triaxial sensor head produces output signals in response to acceleration inputs. These signals are preamplified, filtered and converted into digital data which is then transferred to optical memory. The system design is modular, facilitating both software and hardware upgrading as technology advances. Two complete acceleration measurement flight systems will be build and tested under this project.

  4. Cold Vacuum Drying facility effluent drains system design description (SYS 18)

    SciTech Connect

    TRAN, Y.S.

    2000-05-11

    The Cold Vacuum Drying (CVD) Facility provides required process systems, supporting equipment, and facilities needed for the Spent Nuclear Fuel (SNF) mission. This system design description (SDD) addresses the effluent drain system (EFS), which supports removal of water from the process bay floors. The discussion that follows is limited to piping, valves, components, and the process bay floor drain retention basin.

  5. Architecture and operation of the Z Pulsed Power Facility vacuum system.

    SciTech Connect

    Riddle, Allen Chauncey; Petmecky, Don; Weed, John Woodruff

    2010-11-01

    The Z Pulsed Power Facility at Sandia National Laboratories in Albuquerque, New Mexico, USA is one of the world's premier high energy density physics facilities. The Z Facility derives its name from the z-pinch phenomena which is a type of plasma confinement system that uses the electrical current in the plasma to generate a magnetic field that compresses it. Z refers to the direction of current flow, the z axis in a three dimensional Cartesian coordinate system. The multiterawatt, multimegajoule electrical pulse the Facility produces is 100-400 nanoseconds in time. Research and development programs currently being conducted on the Z Facility include inertial confinement fusion, dynamic material properties, laboratory astrophysics and radiation effects. The Z Facility vacuum system consists of two subsystems, center section and load diagnostics. Dry roughing pumps and cryogenic high vacuum pumps are used to evacuate the 40,000 liter, 200 square meter center section of the facility where the experimental load is located. Pumping times on the order of two hours are required to reduce the pressure from atmospheric to 10{sup -5} Torr. The center section is cycled from atmosphere to high vacuum for each experiment. The facility is capable of conducting one to two experiments per day. Numerous smaller vacuum pumping systems are used to evacuate load diagnostics. The megajoules of energy released during an experiment causes damage to the Facility that presents numerous challenges for reliable operation of the vacuum system.

  6. Summary of ACSL Simulations of the MSRE Auxiliary Charcoal Bed Vacuum System

    SciTech Connect

    Damiano, B

    2000-10-26

    The simulation of the Auxiliary Charcoal Bed (ACB) Vacuum System was performed to evaluate the original vacuum system design, detect and identify design deficiencies, investigate the effects of proposed corrections on system performance, and generally aid in refining the system design before construction and mockup testing. The simulation was performed by using the Advanced Continuous Simulation Language (ACSL). The vacuum system design goals are to provide approximately 20 SCFM of both booster gas and purge gas through the system and maintain a flow of approximately 40 SCFM with a velocity of 50 to 75 f/sec at the entrance to the cyclone separator. The model results showed that the original system design was incapable of meeting the system performance goals. Further simulations showed that the following modifications to the original vacuum system design were required to make the system performance acceptable; (1) Remove valve PCV4. (2) Modify the flow controllers FTC3 and FTC4 from the original flow range of 0-17.6 SCFM (0-500 SLM) to 0-35.3 SCFM (0-1000 SLM). (3) Replace the bellows sealed valves SV-1, SV-3A, SV-3B, SV-4A, and SV-4B with less restrictive ball valves. The simulation results saved considerable time and effort by identifying flaws in the original system design. Early identification of these flaws and the use of the simulation model to investigate possible solutions allowed corrective modifications to be made before construction of the mock up test facility.

  7. Cryogenic Viscous Compressor Development and Modeling for the ITER Vacuum System

    SciTech Connect

    Baylor, Larry R; Meitner, Steven J; Barbier, Charlotte N; Combs, Stephen Kirk; Duckworth, Robert C; Edgemon, Timothy D; Rasmussen, David A; Hechler, Michael P; Kersevan, R.; Dremel, M.; Pearce, R.J.H.; Boissin, Jean Claude

    2011-01-01

    The ITER vacuum system requires a roughing pump system that can pump the exhaust gas from the torus cryopumps to the tritium exhaust processing plant. The gas will have a high tritium content and therefore conventional vacuum pumps are not suitable. A pump called a cryogenic viscous compressor (CVC) is being designed for the roughing system to pump from ~500 Pa to 10 Pa at flow rates of 200 Pa-m3/ s. A unique feature of this pump is that is allows any helium in the gas to flow through the pump where it is sent to the detritiation system before exhausting to atmosphere. A small scale prototype of the CVC is being tested for heat transfer characteristics and compared to modeling results to ensure reliable operation of the full scale CVC. Keywords- ITER; vacuum; fuel cycle

  8. Spent nuclear fuel project cold vacuum drying facility process water conditioning system design description

    SciTech Connect

    IRWIN, J.J.

    1998-11-30

    This document provides the System Design Description (SDD) for the Cold Vacuum Drying Facility (CVDF) Process Water Conditioning (PWC) System. The SDD was developed in conjunction with HNF-SD-SNF-SAR-002, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of Processing Systems (Garvin 1998), the HNF-SD-SNF-DRD-O02, 1998, Cold Vacuum Drying Facility Design Requirements, and the CVDF Design Summary Report. The SDD contains general descriptions of the PWC equipment, the system functions, requirements and interfaces. The SDD provides references for design and fabrication details, operation sequences and maintenance. This SDD has been developed for the SNFP Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved.

  9. The LLNL Accelerator Mass Spectrometry System for Biochemical 14C-Measurements

    SciTech Connect

    Ognibene, T J; Bench, G; Brown, T A; Vogel, J S

    2002-10-31

    We report on recent improvements made to our 1 MV accelerator mass spectrometry system that is dedicated to {sup 14}C quantification of biochemical samples. Increased vacuum pumping capacity near the high voltage terminal has resulted in a 2-fold reduction of system backgrounds to 0.04 amol {sup 14}C/mg carbon. Carbon ion transmission through the accelerator has also improved a few percent. We have also developed tritium measurement capability on this spectrometer. The {sup 3}H/{sup 1}H isotopic ratio of a milligram-sized processed tap water sample has been measured at 4 {+-} 1 x 10{sup -16} (430 {+-} 110 {micro}Bq/mg H). Measurement throughput for a typical biochemical {sup 3}H sample is estimated to be {approx}10 minutes/sample.

  10. 2-kW Solar Dynamic Space Power System Tested in Lewis' Thermal Vacuum Facility

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Working together, a NASA/industry team successfully operated and tested a complete solar dynamic space power system in a large thermal vacuum facility with a simulated sun. This NASA Lewis Research Center facility, known as Tank 6 in building 301, accurately simulates the temperatures, high vacuum, and solar flux encountered in low-Earth orbit. The solar dynamic space power system shown in the photo in the Lewis facility, includes the solar concentrator and the solar receiver with thermal energy storage integrated with the power conversion unit. Initial testing in December 1994 resulted in the world's first operation of an integrated solar dynamic system in a relevant environment.

  11. Cold Vacuum Drying (CVD) Facility General Service Helium System Design Description

    SciTech Connect

    FARWICK, C.C.

    1999-07-06

    This document describes the Cold Vacuum Drying Facility general service helium system (GSHe). The GSHe is a general service facility process support system, but does include safety-class systems, structures and components providing protection to the offsite public. The GSHe also performs safety-significant functions that provide protection to onsite workers. The GSHe essential function is to provide helium to support process functions during all phases of facility operations. GSHe helium is used to purge the cask and the MCO in order to maintain their internal atmospheres below hydrogen flammability concentrations. The GSHe also supplies helium to purge the PWC lines and components and the VPS vacuum pump.

  12. Characterization of the CEBAF 100 kV DC GaAs Photoelectron Gun Vacuum System

    SciTech Connect

    Stutzman, M L; Adderley, P; Brittian, J; Clark, J; Grames, J; Hansknecht, J; Myneni, G R; Poelker, M

    2007-05-01

    A vacuum system with pressure in the low ultra-high vacuum (UHV) range is essential for long photocathode lifetimes in DC high voltage GaAs photoguns. A discrepancy between predicted and measured base pressure in the CEBAF photoguns motivated this study of outgassing rates of three 304 stainless steel chambers with different pretreatments and pump speed measurements of non-evaporable getter (NEG) pumps. Outgassing rates were measured using two independent techniques. Lower outgassing rates were achieved by electropolishing and vacuum firing the chamber. The second part of the paper describes NEG pump speed measurements as a function of pressure through the lower part of the UHV range. Measured NEG pump speed is high at pressures above 5×10-11 Torr, but may decrease at lower pressures depending on the interpretation of the data. The final section investigates the pump speed of a locally produced NEG coating applied to the vacuum chamber walls. These studies represent the first detailed vacuum measurements of CEBAF photogun vacuum chambers.

  13. Characterization of the CEBAF 100 kV DC GaAs photoelectron gun vacuum system

    NASA Astrophysics Data System (ADS)

    Stutzman, M. L.; Adderley, P.; Brittian, J.; Clark, J.; Grames, J.; Hansknecht, J.; Myneni, G. R.; Poelker, M.

    2007-05-01

    A vacuum system with pressure in the low ultra-high vacuum (UHV) range is essential for long photocathode lifetimes in DC high voltage GaAs photoguns. A discrepancy between predicted and measured base pressure in the CEBAF photoguns motivated this study of outgassing rates of three 304 stainless steel chambers with different pretreatments and pump speed measurements of non-evaporable getter (NEG) pumps. Outgassing rates were measured using two independent techniques. Lower outgassing rates were achieved by electropolishing and vacuum firing the chamber. The second part of the paper describes NEG pump speed measurements as a function of pressure through the lower part of the UHV range. Measured NEG pump speed is high at pressures above 5×10 -11 Torr, but may decrease at lower pressures depending on the interpretation of the data. The final section investigates the pump speed of a locally produced NEG coating applied to the vacuum chamber walls. These studies represent the first detailed vacuum measurements of CEBAF photogun vacuum chambers.

  14. Setting up of in-vacuum PIXE system for direct elemental analysis of thick solid environmental samples.

    PubMed

    Rihawy, M S; Ismail, I M; Halloum, D

    2016-04-01

    Experimental set-up, development, characterization, and calibration of an in-vacuum PIXE system at the tandem accelerator facility of the Atomic Energy Commission of Syria (AECS) is described. The PIXE system calibration involved experimental characterization of the X-ray detector parameters and careful determination of the H-values that control dependence of the detector solid angle with the X-ray energies and correct imperfect values of the detector efficiency. Setting up of an electron flood gun to compensate charge built up and utilization of a beam profile monitor to perform indirect measurement of the beam charge, provide a direct PIXE measurement of thick insulating samples in-vacuum. The PIXE system has been subsequently examined to verify its ability to perform direct PIXE measurements on geological materials. A combination of minimum sample preparation procedures and specific experimental conditions applied enables simple and accurate elemental analysis. Elemental concentrations of several elements heavier than sodium in different reference geological samples, at about 5-10% absolute accuracy for most elements, have been determined. Comprehensive discussion of the obtained elemental concentration values, for most elements of visible X-ray peaks in the PIXE spectra, has been considered. PMID:26803668

  15. Vacuum system problems of EBT: a steady-state fusion experiment

    SciTech Connect

    Livesey, R.L.

    1981-01-01

    Many of the vacuum problems faced by EBT will soon be shared by other plasma devices as high-power microwave systems and long pulse lengths become more common. The solutions used on EBT (such as the raised lip with elastomer seal) are not unique; however, experience has shown that microwave-compatible designs must be carefully thought out. All details of the vacuum must be carefully thought out. All details of the vacuum must be carefully screened in advance to insure that microwaves do not leak into pumps or diagnostics where they can cause major damage. Sputter coating, which even now is noticeably present in most pulsed plasma systems, becomes much worse as systems approach steady state. And finally, radiation degradation of components which is presently a minor problem will become significant on high-power microwave-fed devices, such as EBT-P.

  16. Development of a local vacuum system for focused ion beam machining

    NASA Astrophysics Data System (ADS)

    Masuzawa, Tsuneaki; Yoshida, Yoshikazu; Ikeda, Hiromichi; Oguchi, Keigo; Yamagishi, Hikaru; Wakabayashi, Yuji

    2009-07-01

    A local vacuum system for focused ion beam (FIB) processing, with a workpiece set in the air, has been developed. The local vacuum apparatus had a double-wall cylinder structure, used a differential exhaust, and each cylinder was connected to a vacuum exhaust pump. When the gap between the workpiece and the apparatus was 10 μm, the pressure of beam line in the machining head achieved 2.1×10-3 Pa. In addition, a visualization system was developed by visualizing the current flow out from a sample by FIB irradiation. With this system, it is possible to conduct focus adjustments of the FIB and shape recognition on a workpiece in the order of microns.

  17. Design of MEMS accelerometer based acceleration measurement system for automobiles

    NASA Astrophysics Data System (ADS)

    Venkatesh, K. Arun; Mathivanan, N.

    2012-10-01

    Design of an acceleration measurement system using a MEMS accelerometer to measure acceleration of automobiles in all the three axes is presented. Electronic stability control and anti-lock breaking systems in automobiles use the acceleration measurements to offer safety in driving. The system uses an ARM microcontroller to quantize the outputs of accelerometer and save the measurement data on a microSD card. A LabVIEW program has been developed to analyze the longitudinal acceleration measurement data and test the measurement system. Random noises generated and added with measurement data during measurement are filtered by a Kalman filter implemented in LabVIEW. Longitudinal velocity of the vehicle is computed from the measurement data and displayed on a graphical chart. Typical measurement of velocity of a vehicle at different accelerations and decelerations is presented.

  18. Development of a high vacuum sample preparation system for helium mass spectrometer

    NASA Astrophysics Data System (ADS)

    Kumar, P.; Das, N. K.; Mallik, C.; Bhandari, R. K.

    2012-11-01

    A high vacuum sample preparation system for the 3He/4He ratio mass spectrometer (Helix SFT) has been developed to remove all the gaseous constituents excluding helium from the field gases. The sample preparation system comprises of turbo molecular pump, ion pump, zirconium getter, pipettes and vacuum gauges with controller. All these are fitted with cylindrical SS chamber using all metal valves. The field samples are initially treated with activated charcoal trap immersed in liquid nitrogen to cutoff major impurities and moisture present in the sample gas. A sample of 5 ml is collected out of this stage at a pressure of 10-2 mbar. This sample is subsequently purified at a reduced pressure of 10-7 mbar before it is injected into the ion source of the mass spectrometer. The sample pressure was maintained below 10-7 mbar with turbo molecular vacuum pumps and ion pumps. The sample gas passes through several getter elements and a cold finger with the help of manual high vacuum valves before it is fed to the mass spectrometer. Thus the high vacuum sample preparation system introduces completely clean, dry and refined helium sample to the mass spectrometer for best possible analysis of isotopic ratio of helium.

  19. Summary Report for the Investigation and Performance of the IAAC Bell Jar Vacuum System

    SciTech Connect

    Bohne, William A.; Kramer, Donald C.

    1996-02-26

    Operations associated with the vacuum processing of the F-2 converter during the RTG assembly operation were initiated on February 16 and continued through February 18, 1996. During vacuum processing on February 17, pressures less than 1x10 sub -5 torr could not be attained as required by the procedure. Although pressure readings in the 10 sub -5 torr range were achieved, the pressure could not be sustained, pressure rose and became erratic. By February 18, 1996, no improvement in the vacuum was observed and it was speculated that there might be a leak in the system. A decision was subsequently made to initiate residual gas analyzer (RGA) scans of the bell jar atmosphere to determine whether the difficulties in achieving the required vacuum were the result of a leak in the system or the outgassing of the converter. The scans obtained revealed the presence of nitrogen, oxygen, and moisture, indicating potential air in-leakage, although various troubleshooting efforts did not reveal the location of any such leak. Subsequent troubleshooting and final replacement of the vacuum system are described.

  20. Lessons from Adaptive Level One Accelerator (ALOA) System Implementation

    NASA Technical Reports Server (NTRS)

    Patel, Umesh D.; Brambora, Clifford; Ghuman, Parminder; Day, John H. (Technical Monitor)

    2001-01-01

    The Adaptive Level One Accelerator (ALOA) system was developed as part of the Earth Science Data and Information System (ESDIS) project. The reconfigurable computing technologies were investigated for Level 1 satellite telemetry data processing to achieve computing acceleration and cost reduction for the next-generation Level 1 data processing systems. The MODIS instrument calibration algorithm was implemented using reconfigurable a computer. The system development process and the lessons learned throughout the design cycle are summarized in this paper.

  1. The molecular branching ratio method for calibration of optical systems in the vacuum ultraviolet

    NASA Technical Reports Server (NTRS)

    Mumma, M. J.

    1972-01-01

    The intensity distribution of bands belonging to six molecular band systems is discussed with special emphasis on their usefulness for intensity calibration of optical systems in the vacuum ultraviolet (1000A Lambda 3000A). The theory of molecular band intensities is outlined and the technique of measuring the spectral response curve is described. Several methods for establishing an absolute intensity calibration are discussed.

  2. Automatic gas-levitation system for vacuum deposition of laser-fusion targets

    SciTech Connect

    Jordan, C.W.; Cameron, G.R.; Krenik, R.M.; Crane, J.K.

    1981-09-08

    An improved simple system has been developed to gas-levitate microspheres during vacuum-deposition processes. The automatic operation relies on two effects: a lateral stabilizing force provided by a centering-ring; and an automatically incremented gas metering system to offset weight increases during coating.

  3. Small system for tritium accelerator mass spectrometry

    DOEpatents

    Roberts, M.L.; Davis, J.C.

    1993-02-23

    Apparatus for ionizing and accelerating a sample containing isotopes of hydrogen and detecting the ratios of hydrogen isotopes contained in the sample is disclosed. An ion source generates a substantially linear ion beam including ions of tritium from the sample. A radio-frequency quadrupole accelerator is directly coupled to and axially aligned with the source at an angle of substantially zero degrees. The accelerator accelerates species of the sample having different mass to different energy levels along the same axis as the ion beam. A spectrometer is used to detect the concentration of tritium ions in the sample. In one form of the invention, an energy loss spectrometer is used which includes a foil to block the passage of hydrogen, deuterium and [sup 3]He ions, and a surface barrier or scintillation detector to detect the concentration of tritium ions. In another form of the invention, a combined momentum/energy loss spectrometer is used which includes a magnet to separate the ion beams, with Faraday cups to measure the hydrogen and deuterium and a surface barrier or scintillation detector for the tritium ions.

  4. Small system for tritium accelerator mass spectrometry

    DOEpatents

    Roberts, Mark L.; Davis, Jay C.

    1993-01-01

    Apparatus for ionizing and accelerating a sample containing isotopes of hydrogen and detecting the ratios of hydrogen isotopes contained in the sample is disclosed. An ion source generates a substantially linear ion beam including ions of tritium from the sample. A radio-frequency quadrupole accelerator is directly coupled to and axially aligned with the source at an angle of substantially zero degrees. The accelerator accelerates species of the sample having different mass to different energy levels along the same axis as the ion beam. A spectrometer is used to detect the concentration of tritium ions in the sample. In one form of the invention, an energy loss spectrometer is used which includes a foil to block the passage of hydrogen, deuterium and .sup.3 He ions, and a surface barrier or scintillation detector to detect the concentration of tritium ions. In another form of the invention, a combined momentum/energy loss spectrometer is used which includes a magnet to separate the ion beams, with Faraday cups to measure the hydrogen and deuterium and a surface barrier or scintillation detector for the tritium ions.

  5. Vacuum Rabi splitting and intracavity dark state in a cavity-atom system

    SciTech Connect

    Hernandez, Gessler; Zhang Jiepeng; Zhu Yifu

    2007-11-15

    We report experimental measurements of the transmission spectrum of an optical cavity coupled with cold Rb atoms. We observe the multiatom vacuum Rabi splitting of a composite cavity and atom system. When a coupling field is applied to the atoms and induces the resonant two-photon Raman transition with the cavity field in a {lambda}-type system, we observe a cavity transmission spectrum with two vacuum Rabi sidebands and a central peak representing the intracavity dark state. The central peak linewidth is significantly narrowed by the dark-state resonance and its position is insensitive to the frequency change of the empty cavity.

  6. Proliferation Potential of Accelerator-Drive Systems: Feasibility Calculations

    SciTech Connect

    Riendeau, C.D.; Moses, D.L.; Olson, A.P.

    1998-11-01

    Accelerator-driven systems for fissile materials production have been proposed and studied since the early 1950s. Recent advances in beam power levels for small accelerators have raised the possibility that such use could be feasible for a potential proliferator. The objective of this study is to review the state of technology development for accelerator-driven spallation neutron sources and subcritical reactors. Energy and power requirements were calculated for a proton accelerator-driven neutron spallation source and subcritical reactors to produce a significant amount of fissile material--plutonium.

  7. Three-grid accelerator system for an ion propulsion engine

    NASA Technical Reports Server (NTRS)

    Brophy, John R. (Inventor)

    1994-01-01

    An apparatus is presented for an ion engine comprising a three-grid accelerator system with the decelerator grid biased negative of the beam plasma. This arrangement substantially reduces the charge-exchange ion current reaching the accelerator grid at high tank pressures, which minimizes erosion of the accelerator grid due to charge exchange ion sputtering, known to be the major accelerator grid wear mechanism. An improved method for life testing ion engines is also provided using the disclosed apparatus. In addition, the invention can also be applied in materials processing.

  8. Design of a tritium-compatible vacuum pumping system for the Compact Ignition Tokamak

    SciTech Connect

    Haines, J.R.

    1987-01-01

    The conceptual design for the Compact Ignition Tokamak (CIT) vacuum pumping system features high-speed, magnetic-bearing turbomolecular pumps (TMPs), metal-sealed scroll pumps for roughing and backing, and all-metal valves and flange seals. Because the plasma chamber exhaust is handled in a throughput instead of hold-up fashion with no organic seal or lubricating materials exposed to the vacuum stream, inventories of tritium, which are vulnerable to release during an accident and which inhibit maintenance of the vacuum pumping equipment, are minimized. To achieve an initial base pressure of 1.3 /times/ 10/sup /minus/6/ Pa in the plasma chamber, the design includes a large vacuum pumping duct and multiple high-speed TMPs arranged in two stages. The design studies discussed in this paper examine the feasibility and cost impact of providing a low-tritium-inventory, easily maintained vacuum pumping system for a deuterium-tritium (D-T) burning tokamak. 7 refs., 3 figs., 2 tabs.

  9. Charged-particle acceleration through laser irradiation of thin foils at Prague Asterix Laser System

    NASA Astrophysics Data System (ADS)

    Torrisi, Lorenzo; Cutroneo, Maria; Cavallaro, Salvatore; Musumeci, Paolo; Calcagno, Lucia; Wolowski, Jerzy; Rosinski, Marcin; Zaras-Szydlowska, Agnieszka; Ullschmied, Jiri; Krousky, Eduard; Pfeifer, Miroslav; Skala, Jiri; Velyhan, Andreiy

    2014-05-01

    Thin foils, 0.5-50 μm in thickness, have been irradiated in vacuum at Prague Asterix Laser System in Prague using 1015-16 W cm-2 laser intensity, 1315 nm wavelength, 300 ps pulse duration and different focal positions. Produced plasmas from metals and polymers films have been monitored in the forward and backward directions. Ion and electron accelerations have been investigated by using Thomson parabola spectrometer, x-ray streak camera, ion collectors and SiC semiconductor detectors, the latter employed in time-of-flight configuration. Ion acceleration up to about 3 MeV per charge state was measured in the forward direction. Ion and electron emissions were detected at different angles as a function of the irradiation conditions.

  10. Accelerated Superposition State Molecular Dynamics for Condensed Phase Systems.

    PubMed

    Ceotto, Michele; Ayton, Gary S; Voth, Gregory A

    2008-04-01

    An extension of superposition state molecular dynamics (SSMD) [Venkatnathan and Voth J. Chem. Theory Comput. 2005, 1, 36] is presented with the goal to accelerate timescales and enable the study of "long-time" phenomena for condensed phase systems. It does not require any a priori knowledge about final and transition state configurations, or specific topologies. The system is induced to explore new configurations by virtue of a fictitious (free-particle-like) accelerating potential. The acceleration method can be applied to all degrees of freedom in the system and can be applied to condensed phases and fluids. PMID:26620930

  11. Techniques for increasing the reliability of accelerator control system electronics

    SciTech Connect

    Utterback, J.

    1993-09-01

    As the physical size of modern accelerators becomes larger and larger, the number of required control system circuit boards increases, and the probability of one of those circuit boards failing while in service also increases. In order to do physics, the experimenters need the accelerator to provide beam reliably with as little down time as possible. With the advent of colliding beams physics, reliability becomes even more important due to the fact that a control system failure can cause the loss of painstakingly produced antiprotons. These facts prove the importance of keeping reliability in mind when designing and maintaining accelerator control system electronics.

  12. Three-dimensional Non-vacuum Pulsar Outer-gap Model: Localized Acceleration Electric Field in the Higher Altitudes

    NASA Astrophysics Data System (ADS)

    Hirotani, Kouichi

    2015-01-01

    We investigate the particle accelerator that arises in a rotating neutron-star magnetosphere. Simultaneously solving the Poisson equation for the electro-static potential, the Boltzmann equations for relativistic electrons and positrons, and the radiative transfer equation, we demonstrate that the electric field is substantially screened along the magnetic field lines by pairs that are created and separated within the accelerator. As a result, the magnetic-field-aligned electric field is localized in higher altitudes near the light cylinder and efficiently accelerates the positrons created in the lower altitudes outward but does not accelerate the electrons inward. The resulting photon flux becomes predominantly outward, leading to typical double-peak light curves, which are commonly observed from many high-energy pulsars.

  13. THREE-DIMENSIONAL NON-VACUUM PULSAR OUTER-GAP MODEL: LOCALIZED ACCELERATION ELECTRIC FIELD IN THE HIGHER ALTITUDES

    SciTech Connect

    Hirotani, Kouichi

    2015-01-10

    We investigate the particle accelerator that arises in a rotating neutron-star magnetosphere. Simultaneously solving the Poisson equation for the electro-static potential, the Boltzmann equations for relativistic electrons and positrons, and the radiative transfer equation, we demonstrate that the electric field is substantially screened along the magnetic field lines by pairs that are created and separated within the accelerator. As a result, the magnetic-field-aligned electric field is localized in higher altitudes near the light cylinder and efficiently accelerates the positrons created in the lower altitudes outward but does not accelerate the electrons inward. The resulting photon flux becomes predominantly outward, leading to typical double-peak light curves, which are commonly observed from many high-energy pulsars.

  14. The SPEAR3 Vacuum System - An Analysis of the First Two Years of Operation (2004 and 2005)

    SciTech Connect

    Armenta, R.; /UCLA

    2005-12-15

    SPEAR 3, a synchrotron radiation source at the Stanford Linear Accelerator Center, has been in operation for the past two years. SPEAR 3 was designed to achieve high beam lifetimes while operating at a higher current level than previously achieved with SPEAR 2. Maintaining high electron beam lifetimes within the ring allows users to perform their experiments with a consistent supply of high current synchrotron radiation. The purpose of this analysis is to evaluate the SPEAR 3 vacuum system's performance during the 2004 and 2005 runs while considering methods to optimize and improve vacuum system conditioning, especially within the pumping system, so that a recommended plan of action can be created for the FY 2006 run. Monitoring the dynamics of the electron beam within the ring can be a difficult task. Pressure data obtained from the gages attached to pumps, temperature data obtained from thermocouples located at various locations around the ring, and beam lifetime projections help to provide some indication of the health of the electron beam, but the true conditions within the beam chamber can only be extrapolated. Data collected from sensors (gauges, thermocouples, etc.) located around the ring can be viewed and extracted from a program created at the Stanford Synchrotron Radiation Laboratory (SSRL) called Historyplot. Manipulation and analysis of data was performed with the commercially available programs Matlab and Excel. The data showed that the beam lifetimes in 2005 were much greater than they were in 2004, but it did not provide a clear indication as to why this occurred. One variable of major importance between the 2004 and 2005 runs is the Titanium Sublimation Pump (TSP) flash frequency (flashing is the process in which Titanium from filaments within the pump is sublimated onto the wall surfaces of the pump, where it removes gas molecules from the system by chemisorption). The data indicated that pressures in 2005 could have been lower, based on a

  15. Cold Vacuum Drying (CVD) Facility General Service Helium System Design Description

    SciTech Connect

    SHAPLEY, B.J.

    2000-04-20

    The purpose of this System Design Description (SDD) is to describe the characteristics of the Cold Vacuum Drying (CVD) Facility general service helium system. The general service helium system is a general service facility process support system, but does include safety-class structures, systems and components (SSCs) providing protection to the offsite public. The general service helium system also performs safety-significant functions that provide protection to onsite workers. The general helium system essential function is to provide helium (He) to support process functions during all phases of facility operations. General service helium is used to purge the cask and the MCO in order to maintain their internal atmospheres below hydrogen flammability concentrations. The general service helium system also supplies helium to purge the process water conditioning (PWC) lines and components and the vacuum purge system (VPS) vacuum pump. The general service helium system, if available following an Safety Class Instrument and Control System (SCIC) Isolation and Purge (IS0 and PURGE) Trip, can provide an alternate general service helium system source to supply the Safety-Class Helium (SCHe) System.

  16. Cold Vacuum Dryer (CVD) Facility Security System Design Description (SYS 54)

    SciTech Connect

    WHITEHURST, R.

    2000-09-11

    This system design description (SDD) addresses the Cold Vacuum Drying (CVD) Facility security system. The system's primary purpose is to provide reasonable assurance that breaches of security boundaries are detected and assessment information is provided to protective force personnel. In addition, the system is utilized by Operations to support reduced personnel radiation goals and to provide reasonable assurance that only authorized personnel are allowed to enter designated security areas.

  17. Cold Vacuum Drying facility fire protection system design description (SYS 24)

    SciTech Connect

    PITKOFF, C.C.

    1999-07-06

    This document describes the Cold Vacuum Drying Facility (CVDF) fire protection system (FPS). The FPS provides fire detection, suppression, and loss limitation for the CVDF structure, personnel, and in-process spent nuclear fuel. The system provides, along with supporting interfacing systems, detection, alarm, and activation instrumentation and controls, distributive piping system, isolation valves, and materials and controls to limit combustibles and the associated fire loadings.

  18. Hyperbolic metamaterial-based near-field thermophotovoltaic system for hundreds of nanometer vacuum gap.

    PubMed

    Jin, Seokmin; Lim, Mikyung; Lee, Seung S; Lee, Bong Jae

    2016-03-21

    Artificially designed hyperbolic metamaterial (HMM) possesses extraordinary electromagnetic features different from those of naturally existing materials. In particular, the dispersion relation of waves existing inside the HMM is hyperbolic rather than elliptical; thus, waves that are evanescent in isotropic media become propagating in the HMM. This characteristic of HMMs opens a novel way to spectrally control the near-field thermal radiation in which evanescent waves in the vacuum gap play a critical role. In this paper, we theoretically investigate the performance of a near-field thermophotovoltaic (TPV) energy conversion system in which a W/SiO2-multilayer-based HMM serves as the emitter at 1000 K and InAs works as the TPV cell at 300 K. By carefully designing the thickness of constituent materials of the HMM emitter, the electric power of the near-field TPV devices can be increased by about 6 times at 100-nm vacuum gap as compared to the case of the plain W emitter. Alternatively, in regards to the electric power generation, HMM emitter at experimentally achievable 100-nm vacuum gap performs equivalently to the plain W emitter at 18-nm vacuum gap. We show that the enhancement mechanism of the HMM emitter is due to the coupled surface plasmon modes at multiple metal-dielectric interfaces inside the HMM emitter. With the minority carrier transport model, the optimal p-n junction depth of the TPV cell has also been determined at various vacuum gaps. PMID:27136882

  19. Application of porcelain enamel as an ultra-high-vacuum-compatible electrical insulator

    SciTech Connect

    Biscardi, C.; Hseuh, H.; Mapes, M.

    2000-07-01

    Many accelerator vacuum system components require electrical insulation internal to the vacuum system. Some accelerator components at Brookhaven National Laboratory are installed in ultra-high-vacuum systems which require the insulation to have excellent vacuum characteristics, be radiation resistant, and be able to withstand high temperatures when used on baked systems. Porcelain enamel satisfies all these requirements. This article describes the process and application of coating metal parts with porcelain enamel to provide electrical insulation. The mechanical and vacuum testing of Marman flanges coated with porcelain and using metal Helicoflex seals to form a zero-length electrical break are detailed. The use of porcelain enameled parts is attractive since it can be done quickly, is inexpensive and environmentally safe, and most of all satisfies stringent vacuum system requirements. (c) 2000 American Vacuum Society.

  20. Vacuum generation in pneumatic artificial heart drives with a specially designed ejector system.

    PubMed

    Schima, H; Huber, L; Spitaler, F

    1990-06-01

    To improve the filling characteristics of pneumatically driven membrane artificial hearts (AHs), a vacuum is applied during diastole. This paper describes an ejector system for AH-drivers based on the Venturi effect, which was designed for this purpose. It provides vacuums of more than -40 mmHg at flow rates up to 50 l/min requiring a supplying primary gas pressure of less than 150 kPa (1140 mmHg). Under normal working conditions, the necessary supply flow was less than 5l/min. The device is small, cheap, quiet and fail-safe, and has been evaluated successfully in experimental and clinical use. PMID:2357149

  1. Low-cost insulation system for cryostats eliminates need for a vacuum

    NASA Technical Reports Server (NTRS)

    Calvert, H. F.

    1964-01-01

    In order to eliminate the hazard caused by residual air trapped between the concentric shells of a cryostat, these annular spaces are pressurized with helium gas. This system is more economical than the use of powdered insulation maintained at low vacuums.

  2. Cold Vacuum Drying facility condensate collection system design description (SYS 19)

    SciTech Connect

    PITKOFF, C.C.

    1999-07-06

    This document describes the Cold Vacuum Drying Facility (CVDF) condensate collection system (CCS). The function of the CCS is to collect cooling coil condensate from air-handling units in the CVDF and to isolate the condensate in collection tanks until the condensate is determined to be acceptable to drain to the effluent drain collection basin.

  3. EVALUATION OF A COMMERCIAL VACUUM SYSTEM FOR THE REMOVAL OF ASBESTOS

    EPA Science Inventory

    The report gives results of a brief field study that included measurement of personal, area, and environmental asbestos exposures resulting from wet and dry asbestos removal using a commercial vacuum system. Personal and area (indoor) asbestos concentrations during dry removal we...

  4. Preliminary safety evaluation for the spent nuclear fuel project`s cold vacuum drying system

    SciTech Connect

    Garvin, L.J., Westinghouse Hanford

    1996-07-01

    This preliminary safety evaluation (PSE) considers only the Cold Vacuum Drying System (CVDS) facility and its mission as it relates to the integrated process strategy (WHC 1995). The purpose of the PSE is to identify those CBDS design functions that may require safety- class and safety-significant accident prevention and mitigation features.

  5. Failure Mode Effects Analysis for an Accelerator Control System

    SciTech Connect

    Hartman, Steven M

    2009-01-01

    Failure mode effects analysis (FMEA) has been used in industry for design, manufacturing and assembly process quality control. It describes a formal approach for categorizing how a process may fail and for prioritizing failures based on their severity, frequency and likelihood of detection. Experience conducting a partial FMEA of an accelerator subsystem and its related control system will be reviewed. The applicability of the FMEA process to an operational accelerator control system will be discussed.

  6. PTC-6 vacuum system: WallWalker{trademark} and Blastrac{reg_sign} shot blast cleaning system

    SciTech Connect

    1998-02-01

    The LTC Americas, Inc. wall decontamination technology consisted of two pneumatic hand-held tools: (1) a roto-peen scaler that used star cutters and (2) a 3-piston hammer with reciprocating bits. The hand-held tools were used in conjunction with the LTC PTC-6 vacuum system which captured dust and debris as the wall decontamination took place. Recommendations for improved worker safety and health during use of the PTC-6 vacuum system with hand-held tools include: (1) keeping all hoses and lines as orderly as possible in compliance with good housekeeping requirements; (2) ergonomic training to include techniques in lifting, bending, stooping, twisting, etc.; (3) use of a clamping system to hold hoses to the vacuum system; (4) a safety line on the air line connections; (5) use of a mechanical lifting system for waste drum removal; and (6) the use of ergonomically designed tools.

  7. Cold Vacuum Drying facility civil structural system design description (SYS 06)

    SciTech Connect

    PITKOFF, C.C.

    1999-07-06

    This document describes the Cold Vacuum Drying (CVD) Facility civil - structural system. This system consists of the facility structure, including the administrative and process areas. The system's primary purpose is to provide for a facility to house the CVD process and personnel and to provide a tertiary level of containment. The document provides a description of the facility and demonstrates how the design meets the various requirements imposed by the safety analysis report and the design requirements document.

  8. Cold Vacuum Drying facility deionized water system design description (SYS 25)

    SciTech Connect

    PITKOFF, C.C.

    1999-07-02

    This document describes the Cold Vacuum Drying Facility (CVDF) de-ionized water system. The de-ionized water system is used to provide clean, conditioned water, free from contaminants, chlorides and iron for the CVD Facility. Potable water is supplied to the deionized water system, isolated by a backflow prevention device. After the de-ionization process is complete, via a packaged de-ionization unit, de-ionized water is supplied to the process deionization unit.

  9. Night vision imaging system design, integration and verification in spacecraft vacuum thermal test

    NASA Astrophysics Data System (ADS)

    Shang, Yonghong; Wang, Jing; Gong, Zhe; Li, Xiyuan; Pei, Yifei; Bai, Tingzhu; Zhen, Haijing

    2015-08-01

    The purposes of spacecraft vacuum thermal test are to characterize the thermal control systems of the spacecraft and its component in its cruise configuration and to allow for early retirement of risks associated with mission-specific and novel thermal designs. The orbit heat flux is simulating by infrared lamp, infrared cage or electric heater. As infrared cage and electric heater do not emit visible light, or infrared lamp just emits limited visible light test, ordinary camera could not operate due to low luminous density in test. Moreover, some special instruments such as satellite-borne infrared sensors are sensitive to visible light and it couldn't compensate light during test. For improving the ability of fine monitoring on spacecraft and exhibition of test progress in condition of ultra-low luminous density, night vision imaging system is designed and integrated by BISEE. System is consist of high-gain image intensifier ICCD camera, assistant luminance system, glare protect system, thermal control system and computer control system. The multi-frame accumulation target detect technology is adopted for high quality image recognition in captive test. Optical system, mechanical system and electrical system are designed and integrated highly adaptable to vacuum environment. Molybdenum/Polyimide thin film electrical heater controls the temperature of ICCD camera. The results of performance validation test shown that system could operate under vacuum thermal environment of 1.33×10-3Pa vacuum degree and 100K shroud temperature in the space environment simulator, and its working temperature is maintains at 5° during two-day test. The night vision imaging system could obtain video quality of 60lp/mm resolving power.

  10. Acceleration of electrons by a circularly polarized laser pulse in the presence of an intense axial magnetic field in vacuum

    SciTech Connect

    Singh, K. P.

    2006-08-15

    Acceleration of electrons by a circularly polarized laser pulse in the presence of a short duration intense axial magnetic field has been studied. Resonance occurs between the electrons and the laser field for an optimum magnetic field leading to effective energy transfer from laser to electrons. The value of optimum magnetic field is independent of the laser intensity and decreases with initial electron energy. The electrons rotate around the axis of the laser pulse with small angle of emittance and small energy spread. Acceleration gradient increases with laser intensity and decreases with initial electron energy.

  11. Remote vacuum or pressure sealing device and method for critical isolated systems

    DOEpatents

    Brock, James David; Keith, Christopher D.

    2012-07-10

    A remote vacuum or pressure sealing apparatus and method for making a radiation tolerant, remotely prepared seal that maintains a vacuum or pressure tight seal throughout a wide temperature range. The remote sealing apparatus includes a fixed threaded sealing surface on an isolated system, a gasket, and an insert consisting of a plug with a protruding sample holder. An insert coupling device, provided for inserting samples within the isolated system, includes a threaded fastener for cooperating with the fixed threaded sealing surface on the isolated system. The insert coupling device includes a locating pin for azimuthal orientation, coupling pins, a tooted coaxial socket wrench, and an insert coupling actuator for actuating the coupling pins. The remote aspect of the sealing apparatus maintains the isolation of the system from the user's environment, safely preserving the user and the system from detrimental effect from each respectively.

  12. Natural vacuum electronics

    NASA Technical Reports Server (NTRS)

    Leggett, Nickolaus

    1990-01-01

    The ambient natural vacuum of space is proposed as a basis for electron valves. Each valve is an electron controlling structure similiar to a vacuum tube that is operated without a vacuum sustaining envelope. The natural vacuum electron valves discussed offer a viable substitute for solid state devices. The natural vacuum valve is highly resistant to ionizing radiation, system generated electromagnetic pulse, current transients, and direct exposure to space conditions.

  13. Accelerator control system at KEKB and the linac

    NASA Astrophysics Data System (ADS)

    Akiyama, Atsuyoshi; Furukawa, Kazuro; Kadokura, Eiichi; Kurashina, Miho; Mikawa, Katsuhiko; Nakamura, Tatsuro; Odagiri, Jun-ichi; Satoh, Masanori; Suwada, Tsuyoshi

    2013-03-01

    KEKB has completed all of the technical milestones and has offered important insights into the flavor structure of elementary particles, especially CP violation. The accelerator control system at KEKB and the injector linac was initiated by a combination of scripting languages at the operation layer and EPICS (experimental physics and industrial control system) at the equipment layer. During the project, many features were implemented to achieve extreme performance from the machine. In particular, the online linkage to the accelerator simulation played an essential role. In order to further improve the reliability and flexibility, two major concepts were additionally introduced later in the project, namely, channel access everywhere and dual-tier controls. Based on the improved control system, a virtual accelerator concept was realized, allowing the single injector linac to serve as three separate injectors to KEKB's high-energy ring, low-energy ring, and Photon Factory, respectively. These control technologies are indispensable for future particle accelerators.

  14. Optimizing process vacuum condensers

    SciTech Connect

    Lines, J.R.; Tice, D.W.

    1997-09-01

    Vacuum condensers play a critical role in supporting vacuum processing operations. Although they may appear similar to atmospheric units, vacuum condensers have their own special designs, considerations and installation needs. By adding vacuum condensers, precondensers and intercondensers, system cost efficiency can be optimized. Vacuum-condensing systems permit reclamation of high-value product by use of a precondenser, or reduce operating costs with intercondensers. A precondenser placed between the vacuum vessel and ejector system will recover valuable process vapors and reduce vapor load to an ejector system--minimizing the system`s capital and operating costs. Similarly, an intercondenser positioned between ejector stages can condense motive steam and process vapors and reduce vapor load to downstream ejectors as well as lower capital and operating costs. The paper describes vacuum condenser systems, types of vacuum condensers, shellside condensing, tubeside condensing, noncondensable gases, precondenser pressure drop, system interdependency, equipment installation, and equipment layout.

  15. Integration of LHCD system with SST1 machine and its high power rf performance in vacuum

    NASA Astrophysics Data System (ADS)

    Sharma, P. K.; Ambulkar, K. K.; Dalakoti, S.; Parmar, P. R.; Virani, C. G.; Thakur, A. L.

    2014-02-01

    A 2.0 MW CW lower hybrid current drive (LHCD) system based on 3.7 GHz klystron sources, is in advanced stage of commissioning, which would drive and sustain plasma current, non-inductively, in superconducting steadystate tokamak (SST1) for long pulse operation. Four klystrons, each rated for 0.5 MW CW rf power, delivers 2.0 MW of rf power to four layer of the LHCD system, which finally feeds the rf power to grill antenna. The antenna system along with vacuum window and vacuum transmission line is successfully integrated on the machine. Its vacuum and pressurization compatibility has been successfully established. To validate the high power performance of LHCD system for SST1 machine, stage-wise commissioning of LHCD system in staggered manner is planned. It has been envisaged that LHCD power may be gradually increased initially, since full power may not be required during the initial phases of SST1 plasma operation. Also if the system is integrated in steps or in phases, then integration issues, as well as high power operational issues, if any, can be addressed, attended and handled in a simpler way before integrating all the layers to the grill antenna. To begin with, one klystron is connected to one layer, out of four layers, which energizes a quarter of the grill antenna. Gradually, the rf power and its pulse length is increased to validate high power performance of the system. Arcing and reflections are observed as rf power is gradually increased. The problems are analysed and after taking appropriate remedial action the system performance is improved for operation up to 160kW. Several trains of short pulses are launched in SST1 vacuum vessel for rf conditioning of the LHCD system. Normally, reflections are high when power is launched in vacuum; therefore the pulse length is restricted up to 100 milliseconds. The high power performance of this layer, connected with grill antenna is validated by launching high power microwaves in vacuum vessel of SST1 machine

  16. Design and Construction of the NSTX Bakeout, Cooling and Vacuum Systems

    SciTech Connect

    L.E. Dudek; M. Kalish; R. Gernhardt; R.F. Parsells; W. Blanchard

    1999-11-01

    This paper will describe the design, construction and initial operation of the NSTX bakeout, water cooling and vacuum systems. The bakeout system is designed for two modes of operation. The first mode allows heating of the first wall components to 350 degrees C while the external vessel is cooled to 150 degrees C. The second mode cools the first wall to 150 degrees C and the external vessel to 50 degrees C. The system uses a low viscosity heat transfer oil which is capable of high temperature low pressure operation. The NSTX Torus Vacuum Pumping System (TVPS) is designed to achieve a base pressure of approximately 1x10 (superscript -8) Torr and to evacuate the plasma fuel gas loads in less than 5 minutes between discharges. The vacuum pumping system is capable of a pumping speed of approximately 3400 l/s for deuterium. The hardware consists of two turbo molecular pumps (TMPs) and a mechanical pump set consisting of a mechanical and a Roots blower pump. A PLC is used as the control system to provide remote monitoring, control and software interlock capability. The NSTX cooling water provides chilled, de ionized water for heat removal in the TF, OH and PF, power supplies, bus bar systems, and various diagnostics. The system provides flow monitoring via a PLC to prevent damage due to loss of flow.

  17. Comparative emissions of random orbital sanding between conventional and self-generated vacuum systems.

    PubMed

    Liverseed, David R; Logan, Perry W; Johnson, Carl E; Morey, Sandy Z; Raynor, Peter C

    2013-03-01

    Conventional abrasive sanding generates high concentrations of particles. Depending on the substrate being abraded and exposure duration, overexposure to the particles can cause negative health effects ranging from respiratory irritation to cancer. The goal of this study was to understand the differences in particle emissions between a conventional random orbital sanding system and a self-generated vacuum random orbital sanding system with attached particle filtration bag. Particle concentrations were sampled for each system in a controlled test chamber for oak wood, chromate painted (hexavalent chromium) steel panels, and gel-coated (titanium dioxide) fiberglass panels using a Gesamtstaub-Probenahmesystem (GSP) sampler at three different locations adjacent to the sanding. Elevated concentrations were reported for all particles in the samples collected during conventional sanding. The geometric mean concentration ratios for the three substrates ranged from 320 to 4640 times greater for the conventional sanding system than the self-generated vacuum sanding system. The differences in the particle concentration generated by the two sanding systems were statistically significant with the two sample t-test (P < 0.0001) for all three substances. The data suggest that workers using conventional sanding systems could utilize the self-generated vacuum sanding system technology to potentially reduce exposure to particles and mitigate negative health effects. PMID:23065674

  18. Comparative Emissions of Random Orbital Sanding between Conventional and Self-Generated Vacuum Systems

    PubMed Central

    Liverseed, David R.

    2013-01-01

    Conventional abrasive sanding generates high concentrations of particles. Depending on the substrate being abraded and exposure duration, overexposure to the particles can cause negative health effects ranging from respiratory irritation to cancer. The goal of this study was to understand the differences in particle emissions between a conventional random orbital sanding system and a self-generated vacuum random orbital sanding system with attached particle filtration bag. Particle concentrations were sampled for each system in a controlled test chamber for oak wood, chromate painted (hexavalent chromium) steel panels, and gel-coated (titanium dioxide) fiberglass panels using a Gesamtstaub-Probenahmesystem (GSP) sampler at three different locations adjacent to the sanding. Elevated concentrations were reported for all particles in the samples collected during conventional sanding. The geometric mean concentration ratios for the three substrates ranged from 320 to 4640 times greater for the conventional sanding system than the self-generated vacuum sanding system. The differences in the particle concentration generated by the two sanding systems were statistically significant with the two sample t-test (P < 0.0001) for all three substances. The data suggest that workers using conventional sanding systems could utilize the self-generated vacuum sanding system technology to potentially reduce exposure to particles and mitigate negative health effects. PMID:23065674

  19. Open loop, auto reversing liquid nitrogen circulation thermal system for thermo vacuum chamber

    NASA Astrophysics Data System (ADS)

    Naidu, M. C. A.; Nolakha, Dinesh; Saharkar, B. S.; Kavani, K. M.; Patel, D. R.

    2012-11-01

    In a thermo vacuum chamber, attaining and controlling low and high temperatures (-100 Deg. C to +120 Deg. C) is a very important task. This paper describes the development of "Open loop, auto reversing liquid nitrogen based thermal system". System specifications, features, open loop auto reversing system, liquid nitrogen flow paths etc. are discussed in this paper. This thermal system consists of solenoid operated cryogenic valves, double embossed thermal plate (shroud), heating elements, temperature sensors and PLC. Bulky items like blowers, heating chambers, liquid nitrogen injection chambers, huge pipe lines and valves were not used. This entire thermal system is very simple to operate and PLC based, fully auto system with auto tuned to given set temperatures. This system requires a very nominal amount of liquid nitrogen (approx. 80 liters / hour) while conducting thermo vacuum tests. This system was integrated to 1.2m dia thermo vacuum chamber, as a part of its augmentation, to conduct extreme temperature cycling tests on passive antenna reflectors of satellites.

  20. Ultra-high vacuum system of the Brookhaven National Synchrotron Light Source

    SciTech Connect

    Foerster, C.L.

    1995-12-31

    The rings of the National Synchrotron Light Source (NSLS) have been supplying light to numerous users for approximately a decade and we recently enjoyed a fully conditioned machine vacuum at design currents. A brief description of the X-Ray storage ring, the VUV storage ring and their current supply is given along with some of their features. The ultra-high vacuum system employed for the storage rings and their advantages for the necessary stored beam environments are discussed including, a brief history of time. After several hundred amp hours of stored beam current operation, very little improvement in machine performance was seen due to conditioning. Sections of the rings were vented, to dry nitrogen and replacement components were pre-baked and pre-argon glow conditioned prior to installation. Very little machine conditioning was needed to return to operation after recovering vacuum due to well established conditioning procedures. All straight sections in the X-Ray ring and the VUV ring have been filled with various insertion devices and most are fully operational. Each storage ring has a computer controlled total pressure and partial pressure monitoring system for the ring and its beam ports, to insure good vacuum.

  1. COMPACT PROTON INJECTOR AND FIRST ACCELERATOR SYSTEM TEST FOR COMPACT PROTON DIELECTRIC WALL CANCER THERAPY ACCELERATOR

    SciTech Connect

    Chen, Y; Guethlein, G; Caporaso, G; Sampayan, S; Blackfield, D; Cook, E; Falabella, S; Harris, J; Hawkins, S; Nelson, S; Poole, B; Richardson, R; Watson, J; Weir, J; Pearson, D

    2009-04-23

    A compact proton accelerator for cancer treatment is being developed by using the high-gradient dielectric insulator wall (DWA) technology [1-4]. We are testing all the essential DWA components, including a compact proton source, on the First Article System Test (FAST). The configuration and progress on the injector and FAST will be presented.

  2. Impurity control and vacuum pumping system design and analysis for next-generation tokamaks

    SciTech Connect

    Haines, J.R.

    1985-01-01

    Impurity control system design and performance studies were performed in support of the Tokamak Fusion Core Experiment (TFCX) preconceptual design. Efforts concentrated on the pumped limiter and vacuum pumping system design configuration, thermal/mechanical and erosion lifetime performance of the limiter protective surface, and helium ash removal performance. Analysis results indicate that the limiter/vacuum pumping system design provides marginally adequate helium ash removal. Difficulties in providing adequate helium ash removal for more compact or higher fusion-power-density devices are addressed. Erosion, primarily by disruption-induced vaporization and/or melting, limits the protective surface lifetime to about one calendar year or only about 60 full power hours of operation. In addition to evaluating impurity control system performance for nominal TFCX conditions, these studies attempt to focus on the key plasma physics and engineering design issues that should be addressed in future research and development programs.

  3. Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy Studies on Processed Tooth Graft Material by Vacuum-ultrasonic Acceleration

    PubMed Central

    Lee, Eun-Young; Kim, Eun-Suk; Kim, Kyung-Won

    2014-01-01

    Purpose: The current gold standard for clinical jawbone formation involves autogenous bone as a graft material. In addition, demineralized dentin can be an effective graft material. Although demineralized dentin readily induces heterotopic bone formation, conventional decalcification takes three to five days, so, immediate bone grafting after extraction is impossible. This study evaluated the effect of vacuum ultrasonic power on the demineralization and processing of autogenous tooth material and documented the clinical results of rapidly processed autogenous demineralized dentin (ADD) in an alveolar defects patient. Methods: The method involves the demineralization of extracted teeth with detached soft tissues and pulp in 0.6 N HCl for 90 minutes using a heat controlled vacuum-ultrasonic accelerator. The characteristics of processed teeth were evaluated by scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). Bone grafting using ADD was performed for narrow ridges augmentation in the mandibular area. Results: The new processing method was completed within two hours regardless of form (powder or block). EDS and SEM uniformly demineralized autotooth biomaterial. After six months, bone remodeling was observed in augmented sites and histological examination showed that ADD particles were well united with new bone. No unusual complications were encountered. Conclusion: This study demonstrates the possibility of preparing autogenous tooth graft materials within two hours, allowing immediate one-day grafting after extraction. PMID:27489819

  4. RFQ design for the RAON accelerator's ISOL system

    NASA Astrophysics Data System (ADS)

    Choi, Bong Hyuk; Hong, In-Seok

    2015-10-01

    The heavy-ion accelerator RAON has the advantage of having both an in-flight (IF) and an isotope separator on-line (ISOL) system. Two radio frequency quadrupoles (RFQs) will be installed in the RAON: the main linear accelerator (LINAC) RFQ will be used to accelerate the two-charge state 238U for the IF system, while the post-accelerator RFQ will be used to accelerate low-current isotope beams from the ISOL system. In this paper, the post-accelerator RFQ design for the ISOL system is reported. A beam current of 1 pμA was used, and the input beam and the output beam energies were 5 keV/u and 400 keV/u, respectively. Moreover, the design was optimized by reducing the total length and power, adjusting the beam quality. To quantify the influence of thermal expansion on the frequency, we calculated the frequency difference according to deference between the vane's tip and the body's diameter.

  5. Mass independent kinetic energy reducing inlet system for vacuum environment

    DOEpatents

    Reilly, Peter T. A. [Knoxville, TN

    2010-12-14

    A particle inlet system comprises a first chamber having a limiting orifice for an incoming gas stream and a micrometer controlled expansion slit. Lateral components of the momentum of the particles are substantially cancelled due to symmetry of the configuration once the laminar flow converges at the expansion slit. The particles and flow into a second chamber, which is maintained at a lower pressure than the first chamber, and then moves into a third chamber including multipole guides for electromagnetically confining the particle. The vertical momentum of the particles descending through the center of the third chamber is minimized as an upward stream of gases reduces the downward momentum of the particles. The translational kinetic energy of the particles is near-zero irrespective of the mass of the particles at an exit opening of the third chamber, which may be advantageously employed to provide enhanced mass resolution in mass spectrometry.

  6. Mass independent kinetic energy reducing inlet system for vacuum environment

    DOEpatents

    Reilly, Peter T.A.

    2014-05-13

    A particle inlet system comprises a first chamber having a limiting orifice for an incoming gas stream and a micrometer controlled expansion slit. Lateral components of the momentum of the particles are substantially cancelled due to symmetry of the configuration once the laminar flow converges at the expansion slit. The particles and flow into a second chamber, which is maintained at a lower pressure than the first chamber, and then moves into a third chamber including multipole guides for electromagnetically confining the particle. The vertical momentum of the particles descending through the center of the third chamber is minimized as an upward stream of gases reduces the downward momentum of the particles. The translational kinetic energy of the particles is near-zero irrespective of the mass of the particles at an exit opening of the third chamber, which may be advantageously employed to provide enhanced mass resolution in mass spectrometry.

  7. Mass independent kinetic energy reducing inlet system for vacuum environment

    DOEpatents

    Reilly, Peter T.A.

    2013-12-03

    A particle inlet system comprises a first chamber having a limiting orifice for an incoming gas stream and a micrometer controlled expansion slit. Lateral components of the momentum of the particles are substantially cancelled due to symmetry of the configuration once the laminar flow converges at the expansion slit. The particles and flow into a second chamber, which is maintained at a lower pressure than the first chamber, and then moves into a third chamber including multipole guides for electromagnetically confining the particle. The vertical momentum of the particles descending through the center of the third chamber is minimized as an upward stream of gases reduces the downward momentum of the particles. The translational kinetic energy of the particles is near-zero irrespective of the mass of the particles at an exit opening of the third chamber, which may be advantageously employed to provide enhanced mass resolution in mass spectrometry.

  8. Project W-320 high vacuum 241-AY-102 annulus ventilation system operability test report

    SciTech Connect

    Bailey, J.W.

    1998-03-12

    This report documents the test results of OTP-320-001, Tank 241-AY-102 Annulus Ventilation System Testing. Included in the appendices are: (1) Supporting documentation prepared to demonstrate the structural integrity of the tank at high annulus vacuum (<20 INWG), and (2) a report that identifies potential cross connections between the primary and annulus ventilation systems. These cross connections were verified to be eliminated prior to the start of testing.

  9. Cold Vacuum Drying facility crane and hoist system design description (SYS 14)

    SciTech Connect

    PITKOFF, C.C.

    1999-07-06

    This document describes the Cold Vacuum Drying Facility (CVDF) crane and hoist system. The overhead crane and hoist system is located in the process bays of the CVDF. It supports the processes required to drain the water and dry the spent nuclear fuel contained in the multi-canister overpacks after they have been removed from the K-Basins. The cranes will also be used to assist maintenance activities within the bays, as required.

  10. Optical system for measurement of pyrotechnic test accelerations

    NASA Astrophysics Data System (ADS)

    Lieberman, Paul; Czajkowski, John; Rehard, John

    1992-12-01

    This effort was directed at comparing the response of several different accelerometer and amplifier combinations to the pyrotechnic pulse simulating the ordnance separation of stages of multistage missiles. These pyrotechnic events can contain peak accelerations in excess of 100,000 G and a frequency content exceeding 100,000 Hz. The main thrust of this work was to compare the several accelerometer systems with each other and with a very accurate laser Doppler displacement meter in order to establish the frequency bands and acceleration amplitudes where the accelerometer systems are in error. The comparisons were made in simple sine-wave and low-acceleration amplitude environments, as well as in very severe pyroshock environments. An optical laser Doppler displacement meter (LDDM) was used to obtain the displacement velocity and acceleration histories, as well as the corresponding shock spectrum.

  11. A new tool for accelerator system modeling and analysis

    SciTech Connect

    Gillespie, G.H.; Hill, B.W.; Jameson, R.A.

    1994-09-01

    A novel computer code is being developed to generate system level designs of radiofrequency ion accelerators. The goal of the Accelerator System Model (ASM) code is to create a modeling and analysis tool that is easy to use, automates many of the initial design calculations, supports trade studies used in assessing alternate designs and yet is flexible enough to incorporate new technology concepts as they emerge. Hardware engineering parameters and beam dynamics are modeled at comparable levels of fidelity. Existing scaling models of accelerator subsystems were sued to produce a prototype of ASM (version 1.0) working within the Shell for Particle Accelerator Related Codes (SPARC) graphical user interface. A small user group has been testing and evaluating the prototype for about a year. Several enhancements and improvements are now being developed. The current version (1.1) of ASM is briefly described and an example of the modeling and analysis capabilities is illustrated.

  12. Design and operation of the Rover vacuum system

    SciTech Connect

    Wagner, E.P. Jr.; Griffith, D.L.; Rivera, J.M.

    1997-08-01

    The Rover process for recovering unused uranium from graphite fuels was operated during 1983 and 1984, and then shut down in 1984. The first steps of the process used fluidized alumina beds to burn away the graphite and produce a uranium bearing ash. The ash was then transferred to a different process cell for acid dissolution. At the time of shutdown, a significant, but unmeasureable, quantity of highly enriched uranium was left in the process vessels. Normal decontamination procedures could not be used due to plugged process lines and the exclusion of moderator materials (water or finely divided organic substances) for criticality safety. The presence of highly enriched uranium in poorly defined quantity and configuration led to concerns for criticality safety, nuclear materials accountability, and physical security. A project was established to eliminate these concerns by cleaning and/or removing the process vessels, piping, and cells and sending the recovered Uranium Bearing Material (UBM) to secure storage. A key element of this project was the design of a system for collecting and transporting dry solids to a location where they could be loaded into critically favorable storage cans.

  13. Two-stage flow-dividing system for the calibration of vacuum gauges

    SciTech Connect

    Yoshida, Hajime; Arai, Kenta; Akimichi, Hitoshi; Hirata, Masahiro

    2008-01-15

    A two-stage flow-dividing system was developed for calibrating an ionization gauge (IG) and residual gas analyzer (RGA). This system generates a stable high and ultrahigh vacuum from 8x10{sup -3} to 2x10{sup -7} Pa by adjusting the pressure in the first chamber using N{sub 2}, Ar, He, and H{sub 2}. The calibration pressure in the third chamber is calculated from the pressure in the second chamber using their linear relation in molecular flow. The uncertainty of the generated pressure was comparable to or several times larger than that of the continuous-expansion system. However, this system has a simple configuration and is easy to operate compared with the continuous-expansion system because it has no moving parts. Results of the calibration of IG and RGA showed that the two-stage flow-dividing system is useful for a routine calibration of practical vacuum gauges in high and ultrahigh vacuum.

  14. Field-Analysis of Vacuum Free-Space LaserAcceleration from Rough-Surface and Absorbing Thin Boundaries

    SciTech Connect

    Plettner, Thomas; /Stanford U., Ginzton Lab.

    2008-06-02

    This script presents a field-based analysis of laser acceleration of relativistic electrons in a free space that is bounded by a thin scattering or by a thin absorbing surface. The laser acceleration process is analyzed in terms of the inverse-radiation formalism and compared to the more familiar field path-integral analysis method. When the scattering boundary is modeled as a linear-index medium the predictions for laser-electron interactions from both field methods are found to agree. For the absorbing boundary both interaction pictures are also found to agree provided that the inverse radiation method is generalized to include absorption of energy from the boundary that is modeled as a linear ohmic-loss object.

  15. ISABELLE accelerator software, control system, and beam diagnostic philosophy

    SciTech Connect

    Cornacchia, M.; Humphrey, J.W.; Niederer, J.; Poole, J.H.

    1981-01-01

    The ISABELLE Project combines two large proton accelerators with two storage rings in the same facility using superconducting magnet technology. This combination leads to severe constraints on beam loss in magnets and involves complex treatment of magnetic field imperfections and correction elements. The consequent demands placed upon beam diagnostics, accelerator model programs, and the computer oriented control system are discussed in terms of an illustrative operation scenario.

  16. Compact all-fiber interferometer system for shock acceleration measurement

    NASA Astrophysics Data System (ADS)

    Zhao, Jiang; Pi, Shaohua; Hong, Guangwei; Zhao, Dong; Jia, Bo

    2013-08-01

    Acceleration measurement plays an important role in a variety of fields in science and engineering. In particular, the accurate, continuous and non-contact recording of the shock acceleration profiles of the free target surfaces is considered as a critical technique in shock physics. Various kinds of optical interferometers have been developed to monitor the motion of the surfaces of shocked targets since the 1960s, for instance, the velocity interferometer system for any reflector, the fiber optic accelerometer, the photonic Doppler velocimetry system and the displacement interferometer. However, most of such systems rely on the coherent quasi-monochromatic illumination and discrete optic elements, which are costly in setting-up and maintenance. In 1996, L. Levin et al reported an interferometric fiber-optic Doppler velocimeter with high-dynamic range, in which fiber-coupled components were used to replace the discrete optic elements. However, the fringe visibility of the Levin's system is low because of the coupled components, which greatly limits the reliability and accuracy in the shock measurement. In this paper, a compact all-fiber interferometer system for measuring the shock acceleration is developed and tested. The advantage of the system is that not only removes the non-interfering light and enhances the fringe visibility, but also reduces polarization induced signal fading and the polarization induced phase shift. Moreover, it also does not require a source of long coherence length. The system bases entirely on single-mode fiber optics and mainly consists of a polarization beam splitter, a faraday rotator, a depolarizer and a 3×3 single-mode fiber coupler which work at 1310 nm wavelength. The optical systems of the interferometer are described and the experimental results compared with a shock acceleration calibration system with a pneumatic exciter (PneuShockTM Model 9525C by The Modal Shop) are reported. In the shock acceleration test, the

  17. An accelerated forth data-acquisition system

    NASA Technical Reports Server (NTRS)

    Bowhill, S. A.; Rennier, A. D.

    1986-01-01

    A new data acquisition system was put into operation at Urbana in August 1984. It uses a standard Apple 2 microcomputer with 48 k RAM and a standard 5 1/4 inch floppy disk. Design criteria for the system is given. The system was implemented using fig-FORTH, a threaded interpretive language which permits easy interfacing to machine code. The throughput of this system is better by a factor of 6 than the PDP-15 minicomputer system previously used, and it has the real time display feature and provides the data in much more convenient form. The features which contribute to this improved performance is listed.

  18. Photon reflectivity distributions from the LHC beam screen and their implications on the arc beam vacuum system

    NASA Astrophysics Data System (ADS)

    Mahne, N.; Baglin, V.; Collins, I. R.; Giglia, A.; Pasquali, L.; Pedio, M.; Nannarone, S.; Cimino, R.

    2004-07-01

    In particle accelerators with intense positively charged bunched beams, an electron cloud may induce beam instabilities and the related beam induced electron multipacting (BIEM) can result in an undesired pressure rise. In a cryogenic machine such as the large hadron collider (LHC), the BIEM will introduce additional heat load. When present, synchrotron radiation (SR) may generate a significant number of photoelectrons, that may play a role in determining the onset and the detailed properties of the electron cloud related instability. Since electrons are constrained to move along field lines, those created on the accelerator equator in a strong vertical (dipole) field cannot participate in the e-cloud build-up. Therefore, for the LHC there has been a continuous effort to find solutions to absorb the photons on the equator. The solution adopted for the LHC dipole beam screens is a saw-tooth structure on the illuminated equator. SR from a bending magnet beamline at ELETTRA, Italy (BEAR) has been used to measure the reflectivities (forward, back-scattered and diffuse), for a flat and a saw-tooth structured Cu co-laminated surface using both white light SR, similar to the one emitted by LHC, and monochromatic light. Our data show that the saw-tooth structure does reduce the total reflectivity and modifies the photon energy distribution of the reflected photons. The implications of these results on the LHC arc vacuum system are discussed.

  19. Note: A simple sample transfer alignment for ultra-high vacuum systems

    NASA Astrophysics Data System (ADS)

    Tamtögl, A.; Carter, E. A.; Ward, D. J.; Avidor, N.; Kole, P. R.; Jardine, A. P.; Allison, W.

    2016-06-01

    The alignment of ultra-high-vacuum sample transfer systems can be problematic when there is no direct line of sight to assist the user. We present the design of a simple and cheap system which greatly simplifies the alignment of sample transfer devices. Our method is based on the adaptation of a commercial digital camera which provides live views from within the vacuum chamber. The images of the camera are further processed using an image recognition and processing code which determines any misalignments and reports them to the user. Installation has proven to be extremely useful in order to align the sample with respect to the transfer mechanism. Furthermore, the alignment software can be easily adapted for other systems.

  20. Development of a wireless displacement measurement system using acceleration responses.

    PubMed

    Park, Jong-Woong; Sim, Sung-Han; Jung, Hyung-Jo; Spencer, Billie F

    2013-01-01

    Displacement measurements are useful information for various engineering applications such as structural health monitoring (SHM), earthquake engineering and system identification. Most existing displacement measurement methods are costly, labor-intensive, and have difficulties particularly when applying to full-scale civil structures because the methods require stationary reference points. Indirect estimation methods converting acceleration to displacement can be a good alternative as acceleration transducers are generally cost-effective, easy to install, and have low noise. However, the application of acceleration-based methods to full-scale civil structures such as long span bridges is challenging due to the need to install cables to connect the sensors to a base station. This article proposes a low-cost wireless displacement measurement system using acceleration. Developed with smart sensors that are low-cost, wireless, and capable of on-board computation, the wireless displacement measurement system has significant potential to impact many applications that need displacement information at multiple locations of a structure. The system implements an FIR-filter type displacement estimation algorithm that can remove low frequency drifts typically caused by numerical integration of discrete acceleration signals. To verify the accuracy and feasibility of the proposed system, laboratory tests are carried out using a shaking table and on a three storey shear building model, experimentally confirming the effectiveness of the proposed system. PMID:23881123

  1. Compact ultrahigh vacuum/high-pressure system for broadband infrared sum frequency generation vibrational spectroscopy studies

    NASA Astrophysics Data System (ADS)

    Liu, Shuo; Liu, An-an; Zhang, Ruidan; Ren, Zefeng

    2016-04-01

    We have designed a compact ultrahigh vacuum/high-pressure system for in situ broadband infrared (IR) sum frequency generation vibrational spectroscopy (SFG-VS) studies. In this system, we have achieved a significant reduction in the distance between the sample and the optical window (<5 mm), which in turn considerably reduces the IR absorption from the gas phase under high pressure conditions. Moreover, with this new system, the IR transmission under high pressure conditions can be measured in situ for calibrating the SFG spectra. Therefore, this modified technique can allow us to study the vibrational spectra of adsorbates on single crystals or polycrystalline foils under high pressure. The preliminary results from SFG measurements of a model CH3OH/TiO2(110) system under both ultrahigh vacuum and high pressure conditions are reported here. These results suggest that this newly developed system is potentially a powerful tool for investigating adsorbate structures and surface reactions under both ultrahigh vacuum and real conditions.

  2. Compact ultrahigh vacuum/high-pressure system for broadband infrared sum frequency generation vibrational spectroscopy studies.

    PubMed

    Liu, Shuo; Liu, An-An; Zhang, Ruidan; Ren, Zefeng

    2016-04-01

    We have designed a compact ultrahigh vacuum/high-pressure system for in situ broadband infrared (IR) sum frequency generation vibrational spectroscopy (SFG-VS) studies. In this system, we have achieved a significant reduction in the distance between the sample and the optical window (<5 mm), which in turn considerably reduces the IR absorption from the gas phase under high pressure conditions. Moreover, with this new system, the IR transmission under high pressure conditions can be measured in situ for calibrating the SFG spectra. Therefore, this modified technique can allow us to study the vibrational spectra of adsorbates on single crystals or polycrystalline foils under high pressure. The preliminary results from SFG measurements of a model CH3OH/TiO2(110) system under both ultrahigh vacuum and high pressure conditions are reported here. These results suggest that this newly developed system is potentially a powerful tool for investigating adsorbate structures and surface reactions under both ultrahigh vacuum and real conditions. PMID:27131685

  3. Cold Vacuum Drying Facility Crane and Hoist System Design Description (SYS 14)

    SciTech Connect

    TRAN, Y.S.

    2000-06-07

    This system design description (SDD) is for the Cold Vacuum Drying (CVD) Facility overhead crane and hoist system. The overhead crane and hoist system is a general service system. It is located in the process bays of the CVD Facility, supports the processes required to drain the water and dry the spent nuclear fuel (SNF) contained in the multi-canister overpacks (MCOs) after they have been removed from the K-Basins. The location of the system in the process bay is shown.

  4. Cold Vacuum Drying (CVD) Facility Safety Class Instrumentation and Control System Design Description SYS 93-2

    SciTech Connect

    WHITEHURST, R.

    1999-07-02

    This document describes the Cold Vacuum Drying Facility (CVDF) Safety Class Instrumentation and Control system (SCIC). The SCIC provides safety functions and features to protect the environment, off-site and on-site personnel and equipment. The function of the SCIC is to provide automatic trip features, valve interlocks, alarms, indication and control for the cold vacuum drying process.

  5. ACCELERATORS: Timing system of HIRFL-CSR

    NASA Astrophysics Data System (ADS)

    Dong, Jin-Mei; Yuan, You-Jin; Qiao, Wei-Min; Jing, Lan; Zhang, Wei

    2009-05-01

    The national science project HIRFL-CSR has recently been officially accepted. As a cyclotron and synchrotron complex, it puts some particularly high demands on the control system. There are hundreds of pieces of equipment that need to be synchronized. An integrated timing control system is built to meet these demands. The output rate and the accuracy of the controller are 16 bit/μs. The accuracy of the time delay reaches 40 ns. The timing control system is based on a typical event distribution system, which adopts the new event generation and the distribution scheme. The scheme of the timing control system with innovation points, the architecture and the implemented method are presented in the paper.

  6. Acceleration display system for aircraft zero-gravity research

    NASA Technical Reports Server (NTRS)

    Millis, Marc G.

    1987-01-01

    The features, design, calibration, and testing of Lewis Research Center's acceleration display system for aircraft zero-gravity research are described. Specific circuit schematics and system specifications are included as well as representative data traces from flown trajectories. Other observations learned from developing and using this system are mentioned where appropriate. The system, now a permanent part of the Lewis Learjet zero-gravity program, provides legible, concise, and necessary guidance information enabling pilots to routinely fly accurate zero-gravity trajectories. Regular use of this system resulted in improvements of the Learjet zero-gravity flight techniques, including a technique to minimize later accelerations. Lewis Gates Learjet trajectory data show that accelerations can be reliably sustained within 0.01 g for 5 consecutive seconds, within 0.02 g for 7 consecutive seconds, and within 0.04 g for up to 20 second. Lewis followed the past practices of acceleration measurement, yet focussed on the acceleration displays. Refinements based on flight experience included evolving the ranges, resolutions, and frequency responses to fit the pilot and the Learjet responses.

  7. Small Accelerators for the Next Generation of BNCT Irradiation Systems

    SciTech Connect

    Kobayashi, T.; Tanaka, K.; Bengua, G.; Hoshi, M.; Nakagawa, Y.

    2005-01-15

    The neutron irradiation system for boron neutron capture therapy (BNCT) using compact accelerators installed at hospitals was mainly investigated for the usage of direct neutrons from near-threshold {sup 7}Li(p,n){sup 7}Be, and moderated neutrons from 2.5 MeV {sup 7}Li(p,n){sup 7}Be reactions and other reactions. This kind of system can supply the medical doctors and patients with convenience to carry out BNCT in hospitals. The accelerator system would be regarded as the next-generation of BNCT in the near future.

  8. Emerging Standards with Application to Accelerator Safety System Design

    NASA Astrophysics Data System (ADS)

    Mahoney, K.; Robertson, H.

    1997-05-01

    This paper addresses international standards which can be applied to the requirements for accelerator personnel safety systems. Particular emphasis is given to standards which specify requirements for safety interlock systems which employ programmable electronic subsystems. The work draws on methodologies currently under development for the medical, process control, and aerospace industries. The paper then goes on to show how these methods may be applied to accelerator safety system design. Detailed examples are drawn from the recently approved standard ``ISA-S84'' and the draft standard ``IEC1508''.

  9. Space Suit Portable Life Support System (PLSS) 2.0 Unmanned Vacuum Environment Testing

    NASA Technical Reports Server (NTRS)

    Watts, Carly; Vogel, Matthew

    2016-01-01

    For the first time in more than 30 years, an advanced space suit Portable Life Support System (PLSS) design was operated inside a vacuum chamber representative of the flight operating environment. The test article, PLSS 2.0, was the second system-level integrated prototype of the advanced PLSS design, following the PLSS 1.0 Breadboard that was developed and tested throughout 2011. Whereas PLSS 1.0 included five technology development components with the balance the system simulated using commercial-off-the-shelf items, PLSS 2.0 featured first generation or later prototypes for all components less instrumentation, tubing and fittings. Developed throughout 2012, PLSS 2.0 was the first attempt to package the system into a flight-like representative volume. PLSS 2.0 testing included an extensive functional evaluation known as Pre-Installation Acceptance (PIA) testing, Human-in-the-Loop testing in which the PLSS 2.0 prototype was integrated via umbilicals to a manned prototype space suit for 19 two-hour simulated EVAs, and unmanned vacuum environment testing. Unmanned vacuum environment testing took place from 1/9/15-7/9/15 with PLSS 2.0 located inside a vacuum chamber. Test sequences included performance mapping of several components, carbon dioxide removal evaluations at simulated intravehicular activity (IVA) conditions, a regulator pressure schedule assessment, and culminated with 25 simulated extravehicular activities (EVAs). During the unmanned vacuum environment test series, PLSS 2.0 accumulated 378 hours of integrated testing including 291 hours of operation in a vacuum environment and 199 hours of simulated EVA time. The PLSS prototype performed nominally throughout the test series, with two notable exceptions including a pump failure and a Spacesuit Water Membrane Evaporator (SWME) leak, for which post-test failure investigations were performed. In addition to generating an extensive database of PLSS 2.0 performance data, achievements included requirements and

  10. An RFQ accelerator system for MeV ion implantation

    NASA Astrophysics Data System (ADS)

    Hirakimoto, Akira; Nakanishi, Hiroaki; Fujita, Hiroyuki; Konishi, Ikuo; Nagamachi, Shinji; Nakahara, Hiroshi; Asari, Masatoshi

    1989-02-01

    A 4-vane-type Radio-Frequency Quadrupole (RFQ) accelerator system for MeV ion implantation has been constructed and ion beams of boron and nitrogen have been accelerated successfully up to an energy of 1.01 and 1.22 MeV, respectively. The acceleration of phosphorus is now ongoing. The design was performed with two computer codes called SUPERFISH and PARMTEQ. The energy of the accelerated ions was measured by Rutherford backscattering spectroscopy. The obtained values agreed well with the designed ones. Thus we have confirmed the validity of our design and have found the possibility that the present RFQ will break through the production-use difficulty of MeV ion implantation.

  11. Preliminary description of the ground test accelerator cryogenic cooling system

    SciTech Connect

    Edeskuty, F.J.; Stewart, W.F.

    1988-01-01

    The Ground Test Accelerator (GTA) under construction at the Los Alamos National Laboratory is part of the Neutral Particle Beam Program supported by the Strategic Defense Initiative Office. The GTA is a full-sized test facility to evaluate the feasibility of using a negative ion accelerator to produce a neutral particle beam (NPB). The NPB would ultimately be used outside the earth's atmosphere as a target discriminator or as a directed energy weapon. The operation of the GTA at cryogenic temperature is advantageous for two reasons: first, the decrease of temperature caused a corresponding decrease in the rf heating of the copper in the various units of the accelerator, and second, at the lower temperature the decrease in the thermal expansion coefficient also provides greater thermal stability and consequently, better operating stability for the accelerator. This paper discusses the cryogenic cooling system needed to achieve these advantages. 5 figs., 3 tabs.

  12. COMMISSIONING OF THE SPALLATION NEUTRON SOURCE ACCELERATOR SYSTEMS

    SciTech Connect

    Plum, Michael A

    2007-01-01

    The Spallation Neutron Source accelerator complex consists of a 2.5 MeV H- front-end injector system, a 186 MeV normal-conducting linear accelerator, a 1 GeV superconducting linear accelerator, an accumulator ring, and associated beam transport lines. The linac was commissioned in five discrete runs, starting in 2002 and completed in 2005. The accumulator ring and associated beam transport lines were commissioned in two runs from January to April 2006. With the completed commissioning of the SNS accelerator, the facility has begun initial low-power operations. In the course of beam commissioning, most beam performance parameters and beam intensity goals have been achieved at low duty factor. A number of beam dynamics measurements have been performed, including emittance evolution, transverse coupling in the ring, beam instability thresholds, and beam distributions on the target. The commissioning results, achieved beam performance and initial operating experience of the SNS will be discussed

  13. A new approach to modeling linear accelerator systems

    SciTech Connect

    Gillespie, G.H.; Hill, B.W.; Jameson, R.A.

    1994-07-22

    A novel computer code is being developed to generate system level designs of radiofrequency ion accelerators with specific applications to machines of interest to Accelerator Driven Transmutation Technologies (ADTT). The goal of the Accelerator System Model (ASM) code is to create a modeling and analysis tool that is easy to use, automates many of the initial design calculations, supports trade studies used in accessing alternate designs and yet is flexible enough to incorporate new technology concepts as they emerge. Hardware engineering parameters and beam dynamics are to be modeled at comparable levels of fidelity. Existing scaling models of accelerator subsystems were used to produce a prototype of ASM (version 1.0) working within the Shell for Particle Accelerator Related Code (SPARC) graphical user interface. A small user group has been testing and evaluating the prototype for about a year. Several enhancements and improvements are now being developed. The current version of ASM is described and examples of the modeling and analysis capabilities are illustrated. The results of an example study, for an accelerator concept typical of ADTT applications, is presented and sample displays from the computer interface are shown.

  14. A new approach to modeling linear accelerator systems

    SciTech Connect

    Gillespie, George H.; Hill, Barrey W.; Jameson, Robert A.

    1995-09-15

    A novel computer code is being developed to generate system level designs of radiofrequency ion accelerators with specific applications to machines of interest to Accelerator Driven Transmutation Technologies (ADTT). The goal of the Accelerator System Model (ASM) code is to create a modeling and analysis tool that is easy to use, automates many of the initial design calculations, supports trade studies used in assessing alternate designs and yet is flexible enough to incorporate new technology concepts as they emerge. Hardware engineering parameters and beam dynamics are to be modeled at comparable levels of fidelity. Existing scaling models of accelerator subsystems were used to produce a prototype of ASM (version 1.0) working within the Shell for Particle Accelerator Related Code (SPARC) graphical user interface. A small user group has been testing and evaluating the prototype for about a year. Several enhancements and improvements are now being developed. The current version of ASM is described and examples of the modeling and analysis capabilities are illustrated. The results of an example parameter trade study, for an accelerator concept typical of ADTT applications, is presented and sample displays from the computer interface are shown.

  15. dc power system for deuteron accelerator

    SciTech Connect

    Creek, K.O.; Liska, D.J.

    1981-01-01

    The Fusion Materials Irradiation Test (FMIT) Facility dc power system provides excitation current for all linac and High-Energy Beam Transport (HEBT) quadrupole and bending magnets, excitation for horizontal and vertical beam steering, and current-bypass shunts.

  16. Vacuum system of the high energy ring of an asymmetric B-factory based on PEP

    SciTech Connect

    Barletta, W.A.; Calderon, M.O.; Wong, R. ); Jenkins, T.M. )

    1991-05-07

    The multi-ampere currents required for high luminosity operation of an asymmetric B factory leads to extremely stressing requirements on a vacuum system suitable for maintaining long beam-gas lifetimes and acceptable background levels in the detector. We present the design for a Cu alloy vacuum chamber and its associated pumping system for the 9 GeV electron storage ring of the proposed B factory based on PEP. The excellent thermal and photo-desorption properties of Cu allows handling the high proton flux in a conventional, single chamber design with distributed ion pumps. The x-ray opacity of the Cu is sufficiently high that no additional lead shielding is necessary to protect the dipoles from the intense synchrotron radiation generated by the beam. The design allows chamber commissioning in <500 hr of operation. 5 refs., 3 figs., 2 tabs.

  17. Quantum dissipation in a neutrino system propagating in vacuum and in matter

    NASA Astrophysics Data System (ADS)

    Guzzo, Marcelo M.; de Holanda, Pedro C.; Oliveira, Roberto L. N.

    2016-07-01

    Considering the neutrino state like an open quantum system, we analyze its propagation in vacuum or in matter. After defining what can be called decoherence and relaxation effects, we show that in general the probabilities in vacuum and in constant matter can be written in a similar way, which is not an obvious result for such system. From this result, we analyze the situation where neutrino evolution satisfies the adiabatic limit and use this formalism to study solar neutrinos. We show that the decoherence effect may not be bounded by the solar neutrino data and review some results in the literature, in particular the current results where solar neutrinos were used to put bounds on decoherence effects through a model-dependent approach. We conclude explaining how and why these models are not general and we reinterpret these constraints.

  18. Waveguide transition with vacuum window for multiband dynamic nuclear polarization systems

    NASA Astrophysics Data System (ADS)

    Rybalko, Oleksandr; Bowen, Sean; Zhurbenko, Vitaliy; Ardenkjær-Larsen, Jan Henrik

    2016-05-01

    A low loss waveguide transition section and oversized microwave vacuum window covering several frequency bands (94 GHz, 140 GHz, 188 GHz) is presented. The transition is compact and was optimized for multiband Dynamic Nuclear Polarization (DNP) systems in a full-wave simulator. The window is more broadband than commercially available windows, which are usually optimized for single band operation. It is demonstrated that high-density polyethylene with urethane adhesive can be used as a low loss microwave vacuum window in multiband DNP systems. The overall assembly performance and dimensions are found using full-wave simulations. The practical aspects of the window implementation in the waveguide are discussed. To verify the design and simulation results, the window is tested experimentally at the three frequencies of interest.

  19. Ultra-high vacuum compatible optical chopper system for synchrotron x-ray scanning tunneling microscopy

    NASA Astrophysics Data System (ADS)

    Chang, Hao; Cummings, Marvin; Shirato, Nozomi; Stripe, Benjamin; Rosenmann, Daniel; Preissner, Curt; Freeland, John W.; Kersell, Heath; Hla, Saw-Wai; Rose, Volker

    2016-01-01

    High-speed beam choppers are a crucial part of time-resolved x-ray studies as well as a necessary component to enable elemental contrast in synchrotron x-ray scanning tunneling microscopy (SX-STM). However, many chopper systems are not capable of operation in vacuum, which restricts their application to x-ray studies with high photon energies, where air absorption does not present a significant problem. To overcome this limitation, we present a fully ultra-high vacuum (UHV) compatible chopper system capable of operating at variable chopping frequencies up to 4 kHz. The lightweight aluminum chopper disk is coated with Ti and Au films to provide the required beam attenuation for soft and hard x-rays with photon energies up to about 12 keV. The chopper is used for lock-in detection of x-ray enhanced signals in SX-STM.

  20. Waveguide transition with vacuum window for multiband dynamic nuclear polarization systems.

    PubMed

    Rybalko, Oleksandr; Bowen, Sean; Zhurbenko, Vitaliy; Ardenkjær-Larsen, Jan Henrik

    2016-05-01

    A low loss waveguide transition section and oversized microwave vacuum window covering several frequency bands (94 GHz, 140 GHz, 188 GHz) is presented. The transition is compact and was optimized for multiband Dynamic Nuclear Polarization (DNP) systems in a full-wave simulator. The window is more broadband than commercially available windows, which are usually optimized for single band operation. It is demonstrated that high-density polyethylene with urethane adhesive can be used as a low loss microwave vacuum window in multiband DNP systems. The overall assembly performance and dimensions are found using full-wave simulations. The practical aspects of the window implementation in the waveguide are discussed. To verify the design and simulation results, the window is tested experimentally at the three frequencies of interest. PMID:27250449

  1. Emerging standards with application to accelerator safety systems

    SciTech Connect

    Mahoney, K.L.; Robertson, H.P.

    1997-08-01

    This paper addresses international standards which can be applied to the requirements for accelerator personnel safety systems. Particular emphasis is given to standards which specify requirements for safety interlock systems which employ programmable electronic subsystems. The work draws on methodologies currently under development for the medical, process control, and nuclear industries.

  2. Klystron based high power rf system for proton accelerator

    SciTech Connect

    Pande, Manjiri; Shrotriya, Sandip; Sharma, Sonal; Patel, Niranjan; Handu, Verander E-mail: manjiri08@gmail.com

    2011-07-01

    As a part of ADS program a proton accelerator (20 MeV, 30 mA) and its high power RF systems (HPRF) are being developed in BARC. This paper explains design details of this klystron based HPRF system. (author)

  3. Versatile Low Level RF System For Linear Accelerators

    SciTech Connect

    Potter, James M.

    2011-06-01

    The Low Level RF (LLRF) system is the source of all of the rf signals required for an rf linear accelerator. These signals are amplified to drive accelerator and buncher cavities. It can even provide the synchronizing signal for the rf power for a synchrotron. The use of Direct Digital Synthesis (DDS) techniques results in a versatile system that can provide multiple coherent signals at the same or different frequencies with adjustable amplitudes and phase relations. Pulsing the DDS allows rf switching with an essentially infinite on/off ratio. The LLRF system includes a versatile phase detector that allows phase-locking the rf frequency to a cavity at any phase angle over the full 360 deg. range. With the use of stepper motor driven slug tuners multiple cavity resonant frequencies can be phase locked to the rf source frequency. No external phase shifters are required and there is no feedback loop phase setup required. All that is needed is to turn the frequency feedback on. The use of Digital Signal Processing (DSP) allows amplitude and phase control over the entire rf pulse. This paper describes the basic principles of a LLRF system that has been used for both proton accelerators and electron accelerators, including multiple tank accelerators, sub-harmonic and fundamental bunchers, and synchrotrons.

  4. Development of a two axis motion simulation system for thermal/vacuum satellite testing

    NASA Technical Reports Server (NTRS)

    Henderson, David; Popovich, Bert; Demore, Louis; Elm, Joe

    1988-01-01

    A two-axis motion simulation system for thermal vacuum testing of large satellites in a space simulation chamber was developed. Satellites as large as 3000 kilograms with a 4-meter diameter and a 5-meter length can be tested. This motion simulator (MS) incorporates several unique features which result in a less complicated design with improved performance when compared to previous satellite motion simulators. The design of the simulator is discussed in detail.

  5. Surface decontamination using a teleoperated vehicle and Kelly spray/vacuum system

    SciTech Connect

    Zollinger, W.T.; Dyches, G.M.

    1990-01-01

    A commercial teleoperated wheeled vehicle was fitted with a modified commercial spray/vacuum decontamination system to allow floor and wall decontamination of an existing process room in one of the chemical separations areas at the Savannah River Site (SRS). Custom end-of-arm tooling was designed to provide sufficient compliance for routine cleaning operations. An operator console was designed to allow complete control of the vehicle base and are movements as well as viewing operations via multiple television monitors. 3 refs.

  6. Surface decontamination using a teleoperated vehicle and Kelly spray/vacuum system

    SciTech Connect

    Zollinger, W.T.; Dyches, G.M.

    1990-12-31

    A commercial teleoperated wheeled vehicle was fitted with a modified commercial spray/vacuum decontamination system to allow floor and wall decontamination of an existing process room in one of the chemical separations areas at the Savannah River Site (SRS). Custom end-of-arm tooling was designed to provide sufficient compliance for routine cleaning operations. An operator console was designed to allow complete control of the vehicle base and are movements as well as viewing operations via multiple television monitors. 3 refs.

  7. Vacuum system for room temperature X-ray lithography source (XLS)

    NASA Astrophysics Data System (ADS)

    Schuchman, J. C.

    1988-09-01

    A prototype room-temperature X-Ray Lithography Source (XLS)was proposed to be built at Brookhaven National Laboratory as part of a technology-transfer- to-American-industry program. The overall machine comprises a full energy linac, a 170 meter long transport line, and a 39 meter circumference storage ring. The scope of this paper will be limited to describing the storage ring vacuum system. (AIP)

  8. Space Launch System Accelerated Booster Development Cycle

    NASA Technical Reports Server (NTRS)

    Arockiam, Nicole; Whittecar, William; Edwards, Stephen

    2012-01-01

    With the retirement of the Space Shuttle, NASA is seeking to reinvigorate the national space program and recapture the public s interest in human space exploration by developing missions to the Moon, near-earth asteroids, Lagrange points, Mars, and beyond. The would-be successor to the Space Shuttle, NASA s Constellation Program, planned to take humans back to the Moon by 2020, but due to budgetary constraints was cancelled in 2010 in search of a more "affordable, sustainable, and realistic" concept2. Following a number of studies, the much anticipated Space Launch System (SLS) was unveiled in September of 2011. The SLS core architecture consists of a cryogenic first stage with five Space Shuttle Main Engines (SSMEs), and a cryogenic second stage using a new J-2X engine3. The baseline configuration employs two 5-segment solid rocket boosters to achieve a 70 metric ton payload capability, but a new, more capable booster system will be required to attain the goal of 130 metric tons to orbit. To this end, NASA s Marshall Space Flight Center recently released a NASA Research Announcement (NRA) entitled "Space Launch System (SLS) Advanced Booster Engineering Demonstration and/or Risk Reduction." The increased emphasis on affordability is evident in the language used in the NRA, which is focused on risk reduction "leading to an affordable Advanced Booster that meets the evolved capabilities of SLS" and "enabling competition" to "enhance SLS affordability. The purpose of the work presented in this paper is to perform an independent assessment of the elements that make up an affordable and realistic path forward for the SLS booster system, utilizing advanced design methods and technology evaluation techniques. The goal is to identify elements that will enable a more sustainable development program by exploring the trade space of heavy lift booster systems and focusing on affordability, operability, and reliability at the system and subsystem levels5. For this study

  9. Endoscopic vacuum-assisted closure system (E-VAC): case report and review of the literature.

    PubMed

    Borejsza-Wysocki, Maciej; Szmyt, Krzysztof; Bobkiewicz, Adam; Malinger, Stanisław; Świrkowicz, Józef; Hermann, Jacek; Drews, Michał; Banasiewicz, Tomasz

    2015-07-01

    Negative pressure wound therapy (NPWT) has become a standard in the treatment of chronic and difficult healing wounds. Negative pressure wound therapy is applied to the wound via a special vacuum-sealed sponge. Nowadays, the endoscopic vacuum-assisted wound closure system (E-VAC) has been proven to be an important alternative in patients with upper and lower intestinal leakage not responding to standard endoscopic and/or surgical treatment procedures. Endoscopic vacuum-assisted wound closure system provides perfect wound drainage and closure of various kinds of defect and promotes tissue granulation. Our experience has shown that E-VAC may significantly improve the morbidity and mortality rate. Moreover, E-VAC may be useful in a multidisciplinary approach - from upper gastrointestinal to rectal surgery complications. On the other hand, major limitations of the E-VAC system are the necessity of repeated endoscopic interventions and constant presence of well-trained staff. Further, large-cohort studies need to be performed to establish the applicability and effectiveness of E-VAC before routine widespread use can be recommended. PMID:26240633

  10. Endoscopic vacuum-assisted closure system (E-VAC): case report and review of the literature

    PubMed Central

    Borejsza-Wysocki, Maciej; Bobkiewicz, Adam; Malinger, Stanisław; Świrkowicz, Józef; Hermann, Jacek; Drews, Michał; Banasiewicz, Tomasz

    2015-01-01

    Negative pressure wound therapy (NPWT) has become a standard in the treatment of chronic and difficult healing wounds. Negative pressure wound therapy is applied to the wound via a special vacuum-sealed sponge. Nowadays, the endoscopic vacuum-assisted wound closure system (E-VAC) has been proven to be an important alternative in patients with upper and lower intestinal leakage not responding to standard endoscopic and/or surgical treatment procedures. Endoscopic vacuum-assisted wound closure system provides perfect wound drainage and closure of various kinds of defect and promotes tissue granulation. Our experience has shown that E-VAC may significantly improve the morbidity and mortality rate. Moreover, E-VAC may be useful in a multidisciplinary approach – from upper gastrointestinal to rectal surgery complications. On the other hand, major limitations of the E-VAC system are the necessity of repeated endoscopic interventions and constant presence of well-trained staff. Further, large-cohort studies need to be performed to establish the applicability and effectiveness of E-VAC before routine widespread use can be recommended. PMID:26240633

  11. Accelerator-Feasible N-Body Nonlinear Integrable System

    SciTech Connect

    Danilov, V.; Nagaitsev, S.

    2014-12-23

    Nonlinear N-body integrable Hamiltonian systems, where N is an arbitrary number, attract the attention of mathematical physicists for the last several decades, following the discovery of some number of these systems. This paper presents a new integrable system, which can be realized in facilities such as particle accelerators. This feature makes it more attractive than many of the previous such systems with singular or unphysical forces.

  12. Performance of the beam chamber vacuum system of K = 500 cyclotron at Variable Energy Cyclotron Centre Kolkata

    SciTech Connect

    Pal, Gautam DuttaGupta, Anjan; Chakrabarti, Alok

    2014-07-15

    The beam chamber of Variable Energy Cyclotron Centre, Kolkata's K = 500 superconducting cyclotron is pumped by liquid helium cooled cryopanel with liquid nitrogen cooled radiation shield. Performance of the vacuum system was evaluated by cooling the cryopanel assembly with liquid nitrogen and liquid helium. Direct measurement of beam chamber pressure is quite difficult because of space restrictions and the presence of high magnetic field. Pressure gauges were placed away from the beam chamber. The beam chamber pressure was evaluated using a Monte Carlo simulation software for vacuum system and compared with measurements. The details of the vacuum system, measurements, and estimation of pressure of the beam chamber are described in this paper.

  13. Development of High Power Electron Beam Measuring and Analyzing System for Microwave Vacuum Electron Devices

    NASA Astrophysics Data System (ADS)

    Ruan, C. J.; Wu, X. L.; Li, Q. S.; Li, C. S.

    The measurement and analysis of high power electron beam during its formation and transmission are the basic scientific problems and key techniques for the development of high performance microwave vacuum electron devices, which are widely used in the fields of military weapon, microwave system and scientific instruments. In this paper, the dynamic parameters measurement and analysis system being built in Institute of Electronics, Chinese Academy of Sciences (IECAS) recently are introduced. The instrument are designed to determine the cross-section, the current density, and the energy resolution of the high power electron beam during its formation and transmission process, which are available both for the electron gun and the electron optics system respectively. Then the three dimension trajectory images of the electron beam can be rebuilt and display with computer controlled data acquisition and processing system easily. Thus, much more complicated structures are considered and solved completely to achieve its detection and analysis, such as big chamber with 10-6 Pa high vacuum system, the controlled detector movement system in axis direction with distance of 600 mm inside the vacuum chamber, the electron beam energy analysis system with high resolution of 0.5%, and the electron beam cross-section and density detector using the YAG: Ce crystal and CCD imaging system et al. At present, the key parts of the instrument have been finished, the cross-section experiment of the electron beam have been performed successfully. Hereafter, the instrument will be used to measure and analyze the electron beam with the electron gun and electron optics system for the single beam and multiple beam klystron, gyrotron, sheet beam device, and traveling wave tube etc. thoroughly.

  14. Ion acceleration via ‘nonlinear vacuum heating’ by the laser pulse obliquely incident on a thin foil target

    NASA Astrophysics Data System (ADS)

    Yogo, A.; Bulanov, S. V.; Mori, M.; Ogura, K.; Esirkepov, T. Zh; Pirozhkov, A. S.; Kanasaki, M.; Sakaki, H.; Fukuda, Y.; Bolton, P. R.; Nishimura, H.; Kondo, K.

    2016-02-01

    The dependence of the energy of ions accelerated during the interaction of the laser pulse obliquely incident on the thin foil target on the laser polarisation is studied experimentally and theoretically. We found that the ion energy being maximal for the p-polarisation drastically decreases when the pulse becomes s-polarised. The experimentally found dependencies of the ion energy are explained by invoking anomalous electron heating, which results in high electrostatic potential formation at the target surface. The anomalous heating of electrons beyond the energy of quiver motion in the laser field is described within the framework of a theoretical model of a driven oscillator with a step-like nonlinearity. We have demonstrated that the electron anomalous heating can be realised in two regimes: nonlinear resonance and stochastic heating, depending on the extent of stochasticity.

  15. Versatile, low-cost, computer-controlled, sample positioning system for vacuum applications

    NASA Technical Reports Server (NTRS)

    Vargas-Aburto, Carlos; Liff, Dale R.

    1991-01-01

    A versatile, low-cost, easy to implement, microprocessor-based motorized positioning system (MPS) suitable for accurate sample manipulation in a Second Ion Mass Spectrometry (SIMS) system, and for other ultra-high vacuum (UHV) applications was designed and built at NASA LeRC. The system can be operated manually or under computer control. In the latter case, local, as well as remote operation is possible via the IEEE-488 bus. The position of the sample can be controlled in three linear orthogonal and one angular coordinates.

  16. Contamination due to memory effects in filtered vacuum arc plasma deposition systems

    SciTech Connect

    Martins, D.R.; Salvadori, M.C.; Verdonck, P.; Brown, I.G.

    2002-08-13

    Thin film synthesis by filtered vacuum arc plasma deposition is a widely used technique with a number of important emerging technological applications. A characteristic feature of the method is that during the deposition process not only is the substrate coated by the plasma, but the plasma gun itself and the magnetic field coil and/or vacuum vessel section constituting the macroparticle filter are also coated to some extent. If then the plasma gun cathode is changed to a new element, there can be a contamination of the subsequent film deposition by sputtering from various parts of the system of the previous coating species. We have experimentally explored this effect and compared our results with theoretical estimates of sputtering from the SRIM (Stopping and Range of Ions in Matter) code. We find film contamination of order 10-4 - 10-3, and the memory of the prior history of the deposition hardware can be relatively long-lasting.

  17. Note: Fixture for characterizing electrochemical devices in-operando in traditional vacuum systems

    SciTech Connect

    Whaley, Josh A.; McDaniel, Anthony H.; El Gabaly, Farid; Farrow, Roger L.; Linne, Mark A.; McCarty, Kevin F.; Grass, Michael E.; Hussain, Zahid; Liu Zhi; Bluhm, Hendrik

    2010-08-15

    We describe a fixture that allows electrochemical devices to be studied under electrical bias in the type of vacuum systems commonly used in surface science. Three spring-loaded probes provide independent contacts for device operation and the characterization in vacuum or under in situ conditions with reactive gases. We document the robustness of the electrical contacts over large temperature changes and their reliability for conventional electrochemical measurements such as impedance spectroscopy. The optical access provided to the device enables the analysis by many techniques, as we demonstrate using x-ray photoelectron spectroscopy to measure local electrical potentials on a solid-oxide electrolyte device operating at high temperature in near-ambient pressure.

  18. Ultra-high speed vacuum pump system with first stage turbofan and second stage turbomolecular pump

    DOEpatents

    Jostlein, Hans

    2006-04-04

    An ultra-high speed vacuum pump evacuation system includes a first stage ultra-high speed turbofan and a second stage conventional turbomolecular pump. The turbofan is either connected in series to a chamber to be evacuated, or is optionally disposed entirely within the chamber. The turbofan employs large diameter rotor blades operating at high linear blade velocity to impart an ultra-high pumping speed to a fluid. The second stage turbomolecular pump is fluidly connected downstream from the first stage turbofan. In operation, the first stage turbofan operates in a pre-existing vacuum, with the fluid asserting only small axial forces upon the rotor blades. The turbofan imparts a velocity to fluid particles towards an outlet at a high volume rate, but moderate compression ratio. The second stage conventional turbomolecular pump then compresses the fluid to pressures for evacuation by a roughing pump.

  19. Histologic validation of vacuum sealed, formalin-free tissue preservation, and transport system.

    PubMed

    Zarbo, Richard J

    2015-01-01

    We describe five validation trials of new vacuum sealing technologies that change the approach to the preanalytic "front end" of specimen transport, handling, and processing and illustrate their adaptation and integration into existing Lean laboratory operations with reduction in formalin use and personnel exposure to this toxic and potentially carcinogenic fixative. These trials provide histologic assessment by numerous pathologists of tissues processed in this new paradigm and define the financial advantages of applying this technology to the postanalytic or "back end" process of tissue storage. We conclude that the TisssueSAFE and SealSAFE vacuum sealing systems are both promising technologies for preserving fresh human specimens that can promote a safer environment by markedly reducing formalin use in operating room theaters and can minimize formalin use by laboratories. PMID:25636425

  20. Synthesis of the System Modeling and Signal Detecting Circuit of a Novel Vacuum Microelectronic Accelerometer

    PubMed Central

    Li, Dongling; Wen, Zhiyu; Wen, Zhongquan; He, Xuefeng; Yang, Yinchuan; Shang, Zhengguo

    2009-01-01

    A novel high-precision vacuum microelectronic accelerometer has been successfully fabricated and tested in our laboratory. This accelerometer has unique advantages of high sensitivity, fast response, and anti-radiation stability. It is a prototype intended for navigation applications and is required to feature micro-g resolution. This paper briefly describes the structure and working principle of our vacuum microelectronic accelerometer, and the mathematical model is also established. The performances of the accelerometer system are discussed after Matlab modeling. The results show that, the dynamic response of the accelerometer system is significantly improved by choosing appropriate parameters of signal detecting circuit, and the signal detecting circuit is designed. In order to attain good linearity and performance, the closed-loop control mode is adopted. Weak current detection technology is studied, and integral T-style feedback network is used in I/V conversion, which will eliminate high-frequency noise at the front of the circuit. According to the modeling parameters, the low-pass filter is designed. This circuit is simple, reliable, and has high precision. Experiments are done and the results show that the vacuum microelectronic accelerometer exhibits good linearity over -1 g to +1 g, an output sensitivity of 543 mV/g, and a nonlinearity of 0.94 %. PMID:22408515

  1. Vacuum system design of the SRRC 1. 3 GeV Synchrotron radiation source

    SciTech Connect

    Chen, J.R.; Hsiung, G.Y.; Chen, D.C.; Wang, D.J.; Chen, G.S.; Liu, Y.C.

    1988-09-30

    The vacuum system design for the SRRC 1.3 GeV synchrotron light source is described. The design goal of the vacuum system is to achieve a 10 h beam life time at 200 mA beam current. Aluminum alloys are chosen as the vacuum chamber materials. Machining and extrusion methods will be applied to the fabrication of bending magnet chambers and straight chambers respectively. In order to locate pumps effectively, a computer program was written to calculate the pressure distribution around the storage ring. In the ring, the major pumps will be ion pumps and titanium sublimation pumps. Turbomolecular pumps will be used for evacuation during roughing and baking processes. At the downstream side of the bending magnet chamber, where the photon-induced desorption is ''concentrated'', a pumping port is designed to reduce the average pressure effectively; this design results in a triangular-shaped bending magnet chamber. Also, a distributed ion pumps is built in the bending magnet chamber to pump out scattered gas molecules in this region.

  2. Qualification of Target Chamber Vacuum Systems Cleanliness using Sol-Gel Coatings

    SciTech Connect

    Miller, P; Stowers, I F; Ertel, J R

    2006-01-03

    This document defines the procedure necessary to qualify the airborne molecular cleanliness (AMC) of vacuum systems (enclosures or large components) that are placed within the National Ignition Facility (NIF) target chamber or are attached to it and communicate with it during vacuum operation. This test is specific to the NIF target chamber because the allowable time dependent rate of rise in the pore filling of a sol-gel coated SAW sensor is based on some nominal change-out time for the disposable debris shields. These debris shields will be sol-gel coated and thus they represent a means of ''pumping'' AMCs from the target chamber. The debris shield pumping rate sets the allowable change in pore filling with time specified in the test procedure. This document describes a two-part procedure that provides both a static measurement of sol-gel pore filling at the end of a 48-hour test period and a dynamic record of pore-filling measured throughout the test period. Successful qualification of a vacuum system requires that both the static and dynamic measurements meet the criteria set forth in Section 7 of this document.

  3. Design of a ram accelerator mass launch system

    NASA Technical Reports Server (NTRS)

    Aarnio, Michael; Armerding, Calvin; Berschauer, Andrew; Christofferson, Erik; Clement, Paul; Gohd, Robin; Neely, Bret; Reed, David; Rodriguez, Carlos; Swanstrom, Fredrick

    1988-01-01

    The ram accelerator mass launch system has been proposed to greatly reduce the costs of placing acceleration-insensitive payloads into low earth orbit. The ram accelerator is a chemically propelled, impulsive mass launch system capable of efficiently accelerating relatively large masses from velocities of 0.7 km/sec to 10 km/sec. The principles of propulsion are based on those of a conventional supersonic air-breathing ramjet; however the device operates in a somewhat different manner. The payload carrying vehicle resembles the center-body of the ramjet and accelerates through a stationary tube which acts as the outer cowling. The tube is filled with premixed gaseous fuel and oxidizer mixtures that burn in the vicinity of the vehicle's base, producing a thrust which accelerates the vehicle through the tube. This study examines the requirement for placing a 2000 kg vehicle into a 500 km circular orbit with a minimum amount of on-board rocket propellant for orbital maneuvers. The goal is to achieve a 50 pct payload mass fraction. The proposed design requirements have several self-imposed constraints that define the vehicle and tube configurations. Structural considerations on the vehicle and tube wall dictate an upper acceleration limit of 1000 g's and a tube inside diameter of 1.0 m. In-tube propulsive requirements and vehicle structural constraints result in a vehicle diameter of 0.76 m, a total length of 7.5 m and a nose-cone half angle of 7 degrees. An ablating nose-cone constructed from carbon-carbon composite serves as the thermal protection mechanism for atmospheric transit.

  4. Cold Vacuum Drying facility personnel monitoring system design description (SYS 12)

    SciTech Connect

    PITKOFF, C.C.

    1999-07-06

    This document describes the Cold Vacuum Drying Facility (CVDF) instrument air (IA) system that provides instrument quality air to the CVDF. The IA system provides the instrument quality air used in the process, HVAC, and HVAC instruments. The IA system provides the process skids with air to aid in the purging of the annulus of the transport cask. The IA system provides air for the solenoid-operated valves and damper position controls for isolation, volume, and backdraft in the HVAC system. The IA system provides air for monitoring and control of the HVAC system, process instruments, gas-operated valves, and solenoid-operated instruments. The IA system also delivers air for operating hand tools in each of the process bays.

  5. Description of an innovative vacuum pumping and energy absorption system for a multi-megawatt electric propulsion test facility

    SciTech Connect

    Coomes, E.P.; Bennett, D.W.; Lundgren, R.A.; McClanahan, E.D.; Moss, R.W.

    1988-03-01

    The development of high power magnetoplasmadynamic (MPD) thrusters is rapidly approaching an impasse to further development: the lack of a facility with adequate vacuum pumping and energy removal capacity to support the resolution of key MPD life and performance issues by FY-93. Several studies have been performed that identify vacuum systems or facility concepts that would alleviate this problem. Although feasible, the proposed vacuum systems require significant research and development; and the proposed facility concepts all require the added development of a gas dynamic diffuser. 8 refs., 4 figs.

  6. Vacuum-Based Time-Resolved Photoluminescence Measurement System Provides New Capability (Fact Sheet)

    SciTech Connect

    Not Available

    2011-11-01

    New measurement capability measures semiconductor minority-carrier lifetimes in conditions that simulate thin-film photovoltaic manufacturing environments. National Renewable Energy Laboratory (NREL) scientists have developed a new capability for measuring time-resolved photoluminescence (TRPL) in controlled environments, including under high vacuum and at elevated temperatures. This system enables the simulation of conditions in a thin-film photovoltaic (PV) manufacturing line. NREL's work in recent years has demonstrated a clear correlation between minority-carrier lifetime and thin-film PV device performance. Hence, the thin-film PV industry-both CIGS and CdTe-has a high level of interest for in-line metrology using NREL's TRPL system. The system, shown below, couples femtosecond laser pulses with optical fibers while avoiding spectral or temporal broadening over a wide range of wavelengths. The optics are designed to collect and couple the TRPL signal into the same fiber used to deliver the laser pulses. The capability is coupled into a high-vacuum chamber that can heat samples to 500 C or higher and expose them to reactive ambients. This tool will allow NREL to partner with industry to evaluate TRPL as a diagnostic at multiple stages of the manufacturing process and determine correlations to final module efficiency. The TRPL system has the potential to significantly improve manufacturing yield and throughput of current thin-film PV manufacturers. NREL developed a time-resolved photoluminescence (TRPL) system that can operate under high vacuum and at high temperatures. Thin-film PV performance can be better assessed because of its clear correlation with minority-carrier lifetime, which can be measured by NREL's TRPL system. Photovoltaic thin-film makers will be able to measure in-line TRPL at various stages of the manufacturing process, potentially leading to improved yield and throughput.

  7. SYSTEMS TO ACCELERATE IN SITU STABILIZATION OF WASTE DEPOSITS

    EPA Science Inventory

    In-situ systems to accelerate the stabilization of waste deposits involve three essential elements: selection of a chemical or biological agent (reactant) which can react with and stabilize the waste, a method for delivery of the reactant to the deposit and a method for recovery ...

  8. Cryogenic cooling system for the ground test accelerator

    SciTech Connect

    Edeskuty, F.J.; Stewart, W.F.; Moeller, J.; Durham, F.; Spulgis, I.

    1993-06-01

    A cryogenic cooling system has been designed, built and tested for the Ground Test Accelerator (GTA) at the Los Alamos National Laboratory. Major components of the GTA require cooling to less than 50 K to reduce rf-heating and to increase thermal stability. The cooling system is capable of cooling (at an acceptable rate for thermal stresses) the cryogenically cooled components and then maintaining them at their operating temperature during accelerator testing for all modes and power levels of operation. The accelerator components are cooled by circulating cold, dense helium gas (about 21 K and 2.1 MPa) through the components. The circulating helium is refrigerated in a heat exchanger that uses boiling liquid hydrogen as a source of refrigeration. The cryogenic cooling system consists of the following major components: a liquid hydrogen (LH{sub 2}) storage Dewar with a transfer line to an LH{sub 2} run tank containing an LH{sub 2}/gaseous helium (GHe) heat exchanger, circulation lines, and a circulation pump. The system, sized to cool a load of approximately 40 kW at temperatures as low as 20 K, is operational, but has not yet been operated in conjunction with the accelerator.

  9. Cryogenic cooling system for the ground test accelerator

    SciTech Connect

    Edeskuty, F.J.; Stewart, W.F.; Moeller, J.; Durham, F. ); Spulgis, I. )

    1993-01-01

    A cryogenic cooling system has been designed, built and tested for the Ground Test Accelerator (GTA) at the Los Alamos National Laboratory. Major components of the GTA require cooling to less than 50 K to reduce rf-heating and to increase thermal stability. The cooling system is capable of cooling (at an acceptable rate for thermal stresses) the cryogenically cooled components and then maintaining them at their operating temperature during accelerator testing for all modes and power levels of operation. The accelerator components are cooled by circulating cold, dense helium gas (about 21 K and 2.1 MPa) through the components. The circulating helium is refrigerated in a heat exchanger that uses boiling liquid hydrogen as a source of refrigeration. The cryogenic cooling system consists of the following major components: a liquid hydrogen (LH[sub 2]) storage Dewar with a transfer line to an LH[sub 2] run tank containing an LH[sub 2]/gaseous helium (GHe) heat exchanger, circulation lines, and a circulation pump. The system, sized to cool a load of approximately 40 kW at temperatures as low as 20 K, is operational, but has not yet been operated in conjunction with the accelerator.

  10. Cryogenic cooling system for the Ground Test Accelerator

    SciTech Connect

    Edeskuty, F.J.; Stewart, W.F.; Moeller, J.; Durham, F.; Spulgis, I.

    1994-12-31

    A cryogenic cooling system has been designed, built and tested for the Ground Test Accelerator (GTA) at the Los Alamos National Laboratory. Major components of the GTA require cooling to less than 50 K to reduce rf-heating and to increase thermal stability. The cooling system is capable of cooling (at an acceptable rate for thermal stresses) the cryogenically cooled components and then maintaining them at their operating temperature during accelerator testing for all modes and power levels of operation. The accelerator components are cooled by circulating cold, dense helium gas (about 21 K and 2.1 MPa) through the components. The circulating helium is refrigerated in a heat exchanger that uses boiling liquid hydrogen as a source of refrigeration. The cryogenic cooling system consists of the following major components: a liquid hydrogen (LH{sub 2}) storage Dewar with a transfer line to an LH{sub 2} run tank containing an LH{sub 2}/gaseous helium (GHe) heat exchanger, circulation lines, and a circulation pump. The system, sized to cool a load of approximately 40 kW at temperatures as low as 20 K, is operational, but has not yet been operated in conjunction with the accelerator.

  11. Sealing system for a movable vacuum chamber of a charged particle beam machine

    SciTech Connect

    Anderl, P.; Kappelsberger, E.; Konig, D.; Monch, C.; Scheffels, W.; Steigerwald, K.

    1982-11-09

    A system for sealing the working vacuum chamber of a charged particle beam machine which is movable with respect to a workpiece is disclosed. The system includes a housing with a central compartment having wire-shaped elements urged against the workpiece to provide a seal therebetween, and lateral compartments, each having a packing of sealing material which is biased against the workpiece surface of a spring arrangement. Rollers and a flexible lip seal arrangement having a flexible sheath of synthetic rubber are also disclosed.

  12. Vacuum Rabi splitting effect in nanomechanical QED system with nonlinear resonator

    NASA Astrophysics Data System (ADS)

    Zhao, MingYue; Gao, YiBo

    2016-08-01

    Considering the intrinsic nonlinearity in a nanomechanical resonator coupled to a charge qubit, vacuum Rabi splitting effect is studied in a nanomechanical QED (qubit-resonator) system. A driven nonlinear Jaynes-Cummings model describes the dynamics of this qubit-resonator system. Using quantum regression theorem and master equation approach, we have calculated the two-time correlation spectrum analytically. In the weak driving limit, these analytical results clarify the influence of the driving strength and nonlinearity parameter on the correlation spectrum. Also, numerical calculations confirm these analytical results.

  13. Leak testing of cryogenically pumped large-volume high-vacuum systems

    NASA Astrophysics Data System (ADS)

    Sherlock, Charles N.

    1988-01-01

    The problems that may occur in the cryogenically pumped large-volume high-vacuum chambers (LVHVCs), used for the environmental testing of aerospace components and systems, are examined. Consideration is given to the designs of the LVHVCs and the cryogenic pumps. In the procedure of leak testing with tracer gas, the success of testing depends on attaining the required test sensitivity with speed, economy, and reliability. The steps required to speed up the leak location phase of the leak testing procedure and to thoroughly clean every penetration (i.e., fitting or nozzle) of the system are discussed.

  14. TRIDAQ systems in HEP experiments at LHC accelerator

    NASA Astrophysics Data System (ADS)

    Zagozdzińska, Agnieszka; Romaniuk, Ryszard S.; Poźniak, Krzysztof T.; Zalewski, Piotr

    2013-01-01

    The paper describes Trigger and Data Acquisition (TRIDAQ) systems of accelerator experiments for High Energy Physics. The background for physics research comprises assumptions of the Standard Model theory with basic extensions. On this basis, a structure of particle detector system is described, with emphasis on the following functional blocks: Front-End Electronics, Trigger and DAQ systems. The described solutions are used in the LHC experiments: ATLAS, ALICE, CMS and LHCb. They are also used in other accelerator experiments. Data storage and processing functionality is divided into two hardware systems: Trigger and Data Acquisition, that are dependent on each other. High input data rate impose relevant choices for the architecture and parameters of both systems. The key parameters include detailed system structure and its overall latency. Trigger structure is defined by the physics requirements and the storage capability of DAQ system. Both systems are designed to achieve the highest possible space and time resolution for particle detection. Trigger references are reviewed [1-43] as well as chosen accelerator research efforts origination in this country [44-83].

  15. Nuclear data needs for accelerator-driven transmutation systems

    SciTech Connect

    Arthur, E.D.; Wilson, W.B.; Young, P.G.

    1994-07-01

    The possibilities of several new technologies based on use of intense, medium-energy proton accelerators are being investigated at Los Alamos National Laboratory. The potential new areas include destruction of long-lived components of nuclear waste, plutonium burning, energy production, and production of tritium. The design, assessment, and safety analysis of potential facilities involves the understanding of complex combinations of nuclear processes, which in turn places new requirements on nuclear data that transcend the traditional needs of the fission and fusion reactor communities. In this paper an assessment of the nuclear data needs for systems currently being considered in the Los Alamos Accelerator-Driven Transmutation Technologies program is given.

  16. The high altitude qualification tests of the cryogenic and vacuum system for ALMA

    NASA Astrophysics Data System (ADS)

    Silber, Armin

    2012-09-01

    The Cryogenic System of ALMA is one of the core sub systems of the Front End low noise receiver and the failsafe operation is mandatory to ensure the successful astronomical observations. ESO has done a comprehensive test campaign on the ALMA operational site Chajnantor1 at an altitude of 5000m, to qualify this system for the harsh operational conditions. In this contribution we will present an overview of those Qualification tests which have been carried out on ALMA`s 4K Cryogenic and Vacuum System components and the additional required measures to operate the system under the special environmental conditions, respectively the operational constrains. That will include the findings concerning the optimization of the remote diagnostic and the definition of additional monitor and control parameters. The resulting solutions have considerable influence on the maintenance processes, the operational staff requirements and the reduction of the operational costs in particularly with regards to the large system number of 66 antennas.

  17. Vacuum pump aids ejectors

    SciTech Connect

    Nelson, R.E.

    1982-12-01

    The steam ejector/vacuum pump hybrid system has been operating satisfactorily since the summer of 1981. This system has essentially been as troublefree as the all-ejector system and, of course, has provided a substantial cost savings. Construction is currently under way to convert the vacuum system of another crude still which is equipped with steam ejectors and barometric condensers to the hybrid system of steam ejectors, surface condensers, and vacuum pumps. This current project is even more financially attractive because it allows a dirty water cooling tower which serves the barometric condensers to be shut down. Providing a vacuum for crude distillation vacuum towers with this hybrid system is by no means the only application of this technique. Any vacuum system consisting of all steam ejectors would be a candidate for this hybrid system and the resulting savings in energy.

  18. ENHANCED THERMAL VACUUM TEST CAPABILITY FOR RADIOISOTOPE POWER SYSTEMS AT THE IDAHO NATIONAL LABORATORY BETTER SIMULATES ENVIRONMENTAL CONDITIONS OF SPACE

    SciTech Connect

    J. C. Giglio; A. A. Jackson

    2012-03-01

    The Idaho National Laboratory (INL) is preparing to fuel and test the Advanced Stirling Radioisotope Generator (ASRG), the next generation space power generator. The INL identified the thermal vacuum test chamber used to test past generators as inadequate. A second vacuum chamber was upgraded with a thermal shroud to process the unique needs and to test the full power capability of the new generator. The thermal vacuum test chamber is the first of its kind capable of testing a fueled power system to temperature that accurately simulate space. This paper outlines the new test and set up capabilities at the INL.

  19. Development of a two-color projection system for the KHILS Vacuum Cold Chamber (KVACC)

    NASA Astrophysics Data System (ADS)

    Flynn, David S.; Marlow, Steven A.; Kircher, James R.; Glattke, Eric W.; Murrer, Robert Lee; Weir, John S.

    2000-07-01

    The KHILS Vacuum Cold Chamber (KVACC) was developed to provide the capability of performing hardware-in-the-loop testing of infrared seekers requiring scenes involving cold backgrounds. Being able to project cold backgrounds enables the projector to simulate high-altitude exoatmospheric engagements. Previous tests with the KVACC projection system have used only one resistive-array projection device. In order to realistically stimulate a 2-color seeker, it is necessary to project in two, independently controlled IR bands. Missile interceptors commonly use two or more colors; thus, a 2-color projection capability has been developed for the KVACC system. The 2- color projection capability is being accomplished by optically combining two Phase 3 WISP arrays with a dichroic beam combiner. Both WISP arrays are cooled to user-selected temperatures ranging from ambient temperature to below 150 K. In order to test the projection system, a special-purpose camera has also been developed. The camera is designed to operate inside the vacuum chamber. It has a cooled, all- reflective broadband optical system to enable the measurement of low radiance levels in the 3 - 12 micrometer spectrum. Camera upgrades later this year will allow measurements in two independent wavebands. Both the camera and the projector will be described in this paper.

  20. Advantages and safety features using foundation fieldbus-H1 based instrumentation & control for cryo system in accelerators

    NASA Astrophysics Data System (ADS)

    Kaushik, S.; Haneef, K. K. M.; Jayaram, M. N.; Lalsare, D. K.

    2008-05-01

    Large accelerator programme instrumentation and control for monitoring of large no. of parameters for cryogenic/cooling system. The parameters are Cryo Temperature, Vacuum, He Level and He flow etc. The circumference of the accelerator may vary up to several kilometers. Large size accelerators require huge cabling and hardware. The use of foundation fieldbus based Transmitters for measurement and Control valves field positioners for cryo system shall reduce the cabling, hardware, maintenance and enhance data processing and interoperability. Safety is an important requirement for efficient, trouble free and safe operation of any process industry such as cryo used in accelerators. Instrumentation and Control systems can be developed using Foundation Field Bus. The safety features in foundation field bus system can be achieved by use of intrinsic safe devices, fail safe configuration, minimize the hazard by distribution of control function blocks, short circuit preventers. Apart from above features, the significant cable reduction in the fieldbus system reduces the hazard due to electrical cable fire, which is considered one of the major risk in industry. Further the reliability in fieldbus can be improved by hot stand-by redundant power supply, hot stand-by redundant CPU, hot stand-by redundant network capability and use of link active scheduler.

  1. Molecular branching ratio method for intensity calibration of optical systems in the vacuum ultraviolet

    NASA Technical Reports Server (NTRS)

    Mumma, M. J.

    1972-01-01

    A state-of-the-art review is given of the molecular branching ratio method for intensity calibration in the vacuum ultraviolet. Ways are described for determining both relative and quantitative responses in the wavelength range 1000 A to 3000 A. The molecular band systems which are discussed are the following: H2(B 1 Sigma u +)-(X 1 Sigma g +), H2(C 1 Pi u)-(X 1 Sigma g +), N2(A 1 Pi g)-(X 1 Sigma g +), CO(A 1 Pi)-(X 1 Sigma +), NO(A 2 Sigma +)-(X 2 Pi r), and NO(+) (A 1 Pi)-(X 1 Sigma +).

  2. O-ring sealing arrangements for ultra-high vacuum systems

    SciTech Connect

    Flaherty, R.; Kim, C.

    1981-08-04

    An all metal reusable o-ring sealing arrangement is disclosed for sealing two concentric tubes in an ultra-high vacuum system. An o-ring of a heat recoverable alloy such as nitinol is concentrically positioned between protruding sealing rings of the concentric tubes. The o-ring is installed between the tubes while in a stressed martensitic state and is made to undergo a thermally induced transformation to an austenitic state. During the transformation the o-ring expands outwardly and contracts inwardly toward a previously sized austenitic configuration, thereby sealing against the protruding sealing rings of the concentric tubes.

  3. Influence of the electrode system on the emission characteristics of a vacuum spark

    SciTech Connect

    Bashutin, O. A. Alkhimova, M. A.; Vovchenko, E. D.; Dodulad, E. I.; Savelov, A. S.; Sarantsev, S. A.

    2013-11-15

    The influence of the electrode system on the emission characteristics of a high-current low-inductance vacuum spark is investigated. It is shown that the structure and composition of the spark plasma radiating in the X-ray spectral range depend substantially on the geometry and relative position of the electrodes. A mechanism related to the effect of the initial distribution of the electric field in the electrode gap is proposed to explain such a dependence. The conditions in which the radiating plasma forms from the erosion products of one or both electrodes are determined.

  4. O-Ring sealing arrangements for ultra-high vacuum systems

    DOEpatents

    Kim, Chang-Kyo; Flaherty, Robert

    1981-01-01

    An all metal reusable O-ring sealing arrangement for sealing two concentric tubes in an ultra-high vacuum system. An O-ring of a heat recoverable alloy such as Nitinol is concentrically positioned between protruding sealing rings of the concentric tubes. The O-ring is installed between the tubes while in a stressed martensitic state and is made to undergo a thermally induced transformation to an austenitic state. During the transformation the O-ring expands outwardly and contracts inwardly toward a previously sized austenitic configuration, thereby sealing against the protruding sealing rings of the concentric tubes.

  5. The Awful Truth About Zero-Gravity: Space Acceleration Measurement System; Orbital Acceleration Research Experiment

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Earth's gravity holds the Shuttle in orbit, as it does satellites and the Moon. The apparent weightlessness experienced by astronauts and experiments on the Shuttle is a balancing act, the result of free-fall, or continuously falling around Earth. An easy way to visualize what is happening is with a thought experiment that Sir Isaac Newton did in 1686. Newton envisioned a mountain extending above Earth's atmosphere so that friction with the air would be eliminated. He imagined a cannon atop the mountain and aimed parallel to the ground. Firing the cannon propels the cannonball forward. At the same time, Earth's gravity pulls the cannonball down to the surface and eventual impact. Newton visualized using enough powder to just balance gravity so the cannonball would circle the Earth. Like the cannonball, objects orbiting Earth are in continuous free-fall, and it appears that gravity has been eliminated. Yet, that appearance is deceiving. Activities aboard the Shuttle generate a range of accelerations that have effects similar to those of gravity. The crew works and exercises. The main data relay antenna quivers 17 times per second to prevent 'stiction,' where parts stick then release with a jerk. Cooling pumps, air fans, and other systems add vibration. And traces of Earth's atmosphere, even 200 miles up, drag on the Shuttle. While imperceptible to us, these vibrations can have a profound impact on the commercial research and scientific experiments aboard the Shuttle. Measuring these forces is necessary so that researchers and scientists can see what may have affected their experiments when analyzing data. On STS-107 this service is provided by the Space Acceleration Measurement System for Free Flyers (SAMS-FF) and the Orbital Acceleration Research Experiment (OARE). Precision data from these two instruments will help scientists analyze data from their experiments and eliminate outside influences from the phenomena they are studying during the mission.

  6. The Master Equation for Two-Level Accelerated Systems at Finite Temperature

    NASA Astrophysics Data System (ADS)

    Tomazelli, J. L.; Cunha, R. O.

    2016-07-01

    In this work, we study the behaviour of two weakly coupled quantum systems, described by a separable density operator; one of them is a single oscillator, representing a microscopic system, while the other is a set of oscillators which perform the role of a reservoir in thermal equilibrium. From the Liouville-Von Neumann equation for the reduced density operator, we devise the master equation that governs the evolution of the microscopic system, incorporating the effects of temperature via Thermofield Dynamics formalism by suitably redefining the vacuum of the macroscopic system. As applications, we initially investigate the behaviour of a Fermi oscillator in the presence of a heat bath consisting of a set of Fermi oscillators and that of an atomic two-level system interacting with a scalar radiation field, considered as a reservoir, by constructing the corresponding master equation which governs the time evolution of both sub-systems at finite temperature. Finally, we calculate the energy variation rates for the atom and the field, as well as the atomic population levels, both in the inertial case and at constant proper acceleration, considering the two-level system as a prototype of an Unruh detector, for admissible couplings of the radiation field.

  7. Material Total Mass Loss in Vacuum Obtained From Various Outgassing Systems

    NASA Technical Reports Server (NTRS)

    Scialdone, John; Isaac, Peggy; Clatterbuck, Carroll; Hunkeler, Ronald

    2000-01-01

    Several instruments including the Cahn Microbalance, the Knudsen Cell, the micro-CVCM, and the vacuum Thermogravimetric Analyzer (TGA) were used in the testing of a graphite/epoxy (GR/EP) composite that is proposed for use as a rigidizing element of an inflatable deployment system. This GR/EP will be cured in situ. The purpose of this testing is to estimate the gaseous production resulting from the curing of the GR/EP composite, to predict the resulting pressure, and to calculate the required venting. Every test was conducted under vacuum at 125 degrees C for 24 hours. Upon comparison of the results, the ASTM E-595 was noted to have given readings that were consistently lower than those obtained using the other instruments, which otherwise provided similar results. The GR/EP was tested using several different geometric arrangements. This paper describes the analysis evaluating the molecular and continuum flow of the outgassing products issuing from the exit port of the ASTM E-595 system. The effective flow conductance provided by the physical dimensions of the vent passage of the ASTM E-595 system and that of the material sample among other factors were investigated to explain the reduced amount of outgassing released during the 24-hour test period.

  8. Outgassing Total Mass Loss Obtained with Micro-CVCM and Other Vacuum Systems

    NASA Technical Reports Server (NTRS)

    Scialdone, John; Isaac, Peggy; Clatterbuck, Carroll; Hunkeler, Ronald; Powers, Edward I. (Technical Monitor)

    2000-01-01

    Several instruments including the Cahn Microbalance, the Knudsen Cell, the micro-CVCM, and the vacuum Thermogravimetric Analyzer (TGA) were used in the testing of a graphite epoxy (GR/EP) composite that is proposed for use as a rigidizing element of an inflatable deployment system. This GR/EP will be cured in situ. The purpose of this testing is to estimate the gaseous production resulting from the curing of the GR/EP composite, to predict the resulting pressure, and to calculate the required venting. Every test was conducted under vacuum at 125 C for 24 hours. Upon comparison of the results, the ASTM E-595 was noted to have given readings that were consistently lower than those obtained using the other instruments, which otherwise provided similar results. The GR/EP was tested using several different geometric arrangements. This paper describes the analysis evaluating the molecular and continuum flow of the outgassing products issuing from the exit port of the ASTM E-595 system. The effective flow conductance provided by the physical dimensions of the vent passage of the ASTM E-595 system and that of the material sample among other factors were investigated to explain the reduced amount of outgassing released during the 24-hour test period,

  9. Outgassing Total Mass Loss Obtained with Micro-CVCM and other Vacuum Systems

    NASA Technical Reports Server (NTRS)

    Scialdone, John J.; Isaac, Peggy A.; Clatterbuck, Carroll H.; Hunkeler, Ronald E.; Powers, Edward I. (Technical Monitor)

    2000-01-01

    Several instruments including the Cahn Microbalance the Knudsen Cell, the micro-CVCM, and the vacuum Thermogravimetric Analyzer (TGA) were used in the testing of a graphite epoxy (GR/EP) composite that is proposed for use as a rigidizing element of an inflatable deployment system. This GR/EP will be cured in situ. The purpose of this testing is to estimate the gaseous production resulting from the curing of the GR/EP composite, to predict the resulting pressure, and to calculate the required venting. Every test was conducted under vacuum at 125 C for 24 hours. Upon comparison of the results, the ASTM E-595 was noted to have given readings that were consistently lower than those obtained using the other instruments, which otherwise provided similar results. The GR/EP was tested using several different geometric arrangements. This paper describes the analysis evaluating the molecular and continuum flow of the outgassing products issuing from the exit port of the ASTM E-595 system. The effective flow conductance provided by the physical dimensions of the vent passage of the ASTM E-595 system and that of the material sample among other factors were investigated to explain the reduced amount of outgassing released during the 24-hour test period

  10. Geoscience Laser Altimeter System (GLAS) Instrument: Flight Loop Heat Pipe (LHP) Acceptance Thermal Vacuum Test

    NASA Technical Reports Server (NTRS)

    Baker, Charles; Butler, Dan; Ku, Jentung; Grob, Eric; Swanson, Ted; Nikitkin, Michael; Powers, Edward I. (Technical Monitor)

    2001-01-01

    Two loop heat pipes (LHPs) are to be used for tight thermal control of the Geoscience Laser Altimeter System (GLAS) instrument, planned for flight in late 2001. The LHPs are charged with Propylene as a working fluid. One LHP will be used to transport 110 W from a laser to a radiator, the other will transport 160 W from electronic boxes to a separate radiator. The application includes a large amount of thermal mass in each LHP system and low initial startup powers. The initial design had some non-ideal flight design compromises, resulted in a less than ideal charge level for this design concept with a symmetrical secondary wick. This less than ideal charge was identified as the source of inadequate performance of the flight LHPs during the flight thermal vacuum test in October of 2000. We modified the compensation chamber design, re-built and charged the LHPs for a final LHP acceptance thermal vacuum test. This test performed March of 2001 was 100% successful. This is the last testing to be performed on the LHPs prior to instrument thermal vacuum test. This sensitivity to charge level was shown through varying the charge on a Development Model Loop Heat Pipe (DM LHP) and evaluating performance at various fill levels. At lower fills similar to the original charge in the flight units, the same poor performance was observed. When the flight units were re-designed and filled to the levels similar to the initial successful DM LHP test, the flight units also successfully fulfilled all requirements. This final flight Acceptance test assessed performance with respect to startup, low power operation, conductance, and control heater power, and steady state control. The results of the testing showed that both LHPs operated within specification. Startup on one of the LHPs was better than the other LHP because of the starter heater placement and a difference in evaporator design. These differences resulted in a variation in the achieved superheat prior to startup. The LHP with

  11. Cold Vacuum Dryer (CVD) Facility Fire Protection System Design Description (SYS 24)

    SciTech Connect

    SINGH, G.

    2000-10-17

    This system design description (SDD) addresses the Cold Vacuum Drying (CVD) Facility fire protection system (FPS). The primary features of the FPS for the CVD are a fire alarm and detection system, automatic sprinklers, and fire hydrants. The FPS also includes fire extinguishers located throughout the facility and fire hydrants to assist in manual firefighting efforts. In addition, a fire barrier separates the operations support (administrative) area from the process bays and process bay support areas. Administrative controls to limit combustible materials have been established and are a part of the overall fire protection program. The FPS is augmented by assistance from the Hanford Fire Department (HED) and by interface systems including service water, electrical power, drains, instrumentation and controls. This SDD, when used in conjunction with the other elements of the definitive design package, provides a complete picture of the FPS for the CVD Facility.

  12. A central low vacuum pipeline system for the disposal of waste anaesthetic gases.

    PubMed

    Burm, A G; Spierdijk, J; Rejger, V; Strokap, H

    1982-04-01

    An independent low vacuum pipeline system for scavenging waste anaesthetic gases is described. The pipeline system has terminal points in several operating and induction rooms. At each terminal point a connection box is installed, eigher in the wall or in a ceiling pendant. Excess gases from the anaesthetic apparatus or the patient ventilator are collected in a reservoir and subsequently sucked through the pipeline system, together with a surplus of air, extracted from the room via openings in the terminal box. The total suction rate is 100 1/min at each terminal box. Once connected, the system needs no looking after by the anaesthetist. Sub-atmospheric and positive pressures, measured at the point of connection to the anaesthetic apparatus are always between -11 Pa and +60 Pa, complying with the current standards. PMID:7091644

  13. Modernization of the control system and the electrical equipment of DSV vacuum arc furnaces

    NASA Astrophysics Data System (ADS)

    Dednev, A. A.; Kisselman, M. A.; Nekhamin, S. M.; Kalinin, V. I.; Koshelev, Yu. N.

    2010-06-01

    The results of modernizing one of the DSV-3.2-G1 arc furnaces at OAO Elektrostal’ Metallurgical Works are presented. New automatic control system ACS DSV-3.2 with functions of maintenance, control, and correction of the main technical parameters of vacuum arc remelting is created. The electric furnace is equipped with a modern visual control system for a heat and a unique inert gas (helium) supply system. The rod motion drive is replaced by a modern drive with frequency control of its motion velocity. New control cabinet and desk made of modern elements are mounted. Melting of a pilot series of EP-718 alloy ingots supports the high quality and reliability of the new control systems.

  14. The CEBAF (Continuous Electron Beam Accelerator Facility) fast shutdown system

    SciTech Connect

    Perry, J.; Woodworth, E.

    1990-09-01

    Because of the high power in the CEBAF beam, equipment must be protected in the event of beam loss. The policy that has been adopted is to require a positive permissive signal from each of several inputs in order to operate the gun that starts the beam. If the permissive is removed, the gun shuts off within 20 {mu}s. The inputs that are now monitored include radiation monitors that detect beam loss directly, vacuum monitors (which also observe the status of various in-line valves), and general input from the rf system, which combines detection of klystron failure, arcs, and rf window high temperature. The system is expandable, so other fault detectors can be added if experience shows their necessity.

  15. Lessons learned on the Ground Test Accelerator control system

    SciTech Connect

    Kozubal, A.J.; Weiss, R.E.

    1994-09-01

    When we initiated the control system design for the Ground Test Accelerator (GTA), we envisioned a system that would be flexible enough to handle the changing requirements of an experimental project. This control system would use a developers` toolkit to reduce the cost and time to develop applications for GTA, and through the use of open standards, the system would accommodate unforeseen requirements as they arose. Furthermore, we would attempt to demonstrate on GTA a level of automation far beyond that achieved by existing accelerator control systems. How well did we achieve these goals? What were the stumbling blocks to deploying the control system, and what assumptions did we make about requirements that turned out to be incorrect? In this paper we look at the process of developing a control system that evolved into what is now the ``Experimental Physics and Industrial Control System`` (EPICS). Also, we assess the impact of this system on the GTA project, as well as the impact of GTA on EPICS. The lessons learned on GTA will be valuable for future projects.

  16. Positron Injector Accelerator and RF System for the ILC

    SciTech Connect

    Wang, J.W.; Adolphsen, C.; Bharadwaj, V.; Bowden, G.; Jongewaard, E.; Li, Z.; Miller, R.; Sheppard, J.C.; /SLAC

    2007-03-28

    Due to the extremely high energy deposition from positrons, electrons, photons and neutrons behind the positron target, and because a solenoid is required to focus the large emittance positron beam, the 1.3 GHz preaccelerator has to use normal conducting structures up to energy of 400 MeV. There are many challenges in the design of the normal-conducting portion of the ILC positron injector system such as obtaining high positron yield with required emittance, achieving adequate cooling with the high RF and particle loss heating, and sustaining high accelerator gradients during millisecond-long pulses in a strong magnetic field. Considering issues of feasibility, reliability and cost savings for the ILC, the proposed design for the positron injector contains both standing-wave (SW) and traveling-wave (TW) L-band accelerator structures. A short version of the new type of the SW section is under fabrication and testing. An updated status report is given. This paper also covers acceleration vs. deceleration for pre-accelerator sections, SW vs. TW structures, as well as longitudinal matching from target to linac and linac to damping ring.

  17. Systems approach to measuring short-duration acceleration transients

    NASA Astrophysics Data System (ADS)

    Schelby, F.

    It is common for failures to occur when attempting to acquire acceleration structural response measurements during crash, impact, and pyrotechnic testing. The structural response of a mechanical system to severe transient loading is commonly measured by accelerometers which are less than ideal. In particular, their amplitude-frequency response has one or more resonant peaks so that the output of the accelerometer may not be an exact replica of the input if the transient input stimulus contains frequencies near these resonant peaks, signal distortion, over-ranging of signal conditioning electronics, or even failure of the sensing element may occur. These and other problems have spurred the development of a new acceleration-measuring system which incorporates the following features; Transduction Element; Connectors; Mounting; Electronics; and Transducer Resonance.

  18. Classroom performance system use in an accelerated graduate nursing program.

    PubMed

    Grimes, Corinne; Joiner Rogers, Glenda; Volker, Deborah; Ramberg, Elizabeth

    2010-01-01

    Many students who enter accelerated nursing programs have not been exposed to the analysis, prediction, and decision-making skills needed by today's RN. To foster practice with complex concepts in the classroom and to give teachers immediate feedback about student in-class mastery of core material, use of an audience participation system within the classroom may be useful. This article reports the implementation of a classroom performance system and the results ofa program evaluation project designed to capture the system's impact on student and faculty satisfaction and student learning outcomes. Project results and implications for further work are presented. PMID:20182157

  19. Hardware-accelerated Components for Hybrid Computing Systems

    SciTech Connect

    Chavarría-Miranda, Daniel; Nieplocha, Jaroslaw; Gorton, Ian

    2008-10-31

    We present a study on the use of component technology for encapsulating platform-specific hardwareaccelerated algorithms on hybrid HPC systems. Our research shows that component technology can have significant benefits from a software engineering pointof- view to increase encapsulation, portability and reduce or eliminate platform dependence for hardwareaccelerated algorithms. As a demonstration of this concept, we discuss our experience in designing, implementing and integrating an FPGA-accelerated kernel for Polygraph, an application in computational proteomics.

  20. Space acceleration measurement system triaxial sensor head error budget

    NASA Astrophysics Data System (ADS)

    Thomas, John E.; Peters, Rex B.; Finley, Brian D.

    1992-01-01

    The objective of the Space Acceleration Measurement System (SAMS) is to measure and record the microgravity environment for a given experiment aboard the Space Shuttle. To accomplish this, SAMS uses remote triaxial sensor heads (TSH) that can be mounted directly on or near an experiment. The errors of the TSH are reduced by calibrating it before and after each flight. The associated error budget for the calibration procedure is discussed here.