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Cold vacuum drying facility design requirements

Description: This release of the Design Requirements Document is a complete restructuring and rewrite to the document previously prepared and released for project W-441 to record the design basis for the design of the Cold Vacuum Drying Facility.
Date: September 24, 1997
Creator: Irwin, J.J.
Partner: UNT Libraries Government Documents Department

APS storage ring vacuum system performance

Description: 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.
Date: June 1, 1997
Creator: Noonan, J.R.; Gagliano, J. & Goeppner, G.A.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Date: January 1, 1995
Creator: Wienands, U.; Daly, E.; Kulikov, A.; Kurita, N.; Nordby, M.; Perkins, C. et al.
Partner: UNT Libraries Government Documents Department

Betatron tune shifts and Laslett image coefficients

Description: The complicated expressions of betatron tune shifts in terms of Laslett image coefficients are explained. The expressions of image coefficients for a centered or off-centered beam inside an elliptical or rectangular vacuum chamber are gathered. Typos in earlier literature are corrected.
Date: July 20, 2001
Creator: Ng, K. Y.
Partner: UNT Libraries Government Documents Department

Surface Impedance and Synchronous Modes

Description: The concept of the surface impedance is applicable to the case, when obstacles on the surface of a vacuum chamber are small compared to characteristic dimensions of the problem. We apply this concept to the calculation of a synchronous mode that can propagate in a tube with slightly corrugated walls. We also show that such a mode can propagate in a pipe with a rough surface, or a perforated pipe with a large number of holes.
Date: July 20, 1999
Creator: Stupakov, Gennady
Partner: UNT Libraries Government Documents Department

ANALYSIS OF BEAM INDUCED PRESSURE INCREASES IN RHIC WARM VACUUM SECTIONS.

Description: With increasing intensity of gold and proton beams during recent RHIC operations, pressure rises of several decades were observed at a few RHIC warm vacuum sections. The pressure increases were analyzed and compared with the beam parameters such as ion species, bunch intensity, total intensity, number ofbunches, bunch spacing and beam loss. Most of these pressure increases were found to be consistent with those induced by either beam loss and/or electron multipacting.
Date: June 2, 2002
Creator: HSEUH,H.C.; SMART,L.A. & ZHANG,S.Y.
Partner: UNT Libraries Government Documents Department

Impedances of Laminated Vacuum Chambers

Description: First publications on impedance of laminated vacuum chambers are related to early 70s: those are of S. C. Snowdon [1] and of A. G. Ruggiero [2]; fifteen years later, a revision paper of R. Gluckstern appeared [3]. All the publications were presented as Fermilab preprints, and there is no surprise in that: the Fermilab Booster has its laminated magnets open to the beam. Being in a reasonable mutual agreement, these publications were all devoted to the longitudinal impedance of round vacuum chambers. The transverse impedance and the flat geometry case were addressed in more recent paper of K. Y. Ng [4]. The latest calculations of A. Macridin et al. [5] revealed some disagreement with Ref. [4]; this fact stimulated us to get our own results on that matter. Longitudinal and transverse impendances are derived for round and flat laminated vacuum chambers. Results of this paper agree with Ref. [5].
Date: June 22, 2011
Creator: Burov, A. & Lebedev, V.
Partner: UNT Libraries Government Documents Department

2$sup 0$K vacuum pumping system for Baseball II

Description: A vacuum pumping system that provides a cryo surface for condensing and freezing of H/sub 2/ gas is described. A closed-loop vacuum system was designed and built at Lawrence Livermore Laboratory to pump down the neutralizer LH/sub e/ dewar with a volurae of 350 l and the lambda point dewar with a LH/sub e/ volume of 250 l. Both of these dewars can be pumped down simultaneously or one at a time. 100% of the H/sub e/ gas is recovered free of contaminations. The vacuum pump can handle 340 SCFM of gas. The LH/sub e/ dewars are pumped down below the lambda point. This condition reduces the LH/sub e/ container wall temperature to 2.1 deg K giving a base pressure of 10/sup -13/ torr for H/sub 2/ gas/sup 2/. To attain a stable condition the LH /sub e/ baths are puuped down to 33 torr or lower to give a surface temperatare of about 2/sup 0/K/sup 3/. The Baseball II helium factlity is a close loop system. The H/sub e/ gas is recovered from all the LH/sub e/ usage point. This gas is accumulated in one of the two 8000 cu ft inflatable gas bags. The gas from the gas bags is compressed into storage tanks at 1800 psig. The gas is purified to 99.99999% and it is liquified at a rate of 100 liquid liters per hour. (auth)
Date: August 20, 1973
Creator: Denhoy, B.S.
Partner: UNT Libraries Government Documents Department

High-power vacuum window in WR10

Description: Results are presented for fabrication and test of a WR10 waveguide window, for use in ultra-high vacuum at 91.4 GHz. Low-power bench measurements are compared with analytic and simulation results. Operation at approximately equal to 4-kW peak power, duty factor 10{sup {minus}6} and 10{sup {minus}9}-scale vacuum is noted.
Date: June 28, 1999
Creator: Hill, Marc E
Partner: UNT Libraries Government Documents Department

ECH mirror interface tank for 110 GHz, 1 MW gyrotron

Description: A 1 MW, 110 GHz gyrotron is to be installed at General Optical Atomics in 1995. A Mirror Optics Unit (MOU) has been Unit designed and built to connect to the existing 110 GHz transmission line system. The unit reduces and directs a 145 mm diameter beam from the gyrotron to a 19 mm diameter beam which is then injected into a 31.8 mm diameter corrugated waveguide of the transmission line system. The unit operates under vacuum and is able to absorb beam spray from the gyrotron. The tank also contains various diagnostics equipment to protect the gyrotron and to determine the amount of energy loss in the tank, and at the window of the gyrotron output. This paper discusses further the design parameters, assembly and installation of the unit in the transmission line system.
Date: October 1, 1995
Creator: O`Neil, R.C.; Callis, R.W.; Cary, W.P.; Doane, J.L.; Gallix, R.; Hodapp, T.R. et al.
Partner: UNT Libraries Government Documents Department

New technologies for a future superconducting proton collider

Description: New more economic approaches are required to continue the dramatic exponential rise in particle accelerator energies as represented by the well- known Livingston plot. The old idea of low-cost, low-field iron dominated magnets in a small diameter pipe may become feasible in the next decade with dramatic recent advances in technology: (1) high T{sub c} superconductors operating at liquid N{sub 2} or H{sub 2} temperatures, (2) advanced tunneling technologies for small diameter, non human accessible tunnels, (3) accurate remote guidance systems for boring machine steering, (4) industrial applications of remote manipulation and robotics, and (5) digitally multiplexed electronics to minimize cables There is an opportunity for mutually beneficial partnerships between the High Energy Physics community and the commercial sector to develop the necessary technology. This will gain public support, a necessary part of the challenge of building a new, very high energy collider.
Date: June 1, 1996
Creator: Malamud, E. & Foster, G.W.
Partner: UNT Libraries Government Documents Department

Gas Composition Transients in the Cold Vacuum Drying (CVD) Facility

Description: The purpose of this document is to evaluate selected problems involving the prediction of transient gas compositions during Cold Vacuum Drying operations. The problems were evaluated to answer specific design questions. The document is formatted as a topical report with each section representing a specific problem solution. The problem solutions are reported in the calculation format specified in HNF-1613, Rev. 0, EP 7.6.
Date: May 10, 2000
Creator: PACKER, M.J.
Partner: UNT Libraries Government Documents Department

Superconducting drift-tube cavity development for the RIA driver.

Description: This paper reports the design and development of two intermediate-velocity superconducting cavities and design of an associated cryomodule for the RIA driver linac. The two cavity types are a 115 MHz, {beta}{sub GEOM} = 0.15 quarter-wave resonant (QWR) cavity, and a 173 MHz, {beta}{sub GEOM} = 0.26 half-wave loaded cavity. Both cavities are well-corrected for dipole and quadrupole asymmetries in the accelerating field. The cryomodule is being designed to incorporate a separate vacuum system for cavity vacuum to provide a particulate-free environment for the superconducting cavities.
Date: September 23, 2002
Creator: Shepard, K. W.; Kelly, M. P. & Fuerst, J. D.
Partner: UNT Libraries Government Documents Department

Transverse resistive wall impedance for multi-layer round chambers

Description: The resistive wall impedance is usually calculated assuming the skin depth being much smaller than the chamber thickness. This approximation is not always correct. In particular, it is not valid when the revolution frequency is very low (as in VLHC [1]), or the surface is coated by a thin conductive layer (as for extraction kickers [2]), or for the coherent effects in the closed orbit motion [3]. A method of analytical calculation of the transverse impedance is developed here for multi-layer vacuum chambers and applied to an arbitrary two-layer structure.
Date: June 11, 2002
Creator: Lebedev, Alexy Burov and Valeri
Partner: UNT Libraries Government Documents Department

Transverse Resistive Wall Impedance for Multi-Layer Flat Chambers

Description: The transverse resistive wall impedance is calculated for arbitrary multi-layer vacuum chambers with a flat geometry. A finite thickness of the metal layer is important at impedance calculations for long machines like VLHC [1], thin coating of elements like injection kickers [2] and a closed orbit coherent stability analysis [3]. This paper uses ideas of our similar consideration for round vacuum chambers [4].
Date: June 11, 2002
Creator: Lebedev, Alexy Burov and Valeri
Partner: UNT Libraries Government Documents Department

Advanced light source vacuum policy and vacuum guidelines for beamlines and experiment endstations

Description: The purpose of this document is to: (1) Explain the ALS vacuum policy and specifications for beamlines and experiment endstations. (2) Provide guidelines related to ALS vacuum policy to assist in designing beamlines which are in accordance with ALS vacuum policy. This document supersedes LSBL-116. The Advanced Light Source is a third generation synchrotron radiation source whose beam lifetime depends on the quality of the vacuum in the storage ring and the connecting beamlines. The storage ring and most of the beamlines share a common vacuum and are operated under ultra-high-vacuum (UHV) conditions. All endstations and beamline equipment must be operated so as to avoid contamination of beamline components, and must include proper safeguards to protect the storage ring vacuum from an accidental break in the beamline or endstation vacuum systems. The primary gas load during operation is due to thermal desorption and electron/photon induced desorption of contaminants from the interior of the vacuum vessel and its components. The desorption rates are considerably higher for hydrocarbon contamination, thus considerable emphasis is placed on eliminating these sources of contaminants. All vacuum components in a beamline and endstation must meet the ALS vacuum specifications. The vacuum design of both beamlines and endstations must be approved by the ALS Beamline Review Committee (BRC) before vacuum connections to the storage ring are made. The vacuum design is first checked during the Beamline Design Review (BDR) held before construction of the beamline equipment begins. Any deviation from the ALS vacuum specifications must be approved by the BRC prior to installation of the equipment on the ALS floor. Any modification that is incorporated into a vacuum assembly without the written approval of the BRC is done at the user`s risk and may lead to rejection of the whole assembly.
Date: August 1, 1995
Creator: Hussain, Z.
Partner: UNT Libraries Government Documents Department

Disruptions, loads, and dynamic response of ITER

Description: Plasma disruptions and the resulting electromagnetic loads are critical to the design of the vacuum vessel and in-vessel components of the International Thermonuclear Experimental Reactor (ITER). This paper describes the status of plasma disruption simulations and related analysis, including the dynamic response of the vacuum vessel and in-vessel components, stresses and deflections in the vacuum vessel, and reaction loads in the support structures.
Date: December 31, 1995
Creator: Nelson, B.; Riemer, B.; Sayer, R.; Strickler, D.; Barabaschi, P.; Ioki, K. et al.
Partner: UNT Libraries Government Documents Department

ITER vacuum vessel fabrication plan and cost study (D 68) for the international thermonuclear experimental reactor

Description: ITER Task No. 8, Vacuum Vessel Fabrication Plan and Cost Study (D68), was initiated to assess ITER vacuum vessel fabrication, assembly, and cost. The industrial team of Raytheon Engineers & Constructors and Chicago Bridge & Iron (Raytheon/CB&I) reviewed the current vessel basis and prepared a manufacturing plan, assembly plan, and cost estimate commensurate with the present design. The guidance for the Raytheon/CB&I assessment activities was prepared by the ITER Garching Work Site. This guidance provided in the form of work descriptions, sketches, drawings, and costing guidelines for each of the presently identified vacuum vessel Work Breakdown Structure (WBS) elements was compiled in ITER Garching Joint Work Site Memo (Draft No. 9 - G 15 MD 01 94-17-05 W 1). A copy of this document is provided as Appendix 1 to this report. Additional information and clarifications required for the Raytheon/CB&I assessments were coordinated through the US Home Team (USHT) and its technical representative. Design details considered essential to the Task 8 assessments but not available from the ITER Joint Central Team (JCT) were generated by Raytheon/CB&I and documented accordingly.
Date: January 1, 1995
Partner: UNT Libraries Government Documents Department