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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

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

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

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

Vacuum Technology

Description: 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.
Date: October 15, 2004
Creator: Biltoft, P. J.
Partner: UNT Libraries Government Documents Department

A simple, high-yield, apparatus for NEG coating of vacuum beamline elements

Description: Non-Evaporable Getter (NEG) materials are extremely useful in vacuum systems for achieving Ultra High Vacuum. Recently, these materials have been used to coat the inner surfaces of vacuum components, acting as an internal, passive, vacuum pump. We have constructed a low cost apparatus, which allows coating of very small diameter vacuum tubes, used as differential pumping stages. Despite the relative ease of construction, we are routinely able to achieve high coating yields. We further describe an improvement to our system, which is able to achieve the same yield, at an even lower complexity by using an easily manufactured permanent magnet arrangement. The designs described are extendible to virtually any combination of length and diameter of the components to be coated.
Date: December 1, 2010
Creator: Ron, Guy; Oort, Ron & Lee, Daniel
Partner: UNT Libraries Government Documents Department

Vacuum Consideration Pertaining to Bellows Changes on Debuncher Tanks

Description: It has been proposed that the stochastic cooling tanks in the Debuncher be modified so that their position can be changed remotely by installing motor driven stands. The present bellows that connect the tanks to the beam pipe vacuum chamber does not have enough radial movement to allow the movement required of the tanks. In order for this proposal to be enacted, the existing bellows will have to be replaced. The present bellows is a formed bellows 5 1/2-inch I.D. x 2-inch long, it will be replaced by a welded bellows 4-inch I.D. x 4-inch long. Due to the smaller size of the replacement bellows, its effect on the performance of the Debuncher Vacuum System must be examined. The areas of concern are: pumpdown time, pressure attained by turbos, and pressure in the high vacuum range.
Date: November 13, 1985
Creator: Klen, J.
Partner: UNT Libraries Government Documents Department

Impedance Calculations of Non-Axisymmetric Transitions Using the Optical Approximation

Description: In a companion report, we have derived a method for finding the impedance at high frequencies of vacuum chamber transitions that are short compared to the catch-up distance, in a frequency regime that--in analogy to geometric optics for light--we call the optical regime. In this report we apply the method to various non-axisymmetric geometries such as irises/short collimators in a beam pipe, step-in transitions, step-out transitions, and more complicated transitions of practical importance. Most of our results are analytical, with a few given in terms of a simple one dimensional integral. Our results are compared to wakefield simulations with the time-domain, finite-difference program ECHO, and excellent agreement is found.
Date: March 6, 2007
Creator: Bane, K.L.F.; Stupakov, G.; /SLAC; Zagorodov, I. & /DESY
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Date: January 25, 2006
Creator: Shen, S
Partner: UNT Libraries Government Documents Department

Preparation of a glovebox for casting enriched plutonium.

Description: Objectives: Prepare existing glovebox for casting, heat treating and storing enriched plutonium, Upgrade seismic systems to reduce dispersion hazard, Upgrade atmospheric systems to reduce oxidation of plutonium, Upgrade vacuum system to prevent oxidation, InstalI/upgrade induction heating systems to melt plutonium and heat mold
Date: January 1, 2002
Creator: Ronquillo, R. D. (Richard D.); Trujillo, C. M. (Chris M.) & Trujillo, C. C. (Claudette C.)
Partner: UNT Libraries Government Documents Department

Pressure Model for the Vacuum System for the Electron Gun and Injector for LCLS Final Design Report

Description: The vacuum system of the injector for the Linac Coherent Light Source (LCLS) 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 vacuum system layout and detailed analyses for the injector are presented in this final 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.
Date: April 28, 2006
Creator: Tung, L S & Eriksson, L
Partner: UNT Libraries Government Documents Department

Multilayer High-Gradient Insulators

Description: High voltage systems operated in vacuum require insulating materials to maintain spacing between conductors held at different potentials, and may be used to maintain a nonconductive vacuum boundary. Traditional vacuum insulators generally consist of a single material, but insulating structures composed of alternating layers of dielectric and metal can also be built. These ''High-Gradient Insulators'' have been experimentally shown to withstand higher voltage gradients than comparable conventional insulators. As a result, they have application to a wide range of high-voltage vacuum systems where compact size is important. This paper describes ongoing research on these structures, as well as the current theoretical understanding driving this work.
Date: November 15, 2006
Creator: Harris, J R; Anaya, R M; Blackfield, D; Chen, Y -; Falabella, S; Hawkins, S et al.
Partner: UNT Libraries Government Documents Department

LCLS XTOD Tunnel Vacuum System (XVTS)

Description: 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.
Date: November 4, 2005
Creator: Beale, R; Duffy, P; Kishiyama, K; Mckernan, M; McMahon, D; Lewis, S et al.
Partner: UNT Libraries Government Documents Department

An Analysis of Accumulator Ring Pressure Date

Description: This note summarizes and analyzes the Accumulator Ring's pressure data taken during the recent commissioning run (March-October, 1985) and during the three week interval immediately after the end of the commissioning run. Emphasis is placed upon the questions raised in reference [1], viz.: (1) What is the ultimate vacuum attainable? (2) How do we calculate the 'effective-pressure' for beam lifetime estimates from the ion gauge data? (3) What is the required sublimation schedule to maintain adequate vacuum?
Date: January 9, 1986
Creator: Gormley, M.
Partner: UNT Libraries Government Documents Department