During the assembly of the Alternating Phase Focusing cavity for the PIGMI Prototype proton accelerator, recurring failures of drift-tube braze joints occurred. In the fabrication technique, a torch braze was used to attach the stems to both the drift-tub...
National Technical Information Service (NTIS)
During the assembly of the Alternating Phase Focusing cavity for the PIGMI Prototype proton accelerator, recurring failures of drift-tube braze joints occurred. In the fabrication technique, a torch braze was used to attach the stems to both the drift-tube body and the stem termination; all materials used were stainless steel. The ...
Energy Citations Database
The objective of this study was to ascertain the condition of braze joints and cooling water hardware from an accelerator section after prolonged use. Metallographic analysis was used to examine critical sites on an accelerator section that had been in us...
The disclosure relates to a drift tube suspension for high intensity linear accelerators. The system comprises a series of box-sections girders independently adjustably mounted on a linear accelerator. A plurality of drift tube holding stems are individually adjustably ...
Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift ...
DOEpatents
The design study is described for the drift tubes of the linear accelerator for the injector of a 1-Bev electron synchrotron. (auth)
A linear accelerator system includes a plurality of post-coupled drift-tubes wherein each post coupler is bistably positionable to either of two positions which result in different field distributions. With binary control over a plurality of post couplers, a significant accumlative effect in the resulting field distribution is achieved yielding a ...
The Yale heavy-ion linear accelerator consists of a Cockcroft-Walton injector,a grid-focussed drift tube section, and a strong focussing drift tube section for acceleration of ions from 0.045 to 0.14c. The latter section contains 67 drift ...
... a dc beam (0 - 100pa) or a pulsed beam (0 ... silicon and GaP 8 was found to be very fast. ... the dewar can be decoupled from the accelerator drift tube ...
DTIC Science & Technology
The longitudinal particle dynamics in a linear accelerator in the acceleration regime of two waves with multiple frequency without regard for space charge is considered. The accelerating structure of a cavity resonator with 100 MeV drift tubes of is chose...
... Accession Number : AD0194887. Title : THE NONDESTRUCTIVE TESTING OF BRAZED JOINTS. Corporate Author : Personal ...
... Title : THE CORROSION RESISTANCE OF BRAZED JOINTS IN TITANIUM ALLOYS IN HYDROCHLORIC ACID SOLUTIONS,. Corporate Author : ...
A method previously developed to obtain the parameters, fields, and losses for linear accelerator cells loaded with shaped drift tubes was used for those shapes generated by a two-charge pair located on the axis of the cell. The apcussed and numerical results are given. (M.C.G.)
A heavy particle linear accelerator employing rf fields for transverse and ongitudinal focusing as well as acceleration. Drift tube length and gap positions in a standing wave drift tube loaded structure are arranged so that particles are subject to ...
A high power pulsed electron beam is produced in a system comprised of an electron gun having a heated cathode, control grid, focus ring, and a curved drift tube. The drift tube is maintained at a high positive voltage with respect to the cathode to accelerate electrons passing through the ...
A broad-band beam bunther is disclosed, comprising an evacuated housing, an electron gun therein for producing an electron beam, a buncher cavity having entrance and exit openings through which the beam is directed, grids across such openings, a source providing a positive DC voltage between the cavity and the electron gun, a drift tube through which the ...
A broad-band beam buncher is disclosed, comprising an evacuated housing, an electron gun therein for producing an electron beam, a buncher cavity having entrance and exit openings through which the beam is directed, grids across such openings, a source providing a positive DC voltage between the cavity and the electron gun, a drift tube through which the ...
DOE Information Bridge
In the Laser Controlled Collective Accelerator, an intense electron beam is injected at a current above the vacuum space charge limit into an initially evacuated drift tube. A plasma channel, produced by time-sequenced, multiple laser beam ionization of a solid target on the drift tube wall, ...
An arrangement for the drift tubes in a linear accelerator is described whereby each drift tube acts to shield the particles from the influence of the accelerating field and focuses the particles passing through the tube. In one embodiment the ...
Vibrations induced in accelerator structures can cause particle-beam jitter and alignment difficulties. Sources of these vibrations may include pump oscillations, cooling-water turbulence, and vibrations transmitted through the floor to the accelerator structure. Drift tubes (DT) in a drift ...
Ramped accelerating gradients in drift-tube linacs are made possible by post couplers with extreme differential coupling between adjacent accelerating gaps. By bringing the energy of the beam up through ramping, better overall control of longitudinal emittance can be accomplished and a more compact accelerator achieved. Such a machine ...
An electron beam with a virtual cathode (VC) transported in a two-section drift tube of a SINUS-7 high-current electron accelerator has been studied. The dependence of the VC velocity on the injected current has been experimentally determined for the first time. It is established that the VC motion in the drift ...
NASA Astrophysics Data System (ADS)
The drift tubes for the linac are ellipsoidal in shape with a length varying from 1 to 15 inches and:maximum diameter of about 9 inches. The system of support provides adjustments in orthogonal coordinates parallel to the directions in which aligning measurements are to be taken as well as providing for all adjustments necessary. (W.D.M.)
The assembly drawing AD 436-011-00-R1 and subsequent drawings called out provide the data and specifications for constructing the drift tube used in place of a future accelerating cavity on the SPEAR Storage Ring. This is a straight section serving only to complete the vacuum pipe for the circulating electrons and positrons.
design and analysis of brazed joints has not been developed. This paper provides an ... Margin of Safety (MS) of complex brazed joints produced no satisfactory ...
NASA Website
A high power pulsed electron beam system for annealing semiconductors is comprised of an electron gun having a heated cathode, control grid and focus ring for confining the pulsed beam of electrons to a predetermined area, and a curved drift tube. The drift tube and an annular Faraday shield between the focus ring ...
A method has been developed to analyze the beam dynamics of the radiofrequency quadrupole accelerating structure. Calculations show that this structure can accept a dc beam at low velocity, bunch it with high capture efficiency, and accelerate it to a velocity suitable for injection into a drift tube linac.
The Ground Test Accelerator (GTA) has the objective of verifying much of the technology required for producing high-brightness, high-current H[sup [minus
The acceleration of ions to many times the electron beam energy when an intense relativistic electron beam is injected through a localized ion source into an otherwise evacuated drift tube has been theoretically and experimentally studied. We present a si...
A study is presented of the phase oscillations in drift tube and traveling wave linacs, fixed field circular accelerators, and synchrotrons. Unified notation and method development are used to exhibit the oscillation similarities and differences. (J.R. D.)
A coupled-cavity drift-tube linac (CCDTL) combines features of the Alvarez drift-tube linac (DTL) and the {pi}-mode coupled-cavity linac (CCL). In one embodiment, each accelerating cavity is a two-cell, 0-mode DTL. The center-to-center distance between accelerating gaps is {beta}{lambda}, where {lambda} is the ...
A coupled-cavity drift-tube linac (CCDTL) combines features of the Alvarez drift-tube linac (DTL) and the .pi.-mode coupled-cavity linac (CCL). In one embodiment, each accelerating cavity is a two-cell, 0-mode DTL. The center-to-center distance between accelerating gaps is .beta..lambda., where .lambda. is the ...
A short, high-power linac structure has been designed and is being built; it incorporates a ramped accelerating field for matching a radio-frequency quadrupole (RFQ) to a high-gradient drift-tube linac (DTL). The tank is made of aluminum and can operate at high duty factor. The drift tubes are copper and use new ...
... Accession Number : ADD121135. Title : The Mechanical Properties of Brazed Joints in Niobium Alloys,. Corporate Author : ...
... Accession Number : AD0297526. Title : Plastic Deformation of Thin Brazed Joints in Shear. Corporate Author : MASSACHUSETTS ...
... Accession Number : AD0194301. Title : MAGNETIC PARTICLE TESTING OF BRAZED JOINTS IN NONMAGNETIC STAINLESS. Corporate Author : ...
... Accession Number : ADD327333. Title : FLAW SIZE ESTIMATION IN BRAZED JOINTS BY ULTRASONIC TESTING. Corporate Author : ...
... Accession Number : AD0180655. Title : Compatibility of Brazed Joints With Potassium and Vacuum. Corporate Author : ...
... Accession Number : ADD878882. Title : CORROSION OF BNI BRAZED JOINTS IN STAINLESS STEELS. Corporate Author : ...
The Ground Test Accelerator (GTA) had the objective of producing a high-brightness, high-current H- beam. The major accelerator components were a 35 keV injector, a Radio Frequency Quadrupole, an intertank matching section, and a drift tube linac (DTL), consisting of 10 modules. This paper discusses the phase-scan ...
When an intense electron beam is injected into an evacuated drift cavity placed in a strong longitudinal magnetic field a virtual cathode will form if the beam current exceeds the space charge limiting current. If the drift tube is flared, the virtual cat...
An experimental demonstration confirming the beam-dynamics of a Ramped-Gradient Drift-Tube Linac (RGDTL) was performed at Los Alamos National Laboratory. The RGDTL was designed to optimize on the requirements of maximum beam acceleration, minimum longitud...
A scale model of the Fusion Materials Irradiation Test Facility (FMIT) 80-MHz drift-tube linac (DTL) was constructed to investigate the tuning procedure. The model DTL has 16 cells and was constructed to have the accelerating mode at 367 MHz. The mode spectrum was measured for various post penetrations, and field profiles of the modes were recorded. The ...
The major attractions of the pulsed drift-tubes are that they are non-resonant structures and that they appear suitable for accelerating a very high current bunch at low energies. The mechanical tolerances of the non-resonant structure are very loose and the cost per meter should be low; the cost of the transport system is expected to be the major cost. ...
Extension of the conventional 2 pi structure for particle acceleration to 200 Mev or higher requires minimization of power losses by optimizing cavity and drift-tube parameters. Using a previously developed method, an optimization of the cavity drift-tube dimensions was made at 200 Mc and at energies of 50, 100, 150, and 200 Mev to give minimum ...
There is a program requirement to produce sound brazed joints between stainiess steel and copper metal components that will remain sound after long time exposure to a high vacuum environment at a temperature of approximately 1000 deg F. Results are described of a microprobe study of one of the promising brazed ...
The influence of corrosion on the bond strength of different brazed joints commonly used in dentistry has been investigated by means of accelerated immersion tests in artificial saliva buffered at pH 2, and in Ringer's solution, both kept at 37 degrees C. Two Co-Cr base metal alloys were brazed with a gold and a non-precious alloy. ...
PubMed
In drift tube linacs a beam energy spread results form the finite beam size. Radial variation of the axial accelerating field induces a beam energy spread, which, in general, will accumulate as the beam passes through successive drift tubes. This paper shows that under some conditions of ...
New permanent magnets for quadrupole focusing make possible smaller drift tubes in drift-tube linacs (DTLs), resulting in higher shunt impedance. However, ordinary post couplers cannot stabilize a DTL whose drift-tube-to-wall spacing exceeds one-quarter wavelength (lambda/4) by more than a few per cent for the ...
The construction and assembly of a Cs ion injector consisting of a pulsed source and 3 pulsed drift tubes has been complete since April 1980. The measurement program, underway since then to characterize the beam, has been interspersed with the development of diagnostic equipment. The Cs contact ionization source and each of the 3 drift ...
A klystron includes a source for emitting at least one electron beam, and an accelerator for accelarating the beam in a given direction through a number of drift tube sections successively aligned relative to one another in the direction of the beam. A number of electrostatic quadrupole arrays are successively aligned relative to one ...
A source is described of coherent radiation in the infrared, visible light and ultraviolet frequency range comprising: an evaluated drift tube having an input end for receiving a beam of relativistic electrons and an output end for providing coherent radiation; electron supply means for providing a beam of relativistic electrons to the ...
A linear accelerator technology was developed that makes pi-meson (pion) generation possible for cancer therapy in the setting of a major hospital center. This technology uses several major inventions in particle accelerator science such as an accelerator system called the radio frequency quadrupole FQ), and permanent magnet ...
A prototype permanent-magnet drift tube quadrupole with adjustable field strength has been constructed and tested. The magnet uses iron pole pieces to provide the required field shape along with rare earth permanent-magnet material (samarium cobalt) to energize the magnet. A unique feature of the configuration is the adjustability of the field, ...
Metallographic examination of braze joints involves standard metallographic procedures with a need for special attention to some unique characteristics of braze joints. These unique characteristics include very thin joints and dissimilar metal combination...
Orbit correction has long been an essential feature of circular accelerators, storage rings, multipass linacs, and linear colliders. In a drift tube linear accelerator (DTL) such as the H- Linac at Fermilab, beam position monitors (BPMs) and dipole corrector magnets can only be located in between ...
An acceleration system is described which allows one to accelerate high currents of ions at very low velocities. The main principle is to utilize an array of electrostatic quadrupoles in an rf linac drift tube, rather than a single magnetic quadrupole, as is usually the case. Because electrostatic quads can be ...
The acceleration of ions to many times the electron beam energy when an intense relativistic electron beam is injected through a localized ion source into an otherwise evacuated drift tube has been theoretically and experimentally studied. We present a simple picture of the acceleration process obtained using a ...
A proposed linear accelerator is described whose beam energy spread is not more than a few tenths of a per cent. Such an accelerator would provide a beam which is usable as an injector for alternating-gradient synchrotrons. The particles are accelerated from low energy in many stages with comparatively low energy per stsge. ...
The first mention of linear acceleration was in a paper by G. Ising in 1924 in which he postulated the acceleration of positive ions induced by spark discharges which produced electric fields in gaps between a series of {open_quotes}drift tubes{close_quotes}. Ising apparently was not able to demonstrate his ...
PIGMI (Pion Generator for Medical Irradiations) is a compact linear proton accelerator designed for a hospital environment. The prototype of the low energy section of PIGMI has been designed and is being fabricated at the Los Alamos Scientific Laboratory. It is an accelerator design which makes use of several advanced or innovative technologies. The PIGMI ...
An ion acceleration mechanism is proposed in which ions are trapped and accelerated by a negative energy space charge wave. Under certain conditions, an electron beam propagating down a slowly converging metal guide can be accelerated. A low phase velocity space charge wave initiated at the large radius end of the guide, because it is ...
Since the start of operation of the Large Hadron Collider (LHC) at CERN on 20 November 2009, the instantaneous luminosity is steadily increasing. The muon spectrometer of the ATLAS detector at the LHC is instrumented with trigger and precision tracking chambers in a toroidal magnetic field. Monitored Drift-Tube (MDT) chambers are employed as precision tracking chambers, ...
E-print Network
... Accession Number : ADD252506. Title : Thermal Residual Stresses in Ceramic-to-Metal Brazed Joints. Descriptive Note : Journal article,. ...
... Accession Number : ADD117121. Title : The Impact Strength of Brazed Joints in High Strength Steels,. Corporate Author : ...
... PROPERTIES OF BRAZED JOINTS IN THE 12Kh18N10T STEEL AND BETWEEN THE 12Kh18N10T STEEL AND COPPER M2 IN THE ...
... Title : THE CORROSION RESISTANCE OF BRAZED JOINTS IN STEELS 20 AND 08Kh18N10T USED IN THERMAL POWER PLANTS,. ...
... Title : Study on Mechanical Properties of Ti Alloy Brazed Joint with Newly Developed Pd Alloys and Other High Temperature Filler Metals. ...
... Accession Number : ADD116735. Title : Strength of High Temperature Brazed Joints--Influence of Brazing Parameters,. Corporate Author : ...
... Title : Strains in, and the Nature of Failure of, Brazed Joints in the 08Kh18N10T Steel in Structures of Thermal Power Plant,. Corporate Author : ...
... Accession Number : ADD116734. Title : Static and Dynamic Crack Toughness of Brazed Joints of Inconel 718 Nickel-Base Alloy,. Corporate Author : ...
... Accession Number : ADD108447. Title : Rene' 95 Brazed Joint Metallurgical Evaluation Program,. Descriptive Note : Final Rept. Jan 71-Jun 72,. ...
A visual inspection was made of all brazed joints, using 10 power magnification for external ... A l l brazed joints were radiographically inspected. This ...
... Title : HAYNES 188/NICROBRAZE 30 BRAZE JOINT AND HAYNES 188 TENSILE TESTS - IR AND D SPACE SHUTTLE. ...
Prediction of failure in brazed joints subjected to complex loading conditions continues ... used as a lower bound FAD for 304SS-silver brazed joints. ...
of Brazed Joints in Metal-Composite System. M. Singh and G.N. Morscher ..... Mechanical Testing of Brazed Joints. Tube Tensile Test. Butt Strap Tensile Test ...
... Accession Number : ADD337396. Title : Dynamic Fracture Properties of Inco 625 Braze Joint,. Corporate Author : Personal Author(s) : Maiti, Ranen. ...
... Accession Number : ADD134498. Title : Distribution of Boron in Brazed Joints in Creep-Resisting Nickel Alloys,. Descriptive Note : Journal Article,. ...
... Accession Number : ADD108438. Title : Corrosion of BAg Brazed Joints in Stainless Steel,. Corporate Author : Personal Author(s) : Kawakatsu,I. ...
... Accession Number : ADD137548. Title : Corrosion Resistance of High-Temperature Brazed Joints in Organic and Aqueous Solutions,. ...
... Accession Number : ADD451150. Title : CERAMIC MATRIX COMPOSITE-METAL BRAZED JOINTS. Corporate Author : ...
... Accession Number : AD0744459. Title : Bronze-Brazed Joints for Sealing Rebar Penetrations of Electromagnetic Pulse Shields. ...
... Accession Number : ADD117547. Title : Brazed Joint Strength of Stainless Steel with Nickel Base Filler Metals,. Corporate Author : ...
The Ground Test Accelerator (GTA) has the objective of verifying much of the technology required for producing high-brightness, high-current H{sup {minus}} beams. GTA commissioning is staged to verify the beam-dynamics design of each major accelerator component as it is brought on-line. The major components are the 35-keV H{sup {minus}} injector, the ...
The objective of this study was to ascertain the condition of braze joints and cooling water hardware from an accelerator section after prolonged use. Metallographic analysis was used to examine critical sites on an accelerator section that had been in use for more than 30 years. The end flange assembly showed no ...
The heart of the Los Alamos Neutron Science Center (LANSCE) is a pulsed linear accelerator that is used to simultaneously provide H+ and H- beams to several user facilities. This accelerator contains two Cockcroft-Walton style injectors, a 100-MeV drift tube linac and an 800-MeV coupled cavity linac. This ...
The PARMILA code, which originated in the 1960s for designing drift-tube linacs (DTLs), now designs and simulates the performance of many types of rf linear accelerator. The structure types include the DTL, coupled-cavity drift-tube linac (CCDTL), conventional coupled-cavity linac (CCL), and several types of superconducting linac. This ...
This patent pertains to pulse modifying apparatus and, more particularly, describes a device to provide a rise time and time base expander for signal pulses having a very short duration. The basic element of the device is a vacuum tube comprising a charged particie beam, grid control means, an accelerating electrode, a drift ...
At Los Alamos, a short, lightweight drift-tube linac (DTL) has been designed. This accomplishment is possible by varying the accelerating gradient from 2 MV/m at the RFQ end to 4.4 MV/m at the output end, with the gradient rising as a cubic polynomial. The object of raising the gradient to such a high level is to reduce the length of the proposed 50-MeV ...
A klystron includes a source for emitting at least one electron beam, and an accelerator for accelerating the beam in a given direction through a number of drift tube sections successively aligned relative to one another in the direction of the beam. A number of electrostatic quadrupole arrays are successively ...
The NO?A Experiment will construct a detector optimized for electron neutrino detection in the existing NuMI neutrino beam. The NuMI beam line is capable of operating at 400 kW of primary beam power and the upgrade will allow up to 700 kW. Ceramic beam tubes are utilized in numerous kicker magnets in different accelerator rings at Fermi National ...
The need for structures that are resistant to damage for 14 MeV neutrons, are bakeable, and that can be closely packed together, has resulted in the intensive development of rectangular brazed ceramic insulators for ion accelerators. The development of two candidate materials, machinable glass ceramic and alumina, is described along with the ceramic-to-metal brazing techniques ...
Twenty-three laced permanent magnet quadrupole drift tube magnets have been constructed, tested, and installed in the SuperHILAC heavy ion linear accelerator at LBL, marking the first accelerator use of this new type of quadrupole. The magnets consist of conventional tape-wound quadrupole electromagnets, using iron ...
A fundamental experiment in gravity proposed by us, is the measurement of the gravitational force on antimatter. This measurement would constitute the first direct test of the Weak Equivalence Principle (WEP) for antimatter. The availability of low-energy antiprotons at CERN has made such an experiment feasible, and a proposal to carry out such a measurement has been accepted by the CERN Program ...
A variety of accelerator designs are being considered for the Accelerator Production of Tritium (APT) project at Alamos National Laboratory. Because activation of the structural components of the accelerator is considered a major radiation protection issue, we have developed a computational methodology to estimate quantitatively ...
... drift tube. The drift tube ... path of the electrons will constantly increase in radius as the electron drifts across the tube* This changs in radius can be ...
... Accession Number : ADD326245. Title : ULTRASONIC EXAMINATION OF SOLDERED AND BRAZED JOINTS. Corporate Author : ...
... THE BRAZE JOINT ON ELECTRICAL CONTACT ASSEMBLIES, WITH ... AND INHOMOGENEOUS AREAS IN BRAZED CONTACTS THAT RUN ...
... Title : THE METALLOGRAPHIC INVESTIGATION OF BRAZED JOINTS IN NICKEL BASE ALLOYS USING VARIOUS TECHNIQUES FOR THE ...
... REASONS FOR THE FORMATION OF FLUX INCLUSIONS ON MACHINED SURFACES OF TELESCOPIC BRAZED JOINTS ARE DETERMINED. ...
... Accession Number : AD0275282. Title : TENSILE DEFORMATION AND FRACTURE OF BRAZED JOINTS. Corporate Author ...
... IN NONDESTRUCTIVE EVALUATION OF DIFFERENT BONDS OF LAYERED STRUCTURE SUCH AS ADHESIVE AND BRAZED JOINTS. ...
... Accession Number : ADD321067. Title : INVESTIGATIONS OF ULTRASONIC TESTING OF BRAZED JOINTS. Corporate Author : ...
... Hochtemperatur-Lotverbindungen (Structural Investigations on Mechanically and Thermally Stressed High Temperature Brazed Joints),. ...
... Title : EVALUATION OF THE FATIGUE BEHAVIOR OF HIGH TEMPERATURE BRAZED JOINTS USING ACOUSTIC EMISSION ANALYSIS. ...
... Title : CONTRIBUTION TO CHARACTERIZE THE PROPERTIES OF HIGH-TEMPERATURE BRAZED JOINTS. Corporate Author : ...
... Title : APPLICATION OF INTERFERENCE LAYER TECHNIQUES TO BRAZED JOINTS AND THERMAL SPRAYED COATINGS. Corporate Author : ...
... Title : AN ULTRASONIC TECHNIQUE FOR EVALUATION OF HEAT-EXCHANGER BRAZED JOINTS. Corporate Author : ...
Metallographic examination of braze joints involves standard metallographic procedures with a need for special attention to some unique characteristics of braze joints. These unique characteristics include very thin joints and dissimilar metal combinations. The thin joint geometry sometimes requires special ...
Cancer therapy synchrotrons profit from single turn injection in terms of size, costs and easy operation. The MEdically Dedicated EBIS (MedEBIS), built in Frankfurt, will deliver short (~1.5 mu s) and intense (~1.3 mA) pulses of highly charged light ions (C, N, O) to meet the requirements for therapy facilities. The MedEBIS operates with an electron beam of 400 mA at 5 keV and a ratio of beam to ...
As part of the Low-Energy Demonstration Accelerator (LEDA) portion of the Advanced Accelerator Applications (AAA) project we have fabricated and will perform high-power RF tests on Section 2 of the 700-MHz Coupled-Cavity Drift-Tube Linac (CCDTL). This CCDTL section contains six, two-gap accelerating cells. This ...
A new linear-accelerator technology has been developed that makes pi-meson (pion) generation possible for cancer therapy in the setting of a major hospital center. This technology uses several new major inventions in particle accelerator science-such as a new accelerator system called the radio-frequency quadrupole (RFQ), and ...
To investigate the performance that can be achieved for low energy heavy ion particle acceleration, a two megahertz low beta linac is being built. This structure, intended for acceleration of 260 keV xenon or 400 keV mercury, is comprised of a quarter wavelength parallel plate resonator used to support drift tubes ...
The properties of using periodically rippled waveguides as wakefield accelerators are investigated. An analysis is performed in the ultrarelativistic limit which accurately predicts the amplitude, wavelength of the wakefield, and their dependences on waveguide and drive beam parameters. These devices are found to have the properties that the synchronous transverse wake ...
Thermal management, resonance control, and reliability requirements become predominant when designing ``conventional`` copper coupled- cavity linac (CCL) structures for very high duty factors and accelerating fields. Whereas the outer body of the coupled-cavity drift-tube linac (CCDTL) is in most ways comparable to the CCL, the cooling and support of the ...
By using a photocathode instead of a thermionic cathode in a klystron, the possibility exists to make very short low energy spread bunches of high efficiency. However, there is a fundamental limit to the efficiency of a conventional output cavity, such as the one used in the SLAC XK-5 klystron. The fringing electric field in the drift tube acts on the beam ...
An experiment is being developed to measure the acceleration of the antiproton in the gravitational field of the earth. Antiprotons of a few MeV from the LEAR facility at CERN will be slowed, captured, cooled to a temperature of about 10 K, and subsequently launched a few at a time into a drift tube where the effect of gravity on their ...
High levels of coherent current and energy oscillations appeared on an intense relativistic electron beam traversing a smooth drift tube in which two or more coaxial cavities were inserted. The frequency of oscillation depended strongly on the geometry of the drift region but only weakly on beam current and voltage. The frequency spectrum of modulation was ...
Los Alamos National Laboratory is building room-temperature rf accelerating structures for the Spallation Neutron Source (SNS). These structures, for H{sup -} ions, consist of six 402.5-MHz, 2-MW drift-tube linac (DTL) tanks from 2.5 to 87 MeV followed by four 805-MHz, 4-MW coupled-cavity linac (CCL) modules to 186 MeV. The DTL uses permanent magnet ...
We have carried out laboratory tests to measure the ageing of a wire tube due to pollutants outgassed by various materials. The tested materials are those used in the barrel muon drift tubes of the CMS experiment at LHC. An X-ray gun irradiated the test tube to accelerate the ageing process. No ageing effect has been measured for a ...
We have carried out laboratory test to measure the ageing of a wire tube due to pollutant outgassed by various materials. The tested materials are those used in the muon barrel drift tubes. An X-ray gun irradiated the test tube to accelerate the ageing process. No ageing effect has been measured for a period equivalent to 10 years of ...
>A particle-beam tracking and correcting circuit is described. Beam induction electrodes are placed on either side of the beam, and potentials induced by the beam are compared in a voltage comparator or discriminator. This comparison produces an error signal which modifies the fm curve at the voltage applied to the drift tube, thereby ...
The PARMILA code was originally developed as a numerical tool to design and simulate the beam performance of the drift-tube linac (DTL). The authors have extended PARMILA to the design of both the coupled-cavity linac (CCL) and the coupled-cavity drift-tube linac (CCDTL). They describe the new design and simulation features associated with these linac structures and ...
RADLAC II produces a high-current annular electron beam which will be used to explore lead pulse stability and channel tracking. These experiments require that the beam be extracted from the vacuum region at the end of the accelerator into a drift tube containing air. This paper describes computational studies of the extraction process ...
A beam buncher has been designed, fabricated, and installed on the accelerator test stand (ATS) to match the 2-MeV output beam of a 425-MHz H sup - radio-frequency quadrupole (RFQ) into a 425-MHz drift-tube linac (DTL). The buncher configuration provides ...
The Fermilab Linac Upgrade has increased the energy of the H(sup (minus)) linac from 201 to 401.5 MeV. This is achieved by replacing the last four 201.24 MHz drift-tube linac cavities with seven 804.96 MHz side-coupled cavity modules. Each accelerator mod...
The muon spectrometer for the D0 experiment at Fermi National Accelerator Laboratory uses proportional drift tubes filled with an Ar-CO(sub 2)-CF(sub 4) gas mixture. Measurements of drift velocity as a function of electric field magnitude for 90%-5%-5% an...
Fermi National Accelerator Laboratory (Fermilab) D(null) collider, E-740, uses 150 proportional drift tube (P.D.T.) modules connected to a common multiple header to supply clean low pressure gas. A second multiple header returns the gas to the mixing area...
to match the beam to the de�tuned tank. The buncher following this tank is then used to capture placed between IH tanks provide pe� riodic transverse and longitudinal focussing respectively. Beam simulations show that the DTL can accelerate beams with little or no emittance growth over the complete energy
The post-acceleration of laser-generated protons through conventional drift tube linear accelerators has been simulated with the particle code Parmela. The proton source is generated on the rear surface of a target irradiated by an high-intensity (10{sup 19} W{center_dot}cm{sup -2}) short-pulse (350 fs) laser and ...
The high-energy part of a proton linac, following a drift tube section, accelerates protons and H/sup -/ ions of energies above 150 MeV. High efficiency and high gradients in the accelerating structure considered for this part of a proton linac are studied. Several known and improved structures working at 1350 MHz ...
The acceleration of large numbers of ions to high energies uses an intense relativistic electron beam produced by a vacuum diode. An electron beam radial profile is maintained by a strong longitudinal magnetic field. A virtual cathode, characterized by an electrostatic potential depression whose depth corresponds to the injected electron beam kinetic energy will form. The ...
The goal of the present research work is to develop a bonding method to produce quality ceramic-to-metal joints suitable for long term implantable biomedical devices, such as BIONRTM microstimulator where ceramic provides a transparent window for AC magnetic. A series of zirconia (3Y-TZP) ceramic to Ti-6Al-4V alloy braze runs have been carried out in vacuum using Tini-50RTM (50 wt.% Titanium/50 ...
The history of linear collective ion acceleration experiments is briefly reviewed, and several configurations in which collective ion acceleration has been observed are described. The experiments discussed include studies of small-scale vacuum breakdown, low-voltage plasma-triggered gaps, large-scale diode effects, ion acceleration by ...
This paper reports low-power tuning and stabilization measurements on the Los Alamos Ramped-Gradient Drift-Tube Linac (RGDTL). The RGDTL is a 425-MHz, 1.87-m-long structure containing 29 drift tubes, 14 post couplers, 2 tuners, and 2 drive loops. The design calls for an axial electric field gradient that increases from 2.0 MV/m to 4.4 ...
The space charge effect inside the beam of charged particles causes serious problems in high-intensity linear particle accelerators. At the present time there is only the Alvarez-Blewett accelerating structure which uses continuous strong focusing to keep the beam confined to the axis. The most serious problem is at the injection end of the ...
The Spallation Neutron Source (SNS) is a facility being designed for scientific and industrial research and development. SNS will generate and use neutrons as a diagnostic tool for medical purposes, material science, etc. The neutrons will be produced by bombarding a heavy metal target with a high-energy beam of protons, generated and accelerated with a linear particle ...
In this work we present details of the design and manufacture of a new alternating phase focus-interdigital H (APF-IH) drift tube (DT) linac. Using this apparatus we were able to successfully accelerate He+ ions from 80 up to 193.6 keV. The linac design employs an advanced power-efficiency configuration, APF-IH structure, which has ...
The Intertank Matching Section (IMS) of the Ground Test Accelerator (GTA) is a short (36 cm) beamline designed to match the Radio Frequency Quadrupole (RFQ) exit beam into the first Drift Tube LINAC (DTL) tank. The IMS contains two steering quadrupoles (SMQs) and four variable-field focussing quads (VFQs). The SMQs are fixed strength ...
The Hot Model for the Coupled Cavity Drift Tube Linac (CCDTL) resonance control cooling system (RCCS) for the Low Energy Demonstration Accelerator (LEDA) [1] in support of the Accelerator Production of Tritium (APT) [2] is described. Two hydraulic control loops are described that control the frequency in the CCDTL ...
A conference was held for discussing the design of linear accelerators suitable for use as injectors for high-energy machines. Drift-tube shaping and linac phase oscillations were treated in some detail. It is concluded that a 2- to 1O-Bev linac delivering approximately 20-ma protons cam be designed from the available information for a 300- to ...
The accelerator for the Accelerator based Production of Tritium (APT), uses a radio-frequency quadrupole (RFQ), followed by the newly developed coupled-cavity drift tube linac (CCDTL) and a coupled- cavity linac (CCL). The production target requires the APT linac to deliver a 100 mA proton beam with an energy of ...
According to some theories of gravity, antimatter will fall faster than matter in the earth's gravitational field. An experiment to measure the gravitational force on the antiproton is under construction. Antiprotons of a few MeV from the LEAR facility of CERN will be slowed down and caught in a large Penning electromagnetic trap. They will then be cooled and transferred to Penning ...
An intense relativistic electron beam cannot propagate in a metal drift tube when the current exceeds the space charge limit. Very high charge density and electric field gradients (10/sup 2/ to 10/sup 3/ MV/m) develop at the beam front and the electrons are reflected. When a neutral gas or a plasma is present, collective acceleration ...
IPCR heavy ion linac is of a Wideroe type, and its accelerating frequency is variable between 20 and 40 MHz. It is designed to accelerate ions with mass to charge ratios between 5 and 20 at these frequencies. Total voltage gain with six cavities is about 16 MV, the length of each cavity being three meters. Non-constancy of voltage between ...
Using the PARMILA code running under PC-WINDOWS, the present performance of the Fermilab Drift Tube Linac has been analyzed in the light of new demands on the Linac/Booster complex (the Proton Source). The Fermilab Drift Tube Linac (DTL) was designed in the sixties as a proton linac with a final energy of 200 MeV ...
... Title : The Permissibility of Lack-of-Brazing Defects in Brazed Joints in Tubular Systems of Power Plant Made of Steel 08Kh18N10T,. ...
Calculations of residual stresses in braze joints are required to validate designs for a variety of metal/ceramic joining applications. In particular, finite element analysis (FEA) codes have the capability of incorporating either elastic-plastic or minim...
Contents: Nickel; Average tensile properties of TD-6 brazed joints in td nickel-chromium after high-temperature exposure; Average tensile properties of td-6 brazed joints in td nickel-chromium; Aluminum; Refractory metals.
A method is described which allows the evaluation of the mechanical strength of a brazed joint by measuring the surface voltage when a current runs through the joint. The results are discussed and compared with those obtained from traditionnal destructive...
94-01 04.08 3200 High Thermal Conductance Brazed Joints for Hypersonic Vehicles and Bio-Medical X-Ray Targets. Abstract: Foster-Miller will demonstrate use ...
This paper presents results of the second part of an on-going effort to gain better understanding of defect tolerance in braze joints. In the first part of this three-part series, we mechanically tested and modeled the strength of the lap joints as a func...
Furnace brazing is a joining process used in the aerospace and other industries to produce strong permanent and hermetic structural joints. As in any joining process, brazed joints have various imperfections and defects. At the present time, our understan...
face sheet and foam core and shear failure of the brazed joints. .... The assumption of well-bonded brazed joints resistant to failure leaves only two failure modes ...
Methods of conducting stress analyses in metal-ceramic braze joints involving Kovar and alumina compositions are described. A schematic illustration of a braze configuration is included. The composition range for the glassy phase of the alumina system is ...
MS&T 2008 Pittsburgh, Joining Symposium. Active Metal Brazing and Characterization of Brazed Joints in C-C and C-SiC Composites to Copper-Clad- Molybdenum ...
The Coupled-Cavity Drift Tube Linac (CCDTL) is a relatively new RF accelerator structure which plays a major role in the APT Low-Energy Linac (LEL) design. Engineering development is pushing ahead on several fronts, including thermal management, fabrication procedures, cavity and coupling slot tuning, high-power prototype fabrication ...
The injection of laser-generated protons through conventional drift tube linear accelerators (linacs) has been studied numerically. For this, we used the parameters of the proton source produced by ultraintense lasers, i.e., with an intrinsic high beam quality. The numerical particle tracing code PARMELA[L. M. Young and J. H. Billen, ...
There are several refurbishment projects underway at the Los Alamos National Laboratory LANSCE linear accelerator. Systems involved are: RF, water cooling, networks, diagnostics, timing, controls, etc. The Drift Tube Linac (DTL) portion of the accelerator consists of four DTL tanks, each with three independent ...
... Accession Number : AD0192246. Title : ULTRASONIC INSPECTION CHECKS QUALITY OF BRAZED JOINTS. Corporate Author : ...
... Title : Towards and Understanding of the Reaction Sequences in Brazed Joints: Investigation of the Ti-Cu-O Ternary at 945 Degrees C. ...
... Title : Towards an Understanding of the Reaction Sequences in Brazed Joints: Investigation of the Ti-Cu-O Ternary at 945 Degrees C. ...
... Accession Number : ADD137830. Title : The Influence of Brazing Conditions on the Impact Strength of High-Temperature Brazed Joints,. ...
... Accession Number : ADD118642. Title : Selection of the Temperature for the Diffusion Annealing of Brazed Joints in Titanium Alloy VT6S,. ...
... Abstract : Tests were conducted to evaluate the shear strength of brazed joints with thin sheets of base metal, and to determine the shear strength ...
... technique might find numerous applications in nondestructive evaluation of different bonds of layered structures such as adhesive and brazed joints ...
... Accession Number : AD0178409. Title : NEW METHOD FOR EVALUATING STRENGTH AND DUCTILITY OF BRAZED JOINTS. Corporate Author : ...
... Descriptors : *Patent applications, *Ceramic materials, *Substrates, *Metallizing, Beryllium oxides, Brazing, Brazed joints, Metal joints, Chemical ...
... Descriptors : *BRAZED JOINTS, ENGINE COMPONENTS, HIGH TEMPERATURE, CONNECTORS, BRAZING, INDUCTION HEATING. ...
... Title : INFLUENCE OF PROCESS VARIABLES ON THE QUALITY OF DIFFUSION-BRAZED JOINTS BETWEEN STAINLESS STEEL AND BRONZE ...
Interaction equations were proposed earlier to predict failure in Albemet 162 brazed joints. Present
NASA Technical Reports Server (NTRS)
Tensile tests performed on AISI 316 stainless steel wide-gap brazed with nickel-based filler metal showed that the strength and elongation of the brazed joints increased with brazing temperature. The addition of the gap filler was able to improve the load-carrying capacity of the brazed joints only when the brazing ...
... Accession Number : ADD125945. Title : Effect of Heating Time at High Temperatures on the Structure and Properties of Brazed Joints,. ...
... Descriptors : *ALUMINUM ALLOYS, *BRAZING, *BRAZED JOINTS, MAGNESIUM, TENSILE PROPERTIES, BENDING, ZINC, FOILS(MATERIALS ...
... Accession Number : ADD137314. Title : Development of a Test for Determining Fracture Toughness of Brazed Joints in Ceramic Materials,. ...
... Accession Number : ADD101952. Title : CRACKING SUSCEPTIBILITY AND MICROSTRUCTURE OF NI-CR20-TI-AL BRAZED JOINTS,. ...
... Accession Number : ADD138658. Title : Adaptation of the DCB Test for Determining Fracture Toughness of Brazed Joints in Ceramic Materials,. ...
RADIOGRAPHIC INSPECTION OF INDUCTION BRAZED JOINTS IS VERIFIED. TESTING. ATP IS VERIFIED BY INSPECTION. HANDLING/PACKAGING ...
