The production of aluminum can produce large dynamic stray currents in the earth surrounding the production plant. When coated pipelines that are not grounded pass through the dynamic stray current area, they can realize failures at accelerated rates, even with traditional cathodic protection systems in operation. ...

A time-of-flight mass spectrometer is designed with means for eliminating stray ions. In the mass spectrometer, ionized particles are accelerated at right angles to their initial velocity and collected at a point in the path of the resultant velocity. (D.L.C.)

Beam interaction with background gas and walls produces ubiquitous clouds of stray electrons that frequently limit the performance of particle accelerator and storage rings. Counterintuitively we obtained the electron cloud accumulation by measuring the e...

Superconducting accelerator magnets usually have magnetic iron yokes to obtain maximum magnetic field and to limit stray field. However, the iron is expensive and heavy. The smaller size and weight of an iron-free magnet can result in lower magnet and refrigeration costs. However in a colliding beam accelerator the ...

Stray radiation measurements made at 23 particle accelerator sites are summarized and discussed. Conclusions with regard to safe accelerator operation are drawn, as well as general conclusions regarding radiation dosimetry, maximum permissible levels, and instrumentation. (auth)

Propeller shafts of AISI type 316 stainless steel (UNS S31600) on server ships suffered severe pitting within 12 days of launching. The corrosion occurred within the water-lubricated stern tubes in a pattern that outlined the bearing staves and the shaft packing seals. This suggested some form of crevice corrosion was involved. Rapid onset of pitting indicated the corrosion process was ...

STRAY-ELECTRON ACCUMULATION AND EFFECTS IN HIF ACCELERATORS R.H. Cohen1,2,* , A. Friedman1,2 , M National Laboratory, Berkeley, CA 94720 4 TechX Corp., Boulder, CO Abstract Stray electrons can- electron emission. Electron accumulation is impacted by the ion beam potential, accelerating fields

The restricted dose mean linear energy transfer (LET) (L500,D) of the stray radiation field a few centimeters outside the treatment volume has been measured for 12 and 18 MV photons produced by a clinical Therac-20 (AECL) accelerator. The measurements were performed as a function of field size and distance from the edge of the ...

The dosimetry of stray radiation fields around pulsed accelerators is complicated by the fact that the radiation comes in pulses and by the mixed nature of the radiation usually produced by these accelerators. Suitable instrumentation for pulsed radiation consists of special uses of standard ratemeters and ...

... These four designs are produced on a single microchip that includes the two phase non- overlapping clock circuit and the switches. ...

... These four designs are produced on a single microchip that includes the two phase nonoverlapping clock circuit and the switches. ...

One of the major problems in Thomson scattering measurement of electron temperature is the suppression of stray light. Filters of AR-coated ruby with a high percentage doping of Cr have been produced for use on SCATPAK II. The filters have negligible atte...

The proposed superconducting linear accelerator that accelerates muons from 190 MeV to 2.45 GeV will use superconducting solenoids for focusing the muon beam. The accelerator will use superconducting RF cavities. These cavities are very sensitive to stay magnetic field from the focusing magnets. Superconducting solenoids can have large ...

Radiation survey work at the Berkeley Bevatron has been a continuous project of the Health Physics Group since start-up of the accelerator in November 1954. A substantial body of survey data has accummulated, from which a general pattern for the stray radiation field can be constructed. This report includes a summary of the characteristics of the ...

voltages, a uctuation in the stray voltage imbalance #1; x , along the LISA sensitive axis, mixes is ongoing to better understand the origin of these stray DC voltages and their uctuations, as well stray DC voltage, a possible cause of the measured residual sti#11;ness, would produce a translational sti

Effects of stray electrons are a main factor limiting performance of many accelerators. Because heavy-ion fusion (HIF) accelerators will operate in regimes of higher current and with walls much closer to the beam than accelerators operating today, stray electrons might have a large, detrimental ...

Everyday features of the accelerator environment include long cable runs, high power and low level equipment sharing building space, stray electromagnetic fields and ground voltage differences between the sending and receiving ends of an installation. Thi...

Superconducting accelerator magnets usually have magnetic iron yokes to obtain maximum magnetic field and to limit stray field. However, the iron is expensive and heavy. The smaller size and weight of an iron-free magnet can result in lower magnet and ref...

Obtaining the magnetic properties of non-resolved structures in the solar photosphere is always challenging and problems arise because the inversion is carried out through the numerical minimization of a merit function that depends on the proposed model. We investigate the reliability of inversions in which the stray-light contamination is obtained from the same observations ...

The interference of stray electrons (also called �electron clouds�) with accelerator beams is important in modern intense-beam accelerators, especially those with beams of positive charge. In magnetic wigglers, used, for instance, for transverse emittance damping, the intense synchrotron radiation produced by ...

Stray electrons can be introduced in positive-charge accelerators for heavy ion fusion (or other applications) as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary-electron emission. Electron accumulation is impacted by the ion beam potential, accelerating fields, ...

... 44 2. Stray X-rays ..... ... made to the system configuration was to attenuate the relatively high voltage signals (diode and Marx voltages) at ...

The printed circuit board provided a convenient way of minimizing circuit loops, which could otherwise produce stray voltages and fields. The leads were con- ...

Jan 22, 2011 ... Hybrid systems execute plans where each action is implemented to robustly produce effects if the world does not stray outside the action's ...

A 4 MV peak voltage pulser for the Troll accelerator has been designed, fabricated, and delivered to Sandia National Laboratories by Maxwell Laboratories, Inc. The pulser is required to produce a flat-top pulse, with a variable width, to drive a cold-cathode diode. The system operates over a range of 2 to 4 MV. A 46-stage Marx generator is used to directly ...

The pitting corrosion of more than 50 casing samples from eight manufacturers (nine mills) was evaluated using the stray current accelerated test (SCAT) procedure. The quality of mill scale on tubulars casing, tubing, rods, and drill pipe is a major factor affecting pitting rates and tubular life. The data indicates SCAT can help identify areas where ...

An array of independently connected photovoltaic cells on a semi-insulating substrate contains reflective coatings between the cells to enhance efficiency. A uniform, flat top laser beam profile is illuminated upon the array to produce electrical current having high voltage. An essentially wireless system includes a laser energy source being fed through optic fiber and cast ...

Beam interaction with background gas and walls produces ubiquitous clouds of stray electrons that frequently limit the performance of particle accelerator and storage rings. Counterintuitively we obtained the electron cloud accumulation by measuring the expelled ions that are originated from the beam-background gas interaction, rather ...

A test procedure is described that has been used to determine if casing (tubulars) from various mills will corrode in a general or pitting-type pattern. The equipment required to run the test is relatively inexpensive and gives meaningful results in one to two weeks. The Stray Current Accelerated Test (SCAT) accelerates the corrosion ...

frequencies by the stray acceleration noise in the orbits of the nominally free-falling test masses that serve#12;guration and is not present in LISA. Limiting this noise source requires both high actuation voltage stray force sources with LTP Several key random force noise sources are plotted in Fig. 2 for LTP

The design of a focusing solenoid for use in a superconducting RF linac requires resolving a range of problems with conflicting requirements. Providing the required focusing strength contradicts the goal of minimizing the stray field on the surfaces of ad...

The dosimetry of small fields as used in stereotactic radiotherapy, radiosurgery and intensity-modulated radiation therapy can be challenging and inaccurate due to partial volume averaging effects and possible disruption of charged particle equilibrium. Consequently, there exists a need for an integrating, tissue equivalent dosimeter with high spatial resolution to avoid perturbing the radiation ...

The dosimetry of small fields as used in stereotactic radiotherapy, radiosurgery and intensity-modulated radiation therapy can be challenging and inaccurate due to partial volume averaging effects and possible disruption of charged particle equilibrium. Consequently, there exists a need for an integrating, tissue equivalent dosimeter with high spatial resolution to avoid perturbing the radiation ...

Stray electrons can arise in positive-ion accelerators for heavy ion fusion or other applications as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary- electron emission. We summarize results from several studies undertaken in conjunction with an effort to develop a self-consistent modeling ...

The injection onto the first cyclotron orbit differs essentially from injection schemes for normal conducting sector cyclotrons because of two reasons: the central region is occupied by the RF-cavities, and the stray field between the sectors is strongly nonscaling with the mean field level. An appropriate injection and extraction system was developed using a series of ...

Straying results in an exchange of individuals between wild and hatchery salmon populations and is important because it could affect their genetic differences. Understanding what factors affect straying could help in the development of procedures for controlling the influence of specific stocks on nearby populations. We explore the effects of release date ...

Stray electrons can be introduced in heavy ion fusion accelerators as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary-electron emission. We summarize here results from several studies of electron-cloud accumulation and effects: (1) Calculation of the electron cloud ...

... Development of a linear accelerator for production of a bunched ... This accelerator was ... Calibration of an analyzing magnet intended to produce, by ...

Samples of soil, water, aluminum, copper and iron were irradiated in the stray radiation field generated by the interaction of a 28.5 GeV electron beam in a copper-dump in the Beam Dump East facility at SLAC. The specific activity induced in the samples was measured by gamma spectroscopy and other techniques. In addition, the isotope production in the samples was calculated ...

Page 1. Accelerated Insertion of Materials � Manufacturing and Producibility of Hat Stiffened Structure ... AIM-C Producibility Heuristics ...

Stray electrons can be introduced in positive-charge accelerators for heavy ion fusion (or other applications) as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary-electron emission. Electron accumulation is impacted by the ion beam potential, accelerating fields, ...

Stray electrons can arise in positive-ion accelerators for heavy ion fusion or other applications as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary- electron emission. We summarize resu...

Induction linear accelerators (LIAs) are inherently capable of accelerating several thousand amperes of /approximately/ 50-ns duration pulses to > 100 MeV. In this paper we report progress and status in the areas of duty factor and stray power management. These technologies are vital if LIAs are to attain high average power ...

Everyday features of the accelerator environment include long cable runs, high power and low level equipment sharing building space, stray electromagnetic fields and ground voltage differences between the sending and receiving ends of an installation. This paper pictures some Fermilab installations chosen to highlight significant features and presents ...

Everyday features of the accelerator environment include long cable runs, high power and low level equipment sharing building space, stray electromagnetic fields and ground voltage differences between the sending and receiving ends of an installation. This paper pictures some Fermilab installations chosen to highlight significant features and presents ...

Samples of materials which will be used in the LHC machine for shielding and construction components were irradiated in the stray radiation field of the CERN-EU high-energy reference field facility. After irradiation, the specific activities induced in th...

Stray electrons can be introduced in positive-charge accelerators for heavy ion fusion (or other applications) as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary-electron emission. We are developing a capability for self-consistent simulation of ion beams with the electron clouds they ...

Superconducting radio frequency (SRF) cavities are a popular choice among researchers designing new accelerators because of the reduced power losses due to surface resistance. However, SRF cavities still have unresolved problems, including the loss of power to stray electrons. Sources of these electrons are field emission from the walls and ionization of ...

The Fermilab accelerator is comprised of four major systems: the high-energy beam-extraction and switching system, the main accelerator (main ring), the booster, and the linear accelerator. The Fermilab accelerator produces accelerated beams for a vigorou...

We have proposed measuring the acceleration of antiprotons in the Earth`s gravitational field by launching antiprotons from a thermal distribution at 4 K upwards against the force of gravity and measuring their time-of-flight (TOF). The TOF distribution thus obtained will exhibit a cut-off representing the minimum kinetic energy necessary to reach the detector at the top of ...

We have proposed measuring the acceleration of antiprotons in the Earth's gravitational field by launching antiprotons from a thermal distribution at 4 K upwards against the force of gravity and measuring their time-of-flight (TOF). The TOF distribution thus obtained will exhibit a cut-off representing the minimum kinetic energy necessary to reach the detector at the top of ...

The probability distribution P(zeta) of diffusive and advective molecular displacements is determined using a fixed field gradient (FFG) pulse sequence, on fluid flow through a Bentheimer sandstone, in the grossly inhomogeneous stray field of a super-conducting magnet. Two decades of q-space are scanned with stimulated echoes, using the gradient of the ...

The probability distribution P (?) of diffusive and advective molecular displacements is determined using a fixed field gradient (FFG) pulse sequence, on fluid flow through a Bentheimer sandstone, in the grossly inhomogeneous stray field of a super-conducting magnet. Two decades of q-space are scanned with stimulated echoes, using the gradient of the stray ...

The Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua platform has nine spectral bands with center wavelengths from 412 to 870 nm that are used to produce the standard ocean color data products. Ocean scenes usually contain high contrast due to the presence of bright clouds over dark water. About half of the MODIS Aqua ocean pixels are flagged as spatial ...

One of the major problems in Thomson scattering measurement of electron temperature is the suppression of stray light. Filters of AR-coated ruby with a high percentage doping of Cr have been produced for use on SCATPAK II. The filters have negligible attenuation of the signal above 7000 A/sup 0/ and attenuate light at the laser line by a factor of eta9. ...

One of the major problems in Thomson scattering measurement of electron temperature is the suppression of stray light. Filters of AR-coated ruby with a high-percentage doping of Cr have been produced for use on SCATPAK II. The filters have negligible attenuation of the signal above 7000 A-circle and attenuate light at the laser line by a factor of approx. ...

We have developed a thermal-neutron coded-aperture imager that reveals the locations of hydrogenous materials from which thermal neutrons are being emitted. This imaging detector can be combined with an accelerator to form an active interrogation system in which fast neutrons are produced in a heavy metal target by means of xcitation by high energy ...

We have developed a thermal-neutron coded-aperture imager that reveals the locations of hydrogenous materials from which thermal neutrons are being emitted. This imaging detector can be combined with an accelerator to form an active interrogation system in which fast neutrons are produced in a heavy metal target by means of excitation by high energy ...

This paper discusses the acceleration of charged particles by electromagnetic fields, i.e., by fields that are produced by the motion of other charged particles driven by some power source. The mechanisms that are discussed include: Ponderamotive Forces, Acceleration, Plasma Beat Wave Acceleration, Inverse Free ...

The history of linear accelerators is outiined, and the characteristics of linear accelerators used to achieve high energies are described. Electron accelerators are discussed, and the use of the Cockcroft-Walton accelerator to produce neutrons by the D-T reaction is shown. (T.F.H.)

... as on the thickness and atomic species ... shot accelerators that produce beams of accelerated ... stabilization us- ing controllable deceleration voltage. ...

Accelerated sodium pyruvate decomposition in aqueous solution due to proteinoids produced by thermal

Stray electrons can be introduced in heavy ion fusion accelerators as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary- electron emission. We summarize here results from several studies o...

Stray electrons can be introduced in positive-charge accelerators for heavy ion fusion (or other applications) as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary-electron emission. We ar...

A number of test measurements were made on the B-1 Stellarator. Measurements were current in the confining field windings, the confining field in a straight section as a function of axial position tor various areas of aperture, and the stray fields inside the plasma aperture region due to the accelerating field. Measurements are described and ...

A collaboration involving the Biomedical Research Foundation, Science Applications International Corporation, Fermi National Accelerator Laboratory, and the University of Washington is developing an accelerator for producing isotopes for Positron Emission...

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 ...

... diagnostics have been developed for measuring laser produced plasma ... Keywords: Hypervelocity acceleration; Rail gun; Kinetic energy weapon. ...

Effect of Stable Phase Formation from Unstable Phase on Densification Acceleration of Amorphous Powder Produced by Mechanical Alloying

Low energy electron accelerator to produce measurably small fluxes through photoelectric effect from

We propose an Explorer Mission of Opportunity program to develop and operate a large-aperture ultraviolet coronagraph spectrometer called the Coronal Physics Investigator (CPI) as an attached International Space Station (ISS) payload. The primary goal of this program is to identify and characterize the physical processes that heat and accelerate the primary and secondary ...

Stray electrons can arise in positive-ion accelerators for heavy ion fusion or other applications as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary- electron emission. We summarize the distinguishing features of electron cloud issues in heavy-ion-fusion accelerators ...

The DIII-D Thomson scattering system has been expanded to measure divertor plasma temperatures from 1-500 eV and densities from 0.05 to 8 X 10{sup 20} m{sup -3}. To complete this system, a difficult stray light problem was overcome to allow for an accurate Rayleigh scattering density calibration. The initial stray light levels were over 500 times higher ...

Proton beam radiotherapy unavoidably exposes healthy tissue to stray radiation emanating from the treatment unit and secondary radiation produced within the patient. These exposures provide no known benefit and may increase a patient's risk of developing a radiogenic cancer. The aims of this study were to calculate doses to major organs and tissues and to ...

Radiochromic plastic and gel materials have recently emerged which can yield 3D dose information over clinical volumes in high resolution. These dosimeters can provide a much more comprehensive verification of complex radiation therapy treatments than can be achieved by conventional planar and point dosimeters. To achieve full clinical potential, these dosimeters require a fast and accurate ...

Radiochromic plastic and gel materials have recently emerged which can yield 3D dose information over clinical volumes in high resolution. These dosimeters can provide a much more comprehensive verification of complex radiation therapy treatments than can be achieved by conventional planar and point dosimeters. To achieve full clinical potential, these dosimeters require a fast and accurate ...

An electromagnetic accelerator is designed for accelerating an ionized gas plasma to extremely high velocities at high flow rates. In the accelerator, a moving, preferably accelerating, magnetic field accelerates a ring-shaped plasma mass from one end of a structure to the other end to ...

The Advanced Solar Coronal Explorer (ASCE) is a mid-explorer (MidEx) mission selected, together with other five, for the a Phase A Concept Study in the 1999 round of MidEX proposal. ASCE's spacecraft bus is a SPARTAN 400 reusable carrier deployed in low Earth orbit by the Space Shuttle. ASCE's payload comprises two instrument modules, the Spectroscopic and Polarimetric Coronagraph (SPC) and the ...

Recently attention has focused on charged particle acceleration in a plasma by a fast, large amplitude, longitudinal electron plasma wave. The plasma beat wave and plasma wakefield accelerators are two efficient ways of producing ultra-high accelerating g...

Recently, producing and maintaining short bunches in accelerators has become a forefront issue. Examples of accelerators that require short bunches are high quality nuclear physics accelerators, free electron laser driver accelerators, next generation lin...

An automatic frequency control system is described for maintaining the drive frequency applied to a linear accelerator to produce maximum particle output from the accelerator. The particle output amplitude is measured and the frequency of the radio frequency source powering the linear accelerator is adjusted to ...

... a dangerous condition cannot occur; (3) decrease the response of the EED's to stray voltage; and (4) check the EED firing circuit for stray voltages. ...

This book is covered under the following topics: stray light concepts and theory; stray radiation in optical system; BRDF instrumentation; and BSDF data and tests.

The temperature rise produced by synchrotron radiation incident on the vacuum chamber wall of a betatron is evaluated for a general acceleration cycle.

... Insertion of Materials � Composites (AIM-C) Producibility Module Development ... Red = Basic Activity Producibility Module Software ...

... DOE produces both stable isotopes and radioisotopes. ... Radioisotopes are produced in nuclear reactors or particle accelerators. ...

Ion beams injected into the ionosphere are known to produce waves related to the normal modes of the

An accelerator-driven spallation neutron-source target/blanket system has been developed for the production of tritium. The system employs a proton linear accelerator, and a lead neutron-producing target, surrounded by tritium-producing blankets based on ...

In the first chapter, terminology, physical and radiological quantities, and units of measurement used to describe the properties of accelerator radiation fields are reviewed. The general considerations of primary radiation fields pertinent to accelerators are discussed. The primary radiation fields produced by electron beams are ...

Proton radiography using energetic protons from accelerator producing high contrast and poor spatial

... Title : BULK ELEMENTAL ANALYSIS BY THE INELASTIC SCATTERING OF NEUTRONS PRODUCED WITH A VAN DE GRAAFF ACCELERATOR. ...