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Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

RF and Beam Diagnostic Instrumentation at the Advanced Photon Source (APS) Linear Accelerator (Linac)  

E-Print Network (OSTI)

RF and Beam Diagnostic Instrumentation at the Advanced Photon Source (APS) Linear Accelerator (Linac)

Grelick, A E; Arnold, N; White, M

1996-01-01T23:59:59.000Z

2

EA-1904: Linac Coherent Light Source II at Stanford Linear Accelerator  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

04: Linac Coherent Light Source II at Stanford Linear 04: Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, California EA-1904: Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, California Summary This EA evaluates the environmental impacts of the proposed construction of the Linac Coherent Light Source at SLAC National Accelerator Laboratory, Menlo Park, California. Public Comment Opportunities None available at this time. For more information, contact: Mr. Dave Osugi DOE SLAC Site Office 2575 Sand Hill Road, MS8A Menlo Park, CA 94025 Electronic mail: dave.osugi@sso.science.doe.gov Documents Available for Download March 7, 2012 EA-1904: Finding of No Significant Impact Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, CA

3

EA-1904: Linac Coherent Light Source II at Stanford Linear Accelerator  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

4: Linac Coherent Light Source II at Stanford Linear 4: Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, California EA-1904: Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, California Summary This EA evaluates the environmental impacts of the proposed construction of the Linac Coherent Light Source at SLAC National Accelerator Laboratory, Menlo Park, California. Public Comment Opportunities None available at this time. For more information, contact: Mr. Dave Osugi DOE SLAC Site Office 2575 Sand Hill Road, MS8A Menlo Park, CA 94025 Electronic mail: dave.osugi@sso.science.doe.gov Documents Available for Download March 7, 2012 EA-1904: Finding of No Significant Impact Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, CA

4

Linear Accelerator | Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

electrons emitted from a cathode heated to 1100 C. The electrons are accelerated by high-voltage alternating electric fields in a linear accelerator (linac; photo below)....

5

LINEAR ACCELERATOR  

DOE Patents (OSTI)

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 tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.

Christofilos, N.C.; Polk, I.J.

1959-02-17T23:59:59.000Z

6

Finding of No Significant Impact for the Construction and Operation of the Linac Coherent Light Source (LCLS) at the Stanford Linear Accelerator Center (SLAC), California (DOE/EA-1426) (2/28/03)  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

U.S. Department of Energy (DOE) U.S. Department of Energy (DOE) Finding of No Significant Impact Construction and Operation of the Linac Coherent Light Source (LCLS) at the Stanford Linear Accelerator Center (SLAC), California. AGENCY: U.S. Department of Energy (DOE) ACTION: Finding of No Significant Impact (FONSI) SUMMARY: The U.S. Department of Energy (DOE) has prepared an Environmental Assessment (EA), DOE/EA-1426, evaluating the proposed action to construct and operate the Linac Coherent Light Source (LCLS) at the Stanford Linear Accelerator Center (SLAC). Based upon the information and analyses in the EA, the DOE has determined that the proposed federal action does not significantly affect the quality of the human environment within the meaning of the National Environmental Policy Act of 1969.

7

Focusing in Linear Accelerators  

DOE R&D Accomplishments (OSTI)

Review of the theory of focusing in linear accelerators with comments on the incompatibility of phase stability and first-order focusing in a simple accelerator.

McMillan, E. M.

1950-08-24T23:59:59.000Z

8

North Linear Accelerator  

NLE Websites -- All DOE Office Websites (Extended Search)

North Linear Accelerator North Linear Accelerator Building Exterior Beam Enclosure Level Walk to the North Spreader North Recombiner Extras! North Linear Accelerator The North Linear Accelerator is one of the two long, straight sections of Jefferson Lab's accelerator. Electrons gain energy in this section by passing through acceleration cavities. There are 160 cavities in this straightaway, all lined up end to end. That's enough cavities to increase an electron's energy by 400 million volts each time it passes through this section. Electrons can pass though this section as many as five times! The cavities are powered by microwaves that travel down the skinny rectangular pipes from the service buildings above ground. Since the cavities won't work right unless they are kept very cold, they

9

Testing and Implementation Progress on the Advanced Photon Source (APS) Linear Accelerator (Linac) High-Power S-band Switching System  

E-Print Network (OSTI)

An S-band linear accelerator is the source of particles and the front end of the Advanced Photon Source injector. In addition, it supports a low-energy undulator test line (LEUTL) and drives a free-electron laser (FEL). A waveguide-switching and distribution system is now under construction. The system configuration was revised to be consistent with the recent change to electron-only operation. There are now six modulator-klystron subsystems, two of which are being configured to act as hot spares for two S-band transmitters each, so that no single failure will prevent injector operation. The two subsystems are also used to support additional LEUTL capabilities and off-line testing. Design considerations for the waveguide-switching subsystem, topology selection, control and protection provisions, high-power test results, and current status are described

Grelick, A E; Berg, S; Dohan, D A; Goeppner, G A; Kang, Y W; Nassiri, A; Pasky, S; Pile, G; Smith, T; Stein, S J

2000-01-01T23:59:59.000Z

10

Portable Linear Accelerator Development  

Science Conference Proceedings (OSTI)

This report describes Minac-3, a miniaturized linear accelerator system. It covers the current equipment capabilities and achievable modifications, applications information for prospective users, and technical information on high-energy radiography that is useful for familiarization and planning. The design basis, development, and applications history of Minac are also summarized.

1982-12-01T23:59:59.000Z

11

HEAVY ION LINEAR ACCELERATOR  

DOE Patents (OSTI)

A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.

Van Atta, C.M.; Beringer, R.; Smith, L.

1959-01-01T23:59:59.000Z

12

Linear induction accelerator  

DOE Patents (OSTI)

A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

Buttram, M.T.; Ginn, J.W.

1988-06-21T23:59:59.000Z

13

History of Proton Linear Accelerators  

DOE R&D Accomplishments (OSTI)

Some personal recollections are presented that relate to the author`s experience developing linear accelerators, particularly for protons. (LEW)

Alvarez, L. W.

1987-01-00T23:59:59.000Z

14

Berkeley Proton Linear Accelerator  

DOE R&D Accomplishments (OSTI)

A linear accelerator, which increases the energy of protons from a 4 Mev Van de Graaff injector, to a final energy of 31.5 Mev, has been constructed. The accelerator consists of a cavity 40 feet long and 39 inches in diameter, excited at resonance in a longitudinal electric mode with a radio-frequency power of about 2.2 x 10{sup 6} watts peak at 202.5 mc. Acceleration is made possible by the introduction of 46 axial "drift tubes" into the cavity, which is designed such that the particles traverse the distance between the centers of successive tubes in one cycle of the r.f. power. The protons are longitudinally stable as in the synchrotron, and are stabilized transversely by the action of converging fields produced by focusing grids. The electrical cavity is constructed like an inverted airplane fuselage and is supported in a vacuum tank. Power is supplied by 9 high powered oscillators fed from a pulse generator of the artificial transmission line type.

Alvarez, L. W.; Bradner, H.; Franck, J.; Gordon, H.; Gow, J. D.; Marshall, L. C.; Oppenheimer, F. F.; Panofsky, W. K. H.; Richman, C.; Woodyard, J. R.

1953-10-13T23:59:59.000Z

15

Acceleration Modules in Linear Induction Accelerators  

E-Print Network (OSTI)

Linear Induction Accelerator (LIA) is a unique type of accelerator, which is capable to accelerate kiloAmpere charged particle current to tens of MeV energy. The present development of LIA in MHz busting mode and successful application into synchrotron broaden LIAs usage scope. Although transformer model is widely used to explain the acceleration mechanism of LIAs, it is not appropriate to consider the induction electric field as the field which accelerates charged particles for many modern LIAs. Authors examined the transition of the magnetic cores functions during LIA acceleration modules evolution, distinguished transformer type and transmission line type LIA acceleration modules, and reconsidered several related issues based on transmission line type LIA acceleration module. The clarified understanding should be helpful in the further development and design of the LIA acceleration modules.

Wang, Shaoheng

2013-01-01T23:59:59.000Z

16

RECENT PROGRESS TOWARD A MUON RECIRCULATING LINEAR ACCELERATOR  

SciTech Connect

Both Neutrino Factories (NF) and Muon Colliders (MC) require very rapid acceleration due to the short lifetime of muons. After a capture and bunching section, a linac raises the energy to about 900 MeV, and is followed by one or more Recirculating Linear Accelerators (RLA), possibly followed by a Rapid Cycling Synchnotron (RCS) or Fixed-Field Alternating Gradient (FFAG) ring. A RLA reuses the expensive RF linac section for a number of passes at the price of having to deal with different energies within the same linac. Various techniques including pulsed focusing quadruopoles, beta frequency beating, and multipass arcs have been investigated via simulations to improve the performance and reduce the cost of such RLAs.

Slawomir Bogacz, Vasiliy Morozov, Yves Roblin, Kevin Beard

2012-07-01T23:59:59.000Z

17

Cast dielectric composite linear accelerator  

DOE Patents (OSTI)

A linear accelerator having cast dielectric composite layers integrally formed with conductor electrodes in a solventless fabrication process, with the cast dielectric composite preferably having a nanoparticle filler in an organic polymer such as a thermosetting resin. By incorporating this cast dielectric composite the dielectric constant of critical insulating layers of the transmission lines of the accelerator are increased while simultaneously maintaining high dielectric strengths for the accelerator.

Sanders, David M. (Livermore, CA); Sampayan, Stephen (Manteca, CA); Slenes, Kirk (Albuquerque, NM); Stoller, H. M. (Albuquerque, NM)

2009-11-10T23:59:59.000Z

18

Annual Planning Summaries: Stanford Linear Accelerator (SLAC...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Stanford Linear Accelerator (SLAC) Annual Planning Summaries: Stanford Linear Accelerator (SLAC) Document(s) Available For Download January 11, 2012 2012 Annual Planning Summary...

19

Electron Linacs for High Energy Physics  

Science Conference Proceedings (OSTI)

The purpose of this article is to introduce some of the basic physical principles underlying the operation of electron linear accelerators (electron linacs). Electron linacs have applications ranging from linacs with an energy of a few MeV, such that the electrons are approximately relativistic, to future electron-positron linear colliders having a collision energy in the several-TeV energy range. For the most part, only the main accelerating linac is treated in this article.

Wilson, Perry B.; /SLAC

2011-11-08T23:59:59.000Z

20

Reliable-linac design for accelerator-driven subcritical reactor systems.  

Science Conference Proceedings (OSTI)

Accelerator reliability corresponding to a very low frequency of beam interrupts is an important new accelerator requirement for accelerator-driven subcritical reactor systems. In this paper we review typical accelerator-reliability requirements and discuss possible methods for meeting these goals with superconducting proton-linac technology.

Wangler, Thomas P.,

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Advanced test accelerator: a high-current induction linac  

SciTech Connect

The Advanced Test Accelerator (ATA) is a linear induction accelerator being built at Lawrence Livermore National Laboratory. The aim of the ATA, together with its associated physics program is the research and development necessary to resolve whether particle-beam propagation is possible. Since the accelerator is the tool needed to do the basic propagation experiment, many of its design parameters are specified by the physics. The accelerator parameters are: 50 MeV, 10 kA, 70 ns pulse width (FWHM), and a 1 kHz rep-rate during a ten-pulse burst. In addition, beam quality and pulse-to-pulse repeatability must be excellent. The unique features of the accelerator are the 10 kA beam and the 1 kHz burst frequency.

Cook, E.G.; Birx, D.L.; Reginato, L.L.

1982-11-01T23:59:59.000Z

22

SLAC National Accelerator Laboratory - Linac Coherent Light Source...  

NLE Websites -- All DOE Office Websites (Extended Search)

LCLS - Linac Coherent Light Source Banner image of LCLS undulator hall. LCLS, the world's first hard X-ray free-electron laser, pushes science to new extremes with ultrabright,...

23

Voltage regulation in linear induction accelerators  

DOE Patents (OSTI)

Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor when it is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.

Parsons, W.M.

1991-03-19T23:59:59.000Z

24

Voltage regulation in linear induction accelerators  

DOE Patents (OSTI)

Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.

Parsons, W.M.

1992-12-29T23:59:59.000Z

25

Transverse emittance dilution due to coupler kicks in linear accelerators  

E-Print Network (OSTI)

One of the main concerns in the design of low emittance linear accelerators (linacs) is the preservation of beam emittance. Here we discuss one possible source of emittance dilution due to transverse electromagnetic fields in the accelerating cavities of the linac caused by the power coupler geometry. It is common wisdom that emittance growth from coupler kicks can be strongly reduced by having the coupler location alternate from above to below the beam pipe so that the coupler kick from one cavity is compensated by that of the next. While this is correct, alternating the coupler location requires large technical changes in superconducting cryomodules where cryogenic pipes are arranged parallel to a string of several cavities. We show here that cavities with high external $Q$ have coupler kicks that change the sign of their phase when the coupler is moved from before to after the cavity, as long as one accelerates on crest. This implies that the emittance growth from one cavity can be canceled by the next, pr...

Buckley, Brandon

2007-01-01T23:59:59.000Z

26

Linear Fixed-Field Multi-Pass Arcs for Recirculating Linear Accelerators  

SciTech Connect

Recirculating Linear Accelerators (RLA's) provide a compact and efficient way of accelerating particle beams to medium and high energies by reusing the same linac for multiple passes. In the conventional scheme, after each pass, the different energy beams coming out of the linac are separated and directed into appropriate arcs for recirculation, with each pass requiring a separate fixed-energy arc. In this paper we present a concept of an RLA return arc based on linear combined-function magnets, in which two and potentially more consecutive passes with very different energies are transported through the same string of magnets. By adjusting the dipole and quadrupole components of the constituting linear combined-function magnets, the arc is designed to be achromatic and to have zero initial and final reference orbit offsets for all transported beam energies. We demonstrate the concept by developing a design for a droplet-shaped return arc for a dog-bone RLA capable of transporting two beam passes with momenta different by a factor of two. We present the results of tracking simulations of the two passes and lay out the path to end-to-end design and simulation of a complete dog-bone RLA.

V.S. Morozov, S.A. Bogacz, Y.R. Roblin, K.B. Beard

2012-06-01T23:59:59.000Z

27

Independent Oversight Inspection, Stanford Linear Accelerator Center -  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Stanford Linear Accelerator Stanford Linear Accelerator Center - January 2007 Independent Oversight Inspection, Stanford Linear Accelerator Center - January 2007 January 2007 Inspection of Environment, Safety, and Health Programs at the Stanford Linear Accelerator Center The U.S. Department of Energy (DOE) Office of Independent Oversight, within the Office of Health, Safety and Security, conducted an inspection of environment, safety, and health (ES&H) programs at the DOE Stanford Linear Accelerator Center (SLAC) during October and November 2006. The inspection was performed by Independent Oversight's Office of Environment, Safety and Health Evaluations. Since the 2004 Type A electrical accident, SSO and SLAC have made improvements in many aspects of ES&H programs. However, the deficiencies in

28

Ion effects in future circular and linear accelerators  

SciTech Connect

In this paper, the author discusses ion effects relevant to future storage rings and linear colliders. The author first reviews the conventional ion effects observed in present storage rings and then discusses how these effects will differ in the next generation of rings and linacs. These future accelerators operate in a new regime because of the high current long bunch trains and the very small transverse beam emittances. Usually, storage rings are designed with ion clearing gaps to prevent ion trapping between bunch trains or beam revolutions. Regardless, ions generated within a single bunch train can have significant effects. The same is true in transport lines and linacs, where typical vacuum pressures are relatively high. Amongst other effects, the author addresses the tune spreads due to the ions and the resulting filamentation which can severely limit emittance correction techniques in future linear colliders, the bunch-to-bunch coupling due to the ions which can cause a multi-bunch instability with fast growth rates, and the betatron coupling and beam halo creation which limit the vertical emittance and beam lifetimes.

Raubenheimer, T.O.

1995-05-01T23:59:59.000Z

29

Transverse Beam Emittance Measurements of a 16 MeV Linac at the Idaho Accelerator Center  

SciTech Connect

A beam emittance measurement of the 16 MeV S-band High Repetition Rate Linac (HRRL) was performed at Idaho State University's Idaho Accelerator Center (IAC). The HRRL linac structure was upgraded beyond the capabilities of a typical medical linac so it can achieve a repetition rate of 1 kHz. Measurements of the HRRL transverse beam emittance are underway that will be used to optimize the production of positrons using HRRL's intense electron beam on a tungsten converter. In this paper, we describe a beam imaging system using on an OTR screen and a digital CCD camera, a MATLAB tool to extract beamsize and emittance, detailed measurement procedures, and the measured transverse emittances for an arbitrary beam energy of 15 MeV.

S. Setiniyaz, T.A. Forest, K. Chouffani, Y. Kim, A. Freyberger

2012-07-01T23:59:59.000Z

30

2011 Annual Planning Summary for Stanford Linear Accelerator...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Stanford Linear Accelerator Center Site Office (SLAC) 2011 Annual Planning Summary for Stanford Linear Accelerator Center Site Office (SLAC) The ongoing and projected Environmental...

31

Upgrade of the Drive LINAC for the AWA Facility Dielectric Two-Beam Accelerator  

SciTech Connect

We report on the design of a seven-cell, standing-wave, 1.3-GHz rf cavity and the associated beam dynamics studies for the upgrade of the drive beamline LINAC at the Argonne Wakefield Accelerator (AWA) facility. The LINAC design is a compromise between single-bunch operation (100 nC {at} 75 MeV) and minimization of the energy droop along the bunch train during bunch-train operation. The 1.3-GHz drive bunch-train target parameters are 75 MeV, 10-20-ns macropulse duration, and 16 x 60 nC microbunches; this is equivalent to a macropulse current and beam power of 80 A and 6 GW, respectively. Each LINAC structure accelerates approximately 1000 nC in 10 ns by a voltage of 11 MV at an rf power of 10 MW. Due to the short bunch-train duration desired ({approx}10 ns) and the existing frequency (1.3 GHz), compensation of the energy droop along the bunch train is difficult to accomplish by means of the two standard techniques: time-domain or frequency-domain beam loading compensation. Therefore, to minimize the energy droop, our design is based on a large stored energy rf cavity. In this paper, we present our rf cavity optimization method, detailed rf cavity design, and beam dynamics studies of the drive beamline.

Power, John; /Argonne; Conde, Manoel; /Argonne; Gai, Wei; /Argonne; Li, Zenghai; /SLAC; Mihalcea, Daniel; /Northern Illinois U.

2012-07-02T23:59:59.000Z

32

Status of the Linac Coherent Light Source  

Science Conference Proceedings (OSTI)

The Linac Coherent Light Source (LCLS) is a free electron laser facility in construction at Stanford Linear Accelerator Center. It is designed to operate in the wavelength range 0.15-1.5 nanometers. At the time of this conference, civil construction of new tunnels and buildings is complete, the necessary modifications to the SLAC linac are complete, and the undulator system and x-ray optics/diagnostics are being installed. The electron gun, 135 MeV injector linac and 250 MeV bunch compressor were commissioned in 2007. Accelerator commissioning activities are presently devoted to the achievement of performance goals for the completed 14 GeV linac.

Galayda, John N.; /SLAC

2011-11-04T23:59:59.000Z

33

Measurements of H/sup 0/ and H/sup +/ ion yields during H/sup -/ acceleration in a 50-MeV linac  

DOE Green Energy (OSTI)

Unlike proton linacs where the only particles that can be transported are protons, an H/sup -/ linac can produce H/sup 0/ and protons by stripping off one or both electrons of H/sup -/ ions during acceleration. We have measured yields of these ions as a function of linac tank pressures.

Cho, Y.; Madsen, J.; Shin, S.A.; Stipp, V.

1981-01-01T23:59:59.000Z

34

Low energy improvements to the Fermilab 400-MeV linear accelerator  

SciTech Connect

Improvements in the Fermilab operating 400-MeV linear accelerator injector are required to achieve the beam intensity and emittance requirement of the Proton Driver design study [5]. It has been determined that these requirements can be achieved by replacing the components in the Linac below 10 MeV. An improved H{sup {minus}} ion source with an electrostatic transport to a two-section Radio-Frequency Quadrupole (RFQ) accelerator, with the RFQ sections separated by a magnetic five-dimensional phase-space imaging system as used in an earlier Fermilab/SAIC PET Project, and a new 10-MeV drift-tube linac cavity have been studied. It appears possible that an H{sup {minus}} intensity of 4.5 x 10{sup 13} ions per pulse with an improvement in beam emittance from the present system can be achieved with the proposed changes.

Don E. Young et al.

2001-07-02T23:59:59.000Z

35

Linac Coherent Light SourCe  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Linac Linac Coherent Light SourCe after the Stanford Linear Accelerator Center (now the SLAC National Accelerator Laboratory) developed its two- mile-long linear accelerator (linac), it received approval from the Department of Energy to construct the Linac Coherent Light Source (LCLS), the first free electron laser (FEL) facility that would be able to produce x-rays short and bright enough that individual molecules could be imaged in their natural states. 40 years Genesis of the idea In 1992, Dr. Claudio Pellegrini, a professor at UCLA, first developed a proposal for a facility that would eventually become LCLS. The idea generated interest within the scientific community, and a design study report conducted by SLAC in the late 1990s led to the first

36

High-gradient compact linear accelerator  

DOE Patents (OSTI)

A high-gradient linear accelerator comprises a solid-state stack in a vacuum of five sets of disc-shaped Blumlein modules each having a center hole through which particles are sequentially accelerated. Each Blumlein module is a sandwich of two outer conductive plates that bracket an inner conductive plate positioned between two dielectric plates with different thicknesses and dielectric constants. A third dielectric core in the shape of a hollow cylinder forms a casing down the series of center holes, and it has a dielectric constant different that the two dielectric plates that sandwich the inner conductive plate. In operation, all the inner conductive plates are charged to the same DC potential relative to the outer conductive plates. Next, all the inner conductive plates are simultaneously shorted to the outer conductive plates at the outer diameters. The signal short will propagate to the inner diameters at two different rates in each Blumlein module. A faster wave propagates quicker to the third dielectric core across the dielectric plates with the closer spacing and lower dielectric constant. When the faster wave reaches the inner extents of the outer and inner conductive plates, it reflects back outward and reverses the field in that segment of the dielectric core. All the field segments in the dielectric core are then in unipolar agreement until the slower wave finally propagates to the third dielectric core across the dielectric plates with the wider spacing and higher dielectric constant. During such unipolar agreement, particles in the core are accelerated with gradients that exceed twenty megavolts per meter.

Carder, B.M.

1995-12-31T23:59:59.000Z

37

The Klynac: An Integrated Klystron and Linear Accelerator  

SciTech Connect

The Klynac concept integrates an electron gun, a radio frequency (RF) power source, and a coupled-cavity linear accelerator into a single resonant system

Potter, J. M., Schwellenbach, D., Meidinger, A.

2012-08-07T23:59:59.000Z

38

Drift tube suspension for high intensity linear accelerators  

DOE Patents (OSTI)

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 mounted on each girder.

Liska, D.J.; Schamaun, R.G.; Clark, D.C.; Potter, R.C.; Frank, J.A.

1980-03-11T23:59:59.000Z

39

Variable-energy drift-tube linear accelerator  

SciTech Connect

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 variable-energy drift-tube linear accelerator.

Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM); Potter, James M. (Los Alamos, NM); Stovall, James E. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

40

Drift tube suspension for high intensity linear accelerators  

SciTech Connect

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 mounted on each girder.

Liska, Donald J. (Los Alamos, NM); Schamaun, Roger G. (Los Alamos, NM); Clark, Donald C. (Los Alamos, NM); Potter, R. Christopher (Los Alamos, NM); Frank, Joseph A. (Los Alamos, NM)

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Exact acceleration of linear object detectors  

Science Conference Proceedings (OSTI)

We describe a general and exact method to considerably speed up linear object detection systems operating in a sliding, multi-scale window fashion, such as the individual part detectors of part-based models. The main bottleneck of many of those systems ... Keywords: linear object detection, part-based models

Charles Dubout; Fran$#231;ois Fleuret

2012-10-01T23:59:59.000Z

42

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Useful Links Useful Links Argonne National Laboratory Accelerator Sites Conferences Advanced Photon Source (APS) Argonne Wakefield Accelerator (AWA) Argonne Tandem Linear Accelerator System (ATLAS) High Energy Physics Division RIA (????) Link to JACoW (Joint Accelerator Conferences Website) Fermi National Accelerator Laboratory Fermilab-Argonne Collaboration Accelerator Physics Center Workshops Other Accelerator Institutes Energy Recovering Linacs Center for Advance Studies of Accelerators (Jefferson Labs) Center for Beam Physics (LBNL) Accelerator Test Facility (BNL) The Cockcroft Institute (Daresbury, UK) John Adams Institute (Rutherford, UK) ERL2009 to be held at Cornell ERL2007 ERL2005 DOE Laboratory with Accelerators Fermilab Stanford Linear Accelerator Center Brookhaven National Laboratory

43

LOADED WAVE GUIDES FOR LINEAR ACCELERATORS  

DOE Patents (OSTI)

A periodically loaded waveguide having substantially coaxially arranged elements which provide an axial field for the acceleration of electrons is described. Radiofrequency energy will flow in the space between the inner wall of an outer guide and the peripheries of equally spaced irises or washes arranged coaxially with each other and with the outer guide, where the loading due to the geometry of the irises is such as to reduce the phase velocity of the r-f energy flowing in the guide from a value greater than that of light to the velocity of light or less.

Walkinshaw, W.; Mullett, L.B.

1959-12-01T23:59:59.000Z

44

Considerations for a Dielectric-based Two-beam-accelerator Linear...  

NLE Websites -- All DOE Office Websites (Extended Search)

WEPE033 Proceedings of IPAC'10, Kyoto, Japan 3428 03 Linear Colliders, Lepton Accelerators and New Acceleration Techniques A03 Linear Colliders high coupling coefficient...

45

Radio-frequency quadrupole resonator for linear accelerator  

DOE Patents (OSTI)

An RFQ resonator for a linear accelerator having a reduced level of interfering modes and producing a quadrupole mode for focusing, bunching and accelerating beams of heavy charged particles, with the construction being characterized by four elongated resonating rods within a cylinder with the rods being alternately shorted and open electrically to the shell at common ends of the rods to provide an LC parallel resonant circuit when activated by a magnetic field transverse to the longitudinal axis.

Moretti, A.

1982-10-19T23:59:59.000Z

46

A Non-interceptive Method to Measure Longitudinal Twiss Parameters of a Beam in a Hadron Linear Accelerator using Beam Position Monitors  

Science Conference Proceedings (OSTI)

A new method of measuring of the RMS longitudinal Twiss parameters of a beam in linear accelerators is presented. It is based on using signals from beam position monitors (BPM) sensitive to the second order moment of the longitudinal charge distribution in the bunch. The applicability of the method is demonstrated on the superconducting section of the Oak Ridge Spallation Neutron Source (SNS) linear accelerator. The results are compared to a direct measurement of the bunch longitudinal profiles using an interceptive bunch shape monitor (BSM) in the linac warm section of the same accelerator. Limitations of the method are discussed. The method is fast and simple, and can be used to obtain the initial parameters for the longitudinal matching in linear accelerators where interceptive diagnostics are not desirable.

Aleksandrov, Alexander V [ORNL; Shishlo, Andrei P [ORNL

2013-01-01T23:59:59.000Z

47

Linear Collider Collaboration Tech Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

6, 27/05/99 6, 27/05/99 Tolerances of Random RF Jitters in X-Band Main Linacs May 27, 1999 Kiyoshi KUBO KEK Tsukuba, Japan Abstract: Tracking simulations have been performed for the main linacs of an X-band linear collider. We discuss the choice of phase of the accelerating field relative to the bunches. The tolerances of the phase and the amplitude errors are studied. Tolerances of Random RF Jitters in X-Band Main Linacs K. Kubo, KEK Abstract Tracking simulations have been performed for main linacs of X-band linear collider. We discuss about choice of the phase of the accelerating field relative to the bunches. The tolerances of the phase and the amplitude errors are studied. 1 INTRODUCTION In order to preserve the low emittance through the main linacs of future linear colliders, various effects

48

Construction, Commissioning and Operational Experience of the Advanced Photon Source (APS) Linear Accelerator  

E-Print Network (OSTI)

Construction, Commissioning and Operational Experience of the Advanced Photon Source (APS) Linear Accelerator

White, M; Berg, W; Cours, A; Fuja, R; Grelick, A E; Ko, K; Qian, Y L; Russell, T; Sereno, N S; Wesolowski, W

1996-01-01T23:59:59.000Z

49

Stanford Linear Accelerator Center Stanford Synchrotron Radiation Laboratory  

E-Print Network (OSTI)

1 of 13 10/16/2006 FACILITY EMERGENCY PLAN February, 2006 SSRL Safety Office Stanford Linear Accelerator Center Menlo Park, California TABLE OF CONTENTS PREFACE SSRL EMERGENCY PLAN SECTION A: SAFETY RESPONSIBILITIES 1.0 SSRL Emergency Personnel 1.1 SLAC Person - In - Charge (PIC) 1.2 SSRL Beamline Duty Operator

Ford, James

50

Experimental study of new laser-based alignment system at the KEK B-factory injector linear accelerator  

Science Conference Proceedings (OSTI)

A new laser-based alignment system for the precise alignment of accelerator components along an ideal straight line at the KEK B-factory injector linear accelerator (linac) is under development. This system is strongly required in the next generation of B-factories for the stable acceleration of high-brightness electron and positron beams with high bunch charges and also for maintaining the stability of injection beams with high quality. A new laser optics for the generation of a so-called Airy beam has been developed for the laser-based alignment system. The laser propagation characteristics both in vacuum and at atmospheric pressure have been systematically investigated in an 82-m-long straight section of the injector linac. The laser-based alignment measurements based on the new laser optics have been carried out with a measurement resolution of {+-}0.1 mm level by using an existing laser detection electronics. The horizontal and vertical displacements from a reference laser line measured using this system are in good agreement with those measured using a standard telescope-based optical alignment technique. In this report, we describe the experimental study in detail along with the basic designs and the recent developments in the new laser-based alignment system.

Suwada, T.; Satoh, M.; Kadokura, E. [Accelerator Laboratory, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

2010-12-15T23:59:59.000Z

51

SLAC Linac Coherent Light Source  

NLE Websites -- All DOE Office Websites (Extended Search)

LCLS Sign In Launch the Developer Dashboard SLAC National Accelerator Laboratory DOE | Stanford | SLAC | SSRL | LCLS | AD | PPA | Photon Science | PULSE | SIMES LCLS : Linac...

52

Phase and amplitude detection system for the Stanford Linear Accelerator  

Science Conference Proceedings (OSTI)

A computer controlled phase and amplitude detection system to measure and stabilize the rf power sources in the Stanford Linear Accelerator is described. This system measures the instantaneous phase and amplitude of a 1 microsecond 2856 MHz rf pulse and will be used for phase feedback control and for amplitude and phase jitter detection. This paper discusses the measurement system performance requirements for the operation of the Stanford Linear Collider, and the design and implementation of the phase and amplitude detection system. The fundamental software algorithms used in the measurement are described, as is the performance of the prototype phase and amplitude detector system.

Fox, J.D.; Schwarz, H.D.

1983-01-01T23:59:59.000Z

53

Linear induction accelerator and pulse forming networks therefor  

DOE Green Energy (OSTI)

A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities.

Buttram, Malcolm T. (Sandia Park, NM); Ginn, Jerry W. (Albuquerque, NM)

1989-01-01T23:59:59.000Z

54

Electron Linac Offers Safe, Affordable Production Method for ...  

Biomass and Biofuels; Building Energy Efficiency; ... The electron beam in Linac 2 is also transmitted through the same target then collected in Linac 1 to accelerate ...

55

Linear Collider Collaboration Tech Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

Notes Notes LCC - 0018, 15/06/99 Rev B, June 2002 Correct Account of RF Deflections in Linac Acceleration June 15, 1999 G.V. Stupakov Stanford Linear Accelerator Center Stanford, California Abstract: During acceleration in the linac structure, the beam not only increases its longitudinal momentum, but also experiences a transverse kick from the accelerating mode which is linear in accelerating gradient. This effect is neglected in such computer codes as LIAR and TRANSPORT. We derived the Hamiltonian equations that describe the effect of RF deflection into the acceleration process and included it into the computational engine of LIAR. By comparing orbits for the NLC main linac, we found that the difference between the two algorithms is about 10\%. The effect will be more pronounced at smaller

56

Photon beam quality variations of a flattening filter free linear accelerator  

Science Conference Proceedings (OSTI)

Purpose: Recently, there has been an increasing interest in operating conventional linear accelerators without a flattening filter. The aim of this study was to determine beam quality variations as a function of off-axis ray angle for unflattened beams. In addition, a comparison was made with the off-axis energy variation in flattened beams. Methods: Two Elekta Precise linear accelerators were modified in order to enable radiation delivery with and without the flattening filter in the beam line. At the Medical University Vienna (Vienna, Austria), half value layer (HVL) measurements were performed for 6 and 10 MV with an in-house developed device that can be easily mounted on the gantry. At St. Luke's Hospital (Dublin, Ireland), measurements were performed at 6 MV in narrow beam geometry with the gantry tilted around 270 deg. with pinhole collimators, an attenuator, and the chamber positioned on the table. All attenuation measurements were performed with ionization chambers and a buildup cap (2 mm brass) or a PMMA mini phantom (diameter 3 cm, measurement depth 2.5 cm). Results: For flattened 6 and 10 MV photon beams from the Elekta linac the relative HVL({theta}) varies by about 11% for an off-axis ray angle {theta}=10 deg. These results agree within {+-}2% with a previously proposed generic off-axis energy correction. For unflattened beams, the variation was less than 5% in the whole range of off-axis ray angles up to 10 deg. The difference in relative HVL data was less than 1% for unflattened beams at 6 and 10 MV. Conclusions: Off-axis energy variation is rather small in unflattened beams and less than half the one for flattened beams. Thus, ignoring the effect of off-axis energy variation for dose calculations in unflattened beams can be clinically justified.

Georg, Dietmar; Kragl, Gabriele; Wetterstedt, Sacha af; McCavana, Patrick; McClean, Brendan; Knoeoes, Tommy [Department of Radiotherapy, Division Medical Radiation Physics, Medical University of Vienna, AKH Vienna, 1090 Vienna (Austria); Department of Radiotherapy, St Luke's Hospital, Dublin 6 (Ireland); Radiation Physics, Lund University and Lund University Hospital, 22185 Lund (Sweden)

2010-01-15T23:59:59.000Z

57

Critical design issues of high intensity proton linacs  

SciTech Connect

Medium-energy proton linear accelerators are being studied as drivers for spallation applications requiring large amounts of beam powder. Important design factors for such high-intensity linacs are reviewed, and issues and concerns specific to this unprecedented power regime are discussed.

Lawrence, G.P.

1994-08-01T23:59:59.000Z

58

Overview and status of RF systems for the SSC Linac  

SciTech Connect

The Superconducting Super Collider (SSC) Linear Accelerator (Linac) produces a 600-MeV, 35-{mu}s, H-beam at a 10-Hz repetition rate. The beam is accelerated by a series of RF cavities. These consist of a Radio Frequency Quadrupole (RFQ), two bunchers, and four Drift Tube Linac (DTL) tanks at 427.617 MHz, and two bunchers, nine side-coupled Linac modules, and an energy compressor at 1282.851 MHz. The RFQ amplifier and the low-frequency buncher cavity amplifiers use gridded tubes, while the other cavities use klystron amplifier systems. The RF control system consists of a reference line and cavity feedback and feedforward loops for each amplifier. The RF amplifier system for each of these accelerator cavities is described, and the current status of each system is presented.

Mynk, J.; Grippe, J.; Cutler, R.I.; Rodriguez, R.

1993-05-01T23:59:59.000Z

59

Cryogen free superconducting splittable quadrupole magnet for linear accelerators  

SciTech Connect

A new superconducting quadrupole magnet for linear accelerators was fabricated at Fermilab. The magnet is designed to work inside a cryomodule in the space between SCRF cavities. SCRF cavities must be installed inside a very clean room adding issues to the magnet design, and fabrication. The designed magnet has a splittable along the vertical plane configuration and could be installed outside of the clean room around the beam pipe previously connected to neighboring cavities. For more convenient assembly and replacement a 'superferric' magnet configuration with four racetrack type coils was chosen. The magnet does not have a helium vessel and is conductively cooled from the cryomodule LHe supply pipe and a helium gas return pipe. The quadrupole generates 36 T integrated magnetic field gradient, has 600 mm effective length, and the peak gradient is 54 T/m. In this paper the quadrupole magnetic, mechanical, and thermal designs are presented, along with the magnet fabrication overview and first test results.

Kashikhin, V.S.; Andreev, N.; Kerby, J.; Orlov, Y.; Solyak, N.; Tartaglia, M.; Velev, G.; /Fermilab

2011-09-01T23:59:59.000Z

60

Novel Approach to Linear Accelerator Superconducting Magnet System  

SciTech Connect

Superconducting Linear Accelerators include a superconducting magnet system for particle beam transportation that provides the beam focusing and steering. This system consists of a large number of quadrupole magnets and dipole correctors mounted inside or between cryomodules with SCRF cavities. Each magnet has current leads and powered from its own power supply. The paper proposes a novel approach to magnet powering based on using superconducting persistent current switches. A group of magnets is powered from the same power supply through the common, for the group of cryomodules, electrical bus and pair of current leads. Superconducting switches direct the current to the chosen magnet and close the circuit providing the magnet operation in a persistent current mode. Two persistent current switches were fabricated and tested. In the paper also presented the results of magnetic field simulations, decay time constants analysis, and a way of improving quadrupole magnetic center stability. Such approach substantially reduces the magnet system cost and increases the reliability.

Kashikhin, Vladimir; /Fermilab

2011-11-28T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Improvements in dose accuracy delivered with static-MLC IMRT on an integrated linear accelerator control system  

Science Conference Proceedings (OSTI)

Purpose: Dose accuracy has been shown to vary with dose per segment and dose rate when delivered with static multileaf collimator (SMLC) intensity modulated radiation therapy (IMRT) by Varian C-series MLC controllers. The authors investigated the impact of monitor units (MUs) per segment and dose rate on the dose delivery accuracy of SMLC-IMRT fields on a Varian TrueBeam linear accelerator (LINAC), which delivers dose and manages motion of all components using a single integrated controller. Methods: An SMLC sequence was created consisting of ten identical 10 x 10 cm{sup 2} segments with identical MUs. Beam holding between segments was achieved by moving one out-of-field MLC leaf pair. Measurements were repeated for various combinations of MU/segment ranging from 1 to 40 and dose rates of 100-600 MU/min for a 6 MV photon beam (6X) and dose rates of 800-2400 MU/min for a 10 MV flattening-filter free photon (10XFFF) beam. All measurements were made with a Farmer (0.6 cm{sup 3}) ionization chamber placed at the isocenter in a solid-water phantom at 10 cm depth. The measurements were performed on two Varian LINACs: C-series Trilogy and TrueBeam. Each sequence was delivered three times and the dose readings for the corresponding segments were averaged. The effects of MU/segment, dose rate, and LINAC type on the relative dose variation ({Delta}{sub i}) were compared using F-tests ({alpha} = 0.05). Results: On the Trilogy, large {Delta}{sub i} was observed in small MU segments: at 1 MU/segment, the maximum {Delta}{sub i} was 10.1% and 57.9% at 100 MU/min and 600 MU/min, respectively. Also, the first segment of each sequence consistently overshot ({Delta}{sub i} > 0), while the last segment consistently undershot ({Delta}{sub i} dose rates greater than 100 MU/min. The linear trend of decreasing dose accuracy as a function of increasing dose rate on the Trilogy is no longer apparent on TrueBeam, even for dose rates as high as 2400 MU/min. Dose inaccuracy averaged over all ten segments in each beam delivery sequence was larger for Trilogy than TrueBeam, with the largest discrepancy (0.2% vs 3%) occurring for 1 MU/segment beams at both 300 and 600 MU/min. Conclusions: Earlier generations of Varian LINACs exhibited large dose variations for small MU segments in SMLC-IMRT delivery. Our results confirmed these findings. The dose delivery accuracy for SMLC-IMRT is significantly improved on TrueBeam compared to Trilogy for every combination of low MU/segment (1-10) and high dose rate (200-600 MU/min), in part due to the faster sampling rate (100 vs 20 Hz) and enhanced electronic integration of the MLC controller with the LINAC. SMLC-IMRT can be implemented on TrueBeam with higher dose accuracy per beam ({+-}0.2% vs {+-}3%) than previous generations of Varian C-series LINACs for 1 MU/segment delivered at 600 MU/min).

Li Ji; Wiersma, Rodney D.; Stepaniak, Christopher J.; Farrey, Karl J.; Al-Hallaq, Hania A. [Department of Radiation and Cellular Oncology, University of Chicago, 5758 South Maryland Avenue, MC9006, Chicago, Illinois 60637 (United States)

2012-05-15T23:59:59.000Z

62

2011 Annual Planning Summary for Stanford Linear Accelerator Center Site Office (SLAC)  

Energy.gov (U.S. Department of Energy (DOE))

The ongoing and projected Environmental Assessments and Environmental Impact Statements for 2011 and 2012 within the Stanford Linear Accelerator Center Site Office (SLAC SO) (See also Science).

63

Environmental Survey preliminary report, Stanford Linear Accelerator Center, Stanford, California  

SciTech Connect

This report presents the preliminary findings from the first phase of the Survey of the US Department of Energy (DOE) Stanford Linear Accelerator Center (SLAC) at Stanford, California, conducted February 29 through March 4, 1988. The Survey is being conducted by an interdisciplinary team of environmental specialists, led and managed by the Office of Environment, Safety and Health's Office of Environmental Audit. Individual team components are being supplied by a private contractor. The objective of the Survey is to identify environmental problems and areas of environmental risk associated with the SLAC. The Survey covers all environmental media and all areas of environmental regulation and is being performed in accordance with the DOE Environmental Survey Manual. This phase of the Survey involves the review of existing site environmental data, observations of the operations at the SLAC, and interviews with site personnel. The Survey team is developing a Sampling and Analysis Plan to assist in further assessing certain of the environmental problems identified during its on-site activities. The Sampling and Analysis Plan will be executed by a DOE National Laboratory or a support contractor. When completed, the results will be incorporated into the Environmental Survey Interim Report for the SLAC facility. The Interim Report will reflect the final determinations of the SLAC Survey. 95 refs., 25 figs., 25 tabs.

Not Available

1988-07-01T23:59:59.000Z

64

NSLS Booster & Linac Ring  

NLE Websites -- All DOE Office Websites (Extended Search)

Booster & Linac Ring Booster & Linac Ring Booster Operating Parameters (pdf) Lattice Information (pdf) Mechanical Drawing (pdf) Standard Operating Mode Electrons are injected into the NSLS storage rings from a 750 MeV booster synchrotron fed by a 120 MeV linac. The electrons are first produced in a 100 KeV triode electron gun. The gun is pulsed at the booster revolution period, 94.6 nsec, seven times per booster cycle. Each pulse is 5 nsec long and supplies about 17 microbunches in the linac. After acceleration in the linac, the beam is injected into the booster on seven successive turns. Multi-turn injection in the booster is accomplished in the following way: The beam is deflected into the booster by a septum magnet. The first linac pulse goes around the booster and returns to the injection point just as

65

Nuclear Data for Criticality Safety and Reactor Applications at the Gaerttner LINAC Center Y. Danon, R.M. Bahran, E.J. Blain, A.M. Daskalakis, B.J. McDermott, D.G. Williams  

E-Print Network (OSTI)

Nuclear Data for Criticality Safety and Reactor Applications at the Gaerttner LINAC Center Y. Danon INTRODUCTION The Rensselaer Polytechnic Institute (RPI) nuclear data program utilizes a 60 MeV pulsed electron Linear Accelerator (LINAC) to produce short pulses of neutrons for nuclear data measurements1 . Neutron

Danon, Yaron

66

Tuning the DARHT Axis-II linear induction accelerator focusing  

SciTech Connect

Flash radiography of large hydrodynamic experiments driven by high explosives is a well-known diagnostic technique in use at many laboratories, and the Dual-Axis Radiography for Hydrodynamic Testing (DARHT) facility at Los Alamos produces flash radiographs of large hydrodynamic experiments. Two linear induction accelerators (LIAs) make the bremsstrahlung radiographic source spots for orthogonal views of each test. The 2-kA, 20-MeV Axis-I LIA creates a single 60-ns radiography pulse. The 1.7-kA, 16.5-MeV Axis-II LIA creates up to four radiography pulses by kicking them out of a longer pulse that has a 1.6-{mu}s flattop. The Axis-II injector, LIA, kicker, and downstream transport (DST) to the bremsstrahlung converter are described. Adjusting the magnetic focusing and steering elements to optimize the electron-beam transport through an LIA is often called 'tuning.' As in all high-current LIAs, the focusing field is designed to be as close to that of the ideal continuous solenoid as physically possible. In ideal continuous solenoidal transport a smoothly varying beam size can easily be found for which radial forces balance, and the beam is said to be 'matched' to the focusing field. A 'mismatched' beam exhibits unwanted oscillations in size, which are a source of free energy that contributes to emittance growth. This is undesirable, because in the absence of beam-target effects, the radiographic spot size is proportional to the emittance. Tuning the Axis-II LIA is done in two steps. First, the solenoidal focusing elements are set to values designed to provide a matched beam with little or no envelope oscillations, and little or no beam-breakup (BBU) instability growth. Then, steering elements are adjusted to minimize the motion of the centroid of a well-centered beam at the LIA exit. This article only describes the design of the tune for the focusing solenoids. The DARHT Axis-II LIA was required to be re-tuned after installing an accelerator cell to replace a failed solenoid in March of 2012. We took advantage of this opportunity to improve the design of the focusing tune with better models of the remaining partially failed solenoids, better estimates of beam initial conditions, and better values for pulsed-power voltages. As with all previous tunes for Axis-II, this one incorporates measures to mitigate beam-breakup (BBU) instability, image displacement instability (IDI), corkscrew (sweep), and emittance growth. Section II covers the general approach to of design of focusing solenoid tunes for the DARHT Axis-2 LIA. Section III explains the specific requirements and simulations needed to design the tune for the injector, which includes the thermionic electron source, diode, and six induction cells. Section IV explains the requirements and simulations for tuning the main accelerator, which consists of 68 induction cells. Finally, Section V explores sensitivity of the tune to deviations of parameters from nominal, random variations, and uncertainties in values. Four appendices list solenoid settings for this new tune, discuss comparisons of different simulation codes, show halo formation in mismatched beams, and present a brief discussion of the beam envelope equation, which is the heart of the method used to design LIA solenoid tunes.

Ekdahl, Carl A. [Los Alamos National Laboratory

2012-04-24T23:59:59.000Z

67

Failure Analysis of the Beam Vacuum in the Superconducting Cavities of the TESLA Main Linear Accelerator  

E-Print Network (OSTI)

1 Failure Analysis of the Beam Vacuum in the Superconducting Cavities of the TESLA Main Linear Hamburg, Germany Abstract For the long term successful operation of the superconducting TESLA accelerator The beam vacuum system of the TESLA main linear accelerators contains about 20.000 superconducting cavities

68

Overview of the High Intensity Neutrino Source Linac R&D program at Fermilab  

SciTech Connect

The Fermilab High Intensity Neutrino Source (HINS) Linac R&D program is building a first-of-a-kind 60 MeV superconducting H- linac. The HINS Linac incorporates superconducting solenoids for transverse focusing, high power RF vector modulators for independent control of multiple cavities powered from a single klystron, and superconducting spoke-type accelerating cavities starting at 10 MeV. This will be the first application and demonstration of any of these technologies in a low-energy, high-intensity proton/H- linear accelerator. The HINS effort is relevant to a high intensity, superconducting H- linac that might serve the next generation of neutrino physics and muon storage ring/collider experiments. An overview of the HINS program, machine design, status, and outlook is presented.

Webber, R.C.; Appollinari, G.; Carneiro, J.P.; Gonin, I.; Hanna, B.; Hays, S.; Khabiboulline, T.; Lanfranco, G.; Madrak, R.L.; Moretti, A.; Nicol, T.; /Fermilab /Argonne

2008-09-01T23:59:59.000Z

69

Muon Acceleration - RLA and FFAG  

SciTech Connect

Various acceleration schemes for muons are presented. The overall goal of the acceleration systems: large acceptance acceleration to 25 GeV and 'beam shaping' can be accomplished by various fixed field accelerators at different stages. They involve three superconducting linacs: a single pass linear Pre-accelerator followed by a pair of multi-pass Recirculating Linear Accelerators (RLA) and finally a non-scaling FFAG ring. The present baseline acceleration scenario has been optimized to take maximum advantage of appropriate acceleration scheme at a given stage. The solenoid based Pre-accelerator offers very large acceptance and facilitates correction of energy gain across the bunch and significant longitudinal compression trough induced synchrotron motion. However, far off-crest acceleration reduces the effective acceleration gradient and adds complexity through the requirement of individual RF phase control for each cavity. The RLAs offer very efficient usage of high gradient superconducting RF and ability to adjust path-length after each linac pass through individual return arcs with uniformly periodic FODO optics suitable for chromatic compensation of emittance dilution with sextupoles. However, they require spreaders/recombiners switchyards at both linac ends and significant total length of the arcs. The non-scaling Fixed Field Alternating Gradient (FFAG) ring combines compactness with very large chromatic acceptance (twice the injection energy) and it allows for large number of passes through the RF (at least eight, possibly as high as 15).

Alex Bogacz

2011-10-01T23:59:59.000Z

70

Radio frequency pulse compression experiments at SLAC (Stanford Linear Accelerator Center)  

Science Conference Proceedings (OSTI)

Proposed future positron-electron linear colliders would be capable of investigating fundamental processes of interest in the 0.5--5 TeV beam-energy range. At the SLAC Linear Collider (SLC) gradient of about 20 MV/m this would imply prohibitive lengths of about 50--250 kilometers per linac. We can reduce the length by increasing the gradient but this implies high peak power, on the order of 400-- to 1000-MW at X-Band. One possible way to generate high peak power is to generate a relatively long pulse at a relatively low power and compress it into a short pulse with higher peak power. It is possible to compress before DC to RF conversion, as is done using magnetic switching for induction linacs, or after DC to RF conversion, as is done for the SLC. Using RF pulse compression it is possible to boost the 50-- to 100-MW output that has already been obtained from high-power X-Band klystrons the levels required by the linear colliders. In this note only radio frequency pulse compression (RFPC) is considered.

Farkas, Z.D.; Lavine, T.L.; Menegat, A.; Miller, R.H.; Nantista, C.; Spalek, G.; Wilson, P.B.

1991-01-01T23:59:59.000Z

71

Towards dense linear algebra for hybrid GPU accelerated manycore systems  

Science Conference Proceedings (OSTI)

We highlight the trends leading to the increased appeal of using hybrid multicore+GPU systems for high performance computing. We present a set of techniques that can be used to develop efficient dense linear algebra algorithms for these systems. We illustrate ... Keywords: Dense linear algebra, Graphics processing units, Hybrid computing, Multicore processors, Parallel algorithms

Stanimire Tomov; Jack Dongarra; Marc Baboulin

2010-06-01T23:59:59.000Z

72

Dynamic MLC leaf sequencing for integrated linear accelerator control systems  

Science Conference Proceedings (OSTI)

Purpose: Leaf positions for dynamic multileaf collimator (DMLC) intensity modulated radiation therapy must be closely synchronized with MU delivery. For the Varian C3 series MLC controller, if the planned trajectory (leaf position vs. MU) requires velocities exceeding the capability of the MLC, the leaves fall behind the planned positions, causing the controller to momentarily hold the beam and thereby introduce dosimetric errors. We investigated the merits of a new commercial linear accelerator, TrueBeam, that integrates MLC control with prospective dose rate modulation. If treatment is delivered at dose rates so high that leaves would fall behind, the controller reduces the dose rate such that harmony between MU and leaf position is preserved. Methods: For three sets of DMLC leaf trajectories, point doses and two-dimensional dose distributions were measured in phantom using an ionization chamber and film, respectively. The first set, delivered using both a TrueBeam and a conventional C3 controller, comprised a single leaf bank closing at planned velocities of 2.4, 7.1, and 14 cm/s. The maximum achievable leaf velocity for both systems was 3 cm/s. The remaining two sets were derived from clinical fluence maps using a commercial treatment planning system for a range of planned dose rates and were delivered using TrueBeam set to the maximum dose rate, 600 MU/min. Generating trajectories using a planned dose rate that is lower than the delivery dose rate effectively increased the leaf velocity constraint used by the planning system for trajectory calculation. The second set of leaf trajectories was derived from two fluence maps containing regions of zero fluence obtained from representative beams of two different patient treatment plans. The third set was obtained from all nine fields of a head and neck treatment plan. For the head and neck plan, dose-volume histograms of the spinal cord and target for each planned dose rate were obtained. Results: For the single closing leaf bank trajectories, the TrueBeam control system reduced the dose rate such that the leaf velocity was less than the maximum. Dose deviations relative to the 2.4 cm/s trajectory were less than 3%. For the conventional controller, the leaves repeatedly fell behind the planned positions until the beam hold threshold was reached, resulting in deviations of up to 19% relative to the 2.4 cm/s trajectory. For the two clinical fluence maps, reducing the planned dose rate reduced the dose in the zero fluence regions by 15% and 24% and increased the delivery time by 5 s and 14 s. No significant differences were noted in the high and intermediate dose regions measured using film. The DVHs for the head and neck plan showed a 10% reduction in cord dose for 20 MU/min relative to 600 MU/min sequencing dose rate, which was confirmed by measurement. No difference in target DVHs were observed. The reduction in cord dose increased total treatment time by 1.8 min. Conclusions: Leaf sequencing algorithms for integrated control systems should be modified to reflect the reduced importance of maximum leaf velocity for accurate dose delivery.

Popple, Richard A.; Brezovich, Ivan A. [Department of Radiation Oncology, University of Alabama at Birmingham, 1700 6th Avenue South, Birmingham, Alabama 35249-6832 (United States)

2011-11-15T23:59:59.000Z

73

FLUKA calculations of radionuclides, star, and neutron fluence in soil around high-energy electron and proton linear accelerators  

E-Print Network (OSTI)

FLUKA calculations of radionuclides, star, and neutron fluence in soil around high-energy electron and proton linear accelerators

Puryear, A; Rokni, S H

2002-01-01T23:59:59.000Z

74

DOE - Office of Legacy Management -- Yale Heavy Ion Linear Accelerator - CT  

NLE Websites -- All DOE Office Websites (Extended Search)

Yale Heavy Ion Linear Accelerator - Yale Heavy Ion Linear Accelerator - CT 05 FUSRAP Considered Sites Site: Yale Heavy Ion Linear Accelerator (CT.05) Eliminated from consideration under FUSRAP Designated Name: Not Designated Alternate Name: None Location: New Haven , Connecticut CT.05-1 Evaluation Year: 1987 CT.05-3 Site Operations: Research and development with solvents. CT.05-1 Site Disposition: Eliminated - Potential for contamination remote based on limited amount of materials handled CT.05-3 Radioactive Materials Handled: Yes Primary Radioactive Materials Handled: Uranium, Radium CT.05-1 Radiological Survey(s): No Site Status: Eliminated from consideration under FUSRAP Also see Documents Related to Yale Heavy Ion Linear Accelerator CT.05-1 - MED Memorandum; To the Files, Thru Ruhoff, et. al.;

75

Accelerated Iterative Method for Solving Steady Problems of Linearized Atmospheric Models  

Science Conference Proceedings (OSTI)

A new approach, referred to as the accelerated iterative method (AIM), is developed for obtaining steady atmospheric responses with a zonally varying basic state. The linear dynamical operator is divided into two parts, one associated with the ...

Masahiro Watanabe; Fei-fei Jin; Lin Pan

2006-12-01T23:59:59.000Z

76

Neutron-induced electronic failures around a high-energy linear accelerator  

Science Conference Proceedings (OSTI)

Purpose: After a new in-vault CT-on-rails system repeatedly malfunctioned following use of a high-energy radiotherapy beam, we investigated the presence and impact of neutron radiation on this electronic system, as well as neutron shielding options. Methods: We first determined the CT scanner's failure rate as a function of the number of 18 MV monitor units (MUs) delivered. We then re-examined the failure rate with both 2.7-cm-thick and 7.6-cm-thick borated polyethylene (BPE) covering the linac head for neutron shielding. To further examine shielding options, as well as to explore which neutrons were relevant to the scanner failure, Monte Carlo simulations were used to calculate the neutron fluence and spectrum in the bore of the CT scanner. Simulations included BPE covering the CT scanner itself as well as covering the linac head. Results: We found that the CT scanner had a 57% chance of failure after the delivery of 200 MUs. While the addition of neutron shielding to the accelerator head reduced this risk of failure, the benefit was minimal and even 7.6 cm of BPE was still associated with a 29% chance of failure after the delivery of 200 MU. This shielding benefit was achieved regardless of whether the linac head or CT scanner was shielded. Additionally, it was determined that fast neutrons were primarily responsible for the electronic failures. Conclusions: As illustrated by the CT-on-rails system in the current study, physicists should be aware that electronic systems may be highly sensitive to neutron radiation. Medical physicists should therefore monitor electronic systems that have not been evaluated for potential neutron sensitivity. This is particularly relevant as electronics are increasingly common in the therapy vault and newer electronic systems may exhibit increased sensitivity.

Kry, Stephen F.; Johnson, Jennifer L.; White, R. Allen; Howell, Rebecca M.; Kudchadker, Rajat J.; Gillin, Michael T. [Department of Radiation Physics, M. D. Anderson Cancer Center, University of Texas, 1515 Holcombe Boulevard, Houston, Texas 77030 and Health Science Center Houston, Graduate School of Biomedical Sciences, University of Texas Health Science Center Houston, Houston, Texas 77030 (United States); Department of Radiation Physics, M. D. Anderson Cancer Center, University of Texas, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Department of Biostatistics and Applied Mathematics, M. D. Anderson Cancer Center, University of Texas, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States) and Health Science Center Houston, Graduate School of Biomedical Sciences, University of Texas, Houston, Texas 77030 (United States); Department of Radiation Physics, M. D. Anderson Cancer Center, University of Texas, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States) and Health Science Center Houston, Graduate School of Biomedical Sciences, University of Texas, Houston, Texas 77030 (United States); Department of Radiation Physics, M. D. Anderson Cancer Center, University of Texas, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States)

2011-01-15T23:59:59.000Z

77

EA-1087: Proposed Induction Linac System Experiments in Building 51B at  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

7: Proposed Induction Linac System Experiments in Building 7: Proposed Induction Linac System Experiments in Building 51B at Lawrence Berkeley National Laboratory, Berkeley, California EA-1087: Proposed Induction Linac System Experiments in Building 51B at Lawrence Berkeley National Laboratory, Berkeley, California SUMMARY This EA evaluates the environmental impacts of a proposal to modify existing Building 51B at the U.S. Department of Energy's Lawrence Berkeley National Laboratory to install and conduct experiments on a new Induction Linear Accelerator System. PUBLIC COMMENT OPPORTUNITIES None available at this time. DOCUMENTS AVAILABLE FOR DOWNLOAD September 8, 1995 EA-1087: Finding of No Significant Impact Proposed Induction Linac System Experiments in Building 51B at Lawrence Berkeley National Laboratory, Berkeley, California

78

Superstructure for high current applications in superconducting linear accelerators  

DOE Patents (OSTI)

A superstructure for accelerating charged particles at relativistic speeds. The superstructure consists of two weakly coupled multi-cell subunits equipped with HOM couplers. A beam pipe connects the subunits and an HOM damper is included at the entrance and the exit of each of the subunits. A coupling device feeds rf power into the subunits. The subunits are constructed of niobium and maintained at cryogenic temperatures. The length of the beam pipe between the subunits is selected to provide synchronism between particles and rf fields in both subunits.

Sekutowicz, Jacek (Elbchaussee, DE); Kneisel, Peter (Williamsburg, VA)

2008-03-18T23:59:59.000Z

79

Emittance Measurement and Modeling of the ALS 50 MeV Linac to Booster Line  

E-Print Network (OSTI)

Measurement and Modeling of the ALS 50 Me V Linac to Boosterhave been measured for the ALS LINAC through non-linear X2Measurement and Modeling of the ALS 50 Me V Linac to Booster

Bengtsson, J.

2011-01-01T23:59:59.000Z

80

The First Observation of Intra Beam Stripping of Negative Hydrogen in a Superconducting Linear Accelerator  

Science Conference Proceedings (OSTI)

We report on an experiment in which a negative hydrogen ions beam in the Spallation Neutron Source (SNS) linear accelerator was replaced with a beam of protons with similar size and dynamics. Beam loss in the superconducting part of the SNS accelerator was at least an order of magnitude lower for the proton beam. Also beam loss has a stronger dependence on intensity with H- than with proton beams. These measurements verify a recent theoretical explanation of unexpected beam losses in the SNS superconducting linear accelerator based on an intra beam stripping mechanism for negative hydrogen ions. An identification of the new physics mechanism for beam loss is important for the design of new high current linear ion accelerators and the performance improvement of existing machines

Aleksandrov, Alexander V [ORNL; Plum, Michael A [ORNL; Shishlo, Andrei P [ORNL; Galambos, John D [ORNL

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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81

Focusing solenoid for the front end of a linear RF accelerator  

SciTech Connect

A prototype of a superconducting focusing solenoid for use in an RF linac has been built and tested at Fermi National Accelerator Laboratory (FNAL). The solenoid is comprised of the main coil, two bucking coils, two dipole corrector windings, and a low carbon steel flux return. At the excitation current of 250 A, the magnetic field reaches 7.2 T in the center of the solenoid and is less than 5 G on the axis at a distance of 150 mm from the center. The length of the solenoid is 150 mm; the length of a cryovessel for the solenoid with a 20 mm diameter 'warm' bore is 270 mm. This paper presents the main design features of the focusing solenoid and discusses results from tests of the solenoid.

Terechkine, I.; Kashikhin, V.V.; Page, T.; Tartaglia, M.; Tompkins, J.; /Fermilab

2007-06-01T23:59:59.000Z

82

Linearized error analysis for an accelerator and application to the APS injector synchrotron  

SciTech Connect

This paper presents a tolerance budget for accelerators dictated by the linear transverse dynamics of particle motion. The linearized equations satisfied by the particle motion when errors in the lattice are present are given along with the solution to these equations. The forms of these errors giving rise to the linearized equation are stated. These results are used to derive a tolerance budget for the Advanced Photon Source (APS) injector synchrotron.

Koul, R.K.; Mills, F.E.

1995-07-01T23:59:59.000Z

83

Hippocampal-Sparing Whole-Brain Radiotherapy: A 'How-To' Technique Using Helical Tomotherapy and Linear Accelerator-Based Intensity-Modulated Radiotherapy  

SciTech Connect

Purpose: Sparing the hippocampus during cranial irradiation poses important technical challenges with respect to contouring and treatment planning. Herein we report our preliminary experience with whole-brain radiotherapy using hippocampal sparing for patients with brain metastases. Methods and Materials: Five anonymous patients previously treated with whole-brain radiotherapy with hippocampal sparing were reviewed. The hippocampus was contoured, and hippocampal avoidance regions were created using a 5-mm volumetric expansion around the hippocampus. Helical tomotherapy and linear accelerator (LINAC)-based intensity-modulated radiotherapy (IMRT) treatment plans were generated for a prescription dose of 30 Gy in 10 fractions. Results: On average, the hippocampal avoidance volume was 3.3 cm{sup 3}, occupying 2.1% of the whole-brain planned target volume. Helical tomotherapy spared the hippocampus, with a median dose of 5.5 Gy and maximum dose of 12.8 Gy. LINAC-based IMRT spared the hippocampus, with a median dose of 7.8 Gy and maximum dose of 15.3 Gy. On a per-fraction basis, mean dose to the hippocampus (normalized to 2-Gy fractions) was reduced by 87% to 0.49 Gy{sub 2} using helical tomotherapy and by 81% to 0.73 Gy{sub 2} using LINAC-based IMRT. Target coverage and homogeneity was acceptable with both IMRT modalities, with differences largely attributed to more rapid dose fall-off with helical tomotherapy. Conclusion: Modern IMRT techniques allow for sparing of the hippocampus with acceptable target coverage and homogeneity. Based on compelling preclinical evidence, a Phase II cooperative group trial has been developed to test the postulated neurocognitive benefit.

Gondi, Vinai [Department of Human Oncology, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States); Tolakanahalli, Ranjini [Department of Medical Physics, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States); Mehta, Minesh P. [Department of Human Oncology, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States); Tewatia, Dinesh [Department of Human Oncology, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States); Department of Medical Physics, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States); Rowley, Howard [Department of Neuroradiology, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States); Kuo, John S. [Department of Human Oncology, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States); Department of Neurological Surgery, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States); Khuntia, Deepak [Department of Human Oncology, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States); Tome, Wolfgang A., E-mail: tome@humonc.wisc.ed [Department of Human Oncology, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States); Department of Medical Physics, University of Wisconsin Comprehensive Cancer Center, Madison, WI (United States)

2010-11-15T23:59:59.000Z

84

BEAM DYNAMICS ISSUES IN THE SNS LINAC  

Science Conference Proceedings (OSTI)

A review of the Spallation Neutron Source (SNS) linac beam dynamics is presented. It describes transverse and longitudinal beam optics, losses, activation, and comparison between the initial design and the existing accelerator. The SNS linac consists of normal conducting and superconducting parts. The peculiarities in operations with the superconducting part of the SNS linac (SCL), estimations of total losses in SCL, the possible mechanisms of these losses, and the progress in the transverse matching are discussed.

Shishlo, Andrei P [ORNL

2011-01-01T23:59:59.000Z

85

Measurement of the neutron leakage from a dedicated intraoperative radiation therapy electron linear accelerator and a conventional linear accelerator for 9, 12, 15(16), and 18(20) MeV electron energies  

SciTech Connect

The issue of neutron leakage has recently been raised in connection with dedicated electron-only linear accelerators used for intraoperative radiation therapy (IORT). In particular, concern has been expressed about the degree of neutron production at energies of 10 MeV and higher due to the need for additional, perhaps permanent, shielding in the room in which the device is operated. In particular, three mobile linear accelerators available commercially offer electron energies at or above the neutron threshold, one at 9 MeV, one at 10 MeV, and the third at 12 MeV. To investigate this problem, neutron leakage has been measured around the head of two types of electron accelerators at a distance of 1 m from the target at azimuthal angles of 0 deg., 45 deg., 90 deg., 135 deg., and 180 deg. The first is a dedicated electron-only (nonmobile) machine with electron energies of 6 (not used here), 9, 12, 15, and 18 MeV and the second a conventional machine with electron energies of 6 (also not used here), 9, 12, 16, and 20 MeV. Measurements were made using neutron bubble detectors and track-etch detectors. For electron beams from a conventional accelerator, the neutron leakage in the forward direction in Sv/Gy is 2.1x10{sup -5} at 12 MeV, 1.3x10{sup -4} at 16 MeV, and 4.2x10{sup -4} at 20 MeV, assuming a quality factor (RBE) of 10. For azimuthal angles >0 deg., the leakage is almost angle independent [2x10{sup -6} at 12 MeV; (0.7-1.6)x10{sup -5} at 16 MeV, and (1.6-2.9)x10{sup -5} at 20 MeV]. For the electron-only machine, the neutron leakage was lower than for the conventional linac, but also independent of azimuthal angle for angles >0 deg. : ([0 deg. : 7.7x10{sup -6} at 12 MeV; 3.0x10{sup -5} at 15 MeV; 1.0x10{sup -4} at 18 MeV]; [other angles: (2.6-5.9)x10{sup -7} at 12 MeV; (1.4-2.2)x10{sup -6} at 15 MeV; (2.7-4.7)x10{sup -6} at 18 MeV]). Using the upper limit of 6x10{sup -7} Sv/Gy at 12 MeV for the IORT machine for azimuthal angles >0 deg. and assuming a workload of 200 Gy/wk and an inverse square factor of 10, the neutron dose equivalent is calculated to be 0.012 mSv/wk. For the primary beam at 12 MeV (0 deg. ), the 10x higher dose would be compensated by the attenuation of a primary beam stopper in a mobile linear accelerator. These neutron radiation levels are below regulatory values (National Council on Radiation Protection and Measurements, 'Limitation of exposure to ionizing radiation', NCRP Report No. 116, NCRP Bethesda, MD, 1993)

Jaradat, Adnan K.; Biggs, Peter J. [Department of Physics, University of Massachusetts Lowell, One University Avenue, Lowell, Massachusetts 01854 (United States); Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114 (United States)

2008-05-15T23:59:59.000Z

86

BNL | S-band Linac  

NLE Websites -- All DOE Office Websites (Extended Search)

S-band Linac S-band Linac Some experiments at the ATF require higher energies than what is available from the photoinjector. We use two traveling wave linac structures, known as 'SLAC sections' (from the famous 2-mile SLAC linac). Each section provides an acceleration given by: Energy gain (in MeV) = 10.8*SQRT(Power in MW)-39.5*Current(in amps) The current to be used is an equivalent steady state current. The microwave drive power, at a frequency of 2856 MHz, is provided by a single XK5 klystron tube (the old SLAC klystron). This tube can provide up to 25 MW. The ATF modulator can provide the XK5 klystron with high voltage for about 3 microseconds. This 3 microsecond pulse is called the macropulse. The repetition rate for the macropulses is from 1 to 6 per second. Within each

87

International Linear Collider Accelerator Physics R&D  

Science Conference Proceedings (OSTI)

ILC work at Illinois has concentrated primarily on technical issues relating to the design of the accelerator. Because many of the problems to be resolved require a working knowledge of classical mechanics and electrodynamics, most of our research projects lend themselves well to the participation of undergraduate research assistants. The undergraduates in the group are scientists, not technicians, and find solutions to problems that, for example, have stumped PhD-level staff elsewhere. The ILC Reference Design Report calls for 6.7 km circumference damping rings (which prepare the beams for focusing) using “conventional” stripline kickers driven by fast HV pulsers. Our primary goal was to determine the suitability of the 16 MeV electron beam in the AŘ region at Fermilab for precision kicker studies.We found that the low beam energy and lack of redundancy in the beam position monitor system complicated the analysis of our data. In spite of these issues we concluded that the precision we could obtain was adequate to measure the performance and stability of a production module of an ILC kicker, namely 0.5%. We concluded that the kicker was stable to an accuracy of ~2.0% and that we could measure this precision to an accuracy of ~0.5%. As a result, a low energy beam like that at AŘ could be used as a rapid-turnaround facility for testing ILC production kicker modules. The ILC timing precision for arrival of bunches at the collision point is required to be 0.1 picosecond or better. We studied the bunch-to-bunch timing accuracy of a “phase detector” installed in AŘ in order to determine its suitability as an ILC bunch timing device. A phase detector is an RF structure excited by the passage of a bunch. Its signal is fed through a 1240 MHz high-Q resonant circuit and then down-mixed with the AŘ 1300 MHz accelerator RF. We used a kind of autocorrelation technique to compare the phase detector signal with a reference signal obtained from the phase detector’s response to an event at the beginning of the run. We determined that the device installed in our beam, which was instrumented with an 8-bit 500 MHz ADC, could measure the beam timing to an accuracy of 0.4 picoseconds. Simulations of the device showed that an increase in ADC clock rate to 2 GHz would improve measurement precision by the required factor of four. As a result, we felt that a device of this sort, assuming matters concerning dynamic range and long-term stability can be addressed successfully, would work at the ILC. Cost effective operation of the ILC will demand highly reliable, fault tolerant and adaptive solutions for both hardware and software. The large numbers of subsystems and large multipliers associated with the modules in those subsystems will cause even a strong level of unit reliability to become an unacceptable level of system availability. An evaluation effort is underway to evaluate standards associated with high availability, and to guide ILC development with standard practices and well-supported commercial solutions. One area of evaluation involves the Advanced Telecom Computing Architecture (ATCA) hardware and software. We worked with an ATCA crate, processor monitors, and a small amount of ATCA circuit boards in order to develop a backplane “spy” board that would let us watch the ATCA backplane communications and pursue development of an inexpensive processor monitor that could be used as a physics-driven component of the crate-level controls system. We made good progress, and felt that we had determined a productive direction to extend this work. We felt that we had learned enough to begin designing a workable processor monitor chip if there were to be sufficient interest in ATCA shown by the ILC community. Fault recognition is a challenging issue in the crafting a high reliability controls system. With tens of thousands of independent processors running hundreds of thousands of critical processes, how can the system identify that a problem has arisen and determine the appropriate steps to take to correct, or compensate, for the

George D. Gollin; Michael Davidsaver; Michael J. Haney; Michael Kasten; Jason Chang; Perry Chodash; Will Dluger; Alex Lang; Yehan Liu

2008-09-03T23:59:59.000Z

88

Solving Large Sparse Linear Systems in End-to-end Accelerator Structure Simulations  

Science Conference Proceedings (OSTI)

This paper presents a case study of solving very large sparse linear systems in end-to-end accelerator structure simulations. Both direct solvers and iterative solvers are investigated. A parallel multilevel preconditioner based on hierarchical finite element basis functions is considered and has been implemented to accelerate the convergence of iterative solvers. A linear system with matrix size 93,147,736 and with 3,964,961,944 non-zeros from 3D electromagnetic finite element discretization has been solved in less than 8 minutes with 1024 CPUs on the NERSC IBM SP. The resource utilization as well as the application performance for these solvers is discussed.

Lee, L

2004-01-23T23:59:59.000Z

89

Solving large-scale sparse eigenvalue problems and linear systems of equations for accelerator modeling  

SciTech Connect

The solutions of sparse eigenvalue problems and linear systems constitute one of the key computational kernels in the discretization of partial differential equations for the modeling of linear accelerators. The computational challenges faced by existing techniques for solving those sparse eigenvalue problems and linear systems call for continuing research to improve on the algorithms so that ever increasing problem size as required by the physics application can be tackled. Under the support of this award, the filter algorithm for solving large sparse eigenvalue problems was developed at Stanford to address the computational difficulties in the previous methods with the goal to enable accelerator simulations on then the world largest unclassified supercomputer at NERSC for this class of problems. Specifically, a new method, the Hemitian skew-Hemitian splitting method, was proposed and researched as an improved method for solving linear systems with non-Hermitian positive definite and semidefinite matrices.

Gene Golub; Kwok Ko

2009-03-30T23:59:59.000Z

90

Linac Alignment Algorithm: Analysis on 1-to-1 Steering  

SciTech Connect

In a linear accelerator, it is important to achieve a good alignment between all of its components (such as quadrupoles, RF cavities, beam position monitors et al.), in order to better preserve the beam quality during acceleration. After the survey of the main linac components, there are several beam-based alignment (BBA) techniques to be applied, to further optimize the beam trajectory and calculate the corresponding steering magnets strength. Among these techniques the most simple and straightforward one is the one-to-one (1-to-1) steering technique, which steers the beam from quad center to center, and removes the betatron oscillation from quad focusing. For a future linear collider such as the International Linear Collider (ILC), the initial beam emittance is very small in the vertical plane (flat beam with {gamma}{epsilon}{sub y} = 20-40nm), which means the alignment requirement is very tight. In this note, we evaluate the emittance growth with one-to-one correction algorithm employed, both analytically and numerically. Then the ILC main linac accelerator is taken as an example to compare the vertical emittance growth after 1-to-1 steering, both from analytical formulae and multi-particle tracking simulation. It is demonstrated that the estimated emittance growth from the derived formulae agrees well with the results from numerical simulation, with and without acceleration, respectively.

Sun, Yipeng; Adolphsen, Chris; /SLAC

2011-08-19T23:59:59.000Z

91

(Stanford Linear Accelerator Center) annual environmental monitoring report, January--December 1989  

SciTech Connect

This progress report discusses environmental monitoring activities at the Stanford Linear Accelerator Center for 1989. Topics include climate, site geology, site water usage, land use, demography, unusual events or releases, radioactive and nonradioactive releases, compliance summary, environmental nonradiological program information, environmental radiological program information, groundwater protection monitoring ad quality assurance. 5 figs., 7 tabs. (KJD)

Not Available

1990-05-01T23:59:59.000Z

92

A Linear Analysis on the Acceleration of Zonal Flow by Baroclinic Instability. Part I. Terrestrial Atmosphere  

Science Conference Proceedings (OSTI)

A mechanism which accelerates the midlatitude zonal-mean wind is investigated by means of linear stability analysis for the wave-zonal flow interaction. Two kinds of models are analyzed: In the first, the basic state consists of an unstable zonal-...

T. Sasamori; K. Droegemeier

1983-10-01T23:59:59.000Z

93

Klystron-linac combination  

DOE Patents (OSTI)

A combination klystron-linear accelerator which utilizes anti-bunch electrons generated in the klystron section as a source of electrons to be accelerated in the accelerator section. Electron beam current is controlled by second harmonic bunching, constrictor aperture size and magnetic focusing. Rf coupling is achieved by internal and external coupling.

Stein, W.E.

1980-04-24T23:59:59.000Z

94

Alternating phase focused linacs  

SciTech Connect

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 acceleration and succession of focusing and defocusing forces which contain the beam without additional magnetic or electric focusing fields.

Swenson, Donald A. (Los Alamos, NM)

1980-01-01T23:59:59.000Z

95

High-power accelerator technology and requirements  

SciTech Connect

Designs of high-power proton linear accelerators (linacs) for accelerator transmutation of waste (ATW) are being actively studied at Los Alamos National Laboratory and at several other laboratories worldwide. Beam parameters cover the 100- to 300-mA range in average current and 800 to 1600 MeV in energy. While ideas for such accelerators have been discussed for decades, the technology base has recently advanced to the point that the feasibility of machines in the ATW power class is now generally conceded. Factors contributing to this advance have been the following: experience gained with medium-power research accelerators, especially the LAMPF linac at Los Alamos; major improvements in the theory and technology of high-intensity high-brightness accelerators fostered by the SDIO Neutral Particle Beam program; and development of high-power continuous-wave (cw) radio-frequency (rf) generators for high-energy colliding-beam rings. The reference ATW accelerator concept described in this paper is based on room-temperature copper accelerating cavities. Advances in superconducting niobium cavity technology have opened the possibility of application to ATW-type linacs. Useful efficiency gains could be realized, especially for lower current systems, and there may be technical advantages as well. Technology issues that need to be addressed for superconducting rf linac designs include the development of high-power rf couplers, appropriate cavity designs, and superconducting focusing elements, as well as concerns about beam damage of niobium structures and dynamic rf control with high beam currents.

Lawrence, G.P. (Los Alamos National Lab., NM (United States))

1993-01-01T23:59:59.000Z

96

Proceedings of the conference on computer codes and the linear accelerator community  

SciTech Connect

The conference whose proceedings you are reading was envisioned as the second in a series, the first having been held in San Diego in January 1988. The intended participants were those people who are actively involved in writing and applying computer codes for the solution of problems related to the design and construction of linear accelerators. The first conference reviewed many of the codes both extant and under development. This second conference provided an opportunity to update the status of those codes, and to provide a forum in which emerging new 3D codes could be described and discussed. The afternoon poster session on the second day of the conference provided an opportunity for extended discussion. All in all, this conference was felt to be quite a useful interchange of ideas and developments in the field of 3D calculations, parallel computation, higher-order optics calculations, and code documentation and maintenance for the linear accelerator community. A third conference is planned.

Cooper, R.K. (comp.)

1990-07-01T23:59:59.000Z

97

Towards radiation pressure acceleration of protons using linearly polarized ultrashort petawatt laser pulses  

E-Print Network (OSTI)

Particle acceleration using ultraintense, ultrashort laser pulses is one of the most attractive topics in relativistic laser-plasma research. We report proton/ion acceleration in the intensity range of 5x1019 W/cm2 to 3.3x1020 W/cm2 by irradiating linearly polarized, 30-fs, 1-PW laser pulses on 10- to 100-nm-thick polymer targets. The proton energy scaling with respect to the intensity and target thickness was examined. The experiments demonstrated, for the first time with linearly polarized light, a transition from the target normal sheath acceleration to radiation pressure acceleration and showed a maximum proton energy of 45 MeV when a 10-nm-thick target was irradiated by a laser intensity of 3.3x1020 W/cm2. The experimental results were further supported by two- and three-dimensional particle-in-cell simulations. Based on the deduced proton energy scaling, proton beams having an energy of ~ 200 MeV should be feasible at a laser intensity of 1.5x1021 W/cm2.

Kim, I Jong; Kim, Chul Min; Kim, Hyung Taek; Sung, Jae Hee; Lee, Seong Ku; Yu, Tae Jun; Choi, Il Woo; Lee, Chang-Lyoul; Nam, Kee Hwan; Nickles, Peter V; Jeong, Tae Moon; Lee, Jongmin

2013-01-01T23:59:59.000Z

98

Beam loading voltage profile of an accelerating section with a linearly varying group velocity  

E-Print Network (OSTI)

The CLIC Tapered Damped accelerating Structure (TDS) has a 5.4% detuning of the lowest dipole mode. The geometrical variations that produce this detuning range also fix the fundamental mode's group velocity variation - very nearly linear with 0.108c (c is the speed of light) at the structure input to 0.054c at the output. In addition R'/Q also varies approximately linearly, from 22.3 kW/m at the input to 30 kW/m at the output. These variations result in a structure that is neither constant impedance nor constant gradient so the widely used relationships between structure length, input and average accelerating gradient are not applicable. In order to simplify the process of optimizing accelerator parameters an analytic expression for the voltage profile in a structure with a linearly varying group velocity has been derived. A more accurate numerical solution that includes the variation in R'/Q is also presented.

Wuensch, Walter

1999-01-01T23:59:59.000Z

99

Beam loading compensation of traveling wave linacs through the time dependence of the rf drive  

SciTech Connect

Beam loading in traveling-wave linear accelerating structures leads to unacceptable spread of particle energies across an extended train of bunched particles due to beam-induced field and dispersion. Methods for modulating the rf power driving linacs are effective at reducing energy spread, but for general linacs do not have a clear analytic foundation. We report here methods for calculating how to modulate the rf drive in arbitrarily nonuniform traveling-wave linacs within the convective-transport (power-diffusion) model that results in no additional energy spread due to beam loading (but not dispersion). Varying group velocity, loss factor, and cell quality factor within a structure, and nonzero particle velocity, are handled.

Towne N.; Rose J.

2011-09-30T23:59:59.000Z

100

SLAC Linac RF Performance for LCLS *  

E-Print Network (OSTI)

The Linac Coherent Light Source (LCLS) project at SLAC uses a dense 15 GeV electron beam passing through a long undulator to generate extremely bright x-rays at 1.5 angstroms. The project requires electron bunches with a nominal peak current of 3.5kA and bunch lengths of 0.020mm (70fs). The bunch compression techniques used to achieve the high brightness impose challenging tolerances on the accelerator RF phase and amplitude. The results of measurements on the existing SLAC linac RF phase and amplitude stability are summarised and improvements needed to meet the LCLS tolerances are discussed. 1 LCLS RF REQUIREMENTS LCLS requires the SLAC linac to perform with tolerances on RF phase and amplitude stability which are beyond all previous requirements. The LCLS is divided into four linacs L0, L1, L2, and L3 [1]. The phase and amplitude tolerances for the four linacs operated at S-

unknown authors

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Upgrading the Data Acquisition and Control System of the LANSCE LINAC  

SciTech Connect

Los Alamos National Laboratory LANL is in the process of upgrading the control system for the Los Alamos Neutron Science Center (LANSCE) linear accelerator. The 38 year-old data acquisition and control equipment is being replaced with COTS hardware. An overview of the current system requirements and how the National Instruments cRIO system meets these requirements will be given, as well as an update on the installation and operation of a prototype system in the LANSCE LINAC.

Baros, Dolores [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

102

An “NLC-Style ” Short Bunch Length Compressor in the SLAC Linac*  

E-Print Network (OSTI)

Experimental tests of a “second bunch length compressor” in a linac is important for the next generation of linear colliders and for other future accelerators. These future accelerators need bunches with lengths of order 0.06- 0.2 mni. At these lengths, new accelerator dynamics will be encountered. We have studied the possibility of constructing a second compressor with the present SLAC linac and have found a reasonable design’. The core of this project is to recontigure an old beamline (BL-90) at the 1OOOm location in the linac to: (1) extract a 10 GeV bunch, (2) pass it through a new 96 m long transport line in which length compression is done, and (3) reinject the beam into the main linac in an available drift section. Using the resulting compressed bunch, accelerator physics tests would be performed in the remaining downstream linac with the resulting very high charge density. The bunch compression in this transport line results Erom ExWiq BASlWBL90 aipor the TRANSPORT element R56 as determined from the optics of the transport line. AZ = R56 AEJE. For example, if AZ =.-0.5 mm, AIYE = OS%, R56 =-0.1 m, a bunch of 5 x lOlo particles would have a final length (03 of about 0.08 mm with apeakcurrentof96OOA. II. Decription of the Project This project would use as much existing SLAC equipment as possible: including the SLC accelerator complex, old SPEAR injection line magnets, spare power supplies and diagnostics. No civil construction is required. The design is aimed at a rapid construction and installation schedule, maintaining flexibility and with no operational impact on other SLAC programs: SLC, FFTB, or B-Factory. A schematic layout of the bunch compressor is shown in Fig. 1. The basic beam parameters are listed in Table 1. The

John T. Seeman; John T. Seeman

1993-01-01T23:59:59.000Z

103

SNS LINAC MODULATOR OPERATIONAL HISTORY AND PERFOMANCE  

Science Conference Proceedings (OSTI)

Fourteen High Voltage Converter Modulators (HVCM) were initially installed at the Spallation Neutron Source Linear Accelerator (SNS Linac) at the Oak Ridge National Laboratory in 2005. A fifteenth HVCM was added in 2009. Each modulator provides a pulse of up to 140 kV at a maximum width of 1.35 msec. Peak power level is 11 MW with an 8% duty factor. The HVCM system must be available for neutron production (NP) 24/7 with the exception being two, 6-week maintenance periods per year. HVCM reliability is one of the most important factors to maximize Linac availability and achieve SNS performance goals. During the last few years several modifications have been implemented to improve the overall system reliability. This paper presents operational history of the HVCM systems and examines failure mode statistical data since the modulators began operating at 60 Hz. System enhancements and upgrades aimed at providing long term reliable operation with minimal down time are also discussed in the paper.

Peplov, Vladimir V [ORNL; Anderson, David E [ORNL; Cutler, Roy I [ORNL; Hicks, Jim [ORNL; Saethre, Robert B [ORNL; Wezensky, Mark W [ORNL

2011-01-01T23:59:59.000Z

104

Assessing Risk in Costing High-energy Accelerators: from Existing Projects to the Future Linear Collider  

E-Print Network (OSTI)

High-energy accelerators are large projects funded by public money, developed over the years and constructed via major industrial contracts both in advanced technology and in more conventional domains such as civil engineering and infrastructure, for which they often constitute one-of markets. Assessing their cost, as well as the risk and uncertainty associated with this assessment is therefore an essential part of project preparation and a justified requirement by the funding agencies. Stemming from the experience with large circular colliders at CERN, LEP and LHC, as well as with the Main Injector, the Tevatron Collider Experiments and Accelerator Upgrades, and the NOvA Experiment at Fermilab, we discuss sources of cost variance and derive cost risk assessment methods applicable to the future linear collider, through its two technical approaches for ILC and CLIC. We also address disparities in cost risk assessment imposed by regional differences in regulations, procedures and practices.

Lebrun, Philippe

2010-01-01T23:59:59.000Z

105

Accelerator technology for the Los Alamos ATW (accelerator transmutation of nuclear waste) system  

SciTech Connect

The Los Alamos concept for accelerator transmutation of nuclear waste (ATW) employs a high-power proton linear accelerator to generate intense fluxes of thermal neutrons (>10{sup 16} n/cm{sup 2}-s) through spallation on a lead-bismuth target. The nominal beam energy for an ATW accelerator is 1.6 GeV, with average current requirements ranging from 250 mA to 30 mA, depending on application specifics. A recent study of accelerator production of tritium (APT) led to the development of a detailed point design for a 1.6 GeV, 250 mA cw proton linac. The accelerator design was reviewed by the Energy Research Advisory Board (ERAB) and found to be technically sound. The Panel concluded that linac of this power level could now be implemented within the existing technology base, given an adequate component development program and an integrated engineering demonstration of the front end.

Lawrence, G.P.

1991-01-01T23:59:59.000Z

106

Visual Outcome in Meningiomas Around Anterior Visual Pathways Treated With Linear Accelerator Fractionated Stereotactic Radiotherapy  

SciTech Connect

Purpose: Meningiomas threatening the anterior visual pathways (AVPs) and not amenable for surgery are currently treated with multisession stereotactic radiotherapy. Stereotactic radiotherapy is available with a number of devices. The most ubiquitous include the gamma knife, CyberKnife, tomotherapy, and isocentric linear accelerator systems. The purpose of our study was to describe a case series of AVP meningiomas treated with linear accelerator fractionated stereotactic radiotherapy (FSRT) using the multiple, noncoplanar, dynamic conformal rotation paradigm and to compare the success and complication rates with those reported for other techniques. Patients and Methods: We included all patients with AVP meningiomas followed up at our neuro-ophthalmology unit for a minimum of 12 months after FSRT. We compared the details of the neuro-ophthalmologic examinations and tumor size before and after FSRT and at the end of follow-up. Results: Of 87 patients with AVP meningiomas, 17 had been referred for FSRT. Of the 17 patients, 16 completed >12 months of follow-up (mean 39). Of the 16 patients, 11 had undergone surgery before FSRT and 5 had undergone FSRT as first-line management. Tumor control was achieved in 14 of the 16 patients, with three meningiomas shrinking in size after RT. Two meningiomas progressed, one in an area that was outside the radiation field. The visual function had improved in 6 or stabilized in 8 of the 16 patients (88%) and worsened in 2 (12%). Conclusions: Linear accelerator fractionated RT using the multiple noncoplanar dynamic rotation conformal paradigm can be offered to patients with meningiomas that threaten the anterior visual pathways as an adjunct to surgery or as first-line treatment, with results comparable to those reported for other stereotactic RT techniques.

Stiebel-Kalish, Hadas, E-mail: kalishhadas@gmail.com [Neuro-Ophthalmology Unit, Rabin Medical Center, Petah Tikva (Israel); Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Reich, Ehud [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Department of Ophthalmology, Rabin Medical Center, Petah Tikva (Israel); Gal, Lior [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Rappaport, Zvi Harry [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Department of Neurosurgery, Rabin Medical Center, Petah Tikva (Israel); Nissim, Ouzi [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Department of Neurosurgery, Sheba Medical Center, Ramat Gan (Israel); Pfeffer, Raphael [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Spiegelmann, Roberto [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Department of Neurosurgery, Sheba Medical Center, Ramat Gan (Israel)

2012-02-01T23:59:59.000Z

107

Measurements of Neutron Induced Cross Sections at the Oak Ridge Electron Linear Accelerator  

SciTech Connect

We have used the Oak Ridge Electron Linear Accelerator (ORELA) to measure neutron total and the fission cross sections of 233U in the energy range from 0.36 eV to ~700 keV. We report average fission and total cross sections. Also, we measured the neutron total cross sections of 27Al and Natural chlorine as well as the capture cross section of Al over an energy range from 100 eV up to about 400 keV.

Guber, K.H.; Harvey, J.A.; Hill, N.W.; Koehler, P.E.; Leal, L.C.; Sayer, R.O.; Spencer, R.R.

1999-09-20T23:59:59.000Z

108

Measurements of Neutron Induced Cross Sections at the Oak Ridge Electron Linear Accelerator  

Science Conference Proceedings (OSTI)

We have used the Oak Ridge Electron Linear Accelerator (ORELA) to measure neutron total and the fission cross sections of 233U in the energy range from 0.36 eV to ~700 keV. We report average fission and total cross sections. Also, we measured the neutron total cross sections of 27Al and Natural chlorine as well as the capture cross section of Al over an energy range from 100 eV up to about 400 keV.

Guber, K.H.; Harvey, J.A.; Hill, N.W.; Koehler, P.E.; Leal, L.C.; Sayer, R.O.; Spencer, R.R.

1999-09-20T23:59:59.000Z

109

RF System Upgrades to the Advanced Photon Source Linear Accelerator in Support of the Fel Operation  

E-Print Network (OSTI)

The S-band linear accelerator, which was built to be the source of particles and the front end of the Advanced Photon Source injector, is now also being used to support a low-energy undulator test line (LEUTL) and to drive a free-electron laser (FEL). The more severe rf stability requirements of the FEL have resulted in an effort to identify sources of phase and amplitude instability and implement corresponding upgrades to the rf generation chain and the measurement system. Test data and improvements implemented and planned are described

Smith, T L; Grelick, A E; Pile, G; Nassiri, A; Arnold, N

2000-01-01T23:59:59.000Z

110

Report of the ICFA Beam Dynamics Workshop 'Accelerators for a Higgs Factory: Linear vs. Circular' (HF2012)  

E-Print Network (OSTI)

This paper is a summary report of the ICFA Beam Dynamics Workshop 'Accelerators for a Higgs Factory: Linear vs. Circular' (HF2012). It discusses four types of accelerators as possible candidates for a Higgs factory: linear e+e- colliders, circular e+e- colliders, muon collider and photon colliders. The comparison includes: physics reach, performance (energy and luminosity), upgrade potential, technology maturity and readiness, and technical challenges requiring further R&D.

Alain Blondel; Alex Chao; Weiren Chou; Jie Gao; Daniel Schulte; Kaoru Yokoya

2013-02-14T23:59:59.000Z

111

Pulse power linac  

DOE Patents (OSTI)

A linear acceleration for charged particles is constructed of a plurality of transmission line sections that extend between a power injection region and an accelerating region. Each line section is constructed of spaced plate-like conductors and is coupled to an accelerating gap located at the accelerating region. Each gap is formed between a pair of apertured electrodes, with all of the electrode apertures being aligned along a particle accelerating path. The accelerating gaps are arranged in series, and at the injection region the line sections are connected in parallel. At the injection region a power pulse is applied simultaneously to all line sections. The line sections are graduated in length so that the pulse reaches the gaps in a coordinated sequence whereby pulse energy is applied to particles as they reach each of the gaps along the accelerating path.

Villa, Francesco (Alameda, CA)

1990-01-01T23:59:59.000Z

112

Stanford Linear Accelerator Center, Order R2-2005-0022, May 18, 2005  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD SAN FRANCISCO BAY REGION ORDER No. R2-2005-0022 RESCISSION of: ORDER No. 85-88, WASTE DISCHARGE REQUIREMENTS and ADOPTION of: SITE CLEANUP REQUIREMENTS for: STANFORD UNIVERSITY and the UNITED STATES DEPARTMENT OF ENERGY for the property located at the: STANFORD LINEAR ACCELERATOR CENTER 2575 SAND HILL ROAD MENLO PARK, SAN MATEO COUNTY FINDINGS: The California Regional Water Quality Control Board, San Francisco Bay Region (Water Board) finds that: 1. Purpose of Order This Order establishes Site Cleanup Requirements for the investigation and remediation of impacted soil and groundwater resulting from historical spills and leaks that have occurred during the course of operations of the Stanford Linear

113

Second order particle motion equations and linear chromaticity calculation in accelerator rings  

SciTech Connect

The first part of this note presents a thorough study on the second order particle motion equations, both in continuous field and in hard edges, with emphasis put on the latter. Having quite general conditions and strict mathematical treatments, it provides a sound ground from which many problems can be solved without fear of being misled. Then the linear CHR calculation is inspected, the first step being a general analytical expression of the transverse oscillation phase increment due to a small disturbance. The expression for the CHR is then readily obtained since tune is the transverse oscillation number per turn and the CHR is the linear dependence of the tune on particle energy/momentum deviation. The last part gives the formulae for practical CHR calculation, which are general enough to include almost all the magnet types commonly used in various accelerator rings and are simpler than can be found elsewhere.

Liu, R.Z.

1984-01-01T23:59:59.000Z

114

Chromaticity of the lattice and beam stability in energy-recovery linacs  

Science Conference Proceedings (OSTI)

Energy recovery linacs (ERLs) are an emerging generation of accelerators promising to revolutionize the fields of high-energy physics and photon sciences. These accelerators combine the advantages of linear accelerators with that of storage rings, and hold the promise of delivering electron beams of unprecedented power and quality. Use of superconducting radio-frequency (SRF) cavities converts ERLs into nearly perfect 'perpetuum mobile' accelerators, wherein the beam is accelerated to a desirable energy, used, and then gives the energy back to the RF field. One potential weakness of these devices is transverse beam break-up instability that could severely limit the available beam current. In this paper, I present a method of suppressing these dangerous effects using a natural phenomenon in the accelerators, viz., the chromaticity of the transverse motion.

Litvinenko, V.N.

2011-12-23T23:59:59.000Z

115

Automated Operation of the APS LINAC using the Procedure Execution Manager  

E-Print Network (OSTI)

The Advanced Photon Source (APS) linear accelerator has two thermionic cathode rf guns and one photocathode rf gun. The thermionic guns are used primarily for APS operations while the photocathode gun is used as a free-electron laser (FEL) driver. With each gun requiring a different lattice and timing configuration, the need to change quickly between guns puts great demands on the accelerator operators. Using the Procedure Execution Manager (PEM), a software environment for managing automated procedures, we have made start-up and switch-over of the linac systems both easier and more reliable. The PEM is a graphical user interface written in Tcl/Tk that permits the user to invoke "machine procedures" and control their execution. It allows construction of procedures in a hierarchical, parallel fashion, which makes for efficient execution and development. In this paper, we discuss the features and advantages of the PEM environment as well the specifics of our procedures for the APS linac.

Soliday, R; Borland, M

2000-01-01T23:59:59.000Z

116

Coupled-cavity drift-tube linac  

DOE Patents (OSTI)

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 free-space wavelength of the resonant mode. Adjacent accelerating cavities have oppositely directed electric fields, alternating in phase by 180 degrees. The chain of cavities operates in a .pi./2 structure mode so the coupling cavities are nominally unexcited. The CCDTL configuration provides an rf structure with high shunt impedance for intermediate velocity charged particles, i.e., particles with energies in the 20-200 MeV range.

Billen, James H. (Los Alamos, NM)

1996-01-01T23:59:59.000Z

117

Linac Coherent Light Source Video and Multimedia Collection  

DOE Data Explorer (OSTI)

The Linac Coherent Light Source (LCLS), a DOE Scientific User Facility, began operation in 2009. SLAC's two-mile-long linear accelerator (linac) has long produced high-energy electrons for physics experiments. Now the linac is driving a new kind of laser, creating X-ray pulses more than a billion times brighter than the most powerful existing sources. Intense x-ray beams are not new. However, atoms are constantly moving or vibrating, and synchrotron X-ray sources produce long pulses which yield only blurred images of these motions. LCLS is the first source to produce X-rays that are both very intense and clumped into ultrafast pulses. By sequencing together images of the ultrasmall, taken with the ultrafast pulses of the LCLS, scientists are for the first time creating molecular movies, revealing the frenetic action of the atomic world for us to see. [Extracted, with edits, from http://lcls.slac.stanford.edu/WhatIsLCLS_1.aspx] The LCLS Multimedia gallery currently includes four short videos about the science and several clips that provide animated tours or flyovers of the facility and its instruments. Podcasts are an opportunity to hear key staff members address details of LCLS operations, and blog entries from five team members provide behind-the-scenes glimpses of this physics adventure.

118

Intraoperative radiation therapy using mobile electron linear accelerators: Report of AAPM Radiation Therapy Committee Task Group No. 72  

Science Conference Proceedings (OSTI)

Intraoperative radiation therapy (IORT) has been customarily performed either in a shielded operating suite located in the operating room (OR) or in a shielded treatment room located within the Department of Radiation Oncology. In both cases, this cancer treatment modality uses stationary linear accelerators. With the development of new technology, mobile linear accelerators have recently become available for IORT. Mobility offers flexibility in treatment location and is leading to a renewed interest in IORT. These mobile accelerator units, which can be transported any day of use to almost any location within a hospital setting, are assembled in a nondedicated environment and used to deliver IORT. Numerous aspects of the design of these new units differ from that of conventional linear accelerators. The scope of this Task Group (TG-72) will focus on items that particularly apply to mobile IORT electron systems. More specifically, the charges to this Task Group are to (i) identify the key differences between stationary and mobile electron linear accelerators used for IORT (ii) describe and recommend the implementation of an IORT program within the OR environment, (iii) present and discuss radiation protection issues and consequences of working within a nondedicated radiotherapy environment, (iv) describe and recommend the acceptance and machine commissioning of items that are specific to mobile electron linear accelerators, and (v) design and recommend an efficient quality assurance program for mobile systems.

Sam Beddar, A.; Biggs, Peter J.; Chang Sha; Ezzell, Gary A.; Faddegon, Bruce A.; Hensley, Frank W.; Mills, Michael D. [Department of Radiation Physics, Division of Radiation Oncology, Unit 94, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030 (United States); Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599 (United States); Department of Radiation Oncology, Mayo Clinic Scottsdale, Scottsdale, Arizona 85259 (United States); Department of Radiation Oncology, University of California San Francisco, San Francisco, California 94143 (United States); Department of Radiation Oncology, University of Heidelberg, 69120 Heidelberg (Germany); Department of Radiation Oncology, James Graham Brown Cancer Center, Louisville, Kentucky 40202 (United States)

2006-05-15T23:59:59.000Z

119

Experimental measurement methods and data on irradiation of functional design materials by helium ions in linear accelerator  

E-Print Network (OSTI)

The experimental research on the irradiation of the functional design materials by the Helium ions in the linear accelerator is conducted. The experimental measurements techniques and data on the irradiation of the functional design materials by the Helium ions with the energy up to 4 MeV, including the detailed scheme of experimental measurements setup, are presented. The new design of accelerating structure of the IH-type such as POS-4, using the method of alternate-phase focusing with the step-by-step change of the synchronous phase along the focusing periods in a linear accelerator, is developed with the aim to irradiate the functional design materials by the Helium ions. The new design of the injector of the charged Helium ions with the energy of 120 KeV at the output of an accelerating tube and the accelerating structure of the type of POS-4 for the one time charged Helium ions acceleration in the linear accelerator are researched and developed. The special chamber for the irradiation of functional design materials by the Helium ions is also created. In the process of experiment, the temperature of a sample, the magnitude of current of Helium ions beam and the irradiation dose of sample are measured precisely. The experimental measurement setup and techniques are fully tested and optimized in the course of the research on the electro-physical properties of irradiated samples and the thermal-desorption of Helium ions in a wide range of temperatures

R. A. Anokhin; V. N. Voyevodin; S. N. Dubnyuk; A. M. Egorov; B. V. Zaitsev; A. F. Kobets; O. P. Ledenyov; K. V. Pavliy; V. V. Ruzhitsky; G. D. Tolstolutskaya

2013-09-03T23:59:59.000Z

120

Neutron source, linear-accelerator fuel enricher and regenerator and associated methods  

DOE Patents (OSTI)

A device for producing fissile material inside of fabricated nuclear elements so that they can be used to produce power in nuclear power reactors. Fuel elements, for example, of a LWR are placed in pressure tubes in a vessel surrounding a liquid lead-bismuth flowing columnar target. A linear-accelerator proton beam enters the side of the vessel and impinges on the dispersed liquid lead-bismuth columns and produces neutrons which radiate through the surrounding pressure tube assembly or blanket containing the nuclear fuel elements. These neutrons are absorbed by the natural fertile uranium-238 elements and are transformed to fissile plutonium-239. The fertile fuel is thus enriched in fissile material to a concentration whereby they can be used in power reactors. After use in the power reactors, dispensed depleted fuel elements can be reinserted into the pressure tubes surrounding the target and the nuclear fuel regenerated for further burning in the power reactor.

Steinberg, Meyer (Huntington Station, NY); Powell, James R. (Shoreham, NY); Takahashi, Hiroshi (Setauket, NY); Grand, Pierre (Blue Point, NY); Kouts, Herbert (Brookhaven, NY)

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Load Schedule Coordination for a Large Linear Accelerator: An Operation Powerplay Concept  

E-Print Network (OSTI)

Operation Powerplay is a viable electric load management program developed and tested with Department of Energy funding and support. It is a concept designed to provide financial benefits to a utility and one or more of its customers through priority-based or on-demand load shaving. Currently being implemented in pilot form is a variation of Operation Powerplay. In this instance, it is the mutual cooperation between the Western Area Power Administration (Western), which markets hydro-power from Federal power projects, and the Los Alamos National Laboratory (LANL) at Los Alamos, New Mexico. With this variation, only the portion of LANL's total load requirement for the Linear Accelerator at the Meson Physics Facility is targeted to be managed by this arrangement. This paper will discuss the negotiations and agreements between LANL and Western to maximize use of the Meson facility and minimize operational costs through this variation of Operation Powerplay.

Johnson, W. H.

1984-01-01T23:59:59.000Z

122

The Fast Lane: Fermilab's Accelerators  

NLE Websites -- All DOE Office Websites (Extended Search)

Lane: Accelerators at Fermilab Introduction Introduction to Accelerators Accelerator Chain Cockcroft-Walton How it works How it looks Linac How it works How it looks Booster How it...

123

Beam Dynamics Study of X-Band Linac Driven X-Ray FELS  

Science Conference Proceedings (OSTI)

Several linac driven X-ray Free Electron Lasers (XFELs) are being developed to provide high brightness photon beams with very short, tunable wavelengths. In this paper, three XFEL configurations are proposed that achieve LCLS-like performance using X-band linac drivers. These linacs are more versatile, efficient and compact than ones using S-band or C-band rf technology. For each of the designs, the overall accelerator layout and the shaping of the bunch longitudinal phase space are described briefly. During the last 40 years, the photon wavelengths from linac driven FELs have been pushed shorter by increasing the electron beam energy and adopting shorter period undulators. Recently, the wavelengths have reached the X-ray range, with FLASH (Free-Electron Laser in Hamburg) and LCLS (Linac Coherent Light Source) successfully providing users with soft and hard X-rays, respectively. FLASH uses a 1.2 GeV L-band (1.3 GHz) superconducting linac driver and can deliver 10-70 fs FWHM long photon pulses in a wavelength range of 44 nm to 4.1 nm. LCLS uses the last third of the SLAC 3 km S-band (2.856 GHz) normal-conducting linac to produce 3.5 GeV to 15 GeV bunches to generate soft and hard X-rays with good spatial coherence at wavelengths from 2.2 nm to 0.12 nm. Newer XFELs (at Spring8 and PSI) use C-band (5.7 GHz) normal-conducting linac drivers, which can sustain higher acceleration gradients, and hence shorten the linac length, and are more efficient at converting rf energy to bunch energy. The X-band (11.4 GHz) rf technology developed for NLC/GLC offers even higher gradients and efficiencies, and the shorter rf wavelength allows more versatility in longitudinal bunch phase space compression and manipulation. In the following sections, three different configurations of X-band linac driven XFELs are described that operate from 6 to 14 GeV. The first (LOW CHARGE DESIGN) has an electron bunch charge of only 10 pC; the second (OPTICS LINEARIZATION DESIGN) is based on optics linearization of the longitudinal phase space in the first stage bunch compressor and can operate with either a high (250 pC) or low (20 pC) bunch charge; and the third (LCLS INJECTOR DESIGN) is similar to LCLS but uses an X-band linac after the first stage bunch compressor at 250 MeV to achieve a final beam energy up to 14 GeV. Compared with LCLS, these X-band linacs are at least a factor of three shorter.

Adolphsen, C.; Limborg-Deprey, C.; Raubenheimer, T.O.; Wu, J.; /SLAC; Sun, Y.; /SLAC

2011-12-13T23:59:59.000Z

124

New Post-Linac Collimation System  

NLE Websites -- All DOE Office Websites (Extended Search)

Post-Linac Post-Linac Collimation System for the Next Linear Collider NLC Post-Linac Collimation Task Force LCC-Note-0052 21-Feb-2001 Abstract We present a new design for the NLC post-linac collimation system. The new design sepa- rates the collimation of off-energy particles and particles with large betatron amplitudes. The energy collimation system achieves passive protection against damage by an errant bunch train via large horizontal dispersion and vertical betatron functions, and makes use of optical symme- tries to reduce jitter amplification. The betatron collimation system permits infrequent damage to the thin "spoiler" collimators, while the thick "absorber" collimators have a much larger aperture and are thus more difficult to hit. The physical phenomena which are relevant to the design and operation of the collimation system are reviewed, and

125

Linac Coherent Light Source Overview | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Linac Coherent Light Source Overview Linac Coherent Light Source Overview Linac Coherent Light Source Overview Addthis Description Take an animated tour of the Linac Coherent Light Source (LCLS). Follow the laser pulse from the injector gun all the way through to the Far Experimental Hall. Duration 5:50 Topic Physics Credit Energy Department Video MR. : The SLAC National Accelerator Laboratory is located in the heart of California's beautiful San Francisco Bay Area. Operated by Stanford University for the U.S. Department of Energy, SLAC has been home to the world's longest particle accelerator for nearly 50 years. In 2009 SLAC ushered in a new era in its long history of physics research with a new kind of laser called the Linac Coherent Light Source, or LCLS. The LCLS is the first laser in the world to produce hard X-rays, which can

126

Accelerators  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerators Elementary Particles Detectors Accelerators Visit World Labs For Children - for younger people For Children The Electric Force For Children Electric Force Fields For...

127

Medical Isotope Production Using A 60 MeV Linear Electron Accelerator , R.C. Block1  

E-Print Network (OSTI)

Medical Isotope Production Using A 60 MeV Linear Electron Accelerator Y. Danon1 , R.C. Block1 , R@rpi.edu) 2 AlphaMed Inc, 20 Juniper Ridge Road, Acton, MA 01720 INTRODUCTION Medical isotopes can be produced

Danon, Yaron

128

Feasibility of producing a short, high energy s-band linear accelerator using a klystron power source  

SciTech Connect

Purpose: To use a finite-element method (FEM) model to study the feasibility of producing a short s-band (2.9985 GHz) waveguide capable of producing x-rays energies up to 10 MV, for applications in a linac-MR, as well as conventional radiotherapy. Methods: An existing waveguide FEM model developed by the authors' group is used to simulate replacing the magnetron power source with a klystron. Peak fields within the waveguide are compared with a published experimental threshold for electric breakdown. The RF fields in the first accelerating cavity are scaled, approximating the effect of modifications to the first coupling cavity. Electron trajectories are calculated within the RF fields, and the energy spectrum, beam current, and focal spot of the electron beam are analyzed. One electron spectrum is selected for Monte Carlo simulations and the resulting PDD compared to measurement. Results: When the first cavity fields are scaled by a factor of 0.475, the peak magnitude of the electric fields within the waveguide are calculated to be 223.1 MV/m, 29% lower than the published threshold for breakdown at this operating frequency. Maximum electron energy increased from 6.2 to 10.4 MeV, and beam current increased from 134 to 170 mA. The focal spot FWHM is decreased slightly from 0.07 to 0.05 mm, and the width of the energy spectrum increased slightly from 0.44 to 0.70 MeV. Monte Carlo results show d{sub max} is at 2.15 cm for a 10 Multiplication-Sign 10 cm{sup 2} field, compared with 2.3 cm for a Varian 10 MV linac, while the penumbral widths are 4.8 and 5.6 mm, respectively. Conclusions: The authors' simulation results show that a short, high-energy, s-band accelerator is feasible and electric breakdown is not expected to interfere with operation at these field strengths. With minor modifications to the first coupling cavity, all electron beam parameters are improved.

Baillie, Devin [Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Aubin, J. St. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Fallone, B. G. [Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Steciw, S. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

2013-04-15T23:59:59.000Z

129

Physics considerations for laser-plasma linear colliders  

SciTech Connect

Physics considerations for a next-generation linear collider based on laser-plasma accelerators are discussed. The ultra-high accelerating gradient of a laser-plasma accelerator and short laser coupling distance between accelerator stages allows for a compact linac. Two regimes of laser-plasma acceleration are discussed. The highly nonlinear regime has the advantages of higher accelerating fields and uniform focusing forces, whereas the quasi-linear regime has the advantage of symmetric accelerating properties for electrons and positrons. Scaling of various accelerator and collider parameters with respect to plasma density and laser wavelength are derived. Reduction of beamstrahlung effects implies the use of ultra-short bunches of moderate charge. The total linac length scales inversely with the square root of the plasma density, whereas the total power scales proportional to the square root of the density. A 1 TeV center-of-mass collider based on stages using a plasma density of 10{sup 17} cm{sup -3} requires tens of J of laser energy per stage (using 1 {micro}m wavelength lasers) with tens of kHz repetition rate. Coulomb scattering and synchrotron radiation are examined and found not to significantly degrade beam quality. A photon collider based on laser-plasma accelerated beams is also considered. The requirements for the scattering laser energy are comparable to those of a single laser-plasma accelerator stage.

Schroeder, Carl; Esarey, Eric; Geddes, Cameron; Benedetti, Carlo; Leemans, Wim

2010-06-11T23:59:59.000Z

130

Accelerator technology for the LANL ATW system  

Science Conference Proceedings (OSTI)

The Los Alamos National Laboratory concept for accelerator transmutation of nuclear waste (ATW) employs a high-power proton linear accelerator to generate intense fluxes of thermal neutrons (> 10{sup 16} n/cm{sup 20} {center dot} s) through spallation on a lead-bismuth target. The nominal beam energy for a ATW accelerator is 1.6 GeV, and the average current requirements range from 250 to 30 mA, depending on application specifics. A recent study of accelerator production of tritium (APT) led to the development of a detailed point design for a 1.6-GeV, 250-mA cw proton linac. The accelerator design was reviewed by the Energy Research Advisory Board and found to be technically sound. The panel concluded that a linac of this power level could now be implemented within the existing technology base, given an adequate component development program and an integrated engineering demonstration of the front end. The APT linac can be taken as representing the upper bound of ATW power requirements.

Lawrence, G.P. (Los Alamos National Lab., NM (United States))

1991-01-01T23:59:59.000Z

131

EBIS as an injector for heavy-ion linacs  

SciTech Connect

The Electron Beam Ion Source (EBIS), because of its high-charge states and pulsed operation, is ideally suited as an injector for a heavy-ion linac operating at a low duty factor. Although presently in use with conventional linacs, the low emittance and the large yield of highly charged ions in each pulse make the EBIS even more interesting as an injector for the new linac accelerating structures such as the alternating-phase-focusing (APF) structure or the radio-frequency quadrupole (RFQ) structure. These new structures could be used with an EBIS to produce a small, efficient, low-duty-cycle accelerator. Coupled to a conventional linac, the resulting accelerator could be used for heavy-ion medical therapy or nuclear physics, or it could be used as an injector for a synchrotron or storage ring.

Hamm, R.W.

1979-01-01T23:59:59.000Z

132

Magnet innovations for linacs  

Science Conference Proceedings (OSTI)

It is possible to produce large magnetic fields at the aperture of permanent magnet quadrupoles, even when the magnetic aperture is very small. That, combined with their compactness, makes permanent magnet quadrupoles very powerful components of small aperture linacs. Results will be presented about past and present work on both fixed and variable strength permanent magnets suitable for use in and around linacs.

Halbach, K.

1986-06-01T23:59:59.000Z

133

Induction Linac Pulsers  

DOE Green Energy (OSTI)

The pulsers used in most of the induction linacs evolved from the very large body of work that was done in the U.S. and Great Britain during the development of the pulsed magnetron for radar. The radar modulators started at {approx}100 kW and reached >10 MW by 1945. A typical pulse length was 1 {mu}s at a repetition rate of 1,000 pps. A very comprehensive account of the modulator development is Pulse Generators by Lebacqz and Glasoe, one of the Radiation Laboratory Series. There are many permutations of possible modulators, two of the choices being tube type and line type. In earlier notes I wrote that technically the vacuum tube pulser met all of our induction linac needs, in the sense that a number of tubes, in series and parallel if required, could produce our pulses, regulate their voltage, be useable in feed-forward correctors, and provide a low source impedance. At a lower speed, an FET array is similar, and we have obtained and tested a large array capable of >10 MW switching. A modulator with an electronically controlled output only needs a capacitor for energy storage and in a switched mode can transfer the energy from the capacitor to the load at high efficiency. Driving a full size Astron induction core and a simulated resistive 'beam load' we achieved >50% efficiency. These electronically controlled output pulses can produce the pulses we desire but are not used because of their high cost. The second choice, the line type pulser, visually comprises a closing switch and a distributed or a lumped element transmission line. The typical switch cannot open or stop conducting after the desired pulse has been produced, and consequently all of the initially stored energy is dissipated. This approximately halves the efficiency, and the original cost estimating program LIACEP used this factor of two, even though our circuits are usually worse, and even though our inveterate optimists often omit it. The 'missing' energy is that which is reflected back into the line from mismatches, the energy left in the accelerator module's capacitance, the energy lost in the switch during switching and during the pulse, and the energy lost in the pulse line charging circuit. For example, a simple resistor-limited power supply dissipates as much energy as it delivers to the pulse forming line, giving a factor if two by itself, therefore efficiency requires a more complicated charging system.

Faltens, Andris

2011-01-07T23:59:59.000Z

134

BEAM TRANSVERSE ISSUES AT THE SNS LINAC  

Science Conference Proceedings (OSTI)

The Spallation Neutron Source (SNS) linac system is designed to deliver 1 GeV pulsed H- beams up to 1.56 MW. As beam power was increased from 10 kW to 680 kW in less than three years, beam loss in the accelerator systems C particularly in the superconducting linac (SCL), became more critical. In the previous studies, beam loss in the SCL was mainly attributed to longitudinal problems. However, our most recent simulations have focused on the transverse issues. These include multipole components from magnet imperfections and from dipole corrector windings of the SNS linac quadrupoles. The effects of these multipoles coupled with other transverse errors and a new possible cause of beam loss will be discussed.

Zhang, Yan [ORNL; Allen, Christopher K [ORNL; Holmes, Jeffrey A [ORNL; Galambos, John D [ORNL; Wang, Jian-Guang [ORNL

2010-01-01T23:59:59.000Z

135

Klystron switching power supplies for the Internation Linear Collider  

Science Conference Proceedings (OSTI)

The International Linear Collider is a majestic High Energy Physics particle accelerator that will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. ILC will complement the Large Hadron Collider (LHC), a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, by producing electron-positron collisions at center of mass energy of about 500 GeV. In particular, the subject of this dissertation is the R&D for a solid state Marx Modulator and relative switching power supply for the International Linear Collider Main LINAC Radio Frequency stations.

Fraioli, Andrea; /Cassino U. /INFN, Pisa

2009-12-01T23:59:59.000Z

136

acceleration  

NLE Websites -- All DOE Office Websites (Extended Search)

middle name. The head of Fermilab's Accelerator Division explains a basic idea of high-energy physics in everyday language. Painless Physics Articles BEAM COOLING August 2, 1996...

137

SuperHILAC: Heavy-ion linear accelerator: Summary of capabilities, facilities, operations, and research  

Science Conference Proceedings (OSTI)

This report consists of a description of the accelerator facilities and a review of research programs being conducted there. Lists of SuperHILAC researchers and publications are also given.

McDonald, R.J. (ed.)

1987-09-01T23:59:59.000Z

138

C-AD Accelerator Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerator Division Accelerator Division The Accelerator Division operates and continually upgrades a complex of eight accelerators: 2 Tandem Van de Graaff electrostatic accelerators, an Electron Beam Ion Source (EBIS), a 200 MeV proton Linac, the AGS Booster, the Alternating Gradient Synchrotron (AGS), and the 2 rings of the Relativistic Heavy Ion Collider (RHIC). These machines serve user programs at the Tandems, the Brookhaven Linac Isotope Producer (BLIP), the NASA Space Radiation Laboratory (NSRL), and the 2 RHIC experiments STAR, and PHENIX. The Division also supports the development of new accelerators and accelerator components. Contact Personnel Division Head: Wolfram Fischer Deputy Head: Joe Tuozzolo Division Secretary: Anna Petway Accelerator Physics: Michael Blaskiewicz

139

Design of a superconducting linear accelerator for an Infrared Free Electron Laser of the proposed Chemical Dynamics Research Laboratory at LBL  

Science Conference Proceedings (OSTI)

An accelerator complex has recently been designed at LBL as part of an Infrared Free Electron Laser facility in support of a proposed Chemical Dynamics Research Laboratory. We will outline the choice of parameters and design philosophy, which are strongly driven by the demand of reliable and spectrally stable operation of the FEL for very special scientific experiments. The design is based on a 500 MHz recirculating superconducting electron linac with highest energy reach of about 60 MeV. The accelerator is injected with beams prepared by a specially designed gun-buncher system and incorporates a near-isochronous and achromatic recirculation line tunable over a wide range of beam energies. The stability issues considered to arrive at the specific design will be outlined.

Chattopadhyay, S.; Byrns, R.; Donahue, R.; Edighoffer, J.; Gough, R.; Hoyer, E.; Kim, K.J.; Leemans, W.; Staples, J.; Taylor, B.; Xie, M.

1992-08-01T23:59:59.000Z

140

Accelerator  

NLE Websites -- All DOE Office Websites (Extended Search)

1. ACCELERATOR PHYSICS OF COLLIDERS Revised July 2011 by D. A. Edwards (DESY) and M. J. Syphers (MSU) 1.1. Luminosity This article provides background for the High-Energy Collider...

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

LANSCE Drift Tube Linac Water Control System Refurbishment  

Science Conference Proceedings (OSTI)

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 water control systems. The systems are about 40 years old, use outdated and non-replaceable equipment and NIM bin control modules, are beyond their design life and provide unstable temperature control. Insufficient instrumentation and documentation further complicate efforts at maintaining system performance. Detailed design of the replacement cooling systems is currently in progress. Previous design experience on the SNS accelerator water cooling systems will be leveraged, see the SNS DTL FDR. Plans call for replacement of water piping, manifolds, pumps, valves, mix tanks, instrumentation (flow, pressure and temperature) and control system hardware and software. This presentation will focus on the control system design with specific attention on planned use of the National Instruments Compact RIO platform with the Experimental Physics and Industrial Control system (EPICS) software toolkit.

Marroquin, Pilar S. [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

142

Formation of electron bunches with tailored current profiles using multi-frequency linacs  

SciTech Connect

Tailoring an electron bunch with specific current profile can provide substantial enhancement of the transformer ratio in beam-driven acceleration methods. We present a method relying on the use of a linac with accelerating sections operating at different frequencies followed by a magnetic bunch compressor. The experimental verfification of the technique in a two-frequency linac is presented. The compatibility of the proposed technique with the formation and acceleration of a drive and witness bunches is numerically demonstrated.

Piot, P.; Behrens, C.; Gerth, C.; Lemery, F.; Mihalcea, D.; Stoltz, P. [Northern Illinois Center for Accelerator and Detector Development and Department of Physics, Northern Illinois University, DeKalb, IL 60115 (United States) and Accelerator Physics Center, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85 D-22607 Hamburg (Germany); Northern Illinois Center for Accelerator and Detector Development and Department of Physics, Northern Illinois University, DeKalb, IL 60115 (United States); Tech-X Corporation, Boulder, CO 80303 (United States)

2012-12-21T23:59:59.000Z

143

Non-Linear Transmission Line (NLTL) Microwave Source Lecture Notes the United States Particle Accelerator School  

Science Conference Proceedings (OSTI)

We will quickly go through the history of the non-linear transmission lines (NLTLs). We will describe how they work, how they are modeled and how they are designed. Note that the field of high power, NLTL microwave sources is still under development, so this is just a snap shot of their current state. Topics discussed are: (1) Introduction to solitons and the KdV equation; (2) The lumped element non-linear transmission line; (3) Solution of the KdV equation; (4) Non-linear transmission lines at microwave frequencies; (5) Numerical methods for NLTL analysis; (6) Unipolar versus bipolar input; (7) High power NLTL pioneers; (8) Resistive versus reactive load; (9) Non-lineaer dielectrics; and (10) Effect of losses.

Russell, Steven J. [Los Alamos National Laboratory; Carlsten, Bruce E. [Los Alamos National Laboratory

2012-06-26T23:59:59.000Z

144

Linear Collider Collaboration Tech Notes LCC-0063  

NLE Websites -- All DOE Office Websites (Extended Search)

3 3 May 2001 Varying alpha/lambda in NLC Structures - BNS Damping and Emittance Growth G. Stupakov and Z. Li Stanford Linear Accelerator Center Stanford, CA Abstract: In this note we consider the effect of varying this iris opening in the NLC structures on the beam dynamics and the rf efficiency in the linac. Varying a/λ in NLC structures - BNS damping and emittance growth G. Stupakov and Z. Li SLAC, Stanford University, Stanford, CA 94309 In this note we consider the effect of the varying the iris opening a in the NLC structures on the beam dynamics and the RF efficiency in the linac. The most important consequence of the variation of the iris openings is the change of the longitudinal and transverse wakefields. Wake as a function of parameter a for the NLC structures has been previously calculated by K. Bane. Here we will use his

145

On-Line Measurement and Tuning of Multi-Pass Recirculation Time in the CEBAF Linacs  

E-Print Network (OSTI)

On-Line Measurement and Tuning of Multi-Pass Recirculation Time in the CEBAF Linacs Michael, USA Abstract CEBAF is a CW, recirculating electron accelerator, us- ing on-crest RF acceleration the beam to drift off-crest with respect to the accelerating fields. Figure 1: Layout of CEBAF Accelerator

146

FIRST EXPERIMENTS WITH THE RF GUN BASED INJECTOR FOR THE TESLA TEST FACILITY LINAC  

E-Print Network (OSTI)

FIRST EXPERIMENTS WITH THE RF GUN BASED INJECTOR FOR THE TESLA TEST FACILITY LINAC S. Schreiber for the TESLA Collaboration, DESY, 22603 Hamburg, Germany Abstract During 1997 and 1998 a first accelerator module was tested successfully at the TESLA Test Facility Linac (TTFL) at DESY. Eight superconducting

147

PERFORMANCE STATUS OF THE RF-GUN BASED INJECTOR OF THE TESLA TEST FACILITY LINAC  

E-Print Network (OSTI)

PERFORMANCE STATUS OF THE RF-GUN BASED INJECTOR OF THE TESLA TEST FACILITY LINAC S. SchreiberÂŁ for the TESLA Collaboration, DESY, 22603 Hamburg, Germany Abstract The TESLA Test Facility Linac (TTFL) at DESY uses two modules with 8 TESLA superconducting accelerat- ing structures each to accelerate an electron

148

Acceleration  

NLE Websites -- All DOE Office Websites (Extended Search)

Acceleration Acceleration of porous media simulations on the Cray XE6 platform Kirsten M. Fagnan, Michael Lijewski, George Pau, Nicholas J. Wright Lawrence Berkeley National Laboratory 1 Cyclotron Road Berkeley, CA 94720 May 18, 2011 1 Introduction In this paper we investigate the performance of the Porous Media with Adaptive Mesh Refinment (PMAMR) code which was developed in the Center for Computational Science and Engineering at Lawrence Berkeley National Laboratory. This code is being used to model carbon sequestration and contaminant transport as part of the Advanced Simulation Capability for Environmental Management (ASCEM) project. The goal of the ASCEM project is to better understand and quantify flow and contaminant transport behavior in complex geological systems. It will also address the long-term performance of engineered components including cementitious materials in

149

AUTOMATED OPERATION OF THE APS LINAC USING THE PROCEDURE EXECUTION MANAGER  

E-Print Network (OSTI)

The Advanced Photon Source (APS) linear accelerator has two thermionic cathode rf guns and one photocathode rf gun. The thermionic guns are used primarily for APS operations while the photocathode gun is used as a freeelectron laser (FEL) driver. With each gun requiring a different lattice and timing configuration, the need to change quickly between guns puts great demands on the accelerator operators. Using the Procedure Execution Manager (PEM), a software environment for managing automated procedures, we have made start-up and switchover of the linac systems both easier and more reliable. The PEM is a graphical user interface written in Tcl/Tk that permits the user to invoke ‘machine procedures ’ and control their execution. It allows

unknown authors

2000-01-01T23:59:59.000Z

150

Use of off-axis injection as an alternative to geometrically merging beams in an energy-recovering linac  

DOE Patents (OSTI)

A method of using off-axis particle beam injection in energy-recovering linear accelerators that increases operational efficiency while eliminating the need to merge the high energy re-circulating beam with an injected low energy beam. In this arrangement, the high energy re-circulating beam and the low energy beam are manipulated such that they are within a predetermined distance from one another and then the two immerged beams are injected into the linac and propagated through the system. The configuration permits injection without geometric beam merging as well as decelerated beam extraction without the use of typical beamline elements.

Douglas, David R. (York County, VA)

2012-01-10T23:59:59.000Z

151

HIGH CURRENT ENERGY RECOVERY LINAC AT BNL.  

SciTech Connect

We present the design and parameters of an energy recovery linac (ERL) facility, which is under construction in the Collider-Accelerator Department at BNL. This R&D facility has the goal of demonstrating CW operation of an ERL with an average beam current in the range of 0.1-1 ampere and with very high efficiency of energy recovery. The possibility of a future upgrade to a two-pass ERL is also being considered. The heart of the facility is a 5-cell 703.75 MHz super-conducting RF linac with strong Higher Order Mode (HOM) damping. The flexible lattice of the ERL provides a test-bed for exploring issues of transverse and longitudinal instabilities and diagnostics of intense CW electron beams. This ERL is also perfectly suited for a far-IR FEL. We present the status and plans for construction and commissioning of this facility.

LITVINENKO,V.N.; BEN-ZVI,I.; BARTON,D.S.; ET AL.

2005-05-16T23:59:59.000Z

152

Main Linac Single Bunch Emittance Preservation  

NLE Websites -- All DOE Office Websites (Extended Search)

linear accelerator design which was considered in this study was an adaptation of the TESLA TDR design 1 to the requirements of the parameters document of the US Linear...

153

Suppressing Thermal Energy Drift In The LLNL Flash X-Ray Accelerator Using Linear Disk Resistor Stacks  

SciTech Connect

This paper addresses thermal drift in sodium thiosulfate liquid resistors and their replacement with linear disk resistors from HVR Advanced Power Components. Sodium thiosulfate resistors in the FXR induction linear accelerator application have a temperature coefficient of {approx}1.8%/C. The FXR Marx banks send an 8kJ pulse through eight 524 cm{sup 3} liquid resistors at a repetition rate of up to 1 every 45 seconds. Every pulse increases the temperature of the solution by {approx}0.4 C which produces a 0.7% change in resistance. The typical cooling rate is {approx}0.4 C per minute which results in {approx}0.1% energy drop per pulse during continuous pulsed operations. A radiographic accelerator is extraordinarily sensitive to energy variations. Changes in beam energy produce movement in beam transport, changes in spot size, and large dose variations. If self-heating were the only problem, we could predict the increase in input voltage required to compensate for the energy loss. However, there are other variables that influence the temperature of the resistors such as focus magnet heating, changes in room temperature, changes in cooling water, where the cell is located, etc. Additionally not all of the resistors have equivalent cooling rates and as many as 32 resistors are driven from a single power source. The FXR accelerator group elected to replace the sodium thiosulfate resistors with HVR Linear Disk Resistors in a stack type configuration. With data limited for these resistors when used in oil and at low resistance values, a full characterization needed to be performed. High currents (up to 15kA), high voltages (up to 400kV), and Fast Rise times (<10ns) made a resistor choice difficult. Other solid resistors have been tried and had problems at the connection points and with the fact that the resistivity changed as they absorbed oil. The selected HVR resistors have the advantage of being manufactured with the oil impregnated in to them so this characteristic is minimized while still offering the desired low temperature coefficient of resistance compared to sodium thiosulfate. The characterization experiments and comparison with the sodium thiosulfate liquid resistors will be fully discussed and the final design described.

Kreitzer, B R; Houck, T L; Luchterhand, O C

2011-07-19T23:59:59.000Z

154

A Compact X-Band Linac for an X-Ray FEL  

SciTech Connect

With the growing demand for FEL light sources, cost issues are being reevaluated. To make the machines more compact, higher frequency room temperature linacs are being considered, specifically ones using C-band (5.7 GHz) rf technology, for which 40 MV/m gradients are achievable. In this paper, we show that an X-band (11.4 GHz) linac using the technology developed for NLC/GLC can provide an even lower cost solution. In particular, stable operation is possible at gradients of 100 MV/m for single bunch operation and 70 MV/m for multibunch operation. The concern, of course, is whether the stronger wakefields will lead to unacceptable emittance dilution. However, we show that the small emittances produced in a 250 MeV, low bunch charge, LCLS-like S-band injector and bunch compressor can be preserved in a multi-GeV X-band linac with reasonable alignment tolerances. The successful lasing and operation of the LCLS [1] has generated world-wide interest in X-ray FELs. The demand for access to such a light source by researchers eager to harness the capabilities of this new tool far exceeds the numbers that can be accommodated, spurring plans for additional facilities. Along with cost, spatial considerations become increasingly important for a hard X-ray machine driven by a multi-GeV linac. The consequent need for high acceleration gradient focuses attention on higher frequency normal conducting accelerator technology, rather than the superconducting technology of a soft X-ray facility like FLASH. C-band technology, such as used by Spring-8, is a popular option, capable of providing 40 MV/m. However, more than a decade of R&D toward an X-band linear collider, centered at SLAC and KEK, has demonstrated that this frequency option can extend the gradient reach to the 70-100 MV/m range. The following design and beam dynamics calculations show an X-band linac to be an attractive choice on which to base an X-ray FEL.

Adolphsen, Chris; Huang, Zhirong; Bane, Karl L.F.; Li, Zenghai; Zhou, Feng; Wang, Faya; Nantista, Christopher D.; /SLAC

2011-09-12T23:59:59.000Z

155

Survey of Advanced Dielectric Wakefield Accelerators  

NLE Websites -- All DOE Office Websites (Extended Search)

out wakefield accelerator research. Wakefield Acceleration at AATF The AATF had an electron beam produced by an L- band thermionic RF gun followed by two traveling-wave linac...

156

IMPACT simulation and the SNS linac beam  

E-Print Network (OSTI)

dynamics studies of the SNS linac systems were performedIMPACT SIMULATION AND THE SNS LINAC BEAM * Y. Zhang 1 , J.tracking simulations for the SNS linac beam dynamics studies

Zhang, Y.

2009-01-01T23:59:59.000Z

157

Conceptual Design for Replacement of the DTL and CCL with Superconducting RF Cavities in the Spallation Neutron Source Linac  

Science Conference Proceedings (OSTI)

The Spallation Neutron Source Linac utilizes normal conducting RF cavities in the low energy section from 2.5 MeV to 186 MeV. Six Drift Tube Linac (DTL) structures accelerate the beam to 87 MeV, and four Coupled Cavity Linac (CCL) structures provide further acceleration to 186 MeV. The remainder of the Linac is comprised of 81 superconducting cavities packaged in 23 cryomodules to provide final beam energy of approximately 1 GeV. The superconducting Linac has proven to be substantially more reliable than the normal conducting Linac despite the greater number of stations and the complexity associated with the cryogenic plant and distribution. A conceptual design has been initiated on a replacement of the DTL and CCL with superconducting RF cavities. The motivation, constraints, and conceptual design are presented.

Champion, Mark S [ORNL; Doleans, Marc [ORNL; Kim, Sang-Ho [ORNL

2013-01-01T23:59:59.000Z

158

ANNUAL REPORT, ACCELERATOR and FUSION RESEARCH DIVISION. FISCAL YEAR 1978  

E-Print Network (OSTI)

Accelerator Conceptual Design, HI-FAN-58, 9/6/78. L.J.and Example Design of 1 MJ RF Linac System, HI-FAN-45, (LBL-

Lofgren, E.J.

2010-01-01T23:59:59.000Z

159

An overview of LINAC ion sources  

SciTech Connect

This paper discusses ion sources used in high-duty-factor proton and H{sup -} Linacs as well as in accelerators utilizing multi-charged heavy ions, mostly for nuclear physics applications. The included types are Electron Cyclotron Resonance (ECR) sources as well as filament and rf driven multicusp sources. The paper does not strive to attain encyclopedic character but rather to highlight major lines of development, peak performance parameters and type-specific limitations and problems of these sources. The main technical aspects being discussed are particle feed, plasma generation and ion production by discharges, and plasma confinement.

Keller, Roderich [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

160

Photo of the Week: Lego Rendition of SLAC National Laboratory's Linear  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Lego Rendition of SLAC National Laboratory's Lego Rendition of SLAC National Laboratory's Linear Particle Accelerator Photo of the Week: Lego Rendition of SLAC National Laboratory's Linear Particle Accelerator February 4, 2013 - 10:26am Addthis At two miles long, SLAC's linear particle accelerator is a monster of a machine. But now, thanks to an old collection of Legos and some creative work by SLAC graphic designer Greg Stewart, the two-mile accelerator has been drastically reduced in size. After happening upon his Legos at home one night, Stewart decided to spend his evening designing, building and photographing this Lego diorama homage to the inside of the SLAC linac, a place that's 20 feet underground and not often seen by anyone besides the accelerator engineers who work there. SLAC's safety officers will even be pleased to see the Lego workers wearing their "PPE" (personal protective equipment, in this case helmets). See an actual photo of the SLAC linac. | Photo courtesy of Greg Stewart, SLAC National Accelerator Laboratory.

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

RESEARCH AND DEVELOPMENT FOR AN X-BAND LINEAR COLLIDER* C. Adolphsen  

NLE Websites -- All DOE Office Websites (Extended Search)

AND DEVELOPMENT FOR AN AND DEVELOPMENT FOR AN X-BAND LINEAR COLLIDER* C. Adolphsen Stanford Linear Accelerator Center, Stanford University, Stanford CA 94309 USA Abstract At SLAC and KEK research is advancing toward a design for an electron-positron linear collider based on X-Band (11.4 GHz) rf accelerator technology. The nominal acceleration gradient in its main linacs will be about four times that in the Stanford Linear Collider (SLC). The design targets a 1.0 TeV center-of-mass energy but envisions initial operation at 0.5 TeV and allows for expansion to 1.5 TeV. A 10 34 cm -2 s -1 luminosity level will be achieved by colliding multiple bunches per pulse with bunch emittances about two orders of magnitude smaller than those in the SLC. The key components needed to realize such a collider are

162

Accelerator Update | Archive | 2012  

NLE Websites -- All DOE Office Websites (Extended Search)

2 Accelerator Update Archive 2 Accelerator Update Archive April 27, 2012 - April 30, 2012 NuMI reported receiving 7.67E18 protons on target for the period from 4/23/12 to 4/30/12. The Booster developed an aperture restriction that required lower beam intensity Main Injector personnel completed their last study The shutdown begins Linac, MTA, and Booster will continue using beam for one or two more weeks Linac will supply the Neutron Therapy Facility beam for most of the shutdown April 25, 2012 - April 27, 2012 Booster beam stop problem repaired Beam to all experiments will shut off at midnight on Monday morning, 4/30/12. Main Injector will continue to take beam until 6 AM on Monday morning. Linac, the Neutron Therapy Facility, MTA, and Booster will continue using beam for one or two more weeks. The Fermi Accelerator Complex will be in shutdown for approximately one year

163

Frequency scaling of linear super-colliders  

SciTech Connect

The development of electron-positron linear colliders in the TeV energy range will be facilitated by the development of high-power rf sources at frequencies above 2856 MHz. Present S-band technology, represented by the SLC, would require a length in excess of 50 km per linac to accelerate particles to energies above 1 TeV. By raising the rf driving frequency, the rf breakdown limit is increased, thereby allowing the length of the accelerators to be reduced. Currently available rf power sources set the realizable gradient limit in an rf linac at frequencies above S-band. This paper presents a model for the frequency scaling of linear colliders, with luminosity scaled in proportion to the square of the center-of-mass energy. Since wakefield effects are the dominant deleterious effect, a separate single-bunch simulation model is described which calculates the evolution of the beam bunch with specified wakefields, including the effects of using programmed phase positioning and Landau damping. The results presented here have been obtained for a SLAC structure, scaled in proportion to wavelength.

Mondelli, A.; Chernin, D.; Drobot, A.; Reiser, M.; Granatstein, V.

1986-06-01T23:59:59.000Z

164

University, Linear Accelerator  

E-Print Network (OSTI)

proposals for innovative, econanical, low head hydro power plant ides development. For this purpose, low head was defined as 3m or less. Early hydra power projects were small scale and very close to load centers. Inefficient paddlewheels turned shafts in udlls which, through belts, drove mill equipmt. With the advent of electrical wr, hydro power projects could be reasonably rarote from load centers and located at optimm sites of high head and intermediate flew or high flow and intermediate head. The best sites were quickly exploited and secondary sites became uneconanical. Secondary sites or those evenmre rmte fran load centers were then erploitedby public agencies and the ec onanics justified by power generation plus flood control and/or irrigation plus establistrnent of potable water reservoirs, to serve rapidly growing urban centers. Many of the earlier dams no longer were used to generate power as the mill-races vanished. Many nw low head dams were used for flood control and evening flows toward hydro ver ejects, and were not furnished with generators since these sites were even m3re rarPte

F. F. -hall; P. Box

1980-01-01T23:59:59.000Z

165

Superconducting radiofrequency linac development at Fermilab  

SciTech Connect

As the Fermilab Tevatron Collider program draws to a close, a strategy has emerged of an experimental program built around the high intensity frontier. The centerpiece of this program is a superconducting H- linac that will support world leading programs in long baseline neutrino experimentation and the study of rare processes. Based on technology shared with the International Linear Collider, Project X will provide multi-MW beams at 60-120 GeV from the Main Injector, simultaneous with very high intensity beams at lower energies. Project X also supports development of a Muon Collider as a future facility at the energy frontier.

Holmes, Stephen D.; /Fermilab

2009-10-01T23:59:59.000Z

166

BEAM STUDIES AT THE SNS LINAC  

Science Conference Proceedings (OSTI)

The most recent beam dynamics studies at the Spallation Neutron Source (SNS) linac, including major beam loss reduction efforts in the normal conducting linac and in the superconducting linac (SCL), and the simulation and measurement of longitudinal beam halo and longitudinal acceptance at the entrance of the SCL are discussed. Oscillation of the beam centroid around the linac synchronous phase and the phase adiabatic damping curves in the SNS linac are investigated with linac longitudinal models and measured with all the linac beam phase monitors.

Zhang, Yan [ORNL

2009-01-01T23:59:59.000Z

167

Linear Collider Collaboration Tech Notes LCC-0073 SLAC-PUB-9004  

NLE Websites -- All DOE Office Websites (Extended Search)

3 3 SLAC-PUB-9004 September 2001 Microwave Quadrupoles for Beam Break-up Supression In the NLC Main Linac K.L.F. Bane and G. Stupakov Stanford Linear Accelerator Center Stanford, CA Abstract: This is a preliminary study of the effect of using microwave quads (MQs) instead of rf phase shifting to induce BNS damping in the main linac of the NLC collider. We consider MQs running at X-band, and find that the total length of MQs needed for the NLC is 6% of the total length of the accelerating structures. We show through simulations that, by using MQs instead of phase shifting for BNS damping, the quad alignment tolerances can be relaxed but at the expense of shifting the tight tolerances to the MQs; this can be advantageous if the MQs can be better aligned

168

Factors Predictive of Symptomatic Radiation Injury After Linear Accelerator-Based Stereotactic Radiosurgery for Intracerebral Arteriovenous Malformations  

SciTech Connect

Purpose: To investigate predictive factors in the development of symptomatic radiation injury after treatment with linear accelerator-based stereotactic radiosurgery for intracerebral arteriovenous malformations and relate the findings to the conclusions drawn by Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC). Methods and Materials: Archived plans for 73 patients who were treated at the British Columbia Cancer Agency were studied. Actuarial estimates of freedom from radiation injury were calculated using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards models were used for analysis of incidence of radiation injury. Log-rank test was used to search for dosimetric parameters associated with freedom from radiation injury. Results: Symptomatic radiation injury was exhibited by 14 of 73 patients (19.2%). Actuarial rate of symptomatic radiation injury was 23.0% at 4 years. Most patients (78.5%) had mild to moderate deficits according to Common Terminology Criteria for Adverse Events, version 4.0. On univariate analysis, lesion volume and diameter, dose to isocenter, and a V{sub x} for doses {>=}8 Gy showed statistical significance. Only lesion diameter showed statistical significance (p < 0.05) in a multivariate model. According to the log-rank test, AVM volumes >5 cm{sup 3} and diameters >30 mm were significantly associated with the risk of radiation injury (p < 0.01). The V{sub 12} also showed strong association with the incidence of radiation injury. Actuarial incidence of radiation injury was 16.8% if V{sub 12} was <28 cm{sup 3} and 53.2% if >28 cm{sup 3} (log-rank test, p = 0.001). Conclusions: This study confirms that the risk of developing symptomatic radiation injury after radiosurgery is related to lesion diameter and volume and irradiated volume. Results suggest a higher tolerance than proposed by QUANTEC. The widely differing findings reported in the literature, however, raise considerable uncertainties.

Herbert, Christopher, E-mail: cherbert@bccancer.bc.ca [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver, BC (Canada); Moiseenko, Vitali [Department of Medical Physics, British Columbia Cancer Agency, Vancouver, BC (Canada); McKenzie, Michael [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver, BC (Canada); Redekop, Gary [Division of Neurosurgery, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Canada); Hsu, Fred [Department of Radiation Oncology, British Columbia Cancer Agency, Abbotsford, BC (Canada); Gete, Ermias; Gill, Brad; Lee, Richard; Luchka, Kurt [Department of Medical Physics, British Columbia Cancer Agency, Vancouver, BC (Canada); Haw, Charles [Division of Neurosurgery, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Canada); Lee, Andrew [Department of Neurosurgery, Royal Columbian Hospital, New Westminster, BC (Canada); Toyota, Brian [Division of Neurosurgery, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Canada); Martin, Montgomery [Department of Medical Imaging, British Columbia Cancer Agency, Vancouver, BC (Canada)

2012-07-01T23:59:59.000Z

169

Intensity Effects of the FACET Beam in the SLAC Linac  

SciTech Connect

The beam for FACET (Facility for Advanced aCcelerator Experimental Tests) at SLAC requires an energy-time correlation ('chirp') along the linac, so it can be compressed in two chicanes, one at the midpoint in sector 10 and one W-shaped chicane just before the FACET experimental area. The induced correlation has the opposite sign to the typical used for BNS damping, and therefore any orbit variations away from the center kick the tail of the beam more than the head, causing a shear in the beam and emittance growth. Any dispersion created along the linac has similar effects due to the high (>1.2% rms) energy spread necessary for compression. The initial huge emittances could be reduced by a factor of 10, but were still bigger than expected by a factor of 2-3. Normalized emittance of 3 {micro}m-rad in Sector 2 blew up to 150 {micro}m-rad in Sector 11 but could be reduced to about 6-12 {micro}m-rad, for the vertical plane although the results were not very stable. Investigating possible root causes for this, we found locations where up to 10 mm dispersion was created along the linac, which were finally verified with strong steering and up to 7 mm settling of the linac accelerator at these locations.

Decker, F.-J.; Lipkowitz, N.; Sheppard, J.; White, G.R.; Wienands, U.; Woodley, M.; Yocky, G.; /SLAC

2012-07-03T23:59:59.000Z

170

INCREASED UNDERSTANDING OF BEAM LOSSES FROM THE SNS LINAC PROTON EXPERIMENT  

Science Conference Proceedings (OSTI)

Beam loss is a major concern for high power hadron accelerators such as the Spallation Neutron Source (SNS). An unexpected beam loss in the SNS superconducting linac (SCL) was observed during the power ramp up and early operation. Intra-beam-stripping (IBS) loss, in which interactions between H- particles within the accelerated bunch strip the outermost electron, was recently identified as a possible cause of the beam loss. A set of experiments using proton beam acceleration in the SNS linac was conducted, which supports IBS as the primary beam loss mechanism in the SNS SCL.

Aleksandrov, Alexander V [ORNL; Shishlo, Andrei P [ORNL; Plum, Michael A [ORNL; Lebedev, Valerie [FNAL; Laface, Emanuele [ESS; Galambos, John D [ORNL

2013-01-01T23:59:59.000Z

171

Design features of high-intensity medium-energy superconducting heavy-ion Linac.  

DOE Green Energy (OSTI)

The proposed Rare Isotope Accelerator (RIA) requires the construction of a cw 1.4 GV superconducting (SC) linac that is capable of producing 400 kW beams of all ions from protons at 900 MeV to uranium at 400 MeV/u. The design of such a linac was outlined at the previous Linac conference. This linac will accelerate multiple-charge-states (multi-q) of the heaviest ion beams, for which the beam current is limited by ion-source performance. The linac consists of two different types of accelerating and focusing lattice: for uranium below {approx}85 MeV/u the focusing is provided by SC solenoids installed in cryostats with the SC resonators while in the high-beta section the focusing elements are located outside of the cryostats. A detailed design has been developed for the focusing-accelerating lattice of the linac. Beam dynamics studies have been performed with the goal of optimization of the linac structure in order to reduce a possible effective emittance growth of the multi-q uranium beam. A wide tuning range of the accelerating and focusing fields is required for acceleration of the variety of ions with different charge-to-mass ratios to the highest possible energy in single charge state mode. The focusing must be retuned for different ion masses to avoid resonance coupling between the transverse and longitudinal motions. Any visible impact of this coupling on the formation of beam halo must be avoided due to the high beam power.

Ostroumov, P. N.

2002-09-20T23:59:59.000Z

172

Accelerator Update | Archive | 2010  

NLE Websites -- All DOE Office Websites (Extended Search)

10 Accelerator Update Archive 10 Accelerator Update Archive December 20, 2010 - December 22, 2010 - Three stores provided !32 hours of luminosity - Problems with two Linac quadrupole power supplies - Cryo system technicians work on TEV sector D1 wet engine - TEV quench during checkout - JASMIN's run at MTest ends December 17, 2010 - December 20, 2010 The Integrated Luminosity for the period from 12/13/10 to 12/20/10 was 66.31 inverse picobarns. NuMI reported receiving 7.62E18 protons on target during this same period. - Five Stores provided ~62 hours of luminosity - Operations had trouble with a Linac RF station (LRF3) - Operators tuned the Linac backup source (I- Source) December 15, 2010 - December 17, 2010 - Three stores provided ~36.1 hours of luminosity - MI-52 Septa repaired - NuMI recovered its target LCW system

173

Relative Humidity in Limited Streamer Tubes for Stanford Linear Accelerator Center's BaBar Detector  

SciTech Connect

The BABAR Detector at the Stanford Linear Accelerator Center studies the decay of B mesons created in e{sup +}e{sup -} collisions. The outermost layer of the detector, used to detect muons and neutral hadrons created during this process, is being upgraded from Resistive Plate Chambers (RPCs) to Limited Streamer Tubes (LSTs). The standard-size LST tube consists of eight cells, where a silver-plated wire runs down the center of each. A large potential difference is placed between the wires and ground. Gas flows through a series of modules connected with tubing, typically four. LSTs must be carefully tested before installation, as it will be extremely difficult to repair any damage once installed in the detector. In the testing process, the count rate in most modules showed was stable and consistent with cosmic ray rate over an approximately 500 V operating range between 5400 to 5900 V. The count in some modules, however, was shown to unexpectedly spike near the operation point. In general, the modules through which the gas first flows did not show this problem, but those further along the gas chain were much more likely to do so. The suggestion was that this spike was due to higher humidity in the modules furthest from the fresh, dry inflowing gas, and that the water molecules in more humid modules were adversely affecting the modules' performance. This project studied the effect of humidity in the modules, using a small capacitive humidity sensor (Honeywell). The sensor provided a humidity-dependent output voltage, as well as a temperature measurement from a thermistor. A full-size hygrometer (Panametrics) was used for testing and calibrating the Honeywell sensors. First the relative humidity of the air was measured. For the full calibration, a special gas-mixing setup was used, where relative humidity of the LST gas mixture could be varied from almost dry to almost fully saturated. With the sensor calibrated, a set of sensors was used to measure humidity vs. time in the LSTs. The sensors were placed in two sets of LST modules, one gas line flowing through each set. These modules were tested for count rate v. voltage while simultaneously measuring relative humidity in each module. One set produced expected readings, while the other showed the spike in count rate. The relative humidity in the two sets of modules looked very similar, but it rose significantly for modules further along the gas chain.

Lang, M.I.; /MIT; Convery, M.; /SLAC; Menges, W.; /Queen Mary, U. of London

2005-12-15T23:59:59.000Z

174

The CEBAF cryogenic system: Continuous Electron Beam Accelerator Facility  

SciTech Connect

The CEBAF superconducting linear accelerator incorporates cryogenic refrigeration equipment at three locations within the site: the Central Helium Liquefier, located in the center of the accelerator; the experimental end station refrigerator; and the test laboratory refrigerator located in the Cryogenic Test Facility (CTF) adjacent to the test laboratory. The CEBAF cryogenic system will provide 2K refrigeration to the linacs of the accelerator and test laboratory and 4.5K refrigeration for the end station experimental halls. The Central Helium Liquefier and the test laboratory systems will produce 45K supercritical gaseous helium for shield refrigeration. Liquid nitrogen shields will also be incorporated in the test laboratory and end stations. 6 refs., 5 figs.

Chronis, W.C.; Arenius, D.; Kashy, D.; Keesee, M.; Rode, C.H.

1989-01-01T23:59:59.000Z

175

A Program for Optimizing SRF Linac Costs  

Science Conference Proceedings (OSTI)

Every well-designed machine goes through the process of cost optimization several times during its design, production and operation. The initial optimizations are done during the early proposal stage of the project when none of the systems have been engineered. When a superconducting radio frequency (SRF) linac is implemented as part of the design, it is often a difficult decision as to the frequency and gradient that will be used. Frequently, such choices are made based on existing designs, which invariably necessitate moderate to substantial modifications so that they can be used in the new accelerator. Thus the fallacy of using existing designs is that they will frequently provide a higher cost machine or a machine with sub-optimal beam physics parameters. This paper describes preliminary results of a new software tool that allows one to vary parameters and understand the effects on the optimized costs of construction plus 10 year operations of an SRF linac, the associated cryogenic facility, and controls, where operations includes the cost of the electrical utilities but not the labor or other costs. It derives from collaborative work done with staff from Accelerator Science and Technology Centre, Daresbury, UK [1] several years ago while they were in the process of developing a conceptual design for the New Light Source project. The initial goal was to convert a spread sheet format to a graphical interface to allow the ability to sweep different parameter sets. The tools also allow one to compare the cost of the different facets of the machine design and operations so as to better understand the tradeoffs.

Powers, Thomas J. [JLAB

2013-04-01T23:59:59.000Z

176

Beam Loss Studies for Rare Isotope Driver Linacs Final Report  

Science Conference Proceedings (OSTI)

The Fortran 90 RIAPMTQ/IMPACT code package is a pair of linked beam-dynamics simulation codes that have been developed for end-to-end computer simulations of multiple-charge-state heavy-ion linacs for future exotic-beam facilities. These codes have multiple charge-state capability, and include space-charge forces. The simulations can extend from the low-energy beam-transport line after an ECR ion source to the end of the linac. The work has been performed by a collaboration including LANL, LBNL, ANL, and MSU. The code RIAPMTQ simulates the linac front-end beam dynamics including the LEBT, RFQ, and MEBT. The code IMPACT simulates the beam dynamics of the main superconducting linac. The codes have been benchmarked for rms beam properties against previously existing codes at ANL and MSU. The codes allow high-statistics runs on parallel supercomputing platforms, particularly at NERSC at LBNL, for studies of beam losses. The codes also run on desktop PC computers for low-statistics work. The code package is described in more detail in a recent publication [1] in the Proceedings of PAC07 (2007 US Particle Accelerator Conference). In this report we describe the main activities for the FY07 beam-loss studies project using this code package.

Wangler, T P; Kurennoy, S S; Billen, J H; Crandall, K R; Qiang, J; Ryne, R D; Mustapha, B; Ostroumov, P; Zhao, Q; York, and R. C.

2008-03-26T23:59:59.000Z

177

HINS Linac front end focusing system R&D  

SciTech Connect

This report summarizes current status of an R&D program to develop a focusing system for the front end of a superconducting RF linac. Superconducting solenoids will be used as focusing lenses in the low energy accelerating sections of the front end. The development of focusing lenses for the first accelerating section is in the production stage, and lens certification activities are in preparation at FNAL. The report contains information about the focusing lens design and performance, including solenoid, dipole corrector, and power leads, and about cryogenic system design and performance. It also describes the lens magnetic axis position measurement technique and discusses scope of an acceptance/certification process.

Apollinari, G.; Carcagno, R.H.; Dimarco, J.; Huang, Y.; Kashikhin, V.V.; Orris, D.F.; Page, T.M.; Rabehl, R.; Sylvester, C.; Tartaglia, M.A.; Terechkine, I.; /Fermilab /Argonne

2008-08-01T23:59:59.000Z

178

Induction Linac Systems Experiments for heavy ion fusion  

Science Conference Proceedings (OSTI)

The Lawrence Berkeley Laboratory and the Lawrence Livermore National Laboratory propose to build at LBL the Induction Linac Systems Experiments (ILSE), the next logical step toward the eventual goal of a heavy ion induction accelerator powerful enough to implode or drive inertial confinement fusion targets. Though much smaller than a driver, ILSE will be at full driver scale in several important parameters. Nearly all accelerator components and beam manipulations required for a driver will be tested. It is expected that ILSE will be built in stages as funds and technical progress allow. The first stage, called Elise will include all of the electrostatic quadrupole focused parts of ILSE.

Herrmannsfeldt, W.B. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Bangerter, R.O. [Lawrence Berkeley Lab., CA (United States). Accelerator and Fusion Research Div.

1994-06-01T23:59:59.000Z

179

RHIC | Accelerator Complex  

NLE Websites -- All DOE Office Websites (Extended Search)

RHIC Accelerators RHIC Accelerators The Relativistic Heavy Ion Collider complex is actually composed of a long "chain" of particle accelerators Heavy ions begin their travels in the Electron Beam Ion Source accelerator (1). The ions then travel to the small, circular Booster (3) where, with each pass, they are accelerated to higher energy. From the Booster, ions travel to the Alternating Gradient Synchrotron (4), which then injects the beams via a beamline (5) into the two rings of RHIC (6). In RHIC, the beams get a final accelerator "kick up" in energy from radio waves. Once accelerated, the ions can "orbit" inside the rings for hours. RHIC can also conduct colliding-beam experiments with polarized protons. These are first accelerated in the Linac (2), and further in the Booster (3), AGS (4), and

180

Intrabeam stripping in H- Linacs  

Science Conference Proceedings (OSTI)

A beam loss in the superconducting part of the SNS linac has been observed during its commissioning and operation. Although the loss does not prevent the SNS high power operation, it results in an almost uniform irradiation of linac components and increased radiation levels in the tunnel. Multi-particle tracking could neither account for the magnitude of the observed loss nor its dependence on machine parameters. It was recently found that the loss is consistent with the intrabeam particle collisions resulting in stripping of H{sup -} ions. The paper describes experimental observations and corresponding analytical estimates of the intrabeam stripping.

Lebedev, V.; Solyak, N.; Ostigy, J.-F.; /Fermilab; Alexandrov, A.; Shishlo, A.; /Oak Ridge

2010-09-01T23:59:59.000Z

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181

Linac Energy Management for LCLS  

SciTech Connect

Linac Energy Management (LEM) is a control system program that scales magnet field set-point settings following a change in beam energy. LEM is necessary because changes in the number, phase, and amplitude of the active klystrons change the beam's rigidity, and therefore, to maintain constant optics, one has to change focusing gradients and bend fields accordingly. This paper describes the basic process, the control system application programs we developed for LEM, and some of the implementation lessons learned at the Linac Coherent Light Source (LCLS).

Chu, Chungming; /SLAC; Iverson, Richard; /SLAC; Krejcik, Patrick; /SLAC; Rogind, Deborah; /SLAC; White, Greg; /SLAC; Woodley, Mark; /SLAC

2012-07-05T23:59:59.000Z

182

Wakefield and RF Kicks Due to Coupler Asymmetry in TESLA-Type Accelerating Cavities  

SciTech Connect

In a future linear collider, such as the International Linear Collider (ILC), trains of high current, low emittance bunches will be accelerated in a linac before colliding at the interaction point. Asymmetries in the accelerating cavities of the linac will generate fields that will kick the beam transversely and degrade the beam emittance and thus the collider performance. In the main linac of the ILC, which is filled with TESLA-type superconducting cavities, it is the fundamental (FM) and higher mode (HM) couplers that are asymmetric and thus the source of such kicks. The kicks are of two types: one, due to (the asymmetry in) the fundamental RF fields and the other, due to transverse wakefields that are generated by the beam even when it is on axis. In this report we calculate the strength of these kicks and estimate their effect on the ILC beam. The TESLA cavity comprises nine cells, one HM coupler in the upstream end, and one (identical, though rotated) HM coupler and one FM coupler in the downstream end (for their shapes and location see Figs. 1, 2) [1]. The cavity is 1.1 m long, the iris radius 35 mm, and the coupler beam pipe radius 39 mm. Note that the couplers reach closer to the axis than the irises, down to a distance of 30 mm.

Bane, K.L.F.; Adolphsen, C.; Li, Z.; /SLAC; Dohlus, M.; Zagorodnov, I.; /DESY; Gonin, I.; Lunin, A.; Solyak, N.; Yakovlev, V.; /Fermilab; Gjonaj, E.; Weiland, T.; /Darmstadt, Tech. Hochsch.

2008-07-07T23:59:59.000Z

183

Novel linac structures for low-beta ions and for muons  

SciTech Connect

Development of two innovative linacs is discussed. (1) High-efficiency normal-conducting accelerating structures for ions with beam velocities in the range of a few percent of the speed of light. Two existing accelerator technologies - the H-mode resonator cavities and transverse beam focusing by permanent-magnet quadrupoles (PMQ) - are merged to create efficient structures for light-ion beams of considerable currents. The inter-digital H-mode accelerator with PMQ focusing (IH-PMQ) has the shunt impedance 10-20 times higher than the standard drift-tube linac. Results of the combined 3-D modeling for an IH-PMQ accelerator tank - electromagnetic computations, beam-dynamics simulations, and thermal-stress analysis - are presented. H-PMQ structures following a short RFQ accelerator can be used in the front end of ion linacs or in stand-alone applications like a compact mobile deuteron-beam accelerator up to a few MeV. (2) A large-acceptance high-gradient linac for accelerating low-energy muons in a strong solenoidal magnetic field. When a proton beam hits a target, many low-energy pions are produced almost isotropically, in addition to a small number of high-energy pions in the forward direction. We propose to collect and accelerate copious muons created as the low-energy pions decay. The acceleration should bring muons to a kinetic energy of {approx}200 MeV in about 10 m, where both an ionization cooling of the muon beam and its further acceleration in a superconducting linac become feasible. One potential solution is a normal-conducting linac consisting of independently fed O-mode RF cavities with wide apertures closed by thin metal windows or grids. The guiding magnetic field is provided by external superconducting solenoids. The cavity choice, overall linac design considerations, and simulation results of muon acceleration are presented. Potential applications range from basic research to homeland defense to industry and medicine.

Kurennoy, Sergey S [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

184

Community petascale project for accelerator science and simulation: Advancing computational science for future accelerators and accelerator technologies  

E-Print Network (OSTI)

Applications include the LCLS rf gun. Pic3P runs on theApplications include the LCLS rf gun design. The frameworkLinac Coherent Light Source (LCLS) at the Stanford Linear

Spentzouris, Panagiotis

2008-01-01T23:59:59.000Z

185

A CONCEPTUAL 3-GEV LANSCE LINAC UPGRADE FOR ENHANCED PROTON RADIOGRAPHY  

Science Conference Proceedings (OSTI)

A conceptual design of a 3-GeV linac upgrade that would enable enhanced proton radiography at the Los Alamos Neutron Science Center (LANSCE) is presented. The upgrade is based on the use of superconducting accelerating cavities to increase the present LANSCE linac output energy from 800 MeV to 3 GeV. The LANSCE linac currently provides negative hydrogen ion (H{sup -}) and proton (H{sup +}) beams to several user facilities that support Isotope Production, NNSA Stockpile Stewardship, and Basic Energy Science programs. Required changes to the front-end, the accelerating structures, and to the RF systems to meet the new performance goals, and changes to the existing beam switchyard to maintain operations for a robust user program are also described.

Garnett, Robert W [Los Alamos National Laboratory; Rybarcyk, Lawrence J. [Los Alamos National Laboratory; Merrill, Frank E. [Los Alamos National Laboratory; O'Hara, James F. [Los Alamos National Laboratory; Rees, Daniel E. [Los Alamos National Laboratory; Walstrom, Peter L. [Los Alamos National Laboratory

2012-05-14T23:59:59.000Z

186

Accelerator technology program. Progress report, January-June 1981  

Science Conference Proceedings (OSTI)

This report covers the activities of Los Alamos National Laboratory's Accelerator Technology Division during the first 6 months of calendar 1981. We discuss the Division's major projects, which reflect a variety of applications and sponsors. The varied technologies concerned with the Proton Storage ring are concerned with the Proton Storage Ring are continuing and are discussed in detail. For the racetrack microtron (RTM) project, the major effort has been the design and construction of the demonstration RTM. Our development of the radio-frequency quadrupole (RFQ) linear accelerator continues to stimulate interest for many possible applications. Frequent contacts from other laboratories have revealed a wide acceptance of the RFQ principle in solving low-velocity acceleration problems. In recent work on heavy ion fusion we have developed ideas for funneling beams from RFQ linacs; the funneling process is explained. To test as many aspects as possible of a fully integrated low-energy portion of a Pion generator for Medical Irradiation (PIGMI) Accelerator, a prototype accelerator was designed to take advantage of several pieces of existing accelerator hardware. The important principles to be tested in this prototype accelerator are detailed. Our prototype gyrocon has been extensively tested and modified; we discuss results from our investigations. Our work with the Fusion Materials Irradiation Test Facility is reviewed in this report.

Knapp, E.A.; Jameson, R.A. (comps.)

1982-05-01T23:59:59.000Z

187

Reliability and Maintainability Issues for the Next Linear Collider  

Science Conference Proceedings (OSTI)

Large accelerators for high energy physics research traditionally have been designed using informal best design, engineering, and management practices to achieve acceptable levels of operational availability. However, the Next Linear Collider(NLC) project presents a particular challenge for operational availability due to the unprecedented size and complexity of the accelerator systems required to achieve the physics goals of high center-of-mass energy and high luminosity. Formal reliability and maintainability analysis, design, and implementation will be required to achieve acceptable operational availability for the high energy physics research program. This paper introduces some of the basic concepts of reliability analysis and applies them to the 2.6-cm microwave power system of the two 10-km-long, 250-GeV linacs that are currently proposed for the NLC design.

Wilson, Zane J.; Gold, Saul L.; Koontz, Ron F.; Lavine, Ted L.; /SLAC

2011-08-26T23:59:59.000Z

188

BNL | Accelerator Test Facility  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerator Test Facility Accelerator Test Facility Home Core Capabilities Photoinjector S-Band Linac Laser Systems CO2 Laser Nd:Yag Laser Beamlines Beamline Simulation Data Beamline Parameters Beam Diagnostics Detectors Beam Schedule Operations Resources Fact Sheet (.pdf) Image Library Upgrade Proposal (.pdf) Publications ES&H Experiment Start-up ATF Handbook Laser Safety Collider-Accelerator Dept. C-AD ES&H Resources Staff Users' Place Apply for Access ATF photo ATF photo ATF photo ATF photo ATF photo A user facility for advanced accelerator research The Brookhaven Accelerator Test Facility (ATF) is a proposal driven, steering committee reviewed facility that provides users with high-brightness electron- and laser-beams. The ATF pioneered the concept of a user facility for studying complex properties of modern accelerators and

189

ACCELERATOR SAFETY ENVELOPE  

NLE Websites -- All DOE Office Websites (Extended Search)

LCASE-001, Ver. 3 LCASE-001, Ver. 3 Linac Commissioning Accelerator Safety Envelope For the National Synchrotron Light Source II Photon Sciences Directorate Version 3 December 8, 2011 Prepared by Brookhaven National Laboratory P.O. Box 5000 Upton, NY 11973-5000 managed by Brookhaven Science Associates for the U.S. Department of Energy Office of Science Basic Energy Science under contract DE-AC02-98CD10886 Linac Commissioning Accelerator Safety Envelope (LCASE) ii Photon Sciences Directorate ii DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty,

190

Accelerators for Cancer Therapy  

DOE R&D Accomplishments (OSTI)

The vast majority of radiation treatments for cancerous tumors are given using electron linacs that provide both electrons and photons at several energies. Design and construction of these linacs are based on mature technology that is rapidly becoming more and more standardized and sophisticated. The use of hadrons such as neutrons, protons, alphas, or carbon, oxygen and neon ions is relatively new. Accelerators for hadron therapy are far from standardized, but the use of hadron therapy as an alternative to conventional radiation has led to significant improvements and refinements in conventional treatment techniques. This paper presents the rationale for radiation therapy, describes the accelerators used in conventional and hadron therapy, and outlines the issues that must still be resolved in the emerging field of hadron therapy.

Lennox, Arlene J.

2000-05-30T23:59:59.000Z

191

Zeroth-order design report for the next linear collider. Volume 1  

Science Conference Proceedings (OSTI)

This Zeroth Order Design Report (ZDR) for the Next Linear Collider (NLC) has been completed as a feasibility study for a TeV-scale linear collider that incorporates a room-temperature accelerator powered by rf microwaves at 11.424 GHz--similar to that presently used in the SLC, but at four times the rf frequency. The purpose of this study is to examine the complete systems of such a collider, to understand how the parts fit together, and to make certain that every required piece has been included. The design presented here is not fully engineered in any sense, but to be assured that the NLC can be built, attention has been given to a number of critical components and issues that present special challenges. More engineering and development of a number of mechanical and electrical systems remain to be done, but the conclusion of this study is that indeed the NLC is technically feasible and can be expected to reach the performance levels required to perform research at the TeV energy scale. Volume one covers the following: the introduction; electron source; positron source; NLC damping rings; bunch compressors and prelinac; low-frequency linacs and compressors; main linacs; design and dynamics; and RF systems for main linacs.

Raubenheimer, T.O. [ed.

1996-05-01T23:59:59.000Z

192

Conceptual design for a linear-transformer driver (LTD)-based refurbishment and upgrade of the Saturn accelerator pulse-power system.  

Science Conference Proceedings (OSTI)

The purpose of this work was to develop a conceptual design for the Saturn accelerator using the modular Liner-Transformer Driver (LTD) technology to identify risks and to focus development and research for this new technology. We present a reference design for a Saturn class driver based on a number of linear inductive voltage adders connected in parallel. This design is very similar to a design reported five years ago [1]. However, with the design reported here we use 1-MA, 100-kV LTD cavities as building blocks. These cavities have already been built and are currently in operation at the HCEI in Tomsk, Russia [2]. Therefore, this new design integrates already-proven individual components into a full system design.

Mazarakis, Michael Gerrassimos; Struve, Kenneth William

2006-09-01T23:59:59.000Z

193

Construction of. gamma pi. /sup 0/ spectrometer and photon tagging facility at Bates Linear Accelerator. Final report, July 31, 1979-July 31, 1980  

SciTech Connect

The funds provided under Contract No. DE-AC02-79ER10486 were totally expended for hardware and supplies required by two related devices at the Bates Linear Accelerator. These were a photon tagging facility and a ..gamma pi../sup 0/ spectrometer in Beam Line C of the new South Experimental Hall. Construction was begun in November of 1979 and both systems became fully operational in the summer of 1981. Preliminary data was taken in 1980 with a prototype ..gamma pi../sup 0/ spectrometer will be carried out in the fall of 1981 and spring of 1982. The photon tagging system has been used successfully to calibrate the ..gamma pi../sup 0/ spectrometer for the BU - MIT collaboration and to test a lead glass detector system for Brandeis University.

Booth, E.C.

1981-08-01T23:59:59.000Z

194

AMPERE AVERAGE CURRENT PHOTOINJECTOR AND ENERGY RECOVERY LINAC.  

SciTech Connect

High-power Free-Electron Lasers were made possible by advances in superconducting linac operated in an energy-recovery mode. In order to get to much higher power levels, say a fraction of a megawatt average power, many technological barriers are yet to be broken. We describe work on CW, high-current and high-brightness electron beams. This will include a description of a superconducting, laser-photocathode RF gun employing a new secondary-emission multiplying cathode, an accelerator cavity, both capable of producing of the order of one ampere average current and plans for an ERL based on these units.

BEN-ZVI,I.; BURRILL,A.; CALAGA,R.; ET AL.

2004-08-17T23:59:59.000Z

195

INJECTORS H. Hayano and M. Ross, Chairmen Presentations H. Hayano, "Linac Beam Stability"  

NLE Websites -- All DOE Office Websites (Extended Search)

2 2 INJECTORS H. Hayano and M. Ross, Chairmen Presentations H. Hayano, "Linac Beam Stability" S. Takeda, "Injector Linac Performance" S. Kashiwagi, "ECS Performance" K. Kubo, "Lattice Diagnostic (Linear Optics and Beta-Match)" T. Naito, "Performance of SR Monitor" . . . H. Hayano, "Performance of Alignment Method" J. Urakawa, "Summary of Ring Circumference Issue (Including Wiggler Issue)" N. Terunuma, "Summary of Vacuum Chamber Design Including Ring Impedance" T. Okugi, "Performance of Orbit Measurement" J. Urakawa, "Summary of Emittance Tuning" T. Raubenheimer, "Parameters - Combined Session" D. Yeremian, "Bunching Stability" J. Turner, "Injector Linac Performance"

196

BNL | Accelerators for Applied Research  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerators for Applied Research Accelerators for Applied Research Brookhaven National Lab operates several accelerator facilities dedicated to applied research. These facilities directly address questions and concerns on a tremendous range of fields, including medical imaging, cancer therapy, computation, and space exploration. Leading scientists lend their expertise to these accelerators and offer crucial assistant to collaborating researchers, pushing the limits of science and technology. Interested in gaining access to these facilities for research? See the contact number listed for each facility. RHIC tunnel Brookhaven Linac Isotope Producer The Brookhaven Linac Isoptope Producer (BLIP)-positioned at the forefront of research into radioisotopes used in cancer treatment and diagnosis-produces commercially unavailable radioisotopes for use by the

197

Collider-Accelerator Department  

NLE Websites -- All DOE Office Websites (Extended Search)

RHIC Tunnel and Magnets RHIC Tunnel and Magnets RHIC Tunnel and Magnets AGS Tunnel and Magnets NSRL Beamline RF Kicker Snake 200-MeV LINAC AGS Cold Snake Magnet About the Collider-Accelerator Department The mission of the Collider-Accelerator Department is to develop, improve and operate the suite of particle / heavy ion accelerators used to carry out the program of accelerator-based experiments at BNL; to support the experimental program including design, construction and operation of the beam transports to the experiments plus support of detector and research needs of the experiments; to design and construct new accelerator facilities in support of the BNL and national missions. The C-A Department supports an international user community of over 1500 scientists. The department performs all these functions in an environmentally responsible and safe manner under a rigorous conduct of operations approach.

198

Electromagnetic Design of RF Cavities for Accelerating Low-Energy Muons  

Science Conference Proceedings (OSTI)

A high-gradient linear accelerator for accelerating low-energy muons and pions in a strong solenoidal magnetic field has been proposed for homeland defense and industrial applications. The acceleration starts immediately after collection of pions from a target in a solenoidal magnetic field and brings decay muons, which initially have kinetic energies mostly around 15-20 MeV, to 200 MeV over a distance of {approx}10 m. At this energy, both ionization cooling and further, more conventional acceleration of the muon beam become feasible. A normal-conducting linac with external-solenoid focusing can provide the required large beam acceptances. The linac consists of independently fed zero-mode (TM{sub 010}) RF cavities with wide beam apertures closed by thin conducting edge-cooled windows. Electromagnetic design of the cavity, including its RF coupler, tuning and vacuum elements, and field probes, has been developed with the CST MicroWave Studio, and is presented.

Kurennoy, Sergey S. [Los Alamos National Laboratory

2012-05-14T23:59:59.000Z

199

Resonance Excitation of Longitudinal High Order Modes in Project X Linac  

SciTech Connect

Results of simulation of power loss due to excitation of longitudinal high order modes (HOMs) in the accelerating superconducting RF system of CW linac of Project X are presented. Beam structures corresponding to the various modes of Project X operation are considered: CW regime for 3 GeV physics program; pulsed mode for neutrino experiments; and pulsed regime, when Project X linac operates as a driver for Neutrino Factory/Muon Collider. Power loss and associated heat load due to resonance excitation of longitudinal HOMs are shown to be small in all modes of operation. Conclusion is made that HOM couplers can be removed from the design of superconducting RF cavities of Project X linac.

Khabiboulline, T.N.; Sukhanov, A.AUTHOR = Awida, M.; Gonin, I.; Lunin, A.AUTHOR = Solyak, N.; Yakovlev, V.; /Fermilab

2012-05-01T23:59:59.000Z

200

Beam dynamics studies in the driver LINAC pre-Stripper section of the RIA facility.  

SciTech Connect

The RIA facility driver linac consists of about 400 superconducting (SC) independently phased rf cavities. The linac is designed to accelerate simultaneously several-charge-state beams to generate as much as 400 kW of uranium beam power. The linac beam dynamics is most sensitive to the focusing and accelerating-structure parameters of the prestripper section, where the uranium beam is accelerated from 0.17 keV/u to 9.4 MeV/u. This section is designed to accept and accelerate 2 charge states (28 and 29) of uranium beam from an ECR ion source. The prestripper section must be designed to minimize the beam emittance distortion of this two-charge-state beam. In particular, the inter-cryostat spaces must be minimized and beam parameters near transitions of the accelerating and focusing lattices must be matched carefully. Several sources of possible effective emittance growth are considered in the design of the prestripper section and a tolerance budget is established. Numerical beam dynamics studies include realistic electric and magnetic 3-dimensional field distributions in the SC rf cavities and SC solenoids. Error effects in the longitudinal beam parameters are studied.

Lessner, E. S.; Ostroumov, P. N.

2003-07-10T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Linear Correlation Between Patient Survival and Decreased Percentage of Tumor [{sup 18}F]Fluorodeoxyglucose Uptake for Late-Course Accelerated Hyperfractionated Radiotherapy for Esophageal Cancer  

SciTech Connect

Purpose: The aims of this trial were to study whether a decreased percentage of tumor fluorodeoxyglucose (FDG) uptake (%DeltaSUVmax) correlated with overall survival and local control times for patients with esophageal cancer and which patients would benefit from a late-course accelerated hyperfractionated (LCHF) radiation scheme. Methods and Materials: A total of 50 eligible patients with squamous esophageal cancer received positron-emission tomography examinations three times and were treated with the LCHF radiation scheme, with a dose of 68.4 Gy/41 fractions in 6.5 weeks. A %DeltaSUVmax value was calculated, and patients were stratified as highly radiosensitive (HR), moderately radiosensitive (MR), and low radiosensitivity (LR) according to %DeltaSUVmax values in the conventional fraction (CF) scheme. Then, a linear correlation was calculated between patients' survival time and %DeltaSUVmax. Local control and overall survival rates were compared after stratification. Results: In the MR subgroup, there was no linear correlation between %DeltaSUVmax and the CF and LCHF schemes (correlation coefficient, R < 0.4; p > 0.05). In the other subgroups (HR and LR), %DeltaSUVmax values between the CF and LCHF schemes were correlated. Also, in the HR and LR subgroups, %DeltaSUVmax after radiation correlated with overall survival or local control rates (correlation coefficient, R >0.5, and p < 0.05). Three-year local control rates in the HR, MR, and LR subgroups were 100%, 81.5%, and 0%, respectively (p < 0.001). Also, 3-year overall survival rates were 92.4%, 58.8%, and 0% for HR, MR, and LR subgroups, respectively (p < 0.001). Conclusions: Postradiation %DeltaSUVmax was positively correlated with survival time for patients' with esophageal cancer. Patients who benefited from LCHF schedules were those with a decrease of 30% to 60% in tumor FDG uptake after the completion of CF radiation.

Ma Jinbo; Song Yipeng [Department of Oncology, Shandong University School of Medicine, Shandong Province (China); Department of Radiation Oncology, Yantai Yuhuangding Hospital, School of Medicine, Qingdao University, Yantai (China); Yu Jinming, E-mail: yujmwin@yahoo.cn [Department of Oncology, Shandong University School of Medicine, Shandong Province (China); Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong Province (China); Zhou Wei [Department of Oncology, Shandong University School of Medicine, Shandong Province (China); Cheng Ercheng [Department of Radiation Oncology, Yantai Yuhuangding Hospital, School of Medicine, Qingdao University, Yantai (China); Zhang Xiqin [Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong Province (China)

2012-03-15T23:59:59.000Z

202

Multipass Beam Breakup Study at Jefferson Lab for the 12 GeV CEBAF Upgrade.  

E-Print Network (OSTI)

?? Recirculating linear accelerators (linacs) provide a compact and efficient way of accelerating particle beams to medium and high energies by reusing the same linac… (more)

SHIN, ILKYOUNG

2013-01-01T23:59:59.000Z

203

and Technical Terms AGC Annual Guideline Concentrations  

E-Print Network (OSTI)

Annual Monitoring Report LED Light Emitting Diode LIE Long Island Expressway LINAC Linear Accelerator MCL

204

RHIC Superconducting Accelerator and Electron Cooling Group  

NLE Websites -- All DOE Office Websites (Extended Search)

Organization Chart (PDF) Organization Chart (PDF) Accelerator R&D Division eRHIC R&D Energy Recovery Linac Photocathode R&D Superconducting RF Electron Cooling LARP Center for Accelerator Science and Education C-AD Accelerator R&D Division Superconducting RF Group Group Headed By: Sergey Belomestnykh This web site presents information on the Superconducting Accelerator and RHIC Electron Cooling Group, which is in the Accelerator R&D Division of the Collider-Accelerator Department of Brookhaven National Laboratory. Work is supported mainly by the Division of Nuclear Physics of the US Department of Energy. Upcoming Events: TBD Most recent events: 56 MHz 2nd External Review, March 8-9, 2011 External Review of the Energy Recovery Linac, February 17-18, 2010. Report of the Review Committee

205

Human Accelerator - Teacher Overview  

NLE Websites -- All DOE Office Websites (Extended Search)

electrons. The cavities are arranged in two long, straight sections called Linear Accelerators. In this activity, students pass tennis balls down a line like Jefferson Lab's...

206

Accelerator Technology Division progress report, FY 1993  

Science Conference Proceedings (OSTI)

This report discusses the following topics: A Next-Generation Spallation-Neutron Source; Accelerator Performance Demonstration Facility; APEX Free-Electron Laser Project; The Ground Test Accelerator (GTA) Program; Intense Neutron Source for Materials Testing; Linac Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Radio-Frequency Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operation.

Schriber, S.O.; Hardekopf, R.A.; Heighway, E.A.

1993-12-31T23:59:59.000Z

207

A post accelerator for the U.S. rare isotope accelerator facility.  

SciTech Connect

The proposed Rare Isotope Accelerator (RIA) Facility includes a post-accelerator for rare isotopes (RIB linac) which must produce high-quality beams of radioactive ions over the full mass range, including uranium, at energies above the coulomb barrier, and have high transmission and efficiency. The latter requires the RIB linac to accept at injection ions in the 1+ charge state. A concept for such a post accelerator suitable for ions up to mass 132 has been previously described [1]. This paper presents a modified concept which extends the mass range to uranium. A high resolution separator for purifying beams at the isobaric level precedes the RIB linac. The mass filtering process will provide high purity beams while preserving transmission. For most cases a resolution of about m/{Delta}m=20,000 is adequate at mass A=100 to obtain a separation between isobars of mass excess difference of 5 MeV. The design for a device capable of purifying beams at the isobaric level included calculations up to 5th order. The RIB linac will utilize existing superconducting heavy-ion linac technology for all but a small portion of the accelerator system. The exceptional piece, a very-low-charge-state injector, section needed for just the first few MV of the RIB accelerator, consists of a pre-buncher followed by several sections of cw, normally-conducting RFQ. Two stages of charge stripping are provided: helium gas stripping at energies of a few keV/u, and additional foil stripping at {approx}680 keV/u for the heavier ions. In extending the mass range to uranium, however, for best efficiency the helium gas stripping must be performed at different energies for different mass ions. We present numerical simulations of the beam dynamics of a design for the complete RIB linac which provides for several stripping options and uses cost-effective solenoid focusing elements in the drift-tube linac.

Ostroumov, P. N.; Kelly, M. P.; Kolomiets, A. A.; Nolen, J. A.; Portillo, M.; Shepard, K. W.; Vinogradov, N. E.

2002-06-11T23:59:59.000Z

208

ION ACCELERATOR  

DOE Patents (OSTI)

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 drift tube is splii longitudinally into quadrants supported along the axis of the accelerator by webs from a yoke, the quadrants. webs, and yoke being of magnetic material. A magnetic focusing action is produced by energizing a winding on each web to set up a magnetic field between adjacent quadrants. In the other embodiment the quadrants are electrically insulated from each other and have opposite polarity voltages on adjacent quadrants to provide an electric focusing fleld for the particles, with the quadrants spaced sufficienily close enough to shield the particles within the tube from the accelerating electric field.

Bell, J.S.

1959-09-15T23:59:59.000Z

209

The SNS front-end, an injector for a high-power hydrogen-ion accelerator  

DOE Green Energy (OSTI)

The Spallation Neutron Source (SNS) will be an accelerator-based facility in Oak Ridge, TN, delivering pulsed neutron beams to experimenters. Negative hydrogen ion-beams are generated and pre-accelerated in a 2.5-MeV linac injector, or front end (FE), accelerated to 1 GeV energy by a linear accelerator system, converted into protons and accumulated in a ring accelerator, and then directed towards a mercury target to generate the neutrons. The proton beam arrives at the target in bursts of less than 1 {micro}s duration and with more than 1 MW average power. The front end has been built and commissioned by LBNL in Berkeley; shipment to ORNL is essentially complete. This paper provides an overview of FE major design features and experimental results obtained during the commissioning process. The SNS-FE can be viewed as a prototype of a high-current, high duty-factor injector for other accelerator projects or, without the elaborate MEBT, as an independent 2.5-MeV accelerator for various applications.

Keller, R.

2002-02-01T23:59:59.000Z

210

FINDING OF NO SIGNIFICANT IMPACT FOR LINAC COHERENT LIGHT SOURCE-Il  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

FINDING FINDING OF NO SIGNIFICANT IMPACT FOR LINAC COHERENT LIGHT SOURCE-Il PROJECT SLAC NATIONAL ACCELERATOR LABORATORY AGENCY: U. S. Department of Energy (DOE) ACTION: Finding of No Significant Impact (FONSI) SUMMARY: The U. S. Department of Energy (DOE) has completed an Environmental Assessment (DOE/EA-1904) on a project to expand the existing Linac Coherent Light Source (LCLS) facility at the SLAC National Accelerator Laboratory (SLAC). One of SLAC's major scientific facilities is the LCLS, the world's first hard X-ray free electron laser. The LCLS X-ray laser beams enable the simultaneous investigation of a material's electronic and structural properties on the size (sub-nanometer) and time (femto-second) scales that determine their function. Research programs at SLAC include materials science, catalytic sciences, structural molecular biology, and molecular environmental

211

Prospects for high power Linac Coherent Light Source (LCLS) development in the 1000{angstrom} {minus} 1{angstrom} wavelength range  

Science Conference Proceedings (OSTI)

Electron bunch requirements for single-pass saturation of a Free-Electron Laser (FEL) operating at full transverse coherence in the Self-Amplified Spontaneous Emission (SASE) mode include: (1) a high peak current, (2) a sufficiently low relative energy spread, and (3) a transverse emittance {var_epsilon}[r-m] satisfying the condition {var_epsilon} {le} {lambda}A/4{pi}, where {lambda}[m] is the output wavelength of the FEL. In the insertion device that induces the coherent amplification, the prepared electron bunch must be kept on a trajectory sufficiently collinear with the amplified photons without significant dilution of its transverse density. In this paper we discuss a Linac Coherent Light Source (LCLS) based on a high energy accelerator such as, e.g., the 3km S-band structure at the Stanford Linear Accelerator Center (SLAC), followed by a long high-precision undulator with superimposed quadrupole (FODO) focusing, to fulfill the given requirements for SASE operation in the 1000{Angstrom}--1{Angstrom} range. The electron source for the linac, an RF gun with a laser-excited photocathode featuring a normalized emittance in the 1--3 mm-mrad range, a longitudinal bunch duration of the order of 3 ps, and approximately 10{sup {minus}9} C/bunch, is a primary determinant of the required low transverse and longitudinal emittances. Acceleration of the injected bunch to energies in the 5--25 GeV range is used to reduce the relative longitudinal energy spread in the bunch, as well as to reduce the transverse emittance to values consistent with the cited wavelength regime. Two longitudinal compression stages are employed to increase the peak bunch current to the 2--5 kA levels required for sufficiently rapid saturation. The output radiation is delivered, via a grazing-incidence mirror bank, to optical instrumentation and a multi-user beam line system. Technological requirements for LCLS operation at 40{Angstrom}, 4.5{Angstrom}, and 1.5{Angstrom} are examined.

Tatchyn, R.; Bane, K.; Boyce, R. [and others

1994-03-01T23:59:59.000Z

212

LASER-PLASMA-ACCELERATOR-BASED GAMMA GAMMA COLLIDERS  

E-Print Network (OSTI)

LASER-PLASMA-ACCELERATOR-BASED ?? COLLIDERS ? C. B.linear col- lider based on laser-plasma-accelerators arediscussed, and a laser-plasma-accelerator-based gamma-

Schroeder, C. B.

2010-01-01T23:59:59.000Z

213

A recirculating linac-based facility for ultrafast X-ray science  

SciTech Connect

We present an updated design for a proposed source of ultra-fast synchrotron radiation pulses based on a recirculating superconducting linac, in particular the incorporation of EUV and soft x-ray production. The project has been named LUX - Linac-based Ultrafast X-ray facility. The source produces intense x-ray pulses with duration of 10-100 fs at a 10 kHz repetition rate, with synchronization of 10 s fs, optimized for the study of ultra-fast dynamics. The photon range covers the EUV to hard x-ray spectrum by use of seeded harmonic generation in undulators, and a specialized technique for ultra-short-pulse photon production in the 1-10 keV range. High-brightness rf photocathodes produce electron bunches which are optimized either for coherent emission in free-electron lasers, or to provide a large x/y emittance ration and small vertical emittance which allows for manipulation to produce short-pulse hard x-rays. An injector linac accelerates the beam to 120 MeV, and is followed by four passes through a 600-720 MeV recirculating linac. We outline the major technical components of the proposed facility.

Corlett, J.N; Barletta, W.A.; DeSantis, S.; Doolittle, L.; Fawley, W.M.; Green, M.A.; Heimann, P.; Leone, S.; Lidia, S.; Li, D.; Ratti, A.; Robinson, K.; Schoenlein, R.; Staples, J.; Wan, W.; Wells, R.; Wolski, A.; Zholents, A.; Placidi, M.; Pirkl, W.; Parmigiani, F.

2003-05-06T23:59:59.000Z

214

Alternate Tunings for the Linac Coherent Light Source Photoinjector  

SciTech Connect

The Linac Coherent Light Source (LCLS) is an x-ray free-electron laser (FEL) project based on the SLAC linac. The LCLS Photoinjector beamline has been designed to deliver 10-ps long electron bunches of 1 nC with a normalized projected transverse emittance smaller than 1.2 mm-mrad at 135 MeV. Tolerances and regulation requirements are tight for this tuning. Half of the total emittance at the end of the injector comes from the ''cathode emittance'' which is 0.7 mm-mrad for our nominal 1nC tuning. As the ''cathode emittance'' scales linearly with laser spot radius, the emittance will be dramatically reduced for smaller radius, but this is only possible at lower charge. In particular, for a 0.2 nC charge, we believe we can achieve an emittance closer to 0.4 mm-mrad. This working point will be easier to tune and the beam quality should be much easier to maintain than for the 1 nC case. In the second half of this paper, we discuss optimum laser pulse shapes. We demonstrate that the benefits of the ellipsoidal shapes seem to be important enough so that serious investigations should be carried out in the production of such pulses.

Limborg-Deprey, C.; Emma, P.; /SLAC

2006-03-17T23:59:59.000Z

215

S-Band Loads for SLAC Linac  

SciTech Connect

The S-Band loads on the current SLAC linac RF system were designed, in some cases, 40+ years ago to terminate 2-3 MW peak power into a thin layer of coated Kanthal material as the high power absorber [1]. The technology of the load design was based on a flame-sprayed Kanthal wire method onto a base material. During SLAC linac upgrades, the 24 MW peak klystrons were replaced by 5045 klystrons with 65+ MW peak output power. Additionally, SLED cavities were introduced and as a result, the peak power in the current RF setup has increased up to 240 MW peak. The problem of reliable RF peak power termination and RF load lifetime required a careful study and adequate solution. Results of our studies and three designs of S-Band RF load for the present SLAC RF linac system is discussed. These designs are based on the use of low conductivity materials.

Krasnykh, A.; Decker, F.-J.; /SLAC; LeClair, R.; /INTA Technologies, Santa Clara

2012-08-28T23:59:59.000Z

216

Compact accelerator  

DOE Patents (OSTI)

A compact linear accelerator having at least one strip-shaped Blumlein module which guides a propagating wavefront between first and second ends and controls the output pulse at the second end. Each Blumlein module has first, second, and third planar conductor strips, with a first dielectric strip between the first and second conductor strips, and a second dielectric strip between the second and third conductor strips. Additionally, the compact linear accelerator includes a high voltage power supply connected to charge the second conductor strip to a high potential, and a switch for switching the high potential in the second conductor strip to at least one of the first and third conductor strips so as to initiate a propagating reverse polarity wavefront(s) in the corresponding dielectric strip(s).

Caporaso, George J. (Livermore, CA); Sampayan, Stephen E. (Manteca, CA); Kirbie, Hugh C. (Los Alamos, NM)

2007-02-06T23:59:59.000Z

217

Validation of a virtual source model for Monte Carlo dose calculations of a flattening filter free linac  

SciTech Connect

Purpose: A linac delivering intensity-modulated radiotherapy (IMRT) can benefit from a flattening filter free (FFF) design which offers higher dose rates and reduced accelerator head scatter than for conventional (flattened) delivery. This reduction in scatter simplifies beam modeling, and combining a Monte Carlo dose engine with a FFF accelerator could potentially increase dose calculation accuracy. The objective of this work was to model a FFF machine using an adapted version of a previously published virtual source model (VSM) for Monte Carlo calculations and to verify its accuracy. Methods: An Elekta Synergy linear accelerator operating at 6 MV has been modified to enable irradiation both with and without the flattening filter (FF). The VSM has been incorporated into a commercially available treatment planning system (Monaco Trade-Mark-Sign v 3.1) as VSM 1.6. Dosimetric data were measured to commission the treatment planning system (TPS) and the VSM adapted to account for the lack of angular differential absorption and general beam hardening. The model was then tested using standard water phantom measurements and also by creating IMRT plans for a range of clinical cases. Results: The results show that the VSM implementation handles the FFF beams very well, with an uncertainty between measurement and calculation of <1% which is comparable to conventional flattened beams. All IMRT beams passed standard quality assurance tests with >95% of all points passing gamma analysis ({gamma} < 1) using a 3%/3 mm tolerance. Conclusions: The virtual source model for flattened beams was successfully adapted to a flattening filter free beam production. Water phantom and patient specific QA measurements show excellent results, and comparisons of IMRT plans generated in conventional and FFF mode are underway to assess dosimetric uncertainties and possible improvements in dose calculation and delivery.

Cashmore, Jason; Golubev, Sergey; Dumont, Jose Luis; Sikora, Marcin; Alber, Markus; Ramtohul, Mark [Hall-Edwards Radiotherapy Research Group, University Hospital Birmingham NHS Foundation Trust, United Kingdom, B15 2TH (United Kingdom); Elekta CMS Software, St. Louis, Missouri 63043 (United States); Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen 5021 (Norway); Section for Biomedical Physics, University Hospital for Radiation Oncology, Hoppe-Seyler-Str 3, 72076, Tuebingen (Germany); Hall-Edwards Radiotherapy Research Group, University Hospital Birmingham NHS Foundation Trust, United Kingdom, B15 2TH (United Kingdom)

2012-06-15T23:59:59.000Z

218

The Advanced Superconducting Test Accelerator (ASTA) at Fermilab: A User-Driven Facility Dedicated to Accelerator Science \\& Technology  

E-Print Network (OSTI)

Fermilab is currently constructing a superconducting electron linac that will eventually serve as the backbone of a user-driven facility for accelerator science. This contribution describes the accelerator and summarizes the enabled research thrusts. A detailed description of the facility can be found at [\\url{http://apc.fnal.gov/programs2/ASTA_TEMP/index.shtml}].

Piot, P; Nagaitsev, S; Church, M; Garbincius, P; Henderson, S; Leibfritz, J

2013-01-01T23:59:59.000Z

219

HILBILAC development for accelerator?driven transmutation  

Science Conference Proceedings (OSTI)

High?Intensity Low?Beta Ion Linac (HILBILAC) is intended for acceleration of ion beams with current of about 1 A and higher. The CW HILBILAC with beam current of 250 mA is under development at MRTI. Concept of parameters choice is presented along with results of beam dynamics and resonator parameters calculations. A pulse prototype HILBILAC?TEST will have to be constructed and tested for the CW accelerator development

Vitaly Pirozhenko; Oleg Plink; HILBILAC Study Team

1995-01-01T23:59:59.000Z

220

Multidimensional study of a 50-MeV, 1500-rad/pulse radiographic linac, using the stagger-tuning concept  

Science Conference Proceedings (OSTI)

Stagger tuning of accelerator cavities, or blocks of cavities, can significantly enhance the achievable charge transfer through an electron linac operating in the stored-energy mode. The output bremsstrahlung flux can be increased over a conventional approach by an order of magnitude without any significant degradation in emittance growth or energy spread. Given a suitable injector, a 1500-rad/pulse, 50-MeV radiographic linac appears to be practical at a 400-MHz operating frequency; a 150-rad/pulse, 50-MeV radiographic linac will operate at 1300 MHz. A multidimensional study was made using the PARMELA code where several parameters, including beam current, synchronous phase angle, and beam radius, were varied while observing the effects on emittance and transmission efficiency.

Owen, R.K.; Fazio, M.V.; Boyd, T.J.

1983-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Environmental Assessment for Linac Coherent Light Source Experimental Facility (12/02)  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Stanford Stanford Linear A ccelerator Center DOE/EA-1426 Environmental Assessment for Linac Coherent Light Source Experimental Facility LCLS December 2002 LCLS Environmental Assessment DOE/EA-1426 December 2002 Page - i - Environmental Assessment for LCLS Experimental Facility Table of Contents Preface ............................................................................................................................................ iii 1.0 Summary ................................................................................................................................... 1 2.0 Purpose and Need for LCLS ..................................................................................................... 6 3.0 Description of Proposed Action and Alternatives

222

A Stability of LCLS Linac Modulators  

SciTech Connect

Information concerning to a stability of LCLS RF linac modulators is allocated in this paper. In general a 'pulse-to-pulse' modulator stability (and RF phase as well) is acceptable for the LCLS commission and FEL programs. Further modulator stability improvements are possible and approaches are discussed based on our experimental results.

Decker, F.-J.; Krasnykh, A.; Morris, B.; Nguyen, M.; /SLAC

2012-06-13T23:59:59.000Z

223

Accelerator technology program. Progress report, July-December 1980  

SciTech Connect

The activities of Los Alamos National Laboratory's Accelerator Technology Division are discussed. This report covers the last six months of calendar 1980 and is organized around the Division's major projects. These projects reflect a wide variety of applications and sponsors. The major technological innovations promoted by the Pion Generator for Medical Irradiation (PIGMI) program have been developed; accelerator technologies relevant to the design of a medically practical PIGMI have been identified. A new group in AT Division deals with microwave and magnet studies; we describe the status of some of their projects. We discuss the prototype gyrocon, which has been completed, and the development of the radio-frequency quadrupole linear accelerator, which continues to stimulate interest for many possible applications. One section of this report briefly describes the results of a design study for an electron beam ion source that is ideally suited as an injector for a heavy ion linac; another section reports on a turbine engine test facility that will expose operating turbine engines to simulated maneuver forces. In other sections we discuss various activities: the Fusion Materials Irradiation Test program, the free-electron laser program, the racetrack microtron project, the Proton Storage ring, and H/sup -/ ion sources and injectors.

Knapp, E.A.; Jameson, R.A. (comp.)

1982-01-01T23:59:59.000Z

224

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

CWDD - Continuous Wave Deuterium Demonstrator CWDD - Continuous Wave Deuterium Demonstrator The Continuous Wave Deuterium Demonstrator (CWDD) accelerator, a cryogenically-cooled (26K) linac, was designed to accelerate 80 mA cw of D to 7.5 MeV. CWDD was being built to demonstrate the lauching of a beam with characteristics suitable for a space-based neutral particle-beam (NPB). A considerable amount of hardware was constructed and installed in the Argonne-based facility, and major performance milestones were achieved before program funding ended in October 1993. References - Document Access Guide Continuous Wave Deuterium Demonstrator Final Design Review, Grumman Space Systems, Grumman-Culham Laboratory, Los Alamos (1989). (Located in the Argonne Research Library) Recommissioning and first operation of the CWDD injector at Argonne

225

A Low-Charge, Hard X-Ray FEL Driven with an X-band Injector and Accelerator  

Science Conference Proceedings (OSTI)

After the successful operation of FLASH (Free-Electron Laser in Hamburg) and LCLS (Linac Coherent Light Source), soft and hard X-ray Free Electron Lasers (FELs) are being built, designed or proposed at many accelerator laboratories. Acceleration employing lower frequency RF cavities, ranging from L-band to C-band, is usually adopted in these designs. In the first stage bunch compression, higher-frequency harmonic RF system is employed to linearize the beam's longitudinal phase space, which is nonlinearly chirped during the lower frequency RF acceleration process. In this paper, a hard X-ray FEL design using an all X-band accelerator at 11.424 GHz (from photo-cathode RF gun to linac end) is presented, without the assistance of any harmonic RF linearization. It achieves LCLS-like performance at low charge using X-band linac drivers, which is more versatile, efficient and compact than ones using S-band or C-band rf technology. It employs initially 42 microns long (RMS), low charge (10 pC) electron bunches from an X-band photoinjector. An overall bunch compression ratio of roughly 100 times is proposed in a two stage bunch compressor system. The start-to-end macro-particle 3-D simulation employing several computer codes is presented in this paper, where space charge, wakefields, incoherent and coherent synchrotron radiation (ISR and CSR) effects are included. Employing an undulator with a short period of 1.5 cm, a Genesis FEL simulation shows successful lasing at a wavelength of 0.15 nm with a pulse length of 2 fs and a power saturation length as short as 20 meters, which is equivalent to LCLS low charge mode. Its overall length of both accelerators and undulators is 180 meters (much shorter than the effective LCLS overall length of 1230 meters, including an accelerator length of 1100 meters and an undulator length of 130 meters), which makes it possible to be built in places where only limited space is available.

Sun, Yipeng; Adolphsen, Chris; Limborg-Deprey, Cecile; Raubenheimer, Tor; Wu, Juhao; /SLAC

2012-02-17T23:59:59.000Z

226

Low-Charge, Hard X-Ray Free Electron Laser Driven with an X-Band Injector and Accelerator  

Science Conference Proceedings (OSTI)

After the successful operation of the Free Electron Laser in Hamburg (FLASH) and the Linac Coherent Light Source (LCLS), soft and hard x-ray free electron lasers (FELs) are being built, designed, or proposed at many accelerator laboratories. Acceleration employing lower frequency rf cavities, ranging from L-band to C-band, is usually adopted in these designs. In the first stage bunch compression, higher-frequency harmonic rf system is employed to linearize the beam's longitudinal phase space, which is nonlinearly chirped during the lower frequency rf acceleration process. In this paper, a hard x-ray FEL design using an all X-band accelerator at 11.424 GHz (from photocathode rf gun to linac end) is presented, without the assistance of any harmonic rf linearization. It achieves LCLS-like performance at low charge using X-band linac drivers, which is more versatile, efficient, and compact than ones using S-band or C-band rf technology. It employs initially 42 microns long (rms), low-charge (10 pC) electron bunches from an X-band photoinjector. An overall bunch compression ratio of roughly 100 times is proposed in a two stage bunch compressor system. The start-to-end macroparticle 3D simulation employing several computer codes is presented in this paper, where space charge, wakefields, and incoherent and coherent synchrotron radiation effects are included. Employing an undulator with a short period of 1.5 cm, a Genesis FEL simulation shows successful lasing at a wavelength of 0.15 nm with a pulse length of 2 fs and a power saturation length as short as 20 meters, which is equivalent to LCLS low-charge mode. Its overall length of both accelerators and undulators is 180 meters (much shorter than the effective LCLS overall length of 1230 meters, including an accelerator length of 1100 meters and an undulator length of 130 meters), which makes it possible to be built in places where only limited space is available.

Sun, Yipeng; Adolphsen, Chris; Limborg-Deprey, Cecile; Raubenheimer, Tor; Wu, Juhao; /SLAC

2012-04-17T23:59:59.000Z

227

Commissioning of the Electron Line of the Linac Coherent Light Source. Dose Rate Measurements and Simulations  

Science Conference Proceedings (OSTI)

The Linac Coherent Light Source at the SLAC National Accelerator Laboratory (operated by Stanford University for the US Department of Energy) is the world's first hard X-ray Free Electron Laser machine. It uses high energy electrons delivered by a linac to create ultrafast and brilliant X-ray pulses that can be used as a 'high-speed' camera to obtain images of atoms and molecules. LCLS is a pioneer machine and, as such, its design has encountered unprecedented challenges, the solutions to which will benefit future facilities of its kind across the globe. This article describes the radiation protection aspects of LCLS electron beamlines. Special emphasis is put on the successful commissioning of the LCLS electron line, where, for all examined loss sources, the measured prompt and residual dose rates are in agreement with or below the values predicted through detailed Monte Carlo simulations, used earlier to design the shielding.

Santana Leitner, M; Bauer, J.M.; Fasso, A.; Liu, J.C.; Mao, X.S.; Prinz, A.; Rokni, H.; /SLAC; Sanami, T.; /SLAC /KEK, Tsukuba; Vollaire, J.; /SLAC

2009-05-20T23:59:59.000Z

228

Bunch Shape Monitor for SSCL linac  

SciTech Connect

The Superconducting Super Collider Laboratory and the Institute for Nuclear Research ore collaboratively developing a Bunch Shape Monitor diagnostics for commission the SSCL linac. The Bunch Shape Monitor is designed to measure the intensity of beam as a function of time over the micro-bunch of the beam. Design resolution for the SSCL monitors is approximately 7 psec. The first monitor will operate at the fundamental frequency of 428 MHz and will be used to measure the output beam of the RFQ Linac. First available results will be presented and compared with predictions. Further development will allow the monitors to fit in a standard SSCL beam box and one will operate at the third harmonic of 428 MHz. Proposals to use the Bunch Shape Monitor to measure the longitudinal phase space distribution of the beam will be discussed.

Hurd, J.W.; Arbique, G.M.; Crist, C.E.; Guy, F.W.; Leifeste, G.T.; Raparia, D.; Saadatmand, K.; Swenson, D.A. [Superconducting Super Collider Lab., Dallas, TX (United States); Esin, S.; Feschenko, A.; Stepanov, A.; Mirzojan, A. [AN SSSR, Moscow (Russian Federation). Inst. Yadernykh Issledovanij

1993-05-01T23:59:59.000Z

229

LLRF System Upgrade for the SLAC Linac  

SciTech Connect

The Linac Coherent Light Source (LCLS) at SLAC is in full user operation and has met the stability goals for stable lasing. The 250pC bunch can be compressed to below 100fS before passing through an undulator. In a new mode of operation a 20pC bunch is compressed to about 10fS. Experimenters are regularly using this shorter X-ray pulse and getting pristine data. The 10fS bunch has timing jitter on the order of 100fS. Physicists are requesting that the RF system achieve better stability to reduce timing jitter. Drifts in the RF system require longitudinal feedbacks to work over large ranges and errors result in reduced performance of the LCLS. A new RF system is being designed to help diagnose and reduce jitter and drift in the SLAC linac.

Hong, Bo; /SLAC; Akre, Ron; /SLAC; Pacak, Vojtech; /SLAC

2012-07-06T23:59:59.000Z

230

CLIC simulations from the start of the linac to the interaction point  

E-Print Network (OSTI)

Simulations for linear colliders are traditionally performed separately for the different sub-systems, like damping ring, bunch compressor, linac, and beam delivery. The beam properties are usually passed from one sub-system to the other via bunch charge, RMS transverse emittances, RMS bunch length, average energy and RMS energy spread. It is implicitly assumed that the detailed 6D correlations in the beam distribution are not relevant for the achievable luminosity. However, it has recently been shown that those correlations can have a strong effect on the beam-beam interaction. We present first results on CLIC simulations that integrate linac, beam delivery, and beam-beam interaction. These integrated simulations also allow a better simulation of time-dependent effects, like ground perturbations and interference between several beam-based feedbacks.

Schulte, Daniel; Blair, G A; D'Amico, T E; Leros, Nicolas; Redaelli, S; Risselada, Thys; Zimmermann, Frank

2002-01-01T23:59:59.000Z

231

Analysis on linac quadrupole misalignment in FACET commissioning 2012  

Science Conference Proceedings (OSTI)

In this note, the analysis on linac quadrupole misalignment is presented for the FACET linac section LI05-09 plus LI11-19. The effectiveness of the beam-based alignment technique is preliminarily confirmed by the measurement. Beam-based alignment technique was adopted at SLAC linac since SLC time. Here the beam-based alignment algorithms are further developed and applied in the FACET commissioning during 2012 run.

Sun, Yipeng; /SLAC

2012-07-05T23:59:59.000Z

232

Measurement and correction of accelerator optics  

SciTech Connect

This report reviews procedures and techniques for measuring, correcting and controlling various optics parameters of an accelerator, including the betatron tune, beta function, betatron coupling, dispersion, chromaticity, momentum compaction factor, and beam orbit. The techniques described are not only indispensable for the basic set-up of an accelerator, but in addition the same methods can be used to study more esoteric questions as, for instance, dynamic aperture limitations or wakefield effects. The different procedures are illustrated by examples from several accelerators, storage rings, as well as linacs and transport lines.

Zimmerman, F.

1998-06-01T23:59:59.000Z

233

Adjustable Permanent Quadrupoles Using Rotating Magnet Material Rods for the Next Linear Collider  

Science Conference Proceedings (OSTI)

The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 132 Tesla, with a maximum gradient of 135 Tesla per meter, an adjustment range of +0-20% and effective lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micrometer during the 20% adjustment. In an effort to reduce estimated costs and increase reliability, several designs using hybrid permanent magnets have been developed. All magnets have iron poles and use either Samarium Cobalt or Neodymium Iron to provide the magnetic fields. Two prototypes use rotating rods containing permanent magnetic material to vary the gradient. Gradient changes of 20% and center shifts of less than 20 microns have been measured. These data are compared to an equivalent electromagnet prototype.

James T Volk et al.

2001-09-24T23:59:59.000Z

234

Measurement of ion beam profiles in a superconducting linac with a laser wire  

Science Conference Proceedings (OSTI)

A laser wire ion beam profile monitor system has been developed at the Spallation Neutron Source accelerator complex. The laser wire system uses a single laser source to measure the horizontal and vertical profiles of a pulsed hydrogen ion (H{sup -}) beam along a 230 m long superconducting linac, which accelerates H{sup -} from 200 MeV to 1 GeV. In this paper, we describe the laser optics requirement for the system, the performance of the profile measurement, and the effects of laser parameters on the measurement reliability. The result provides a practical guideline for the development of a large-scale, operational, laser-based diagnostics in accelerator facilities.

Liu Yun; Long, Cary; Peters, Charles; Aleksandrov, Alexander

2010-12-10T23:59:59.000Z

235

Science and Instrumentation for the Linac Coherent Light Source...  

NLE Websites -- All DOE Office Websites (Extended Search)

Science and Instrumentation for the Linac Coherent Light Source WB00852.GIF (317 bytes) Where: SLAC Panofsky Auditorium When: Friday, October 15, 1999 (1:30 pm) Saturday,...

236

New high power 200 MHz RF system for the LANSCE drift tube linac  

SciTech Connect

The Los Alamos Neutron Science Center (LANSCE) linac provides an 800 MeV direct H{sup +} proton beam, and injects H{sup {minus}} to the upgraded proton storage ring for charge accumulation for the Short Pulse Spallation Source. Accelerating these interlaced beams requires high average power from the 201.25 MHz drift tube linac (DTL) RF system. Three power amplifiers have operated at up to three Megawatts with 12% duty factor. The total number of electron power tubes in the RF amplifiers and their modulators has been reduced from fifty-two to twenty-four. The plant continues to utilize the original design of a tetrode driving a super power triode. Further increases in the linac duty factor are limited, in part, by the maximum dissipation ratings of the triodes. A description of the system modifications proposed to overcome these limitations includes new power amplifiers using low-level RF modulation for tank field control. The first high power Diacrode{reg_sign} is being delivered and a new amplifier cavity is being designed. With only eight power tubes, the new system will deliver both peak power and high duty factor, with lower mains power and cooling requirements. The remaining components needed for the new RF system will be discussed.

Lyles, J.; Friedrichs, C.; Lynch, M.

1998-12-31T23:59:59.000Z

237

X-ray Sources by Energy Recovered Linacs and Their Needed R&D  

Science Conference Proceedings (OSTI)

In this paper we review the current state of research on energy recovered linacs as drivers for future X-ray sources. For many types of user experiments, such sources may have substantial advantages compared to the workhorse sources of the present: high energy storage rings. Energy recovered linacs need to be improved beyond present experience in both energy and average current to support this application. To build an energy recovered linac based X-ray user facility presents many interesting challenges. We present summaries on the Research and Development (R&D) topics needed for full development of such a source, including the discussion at the Future Light Sources Workshop held in Gaithersburg, Maryland on September 15- 17, 2009. A #12;rst iteration of an R&D plan is presented that is founded on the notion of building a set of succeedingly larger test accelerators exploring cathode physics, high average current injector physics, and beam recirculation and beam energy recovery at high average current. Our basic conclusion is that a reviewable design of such a source can be developed after an R&D period of #12;ve to ten years.

Benson, Stephen; Douglas, David; Dowell, David; Hernandez-Garcia, Carlos; Kayran, D; Krafft, Geoffrey; Legg, Robert; Moog, E; Obina, T; Rimmer, Robert

2011-05-01T23:59:59.000Z

238

High brightness electron accelerator  

DOE Patents (OSTI)

A compact high brightness linear accelerator is provided for use, e.g., in a free electron laser. The accelerator has a first plurality of acclerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electrons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electrons as the electrons enter the first cavity.

Sheffield, R.L.; Carlsten, B.E.; Young, L.M.

1992-12-31T23:59:59.000Z

239

A post accelerator for the U.S. rare isotope accelerator facility.  

Science Conference Proceedings (OSTI)

Work supported by the U. S. Department of Energy under contract W-31-109-ENG-38. The proposed Rare Isotope Accelerator (RIA) Facility includes a post-accelerator for rare isotopes (RIB linac) which must produce high-quality beams of radioactive ions over the full mass range, including uranium, at energies above the coulomb barrier, and have high transmission and efficiency. The latter requires the RIB linac to accept at injection ions in the 1+ charge state. A concept for such a post accelerator suitable for ions up to mass 132 has been previously described [1]. This paper presents a modified concept which extends the mass range to uranium. A high resolution separator for purifying beams at the isobaric level precedes the RIB linac. The mass filtering process will provide high purity beams while preserving transmission. For most cases a resolution of about m/{Delta}m=20,000 is adequate at mass A=100 to obtain a separation between isobars of mass excess difference of 5 MeV. The design for a device capable of purifying beams at the isobaric level included calculations up to 5th order. The RIB linac will utilize existing superconducting heavy-ion linac technology for all but a small portion of the accelerator system. The exceptional piece, a very-low-charge-state injector, section needed for just the first few MV of the RIB accelerator, consists of a pre-buncher followed by several sections of cw, normally-conducting RFQ. Two stages of charge stripping are provided: helium gas stripping at energies of a few keV/u, and additional foil stripping at {approx}680 keV/u for the heavier ions. In extending the mass range to uranium, however, for best efficiency the helium gas stripping must be performed at different energies for different mass ions. We present numerical simulations of the beam dynamics of a design for the complete RIB linac which provides for several stripping options and uses cost-effective solenoid focusing elements in the drift-tube linac.

Ostroumov, P. N.; Kelly, M. P.; Kolomiets, A. A.; Nolen, J. A.; Portillo, M.; Shepard, K. W.; Vinogradov, N. E.

2002-06-11T23:59:59.000Z

240

Proton Driver Linac for the Frankfurt Neutron Source  

SciTech Connect

The Frankfurt Neutron Source at the Stern-Gerlach-Zentrum (FRANZ) will deliver high neutron fluxes in the energy range of 1 to 500 keV. The Activation Mode provides a high averaged neutron flux created by a cw proton beam of up to 5 mA, while in the Compressor Mode intense neutron pulses of 1 ns length are formed with a repetition rate of up to 250 kHz. The Compressor Mode is well-suited for energy-dependent neutron capture measurements using the Time-of-Flight method in combination with a 4{pi} BaF{sub 2} detector array. The design of the proton driver linac for both operation modes is presented. This includes the volume type ion source, the ExB chopper located in the low energy section, the RFQ-IH combination for beam acceleration and the bunch compressor. Finally, the neutron production at the lithium-7 target and the resulting energy spectrum is described.

Wiesner, C.; Chau, L. P.; Dinter, H.; Droba, M.; Heilmann, M.; Joshi, N.; Maeder, D.; Metz, A.; Meusel, O.; Noll, D.; Podlech, H.; Ratzinger, U.; Reichau, H.; Schempp, A.; Schmidt, S.; Schweizer, W.; Volk, K.; Wagner, C. [Institut fuer Angewandte Physik, Goethe-Universitaet, Max-von-Laue-Str. 1, 60438 Frankfurt/Main (Germany); Reifarth, R. [Institut fuer Angewandte Physik, Goethe-Universitaet, Max-von-Laue-Str. 1, 60438 Frankfurt/Main (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstr. 1, 64291 Darmstadt (Germany); Mueller, I.

2010-08-04T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

SLAC Linac Coherent Light Source User Site  

NLE Websites -- All DOE Office Websites (Extended Search)

Welcome to the LCLS User Resources Site Welcome to the LCLS User Resources Site User Portal | Agreements | Data Collection & Analysis | Logistics | Policies | Proposals | Safety | Schedules | Shipping The Linac Coherent Light Source (LCLS) encourages scientists from diverse fields to submit proposals for experiments that utilize the LCLS's unique capabilities. Interested scientists are encouraged to learn more about the latest developments by contacting LCLS staff scientists and by reviewing the instrument descriptions. Step-By-Step Instructions to Working at LCLS Review LCLS Policies Review Machine FAQ & Parameters Register and Submit Proposals Confirm User Agreement Reserve Accommodations Complete Safety Training Request Computer Account Establish User Account Ship Samples/Equipment Review Check-in Procedures

242

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Chemistry Division Electron Linac (operation: 1969 - ongoing) This high peak current 22 MeV L-band linac was primarily used to study the time profile of chemical reactions. For...

243

Feasibility studies of an accelerator for the intense pulsed neutron source (IPNS)  

SciTech Connect

A proton linac plus synchrotron system was studied for the proposed Intense Pulsed Neutron Source (IPNS) at Argonne. An Alvarez H$sup -$ linac of 70 MeV and a high intensity fast cycling proton synchrotron to accelerate protons to 800 MeV will be the best choice to give a flux of 10$sup 16$ thermal neutron/sec cm$sup 2$ at the surface of moderator with a spallation neutron target of W or $sup 238$U. (auth)

Khoe, T.K.; Kimura, M.

1974-11-01T23:59:59.000Z

244

Properties of Trapped Electron Bunches in a Plasma Wakefield Accelerator  

Science Conference Proceedings (OSTI)

Plasma-based accelerators use the propagation of a drive bunch through plasma to create large electric fields. Recent plasma wakefield accelerator (PWFA) experiments, carried out at the Stanford Linear Accelerator Center (SLAC), successfully doubled the energy for some of the 42 GeV drive bunch electrons in less than a meter; this feat would have required 3 km in the SLAC linac. This dissertation covers one phenomenon associated with the PWFA, electron trapping. Recently it was shown that PWFAs, operated in the nonlinear bubble regime, can trap electrons that are released by ionization inside the plasma wake and accelerate them to high energies. These trapped electrons occupy and can degrade the accelerating portion of the plasma wake, so it is important to understand their origins and how to remove them. Here, the onset of electron trapping is connected to the drive bunch properties. Additionally, the trapped electron bunches are observed with normalized transverse emittance divided by peak current, {epsilon}{sub N,x}/I{sub t}, below the level of 0.2 {micro}m/kA. A theoretical model of the trapped electron emittance, developed here, indicates that the emittance scales inversely with the square root of the plasma density in the non-linear 'bubble' regime of the PWFA. This model and simulations indicate that the observed values of {epsilon}{sub N,x}/I{sub t} result from multi-GeV trapped electron bunches with emittances of a few {micro}m and multi-kA peak currents. These properties make the trapped electrons a possible particle source for next generation light sources. This dissertation is organized as follows. The first chapter is an overview of the PWFA, which includes a review of the accelerating and focusing fields and a survey of the remaining issues for a plasma-based particle collider. Then, the second chapter examines the physics of electron trapping in the PWFA. The third chapter uses theory and simulations to analyze the properties of the trapped electron bunches. Chapters four and five present the experimental diagnostics and measurements for the trapped electrons. Next, the sixth chapter introduces suggestions for future trapped electron experiments. Then, Chapter seven contains the conclusions. In addition, there is an appendix chapter that covers a topic which is extraneous to electron trapping, but relevant to the PWFA. This chapter explores the feasibility of one idea for the production of a hollow channel plasma, which if produced could solve some of the remaining issues for a plasma-based collider.

Kirby, Neil; /SLAC

2009-10-30T23:59:59.000Z

245

Experiment on a Tunable Dielectric-Loaded Accelerating Structure  

NLE Websites -- All DOE Office Websites (Extended Search)

Proceedings of IPAC'10, Kyoto, Japan THPD068 03 Linear Colliders, Lepton Accelerators and New Acceleration Techniques A14 Advanced Concepts 4437 is connected to the...

246

PARTICLE ACCELERATOR  

DOE Patents (OSTI)

ABS>A combination of two accelerators, a cyclotron and a ring-shaped accelerator which has a portion disposed tangentially to the cyclotron, is described. Means are provided to transfer particles from the cyclotron to the ring accelerator including a magnetic deflector within the cyclotron, a magnetic shield between the ring accelerator and the cyclotron, and a magnetic inflector within the ring accelerator.

Teng, L.C.

1960-01-19T23:59:59.000Z

247

A Quest for Measuring Ion Bunch Longitudinal Profiles with One Picosecond Accuracy in the SNS Linac.  

Science Conference Proceedings (OSTI)

The SNS linac utilizes several accelerating structures operating at different frequencies and with different transverse focusing structures. Low-loss beam transport requires a careful matching at the transition points in both the transverse and longitudinal axes. Longitudinal beam parameters are measured using four Bunch Shape Monitors (used at many ion accelerator facilities, aka Feschenko devices). These devices, as initially delivered to the SNS, provided an estimated accuracy of about 5 picoseconds, which was sufficient for the initial beam commissioning. New challenges of improving beam transport for higher power operation will require measuring bunch profiles with 1-2 picoseconds accuracy. We have successfully implemented a number of improvements to maximize the performance characteristics of the delivered devices. We will discuss the current status of this instrument, its ultimate theoretical limit of accuracy, and how we measure its accuracy and resolution with real beam conditions.

Aleksandrov, Alexander V [ORNL; Dickson, Richard W [ORNL

2012-01-01T23:59:59.000Z

248

PHYSICS RESULTS OF THE NSLS-II LINAC FRONT END TEST STAND  

Science Conference Proceedings (OSTI)

The Linac Front End Test Stand (LFETS) was installed at the Source Development Laboratory (SDL) in the fall of 2011 in order to test the Linac Front End. The goal of these tests was to test the electron source against the specifications of the linac. In this report, we discuss the results of these measurements and the effect on linac performance.

Fliller R. P.; Gao, F.; Yang, X.; Rose, J.; Shaftan, T.; Piel, C

2012-05-20T23:59:59.000Z

249

Short-pulse limits in optical instrumentation design for the SLAC Linac Cohereent Light Source (LCLS)  

E-Print Network (OSTI)

Short-pulse limits in optical instrumentation design for the SLAC Linac Cohereent Light Source (LCLS)

Tatchyn, R

1999-01-01T23:59:59.000Z

250

Can Accelerators Accelerate Learning?  

Science Conference Proceedings (OSTI)

The 'Young Talented' education program developed by the Brazilian State Funding Agency (FAPERJ)[1] makes it possible for high-schools students from public high schools to perform activities in scientific laboratories. In the Atomic and Molecular Physics Laboratory at Federal University of Rio de Janeiro (UFRJ), the students are confronted with modern research tools like the 1.7 MV ion accelerator. Being a user-friendly machine, the accelerator is easily manageable by the students, who can perform simple hands-on activities, stimulating interest in physics, and getting the students close to modern laboratory techniques.

Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S. [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil, Caixa Postal 68528, 21941-972 (Brazil)

2009-03-10T23:59:59.000Z

251

SuperB Progress Report for Accelerator  

Science Conference Proceedings (OSTI)

This report details the progress made in by the SuperB Project in the area of the Collider since the publication of the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008. With this document we propose a new electron positron colliding beam accelerator to be built in Italy to study flavor physics in the B-meson system at an energy of 10 GeV in the center-of-mass. This facility is called a high luminosity B-factory with a project name 'SuperB'. This project builds on a long history of successful e+e- colliders built around the world, as illustrated in Figure 1.1. The key advances in the design of this accelerator come from recent successes at the DAFNE collider at INFN in Frascati, Italy, at PEP-II at SLAC in California, USA, and at KEKB at KEK in Tsukuba Japan, and from new concepts in beam manipulation at the interaction region (IP) called 'crab waist'. This new collider comprises of two colliding beam rings, one at 4.2 GeV and one at 6.7 GeV, a common interaction region, a new injection system at full beam energies, and one of the two beams longitudinally polarized at the IP. Most of the new accelerator techniques needed for this collider have been achieved at other recently completed accelerators including the new PETRA-3 light source at DESY in Hamburg (Germany) and the upgraded DAFNE collider at the INFN laboratory at Frascati (Italy), or during design studies of CLIC or the International Linear Collider (ILC). The project is to be designed and constructed by a worldwide collaboration of accelerator and engineering staff along with ties to industry. To save significant construction costs, many components from the PEP-II collider at SLAC will be recycled and used in this new accelerator. The interaction region will be designed in collaboration with the particle physics detector to guarantee successful mutual use. The accelerator collaboration will consist of several groups at present universities and national laboratories. In Italy these may include INFN Frascati and the University of Pisa, in the United States SLAC, LBNL, BNL and several universities, in France IN2P3, LAPP, and Grenoble, in Russia BINP, in Poland Krakow University, and in the UK the Cockcroft Institute. The construction time for this collider is a total of about four years. The new tunnel can be bored in about a year. The new accelerator components can be built and installed in about 4 years. The shipping of components from PEP-II at SLAC to Italy will take about a year. A new linac and damping ring complex for the injector for the rings can be built in about three years. The commissioning of this new accelerator will take about a year including the new electron and positron sources, new linac, new damping ring, new beam transport lines, two new collider rings and the Interaction Region. The new particle physics detector can be commissioned simultaneously with the accelerator. Once beam collisions start for particle physics, the luminosity will increase with time, likely reaching full design specifications after about two to three years of operation. After construction, the operation of the collider will be the responsibility of the Italian INFN governmental agency. The intent is to run this accelerator about ten months each year with about one month for accelerator turn-on and nine months for colliding beams. The collider will need to operate for about 10 years to provide the required 50 ab{sup -1} requested by the detector collaboration. Both beams as anticipated in this collider will have properties that are excellent for use as sources for synchrotron radiation (SR). The expected photon properties are comparable to those of PETRA-3 or NSLS-II. The beam lines and user facilities needed to carry out this SR program are being investigated.

Biagini, M.E.; Boni, R.; Boscolo, M.; Buonomo, B.; Demma, T.; Drago, A.; Esposito, M.; Guiducci, S.; Mazzitelli, G.; Pellegrino, L.; Preger, M.A.; Raimondi, P.; Ricci, R.; Rotundo, U.; Sanelli, C.; Serio, M.; Stella, A.; Tomassini, S.; Zobov, M.; /Frascati; Bertsche, K.; Brachman, A.; /SLAC /Novosibirsk, IYF /INFN, Pisa /Pisa U. /Orsay, LAL /Annecy, LAPP /LPSC, Grenoble /IRFU, SPP, Saclay /DESY /Cockroft Inst. Accel. Sci. Tech. /U. Liverpool /CERN

2012-02-14T23:59:59.000Z

252

Nonlinear Energy Collimation System for Linear Colliders  

E-Print Network (OSTI)

The post-linac energy collimation system of multi-TeV linear colliders is designed to fulfil an important function of protection of the Beam Delivery System (BDS) against miss-steered beams likely generated by failure modes in the main linac. For the case of the Compact Linear Collider (CLIC), the energy collimators are required to withstand the impact of a full bunch train in case of failure. This is a very challenging task, assuming the nominal CLIC beam parameters at 1.5 TeV beam energy. The increase of the transverse spot size at the collimators using nonlinear magnets is a potential solution to guarantee the survival of the collimators. In this paper we present an alternative nonlinear optics based on a skew sextupole pair for energy collimation. Performance simulation results are also presented.

Resta-Lopez, Javier

2011-01-01T23:59:59.000Z

253

PERFORMANCE OF THE DIAGNOSTICS FOR NSLS-II LINAC COMMISSIONING  

Science Conference Proceedings (OSTI)

The National Synchrotron Light Source II (NSLS-II) is a state of the art 3-GeV third generation light source currently under construction at Brookhaven National Laboratory. The NSLS-II injection system consists of a 200 MeV linac, a 3-GeV booster synchrotron and associated transfer lines. The transfer lines not only provide a means to deliver the beam from one machine to another, they also provide a suite of diagnostics and utilities to measure the properties of the beam to be delivered. In this paper we discuss the suite of diagnostics that will be used to commission the NSLS-II linac and measure the beam properties. The linac to booster transfer line can measure the linac emittance with a three screens measurement or a quadrupole scan. Energy and energy spread are measured in a dispersive section. Total charge and charge uniformity are measured with wall current monitors in the linac and transformers in the transfer line. We show that the performance of the diagnostics in the transfer line will be sufficient to ensure the linac meets its specifications and provides a means of trouble shooting and studying the linac in future operation.

Fliller III, R.; Padrazo, D.; Wang, G.M.; Heese, R.; Hseuh H.-C.; Johanson, M.; Kosciuk, B.N.; Pinayev, I.; Rose, J.; Shaftan, T.; Singh, O.

2011-03-28T23:59:59.000Z

254

Technology development for high power induction accelerators  

SciTech Connect

The marriage of Induction Linac technology with Nonlinear Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 MeV/meter, and with power efficiencies approaching 50%. A 2 MeV, 5 kA electron accelerator has been constructed at the Lawrence Livermore National Laboratory (LLNL) to demonstrate these concepts and to provide a test facility for high brightness sources. The pulse drive for the accelerator is based on state-of-the-art magnetic pulse compressors with very high peak power capability, repetition rates exceeding a kilohertz and excellent reliability.

Birx, D.L.; Reginato, L.L.

1985-06-11T23:59:59.000Z

255

High-Performance Beam Simulator for the LANSCE Linac  

SciTech Connect

A high performance multiparticle tracking simulator is currently under development at Los Alamos. The heart of the simulator is based upon the beam dynamics simulation algorithms of the PARMILA code, but implemented in C++ on Graphics Processing Unit (GPU) hardware using NVIDIA's CUDA platform. Linac operating set points are provided to the simulator via the EPICS control system so that changes of the real time linac parameters are tracked and the simulation results updated automatically. This simulator will provide valuable insight into the beam dynamics along a linac in pseudo real-time, especially where direct measurements of the beam properties do not exist. Details regarding the approach, benefits and performance are presented.

Pang, Xiaoying [Los Alamos National Laboratory; Rybarcyk, Lawrence J. [Los Alamos National Laboratory; Baily, Scott A. [Los Alamos National Laboratory

2012-05-14T23:59:59.000Z

256

TRANSVERSE MATCHING PROGRESS OF THE SNS SUPERCONDUCTING LINAC  

Science Conference Proceedings (OSTI)

Experience using laser-wire beam profile measurement to perform transverse beam matching in the SNS superconducting linac is discussed. As the SNS beam power is ramped up to 1 MW, transverse beam matching becomes a concern to control beam loss and residual activation in the linac. In our experiments, however, beam loss is not very sensitive to the matching condition. In addition, we have encountered difficulties in performing a satisfactory transverse matching with the envelope model currently available in the XAL software framework. Offline data analysis from multi-particle tracking simulation shows that the accuracy of the current online model may not be sufficient for modeling the SC linac.

Zhang, Yan [ORNL; Cousineau, Sarah M [ORNL; Liu, Yun [ORNL

2011-01-01T23:59:59.000Z

257

Linear collider: a preview  

Science Conference Proceedings (OSTI)

Since no linear colliders have been built yet it is difficult to know at what energy the linear cost scaling of linear colliders drops below the quadratic scaling of storage rings. There is, however, no doubt that a linear collider facility for a center of mass energy above say 500 GeV is significantly cheaper than an equivalent storage ring. In order to make the linear collider principle feasible at very high energies a number of problems have to be solved. There are two kinds of problems: one which is related to the feasibility of the principle and the other kind of problems is associated with minimizing the cost of constructing and operating such a facility. This lecture series describes the problems and possible solutions. Since the real test of a principle requires the construction of a prototype I will in the last chapter describe the SLC project at the Stanford Linear Accelerator Center.

Wiedemann, H.

1981-11-01T23:59:59.000Z

258

PARTICLE ACCELERATOR  

DOE Patents (OSTI)

A fixed-field alternating gradient accelerator for simultaneous acceleration of two particle beams in opposite directions is described. (T.R.H.)

Ohkawa, T.

1959-06-01T23:59:59.000Z

259

The Linac Coherent Light Source is  

NLE Websites -- All DOE Office Websites (Extended Search)

Coherent Light Source is Coherent Light Source is a revolution in x-ray science. Just as the invention of x-ray machines a century ago astonishingly revealed the inside of our bodies and began new sciences, the world's first x-ray laser will open up unprecedented opportunities. Pioneering experiments will advance our understand ing of everything from the hidden physics inside planets, to how proteins function as the engines of life, to building nanotechnology devices for the backbone of future industry and technology. The applications are legion: medicine, electronics, biology, solid-state physics, nanotechnology, energy production, industry and fields that do not yet exist. Linac Coherent Light Source New Tools Create New Science The LCLS is dramatically different from any x-ray

260

Research Accelerator Division | Neutron Science | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Kevin Jones The Research Accelerator Division is responsible for operation of the SNS accelerator complex, which consists of a negative hydrogen-ion injector, a 1 GeV linear...

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Research Accelerator Division | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Kevin Jones. The Research Accelerator Division (RAD) is responsible for operation of the SNS accelerator complex, which consists of a negative hydrogen-ion injector, a 1 GeV linear...

262

Subcritical Fission Reactor Based on Linear Collider  

E-Print Network (OSTI)

The beams of Linear Collider after main collision can be utilized to build an accelerator--driven sub--critical reactor.

I. F. Ginzburg

2005-07-29T23:59:59.000Z

263

Energy Spread Compensation for Multi-Bunch Linac Operation Mode  

NLE Websites -- All DOE Office Websites (Extended Search)

ENERGY SPREAD COMPENSATION FOR MULTI-BUNCH LINAC OPERATION MODE D. Mihalcea, Northern Illinois University, DeKalb, IL 60115, USA W. Gai, J. G. Power, ANL, Argonne, IL 60439, USA...

264

Compensation of Beam Loading in the ALS Injector Linac  

E-Print Network (OSTI)

to offset the beam loading. ALS Injector Requirements Gun.gun, bunchers, and 50 MeV linac of the ALS injection system.The ALS injector design has been described in previous

Selph, F.

1988-01-01T23:59:59.000Z

265

High Power Superconducting Continuous Wave Linacs for Protons...  

Office of Science (SC) Website

(ANL) Developed in: Current Result of NP research: Spin-off of high power driver linac R&D for the FRIB project Application currently being supported by: DOE Office of Nuclear...

266

Acceleration Mechanisms  

E-Print Network (OSTI)

Glossary I. Background and context of the subject II. Stochastic acceleration III. Resonant scattering IV. Diffusive shock acceleration V. DSA at multiple shocks VI. Applications of DSA VII. Acceleration by parallel electric fields VIII. Other acceleration mechanisms IX. Future directions X. Appendix: Quasilinear equations XI. Bibliography

Melrose, D B

2009-01-01T23:59:59.000Z

267

Adjustable permanent quadrupoles for the next linear collider  

Science Conference Proceedings (OSTI)

The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 138 Tesla, with a maximum gradient of 141 Tesla per meter, an adjustment range of +0 to {minus}20% and effective lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micron during the 20% adjustment. In an effort to reduce costs and increase reliability, several designs using hybrid permanent magnets have been developed. Four different prototypes have been built. All magnets have iron poles and use Samarium Cobalt to provide the magnetic fields. Two use rotating permanent magnetic material to vary the gradient, one uses a sliding shunt to vary the gradient and the fourth uses counter rotating magnets. Preliminary data on gradient strength, temperature stability, and magnetic center position stability are presented. These data are compared to an equivalent electromagnetic prototype.

James T. Volk et al.

2001-06-22T23:59:59.000Z

268

SNS/BNL Accelerator Physics Group page  

NLE Websites -- All DOE Office Websites (Extended Search)

SNS/BNL Accelerator Systems group SNS/BNL Accelerator Systems group CA-Department Bldg 817 Upton, NY 11973, USA The Spallation Neutron Source project is a collaboration between six national laboratories of the United states to build a MegaWatt neutrons source driven by a proton accelerator. The complex is going to be build in Oak Ridge (Tennessee) and consists of a full energy (1GeV) linac, an accumulator ring and a mercury target with several instruments for neutron scattering. All the information in the project can be found here. At Brookhaven national laboratory we work mainly in the accumulator ring and transfer lines. Our group is part or the Collider Accelerator Division also in charge of RHIC and the AGS complex. If you are looking for information in a particular topic you can contact the persons working on

269

The rare isotope accelerator (RIA) facility project  

DOE Green Energy (OSTI)

The envisioned Rare-Isotope Accelerator (RIA) facility would add substantially to research opportunities for nuclear physics and astrophysics by combining increased intensities with a greatly expanded variety of high-quality rare-isotope beams. A flexible superconducting driver linac would provide 100 kW, 400 MeV/nucleon beams of any stable isotope from hydrogen to uranium onto production targets. Combinations of projectile fragmentation, target fragmentation, fission, and spallation would produce the needed broad assortment of short-lived secondary beams. This paper describes the project's background, purpose, and status, the envisioned facility, and the key subsystem, the driver linac. RIA's scientific purposes are to advance current theoretical models, reveal new manifestations of nuclear behavior, and probe the limits of nuclear existence [3]. Figures 1 and 2 show, respectively, examples of RIA research opportunities and the yields projected for pursuing them. Figure 3 outlines a conceptual approach for delivering the needed beams.

Christoph Leemann

2000-08-01T23:59:59.000Z

270

Panel discussion on laboratory accelerator programs: present and future  

SciTech Connect

The present SLAC accelerator program is summarized briefly, and the future of electron-positron colliders is discussed. Present activities discussed include the PEP storage ring, the SPEAR storage ring, the Linear Accelerator, and the SLAC Linear Collider (SLC) project. Future prospects include a larger scale linear collider. The stability requirements on acceleration are briefly discussed. (LEW)

Richter, B.

1986-09-01T23:59:59.000Z

271

ACCELERATED LINEARIZED BREGMAN METHOD June 21, 2011 ...  

E-Print Network (OSTI)

Jun 21, 2011... 10-16571, ONR. Grants N00014-03-0514 and N00014-08-1-1118, and DOE Grants DE-FG01-92ER-25126 and DE-FG02-08ER-25856. 1 ...

272

H- Beam Loss and Evidence for Intrabeam Stripping in the LANSCE Linac  

SciTech Connect

The LANSCE accelerator complex is a multi-beam, multi-user facility that provides high-intensity H{sup +} and H{sup -} particle beams for a variety of user programs. At the heart of the facility is a room temperature linac that is comprised of 100-MeV drift tube and 800-MeV coupled cavity linac (CCL) structures. Although both beams are similar in intensity and emittance at 100 MeV, the beam-loss monitors along the CCL show a trend of increased loss for H{sup -} that is not present for H{sup +}. This difference is attributed to stripping mechanisms that affect H{sup -} and not H{sup +}. We present the results of an analysis of H{sup -} beam loss along the CCL that incorporates beam spill measurements, beam dynamics simulations, analytical models and radiation transport estimates using the MCNPX code. The results indicate a significant fraction of these additional losses result from intrabeam stripping.

Rybarcyk, Lawrence J. [Los Alamos National Laboratory; Kelsey, Charles T. IV [Los Alamos National Laboratory; McCrady, Rodney C. [Los Alamos National Laboratory; Pang, Xiaoying [Los Alamos National Laboratory

2012-05-15T23:59:59.000Z

273

The hot prototype of the Pi-mode structure for LINAC4  

E-Print Network (OSTI)

The PIMS (Pi-Mode-Structure) cavities for Linac4 are made of 7 coupled cells operating in !-mode at a frequency of 352 MHz. The mechanical concept is derived from the 5-cell cavities used in the LEP machine, whereas cell length and coupling are adapted for proton acceleration in the range from 50 to 160 MeV. Linac4 will be the first machine to employ this type of cavities for low-beta protons. During the first years of operation the PIMS will be used at low duty cycle (0.1%) as part of the consolidated LHC proton injector complex. It is designed, however, to operate eventually in a high duty cycle (10%) proton injector, which could be used as proton front-end for neutrino or RIB applications. To prepare for the series construction of the 12 PIMS units the first cavity (102 MeV beam energy) has been designed and constructed at CERN, to be used as a hot prototype for RF tests and as a pre-series mechanical unit. In this paper we report on some of the design features, the construction experience, and first measu...

Gerigk, F; Bourquin, P; Dallocchio, A; Favre, G; Geisser, J M; Gentini, L; Giguet, J M; Mathot, S; Polini, M; Pugnat, D; Riffaud, B; Sgobba, S; Tardy, T; Ugena Tirado, P; Vretenar, M

2010-01-01T23:59:59.000Z

274

ORELA accelerator facility  

NLE Websites -- All DOE Office Websites (Extended Search)

The Oak Ridge Electron Linear Accelerator The Oak Ridge Electron Linear Accelerator Pulsed Neutron Source The ORELA is a powerful electron accelerator-based neutron source located in the Physics Division of Oak Ridge National Laboratory. It produces intense, nanosecond bursts of neutrons, each burst containing neutrons with energies from 10e-03 to 10e08 eV. ORELA is operated about 1200 hours per year and is an ORNL User Facility open to university, national laboratory and industrial scientists. The mission of ORELA has changed from a recent focus on applied research to nuclear astrophysics. This is an area in which ORELA has historically been very productive: most of the measurements of neutron capture cross sections necessary for understanding heavy element nucleosynthesis through the slow neutron capture process (s-process) have

275

Comparison of electric and magnetic quadrupole focusing for the low energy end of an induction-linac-ICF (Inertial-Confinement-Fusion) driver  

SciTech Connect

This report compares two physics designs of the low energy end of an induction linac-ICF driver: one using electric quadrupole focusing of many parallel beams followed by transverse combining; the other using magnetic quadrupole focusing of fewer beams without beam combining. Because of larger head-to-tail velocity spread and a consequent rapid current amplification in a magnetic focusing channel, the overall accelerator size of the design using magnetic focusing is comparable to that using electric focusing.

Kim, C.H.

1987-04-01T23:59:59.000Z

276

Accelerator and Beam Science, ABS, Accelerator Operations and Technology,  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerator Concepts Accelerator Concepts Injectors Operations Physics CONTACTS Group Leader Robert Garnett Deputy Group Leader Kenneth Johnson Office Administrator Monica Sanchez Phone: (505) 667-2846 Put a short description of the graphic or its primary message here Accelerator and Beam Science The Accelerator and Beam Science (AOT-ABS) Group at Los Alamos addresses physics aspects of the driver accelerator for the LANSCE spallation neutron source and related topics. These activities are wide ranging and include generating negative and positive ions in plasma ion sources, creating ion beams from these particles, accelerating the ion beams in linear accelerator structures up to an energy of 800 MeV, compressing the negative hydrogen beam to packets of sub-microsecond duration and accumulating beam current in the Proton Storage Ring, and

277

#LabChat: Particle Accelerators, Lasers and Discovery Science, May 17 at  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Particle Accelerators, Lasers and Discovery Science, May Particle Accelerators, Lasers and Discovery Science, May 17 at 1pm EST #LabChat: Particle Accelerators, Lasers and Discovery Science, May 17 at 1pm EST May 15, 2012 - 2:03pm Addthis SLAC’s linac accelerates very short pulses of electrons to 99.9999999 percent the speed of light through a slalom that causes the electrons to emit X-rays, which become synchronized as they interact with the electron pulses and create the world’s brightest X-ray laser pulse. | Photo by Brad Plummer, SLAC. SLAC's linac accelerates very short pulses of electrons to 99.9999999 percent the speed of light through a slalom that causes the electrons to emit X-rays, which become synchronized as they interact with the electron pulses and create the world's brightest X-ray laser pulse. | Photo by

278

Thomas Jefferson National Accelerator Facility Site Tour - Accelerator Map  

NLE Websites -- All DOE Office Websites (Extended Search)

Counting House Free Electron Accelerator Facility Machine Control Center Physics Storage Building North Linear Accelerator South Linear Accelerator VEPCO Substation Machine Control Center Annex Machine Control Center Annex II North Access Building South Access Building Central Helium Liquefier Injector Hall A Truck Ramp Hall B Truck Ramp Hall C Truck Ramp Experimental Hall A Experimental Hall B Experimental Hall C East Arc West Arc Counting House Free Electron Accelerator Facility Machine Control Center Physics Storage Building North Linear Accelerator South Linear Accelerator VEPCO Substation Machine Control Center Annex Machine Control Center Annex II North Access Building South Access Building Central Helium Liquefier Injector Hall A Truck Ramp Hall B Truck Ramp Hall C Truck Ramp Experimental Hall A Experimental Hall B Experimental Hall C East Arc West Arc Science Education Jefferson Lab Jefferson Lab Home Search Jefferson Lab Contact Jefferson Lab Science Education Home Teacher Resources Student Zone Games and Puzzles Science Cinema Programs and Events Search Education Privacy and Security Notice Jefferson Lab Site Tour Guided Tour Site Map Accelerator Area Map Administrative Area Map Tour Index

279

Design Optimization for an X-Ray Free Electron Laser Driven by SLAC Linac  

E-Print Network (OSTI)

FREE ELECTRON LASER DRIVEN BY SLAC LINAC Ming Xie, LawrenceLaser (FEL) driven by the SLAC linac. The study assumes theis carried out for the SLAC FEL over all independent system

Xie, Ming

1994-01-01T23:59:59.000Z

280

High Power Superconducting Continuous Wave Linacs for Protons and  

Office of Science (SC) Website

Power Superconducting Continuous Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives High Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: High Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

DIAGNOSTIC TOOLS FOR BEAM HALO INVESTIGATION IN SNS LINAC  

Science Conference Proceedings (OSTI)

Uncontrolled beam loss is a major concern in the operation of a high intensity hadron linac. A low density cloud of particles with large oscillation amplitudes, so called halo, can form around the dense regular beam core. This halo can be a direct or indirect cause of beam loss. There is experimental evidence of halo growing in the SNS linac and limiting the further reduction of beam loss. A set of tools is being developed for detecting of the halo and investigating its origin and dynamics. The set includes high resolution emittance measurements in the injector, laser based emittance measurements at 1 GeV, and high resolution profile measurements along the linac. We will present our experience with useful measurement techniques and data analysis algorithms.

Aleksandrov, Alexander V [ORNL; Blokland, Willem [ORNL; Liu, Yun [ORNL; Long, Cary D [ORNL; Zhukov, Alexander P [ORNL

2012-01-01T23:59:59.000Z

282

A New Control Room for SLAC Accelerators  

SciTech Connect

We are planning to construct a new control room at SLAC to unify and improve the operation of the LCLS, SPEAR3, and FACET accelerator facilities, and to provide the space and flexibility needed to support the LCLS-II and proposed new test beam facilities. The existing control rooms for the linac and SPEAR3 have been upgraded in various ways over the last decade, but their basic features have remained unchanged. We propose to build a larger modern Accelerator Control Room (ACR) in the new Research Support Building (RSB) which is currently under construction at SLAC. Shifting the center of control for the accelerator facilities entails both technical and administrative challenges. In this paper, we describe the history, concept, and status of this project.

Erickson, Roger; Guerra, E.; Stanek, M.; Hoover, Z.Van; Warren, J.; /SLAC

2012-06-04T23:59:59.000Z

283

BEAM SIMULATIONS USING VIRTUAL DIAGNOSTICS FOR THE DRIVER LINAC  

Science Conference Proceedings (OSTI)

End-to-end beam simulations for the driver linac have shown that the design meets the necessary performance requirements including having adequate transverse and longitudinal acceptances. However, to achieve reliable operational performance, the development of appropriate beam diagnostic systems and control room procedures are crucial. With limited R&D funding, beam simulations provide a cost effective tool to evaluate candidate beam diagnostic systems and to provide a critical basis for developing early commissioning and later operational activities. We propose to perform beam dynamic studies and engineering analyses to define the requisite diagnostic systems of the driver linac and through simulation to develop and test commissioning and operational procedures.

R. C. York; X. Wu; Q. Zhao

2011-12-21T23:59:59.000Z

284

LINAC BEAM DYNAMICS SIMULATIONS WITH PY-ORBIT  

Science Conference Proceedings (OSTI)

Linac dynamics simulation capabilities of the PyORBIT code are discussed. PyORBIT is an open source code and a further development of the original ORBIT code that was created and used for design, studies, and commissioning of the SNS ring. The PyORBIT code, like the original one, has a two-layer structure. C++ is used to perform time-consuming computations, and the program flow is controlled from a Python language shell. The flexible structure makes it possible to use PyORBIT also for linac dynamics simulations. A benchmark of PyORBIT with Parmila and the XAL Online model is presented.

Shishlo, Andrei P [ORNL

2012-01-01T23:59:59.000Z

285

FEL-accelerator related diagnostics  

SciTech Connect

Free Electron Lasers (FEL) present a unique set of beam parameters to the diagnostics suite. The FEL requires characterization of the full six dimensional phase space of the electron beam at the wiggler and accurate alignment of the electron beam to the optical mode of the laser. In addition to the FEL requirements on the diagnostics suite, the Jefferson Lab FEL is operated as an Energy Recovered Linac (ERL) which imposes additional requirements on the diagnostics. The ERL aspect of the Jefferson Lab FEL requires that diagnostics operate over a unique dynamic range and operate with simultaneous transport of the accelerated and energy recovered beams. This talk will present how these challenges are addressed at the Jefferson Lab FEL.

Kevin Jordan; David Douglas; Stephen V. Benson; Pavel Evtuschenko

2007-08-02T23:59:59.000Z

286

Accelerator Need  

NLE Websites -- All DOE Office Websites (Extended Search)

Need for Large Accelerators An Article Written Originally for Midlevel Teachers Back In order to study small particles, a high energy beam of particles must be generated. The...

287

USING THE ONLINE SINGLE PARTICLE MODEL FOR SNS ACCELERATOR TUNING  

Science Conference Proceedings (OSTI)

This paper describes the usage of the XAL online model for transverse and longitudinal tuning of the SNS linac. Most of the SNS control room physics applications are based on the XAL online model, which can be synchronized with an accelerator live state and used to tune the machine. Advantages of a simple and fast single particle model for orbit correction and longitudinal dynamics control in the SNS control room are discussed.

Shishlo, Andrei P [ORNL; Aleksandrov, Alexander V [ORNL

2008-01-01T23:59:59.000Z

288

Status of Hybrid Target R&D at KEK LINAC  

E-Print Network (OSTI)

A hybrid positron source, consisting of a crystal as electron to photon converter and a amorphous target, is a candidate to relax heat load problem for high intensity positron sources. In this article we report status of experimental study using the 8 GeV electron beam at KEKB LINAC.

Tohru Takahashi

2012-02-27T23:59:59.000Z

289

SLAC National Accelerator Laboratory - Accelerators and Society  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerators and Society PHOTO: An accelerator at SLAC. SLAC has been developing, running and studying the basic physics of particle accelerators for half a century. Thousands of...

290

SLAC National Accelerator Laboratory - Accelerator Directorate  

NLE Websites -- All DOE Office Websites (Extended Search)

physics. Today, the Accelerator Directorate operates and maintains SLAC's existing accelerators to provide the highest possible level of performance. Accelerator employees improve...

291

Muon Acceleration in Cosmic-ray Sources  

E-Print Network (OSTI)

Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in Gamma-Ray Bursts magnetars, or other sources. These source models require very high accelerating gradients, $10^{13}$ keV/cm, with the minimum gradient set by the length of the source. At gradients above 1.6 keV/cm, muons produced by hadronic interactions undergo significant acceleration before they decay. This acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. We rule out many models of linear acceleration, setting strong constraints on plasma wakefield accelerators and on models for sources like Gamma Ray Bursts and magnetars.

Spencer R. Klein; Rune Mikkelsen; Julia K. Becker Tjus

2012-08-09T23:59:59.000Z

292

ANNUAL REPORT ACCELERATOR DIVISION  

E-Print Network (OSTI)

the facility is LBL and SLAC. The six-sided sto- the end ofstorage ring at in SLAC. ',hich colI ide The two-mile-longActual work began with the SLAC linac The contract involved

Authors, Various

2011-01-01T23:59:59.000Z

293

H- AND PROTON BEAM LOSS COMPARISON AT SNS SUPERCONDUCTING LINAC  

Science Conference Proceedings (OSTI)

A comparison of beam loss in the superconducting part (SCL) of the Spallation Neutron Source (SNS) linac for H- and protons is presented. During the experiment the nominal beam of negative hydrogen ions in the SCL was replaced by a proton beam created by insertion of a thin stripping carbon foil placed in the low energy section of the linac. The observed significant reduction in the beam loss for protons is explained by a domination of the intra beam stripping mechanism of the beam loss for H-. The details of the experiment are discussed, and a preliminary estimation of the cross section of the reaction H- + H- -> H- + H0 + e is presented. Earlier, a short description of these studies was presented in [1].

Aleksandrov, Alexander V [ORNL; Galambos, John D [ORNL; Plum, Michael A [ORNL; Shishlo, Andrei P [ORNL

2012-01-01T23:59:59.000Z

294

BEAM POSITION AND PHASE MONITORS FOR THE LANSCE LINAC  

SciTech Connect

New beam-position and phase monitors are under development for the linac at the Los Alamos Neutron Science Center (LANSCE). Transducers have been designed and are being fabricated. We are considering many options for the electronic instrumentation to process the signals and provide position and phase data with the necessary precision and flexibility to serve the various required functions. We'll present the various options under consideration for instrumentation along with the advantages and shortcomings of these options.

McCrady, Rodney C. [Los Alamos National Laboratory; Gilpatrick, John D. [Los Alamos National Laboratory; Power, John F. [AOT-IC

2011-01-01T23:59:59.000Z

295

HIGH DYNAMIC-RANGE HIGH SPEED LINAC CURRENT MEASUREMENTS  

SciTech Connect

It is desired to measure the linac current of a charged particle beam with a consistent accuracy over a dynamic range of over 120 dB. Conventional current transformers suffer from droop, can be susceptible to electromagnetic interference (EMI), and can be bandwidth limited. A novel detector and electronics were designed to maximize dynamic range of about 120 dB and measure rise-times on the order of 10 nanoseconds.

Deibele, Craig Edmond [ORNL; Curry, Douglas E [ORNL; Dickson, Richard W [ORNL

2012-01-01T23:59:59.000Z

296

BEAM POSITION AND PHASE MONITORS FOR THE LANSCE LINAC  

Science Conference Proceedings (OSTI)

New beam-position and phase monitors are under development for the linac at the Los Alamos Neutron Science Center (LANSCE.) Transducers have been designed and are being installed. We are considering many options for the electronic instrumentation to process the signals and provide position and phase data with the necessary precision and flexibility to serve the various required functions. We'll present the various options under consideration for instrumentation along with the advantages and shortcomings of these options.

McCrady, Rodney C. [Los Alamos National Laboratory; Gilpatrick, John D. [Los Alamos National Laboratory; Watkins, Heath A. [Los Alamos National Laboratory

2012-04-11T23:59:59.000Z

297

The Linac Injector For The ANL 7 Ge V Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

Injector For The ANL 7 Ge V Injector For The ANL 7 Ge V Advanced Photon Source A. Nassiri, W. Wesolowski, and G. Mavrogenes Argonne National Laboratory Submitted to the 1990 LINAC Conferece Albuquerque, New Mexico LS-154 9/28/90 TEE LINAC INJECTOR FOR TEE ANL 7 G<.iJ,V ADVANCED PHOTON SOORCE* A. Nassiri, W. Wesolowski, and G. Mavrogenes Argonne National Laboratory 9700 South Cass Avenue Argonne, IL 60439 USA Abstract The Argonne Advanced Photon Source (APS) linac system consists of a 200 MeV electron linac, a positron converter, and a 450 MeV positron linac. Design parameters and computer simulations of the two linac systems are presented. Introduction The Argonne Advanced Photon Source is a 7 GeV synchrotron X-Ray facility. The APS machine parameters have been described.

298

Application Acceleration  

NLE Websites -- All DOE Office Websites (Extended Search)

Acceleration Acceleration on Current and Future Cray Platforms Alice Koniges, Robert Preissl, Jihan Kim, Lawrence Berkeley National Laboratory David Eder, Aaron Fisher, Nathan Masters, Velimir Mlaker, Lawrence Livermore National Laboratory Stephane Ethier, Weixing Wang, Princeton Plasma Physics Laboratory Martin Head-Gordon, University of California, Berkeley and Nathan Wichmann, Cray Inc. ABSTRACT: Application codes in a variety of areas are being updated for performance on the latest architectures. We describe current bottlenecks and performance improvement areas for applications including plasma physics, chemistry related to carbon capture and sequestration, and material science. We include a variety of methods including advanced hybrid parallelization using multi-threaded MPI, GPU acceleration, libraries and auto- parallelization compilers. KEYWORDS: hybrid

299

Superconducting Resonators Development for the FRIB and ReA Linacs at MSU: Recent Achievements and Future Goals  

Science Conference Proceedings (OSTI)

The superconducting driver and post-accelerator linacs of the FRIB project, the large scale radioactive beam facility under construction at MSU, require the construction of about 400 low-{beta} Quarter-wave (QWR) and Half-wave resonators (HWR) with four different optimum velocities. 1st and 2nd generation prototypes of {beta}{sub 0} = 0.041 and 0.085 QWRs and {beta}{sub 0} = 0.53 HWRs have been built and tested, and have more than fulfilled the FRIB and ReA design goals. The present cavity surface preparation at MSU allowed production of low-{beta} cavities nearly free from field emission. The first two cryostats of {beta}{sub 0} = 0.041 QWRs are now in operation in the ReA3 linac. A 3rd generation design of the FRIB resonators allowed to further improve the cavity parameters, reducing the peak magnetic field in operation and increasing the possible operation gradient, with consequent reduction of the number of required resonators. The construction of the cavities for FRIB, which includes three phases for each cavity type (development, pre-production and production runs) has started. Cavity design, construction, treatment and performance will be described and discussed.

Facco, A; Binkowski, J; Compton, C; Crisp, J L; Dubbs, L J; Elliot, K; Harle, L L; Hodek, M; Johnson, M J; Leitner, D; Leitner, M; Malloch, I M; Miller, S J; Oweiss, R; Popielarski, J; Popielarski, L; Saito, K; Wei, J; Wlodarczak, J; Xu, Y; Zhang, Y; Zheng, Z; Burrill, A; Davis, G K; Macha, K

2012-07-01T23:59:59.000Z

300

Optical transition radiation used in the diagnostic of low energy and low current electron beams in particle accelerators  

Science Conference Proceedings (OSTI)

Optical transition radiation (OTR) plays an important role in beam diagnostics for high energy particle accelerators. Its linear intensity with beam current is a great advantage as compared to fluorescent screens, which are subject to saturation. Moreover, the measurement of the angular distribution of the emitted radiation enables the determination of many beam parameters in a single observation point. However, few works deals with the application of OTR to monitor low energy beams. In this work we describe the design of an OTR based beam monitor used to measure the transverse beam charge distribution of the 1.9-MeV electron beam of the linac injector of the IFUSP microtron using a standard vision machine camera. The average beam current in pulsed operation mode is of the order of tens of nano-Amps. Low energy and low beam current make OTR observation difficult. To improve sensitivity, the beam incidence angle on the target was chosen to maximize the photon flux in the camera field-of-view. Measurements that assess OTR observation (linearity with beam current, polarization, and spectrum shape) are presented, as well as a typical 1.9-MeV electron beam charge distribution obtained from OTR. Some aspects of emittance measurement using this device are also discussed.

Silva, T. F.; Bonini, A. L.; Lima, R. R.; Maidana, N. L.; Malafronte, A. A.; Pascholati, P. R.; Vanin, V. R.; Martins, M. N. [Institute of Physics, University of Sao Paulo, CP 66318, 05315-970 Sao Paulo, SP (Brazil)

2012-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

SLAC National Accelerator Laboratory - Shaken, Not Heated: the...  

NLE Websites -- All DOE Office Websites (Extended Search)

Working at the SLAC National Accelerator Laboratory's Linear Coherent Light Source (LCLS), the scientists aimed intense, 130-femtosecond-long pulses of terahertz light at...

302

Linear Collider Collaboration Tech Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

0 0 April 2001 Rev.1 July 2003 Guide to LIBXSIF, a Library for Parsing the Extended Standard Input Format of Accelerated Beamlines Peter G. Tenenbaum Stanford Linear Accelerator Center Stanford University Stanford, CA Abstract: We describe LIBXSIF, a standalone library for parsing the Extended Standard Input Format of accelerator beamlines. Included in the description are: documentation of user commands; full description of permitted accelerator elements and their attributes; the construction of beamline lists; the mechanics of adding LIBXSIF to an existing program; and "under the hood" details for users who wish to modify the library or are merely morbidly curious. Guide to LIBXSIF, a Library for Parsing the Extended Standard Input Format of

303

Experimental studies of multipass beam breakup and energy recovery using the CEBAF injector linac.  

E-Print Network (OSTI)

??Beam breakup (BBU) instabilities in superconducting linacs are a significant issue due to the potentially high Q of the cavity higher-order modes (HOMs). The CEBAF… (more)

Sereno, Nicholas S. R.

1994-01-01T23:59:59.000Z

304

Energy Recovery Linac cavity at BNL | U.S. DOE Office of Science...  

Office of Science (SC) Website

Energy Recovery Linac cavity at BNL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIRSTTR...

305

High Current Energy Recovery Linac at BNL | U.S. DOE Office of...  

Office of Science (SC) Website

High Current Energy Recovery Linac at BNL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIRSTTR...

306

500 MW X-Band RF System of a 0.25 GeV Electron LINAC for Advanced Compton Scattering Source Application  

SciTech Connect

A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL in collaboration with the SLAC National Accelerator Laboratory. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. For compactness consideration, we are looking at a folded waveguide setup. This will give us 500 MW at output of the compressor. The compressed pulse will then be distributed to the RF gun and to six traveling wave accelerator sections. Phase and amplitude control are located at the RF gun input and additional control points along the LINAC to allow for parameter control during operation. This high power RF system is being designed and constructed. In this paper, we will present the design, layout, and status of this RF system.

Chu, Tak Sum; /LLNL, Livermore; Anderson, Scott; /LLNL, Livermore; Barty, Christopher; /LLNL, Livermore; Gibson, David; /LLNL, Livermore; Hartemann, Fred; /LLNL, Livermore; Marsh, Roark; /LLNL, Livermore; Siders, Craig; /LLNL, Livermore; Adolphsen, Chris; /SLAC; Jongewaard, Erik; /SLAC; Raubenheimer, Tor; /SLAC; Tantawi, Sami; /SLAC; Vlieks, Arnold; /SLAC; Wang, Juwen; /SLAC

2012-07-03T23:59:59.000Z

307

500 MW X-BAND RF SYSTEM OF A 0.25 GEV ELECTRON LINAC FOR ADVANCED COMPTON SCATTERING SOURCE APPLICATION  

Science Conference Proceedings (OSTI)

A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL in collaboration with SLAC National Accelerator Laboratory. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. For compactness consideration, we are looking at a folded waveguide setup. This will give us 500 MW at output of the compressor. The compressed pulse will then be distributed to the RF gun and to six traveling wave accelerator sections. Phase and amplitude control are located at the RF gun input and additional control points along the LINAC to allow for parameter control during operation. This high power RF system is being designed and constructed. In this paper, we will present the design, layout, and status of this RF system.

Chu, T S; Anderson, S G; Gibson, D J; Hartemann, F V; Marsh, R A; Siders, C; Barty, C P; Adolphsen, C; Jongewaard, E; Tantawi, S; Vlieks, A; Wang, J W; Raubenheimer, T

2010-05-12T23:59:59.000Z

308

Scientific issues in future induction linac accelerators for heavy ion fusion  

E-Print Network (OSTI)

Miller, M. Tabak, Nuc. Fusion, 39, 883 (1999). [2] S.S. Yu,W.M. Sharp, D.R. Welch, Fusion Science and Technology, 44,Transport for Heavy Ion Fusion", in these proceedings. [18

Celata, C.M.

2004-01-01T23:59:59.000Z

309

Design of an RFQ-based, H/sup -/ injector for the BNL/FNAL 200 MeV proton linacs  

SciTech Connect

An LBL/BNL/FNAL collaboration has been formed to design an RFQ-based Cockcroft-Walton replacement, suitable for use at the Brookhaven and Fermilab 200 MeV proton linacs. A common design for the ion source and the RFQ will result in an economical construction and testing program compatible with both applications. The technical requirements have been evaluated and it appears that they can be satisfied with identical RFQs, capable of accelerating 50 mA of H/sup -/ from 35 to 750 keV, at a nominal frequency of 200 MHz.

Gough, R.A.; Staples, J.; Tanabe, J.; Yee, D.; Howard, D.; Curtis, C.; Prelec, K.

1986-06-01T23:59:59.000Z

310

MUON ACCELERATION  

Science Conference Proceedings (OSTI)

One of the major motivations driving recent interest in FFAGs is their use for the cost-effective acceleration of muons. This paper summarizes the progress in this area that was achieved leading up to and at the FFAG workshop at KEK from July 7-12, 2003. Much of the relevant background and references are also given here, to give a context to the progress we have made.

BERG,S.J.

2003-11-18T23:59:59.000Z

311

What is an accelerator?  

NLE Websites -- All DOE Office Websites (Extended Search)

world of physics though, 'accelerator' means something a little more specific. Our accelerators are a whole class of machines that accelerate atoms, or more often, pieces of...

312

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Argonne Accelerator Institute: Mission The mission of the Argonne Accelerator Institute is centered upon the following related goals: Locate next generation accelerator facilities...

313

Broad-band chopper for a CW proton linac at Fermilab  

SciTech Connect

The future Fermilab program in the high energy physics is based on a new facility called the Project X [1] to be built in the following decade. It is based on a 3 MW CW linear accelerator delivering the 3 GeV 1 mA H{sup -} beam to a few experiments simultaneously. Small fraction of this beam will be redirected for further acceleration to 8 GeV to be injected to the Recycler/Main Injector for a usage in a neutrino program and other synchrotron based high energy experiments. Requirements and technical limitations to the bunch-by-bunch chopper for the Fermilab Project X are discussed.

Gianfelice-Wendt, E.; Lebedev, V.A.; Solyak, N.; Nagaitsev, S.; Sun, D.; /Fermilab

2011-03-01T23:59:59.000Z

314

An Overview of near-field vs. far-field radiation characteristics of the Linac Coherent Light Sources (LCLS)  

E-Print Network (OSTI)

An Overview of near-field vs. far-field radiation characteristics of the Linac Coherent Light Sources (LCLS)

Tatchyn, R

2005-01-01T23:59:59.000Z

315

SLAC National Accelerator Laboratory - Accelerator Research  

NLE Websites -- All DOE Office Websites (Extended Search)

An image of the FACET equipment and a man examining it. ACCELERATOR PHYSICS Accelerators form the backbone of SLAC's on-site experimental program. They are complicated...

316

Accelerators and the Accelerator Community  

Science Conference Proceedings (OSTI)

In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

Malamud, Ernest; Sessler, Andrew

2008-06-01T23:59:59.000Z

317

Characterisation of electron beams from laser-driven particle accelerators  

Science Conference Proceedings (OSTI)

The development, understanding and application of laser-driven particle accelerators require accurate measurements of the beam properties, in particular emittance, energy spread and bunch length. Here we report measurements and simulations showing that laser wakefield accelerators can produce beams of quality comparable to conventional linear accelerators.

Brunetti, E.; Manahan, G. G.; Shanks, R. P.; Islam, M. R.; Ersfeld, B.; Anania, M. P.; Cipiccia, S.; Issac, R. C.; Vieux, G.; Welsh, G. H.; Wiggins, S. M.; Jaroszynski, D. A. [Physics Department, University of Strathclyde, Glasgow G4 0NG (United Kingdom)

2012-12-21T23:59:59.000Z

318

Recent Developments on ALICE (Accelerators and Lasers In Combined Experiments) at Daresbury Laboratory  

SciTech Connect

Progress made in ALICE (Accelerators and Lasers In Combined Experiments) commissioning and a summary of the latest experimental results are presented in this paper. After an extensive work on beam loading effects in SC RF linac (booster) and linac cavities conditioning, ALICE can now operate in full energy recovery mode at the bunch charge of 40pC, the beam energy of 30MeV and train lengths of up to 100us. This improved operation of the machine resulted in generation of coherently enhanced broadband THz radiation with the energy of several tens of uJ per pulse and in successful demonstration of the Compton Backscattering x-ray source experiment. The next steps in the ALICE scientific programme are commissioning of the IR FEL and start of the research on the first non-scaling FFAG accelerator EMMA. Results from both projects will be also reported.

Saveliev, Y M; Buckley, R K; Buckley, S R; Clarke, J A; Corlett, P A; Dunning, D J; Goulden, A R; Hill, S F; Jackson, F; Jamison, S P; Jones, J K; Jones, L B; Leonard, S; McIntosh, P A; McKenzie, J W; Middleman, K J; Militsyn, B L; Moss, A J; Muratori, B D; Orrett, J F; Pattalwar, S M; Phillips, P J; Scott, D J; Seddon, E A; Shepherd, B.J.A.; Smith, S L; Thompson, N; Wheelhouse, A E; Williams, P H; Harrison, P; Holder, D J; Holder, G M; Schofield, A L; Weightman, P; Williams, R L; Laundry, D; Powers, T; Priebe, G

2010-05-01T23:59:59.000Z

319

LCC-0023 cover.PDF  

NLE Websites -- All DOE Office Websites (Extended Search)

3 31/08/99 3 31/08/99 Matching Program for the NLC Main Linac August 31, 1999 Yuri Nosochkov, Tor Raubenheimer and Mark Woodley Stanford Linear Accelerator Center Stanford, California Abstract: In this note, we describe the computer code used to design the NLC main linac optics, and present the current parameters of the linac lattice. Matching Program for the NLC Main Linac Yuri Nosochkov, Tor Raubenheimer and Mark Woodley Stanford Linear Accelerator Center, Stanford University, Stanford, CA 94309 Abstract In this note, we describe the computer code used to design the NLC main linac optics, and present the current parameters of the linac lattice. 1 Introduction The two main components of the linac are accelerator structures for beam acceleration and quadru- poles for transverse focusing. Most of the NLC linac length is occupied by the accelerator

320

Accelerating Solutions  

NLE Websites -- All DOE Office Websites (Extended Search)

Solutions From vehicles on the road to the energy that powers them, Oak Ridge National Laboratory innovations are advancing American transportation. Oak Ridge National Laboratory is making an impact on everyday America by enhancing transportation choices and quality of life. Through strong collaborative partnerships with industry, ORNL research and development efforts are helping accelerate the deployment of a new generation of energy efficient vehicles powered by domestic, renewable, clean energy. EPA ultra-low sulfur diesel fuel rule ORNL and the National Renewable Energy Laboratory co-led a comprehensive research and test program to determine the effects of diesel fuel sulfur on emissions and emission control (catalyst) technology. In the course of this program, involving

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Comparison of accelerator technologies for use in ADSS  

SciTech Connect

Accelerator Driven Subcritical (ADS) fission is an interesting candidate basis for nuclear waste transmutation and for nuclear power generation. ADS can use either thorium or depleted uranium as fuel, operate below criticality, and consume rather than produce long-lived actinides. A case study with a hypothetical, but realistic nuclear core configuration is used to evaluate the performance requirements of the driver proton accelerator in terms of beam energy, beam current, duty factor, beam distribution delivered to the fission core, reliability, and capital and operating cost. Comparison between a CW IC and that of a SRF proton linac is evaluated. Future accelerator R&D required to improve each candidate accelerator design is discussed. ADS fission has interesting potential for electric power generation and also for destruction of long-lived actinide waste produced by conventional critical reactors. ADS systems offer several interesting advantages in comparison to critical reactors: (1) ADS provides greater flexibility for the composition and placement of fissile, fertile, or fission product waste within the core, and require less enrichment of fissile content; (2) The core can be operated with a reactivity k{sub eff} that cannot reach criticality by any failure mode; (3) When the beam is shut off fission ceases in the core; (4) Coupling the fast neutron spectrum of the spallation drive to fast core neutronics offers a basis for more complete burning of long-lived actinides; and (5) ADS designs can provide sufficient thermal mass that meltdown cannot occur from radioactive heat after fission is stopped. In order to drive a {approx}GW{sub e} fission core a CW proton beam of >700 MeV and {approx}15 MW beam power is required. A previous study of the accelerator performance required for ADS systems concluded that present accelerator performance is approaching those requirements, but accelerator system cost and reliability remain particular concerns. The obvious candidates for accelerators that can provide intense CW proton beams are isochronous cyclotrons (IC) and superconducting linacs. We have examined a case study using a hypothetical ADS core configuration to guide our thinking in evaluating those two accelerator technologies for use in ADS systems. Issues of accelerator power, multiplicity of accelerators, and options for core neutronics and fuel form are discussed.

Weng, W.T.; Ludewig, H.; Raparia, D.; Trbojevic, D.; Todosow, M.; McIntyre, P.; Sattarov, A.

2011-03-28T23:59:59.000Z

322

EA-1904: Final Environmental Assessment | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Environmental Assessment EA-1904: Final Environmental Assessment Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, CA This EA evaluates the...

323

EA-1904: Finding of No Significant Impact | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

No Significant Impact EA-1904: Finding of No Significant Impact Linac Coherent Light Source II at Stanford Linear Accelerator Laboratory, San Mateo, CA Based on the findings in...

324

EA-1426: Finding of No Significant Impact | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

of No Significant Impact EA-1426: Finding of No Significant Impact Linac Coherent Light Source Project, Stanford Linear Accelerator Center, Menlo Park, California The DOE...

325

LCC-0024 cover.PDF  

NLE Websites -- All DOE Office Websites (Extended Search)

4 11.10.99 Comparison of Lattice Options for the NLC Main Linac November 11, 1999 Y. Nosochkov & T. O. Raubenheimer Stanford Linear Accelerator Center Stanford, California...

326

CX-009096: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

of Energy (DOE) Pacific Northwest Site Office (PNSO) proposes to perform testing of radiation detection equipment using a portable linear accelerator (LINAC) at the Pacific...

327

Audit Letter Report: OAS-L-07-04  

Energy.gov (U.S. Department of Energy (DOE))

Inquiry to the Hotline Complaint on Possible Design Mistakes and Cost Overruns of the Linac Coherent Light Source Project at Stanford Linear Accelerator Center

328

A-1 1999 SITE ENVIRONMENTAL REPORT APPENDIX A: GLOSSARY  

E-Print Network (OSTI)

hours LED light emitting diode LIE Long Island Expressway LINAC Linear Accelerator MBtu thousand British,1,1-trichloroethane TCE trichloroethylene TCLP toxicity characteristic leaching procedure TLD thermoluminescent

Homes, Christopher C.

329

Linear Quadratic  

E-Print Network (OSTI)

The proposal of Reshef et. al. (“MIC”) is an interesting new approach for discovering non-linear dependencies among pairs of measurements in exploratory data mining. However, it has a potentially serious drawback. The authors laud the fact that MIC has no preference for some alternatives over others, but as the authors know, there is no free lunch in Statistics: tests which strive to have high power against all alternatives can have low power in many important situations. To investigate this, we ran simulations to compare the power of MIC to that of standard Pearson correlation and distance correlation (dcor) Székely & Rizzo (2009). We simulated pairs of variables with different relationships (most of which were considered by the Reshef et. al.), but with varying levels of noise added. To determine proper cutoffs for testing the independence hypothesis, we simulated independent data with the appropriate marginals. As one can see from the Figure, MIC has lower power than dcor, in every case except the somewhat pathological

Noah Simon; Robert Tibshirani; Noah Simon; Robert Tibshirani

2011-01-01T23:59:59.000Z

330

Energy recovery linacs in high-energy and nuclear physics  

Science Conference Proceedings (OSTI)

Energy Recovery Linacs (ERL) have significant potential uses in High Energy Physics and Nuclear Physics. We describe some of the potential applications which are under development by our laboratories in this area and the technology issues that are associated with these applications. The applications that we discuss are electron cooling of high-energy hadron beams and electron-nucleon colliders. The common issues for some of these applications are high currents of polarized electrons, high-charge and high-current electron beams and the associated issues of High-Order Modes. The advantages of ERLs for these applications are numerous and will be outlined in the text. It is worth noting that some of these advantages are the high-brightness of the ERL beams and their relative immunity to beam-beam disturbances.

I. Ben-Zvi; Ya. Derbenev; V. Litvinenko; L. Merminga

2005-03-01T23:59:59.000Z

331

Direct High-Power Laser Acceleration of Ions for Medical Applications  

Science Conference Proceedings (OSTI)

Theoretical investigations show that linearly and radially polarized multiterawatt and petawatt laser beams, focused to subwavelength waist radii, can directly accelerate protons and carbon nuclei, over micron-size distances, to the energies required for hadron cancer therapy. Ions accelerated by radially polarized lasers have generally a more favorable energy spread than those accelerated by linearly polarized lasers of the same intensity.

Salamin, Yousef I. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Physics Department, American University of Sharjah, POB 26666, Sharjah (United Arab Emirates); Harman, Zoltan; Keitel, Christoph H. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany)

2008-04-18T23:59:59.000Z

332

Energy Recovery Linac cavity at BNL | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Energy Recovery Linac cavity at BNL Energy Recovery Linac cavity at BNL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Energy Recovery Linac cavity at BNL Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Energy Recovery Linac cavity Developed at: Brookhaven National Laboratory, New York and Advanced Energy Systems, New York Developed in:

333

High Current Energy Recovery Linac at BNL | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

High Current Energy Recovery Linac at High Current Energy Recovery Linac at BNL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives High Current Energy Recovery Linac at BNL Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: High Current Energy Recovery Linac Developed at: Brookhaven National Laboratory, New York and Advanced Energy Systems, New

334

Summary of sessions B and F: High intensity linacs and frontend & proton drivers  

SciTech Connect

This paper summarizes the sessions B&F of the 33rd ICFA Advanced Beam Dynamics Workshop on High Intensity & High Brightness Hadron Beams held in Bensheim, Germany. It covers high intensity linacs, front ends and proton driver topics.

Ferdinand, R.; /Saclay; Chou, W.; /Fermilab; Galambos, J.; /Oak Ridge

2005-01-01T23:59:59.000Z

335

IRIDE White Book, An Interdisciplinary Research Infrastructure based on Dual Electron linacs&lasers  

E-Print Network (OSTI)

This report describes the scientific aims and potentials as well as the preliminary technical design of IRIDE, an innovative tool for multi-disciplinary investigations in a wide field of scientific, technological and industrial applications. IRIDE will be a high intensity 'particle factory', based on a combination of a high duty cycle radio-frequency superconducting electron linac and of high energy lasers. Conceived to provide unique research possibilities for particle physics, for condensed matter physics, chemistry and material science, for structural biology and industrial applications, IRIDE will open completely new research possibilities and advance our knowledge in many branches of science and technology. IRIDE will contribute to open new avenues of discoveries and to address most important riddles: What does matter consist of? What is the structure of proteins that have a fundamental role in life processes? What can we learn from protein structure to improve the treatment of diseases and to design more efficient drugs? But also how does an electronic chip behave under the effect of radiations? How can the heat flow in a large heat exchanger be optimized? The scientific potential of IRIDE is far reaching and justifies the construction of such a large facility in Italy in synergy with the national research institutes and companies and in the framework of the European and international research. It will impact also on R&D work for ILC, FEL, and will be complementarity to other large scale accelerator projects. IRIDE is also intended to be realized in subsequent stages of development depending on the assigned priorities.

D. Alesini; M. Alessandroni; M. P. Anania; S. Andreas; M. Angelone; A. Arcovito; F. Arnesano; M. Artioli; L. Avaldi; D. Babusci; A. Bacci; A. Balerna; S. Bartalucci; R. Bedogni; M. Bellaveglia; F. Bencivenga; M. Benfatto; S. Biedron; V. Bocci; M. Bolognesi; P. Bolognesi; R. Boni; R. Bonifacio; M. Boscolo; F. Boscherini; F. Bossi; F. Broggi; B. Buonomo; V. Calo'; D. Catone; M. Capogni; M. Capone; M. Castellano; A. Castoldi; L. Catani; G. Cavoto; N. Cherubini; G. Chirico; M. Cestelli-Guidi; E. Chiadroni; V. Chiarella; A. Cianchi; M. Cianci; R. Cimino; F. Ciocci; A. Clozza; M. Collini; G. Colo'; A. Compagno; G. Contini; M. Coreno; R. Cucini; C. Curceanu; S. Dabagov; E. Dainese; I. Davoli; G. Dattoli; L. De Caro; P. De Felice; S. Della Longa; G. Delle Monache; M. De Spirito; A. Di Cicco; C. Di Donato; D. Di Gioacchino; D. Di Giovenale; E. Di Palma; G. Di Pirro; A. Dodaro; A. Doria; U. Dosselli; A. Drago; R. Escribano; A. Esposito; R. Faccini; A. Ferrari; M. Ferrario; A. Filabozzi; D. Filippetto; F. Fiori; O. Frasciello; L. Fulgentini; G. P. Gallerano; A. Gallo; M. Gambaccini; C. Gatti; G. Gatti; P. Gauzzi; A. Ghigo; G. Ghiringhelli; L. Giannessi; G. Giardina; C. Giannini; F. Giorgianni; E. Giovenale; L. Gizzi; C. Guaraldo; C. Guazzoni; R. Gunnella; K. Hatada; S. Ivashyn; F. Jegerlehner; P. O. Keeffe; W. Kluge; A. Kupsc; M. Iannone; L. Labate; P. Levi Sandri; V. Lombardi; P. Londrillo; S. Loreti; M. Losacco; S. Lupi; A. Macchi; S. Magazu'; G. Mandaglio; A. Marcelli; G. Margutti; C. Mariani; P. Mariani; G. Marzo; C. Masciovecchio; P. Masjuan; M. Mattioli; G. Mazzitelli; N. P. Merenkov; P. Michelato; F. Migliardo; M. Migliorati; C. Milardi; E. Milotti; S. Milton; V. Minicozzi; S. Mobilio; S. Morante; D. Moricciani; A. Mostacci; V. Muccifora; F. Murtas; P. Musumeci; F. Nguyen; A. Orecchini; G. Organtini; P. L. Ottaviani; E. Pace; M. Paci; C. Pagani; S. Pagnutti; V. Palmieri; L. Palumbo; G. C. Panaccione; C. F. Papadopoulos; M. Papi; M. Passera; L. Pasquini; M. Pedio; A. Perrone; A. Petralia; C. Petrillo; V. Petrillo; M. Pillon; P. Pierini; A. Pietropaolo; A. D. Polosa; R. Pompili; J. Portoles; T. Prosperi; C. Quaresima; L. Quintieri; J. V. Rau; M. Reconditi; A. Ricci; R. Ricci; G. Ricciardi; E. Ripiccini; S. Romeo; C. Ronsivalle; N. Rosato; J. B. Rosenzweig; G. Rossi; A. A. Rossi; A. R. Rossi; F. Rossi; D. Russo; A. Sabatucci; E. Sabia; F. Sacchetti; S. Salducco; F. Sannibale; G. Sarri; T. Scopigno; L. Serafini; D. Sertore; O. Shekhovtsova; I. Spassovsky; T. Spadaro; B. Spataro; F. Spinozzi; A. Stecchi; F. Stellato; V. Surrenti; A. Tenore; A. Torre; L. Trentadue; S. Turchini; C. Vaccarezza; A. Vacchi; P. Valente; G. Venanzoni; S. Vescovi; F. Villa; G. Zanotti; N. Zema; M. Zobov

2013-07-30T23:59:59.000Z

336

Accelerator and electrodynamics capability review  

Science Conference Proceedings (OSTI)

Los Alamos National Laboratory (LANL) uses capability reviews to assess the science, technology and engineering (STE) quality and institutional integration and to advise Laboratory Management on the current and future health of the STE. Capability reviews address the STE integration that LANL uses to meet mission requirements. The Capability Review Committees serve a dual role of providing assessment of the Laboratory's technical contributions and integration towards its missions and providing advice to Laboratory Management. The assessments and advice are documented in reports prepared by the Capability Review Committees that are delivered to the Director and to the Principal Associate Director for Science, Technology and Engineering (PADSTE). Laboratory Management will use this report for STE assessment and planning. LANL has defined fifteen STE capabilities. Electrodynamics and Accelerators is one of the seven STE capabilities that LANL Management (Director, PADSTE, technical Associate Directors) has identified for review in Fiscal Year (FY) 2010. Accelerators and electrodynamics at LANL comprise a blend of large-scale facilities and innovative small-scale research with a growing focus on national security applications. This review is organized into five topical areas: (1) Free Electron Lasers; (2) Linear Accelerator Science and Technology; (3) Advanced Electromagnetics; (4) Next Generation Accelerator Concepts; and (5) National Security Accelerator Applications. The focus is on innovative technology with an emphasis on applications relevant to Laboratory mission. The role of Laboratory Directed Research and Development (LDRD) in support of accelerators/electrodynamics will be discussed. The review provides an opportunity for interaction with early career staff. Program sponsors and customers will provide their input on the value of the accelerator and electrodynamics capability to the Laboratory mission.

Jones, Kevin W [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

337

Design of the NSLS-II Linac Front End Test Stand  

SciTech Connect

The NSLS-II operational parameters place very stringent requirements on the injection system. Among these are the charge per bunch train at low emittance that is required from the linac along with the uniformity of the charge per bunch along the train. The NSLS-II linac is a 200 MeV linac produced by Research Instruments Gmbh. Part of the strategy for understanding to operation of the injectors is to test the front end of the linac prior to its installation in the facility. The linac front end consists of a 100 kV electron gun, 500 MHz subharmonic prebuncher, focusing solenoids and a suite of diagnostics. The diagnostics in the front end need to be supplemented with an additional suite of diagnostics to fully characterize the beam. In this paper we discuss the design of a test stand to measure the various properties of the beam generated from this section. In particular, the test stand will measure the charge, transverse emittance, energy, energy spread, and bunching performance of the linac front end under all operating conditions of the front end.

Fliller III, R.; Johanson, M.; Lucas, M.; Rose, J.; Shaftan, T.

2011-03-28T23:59:59.000Z

338

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

AAI Home AAI Home Welcome Accelerators at Argonne Mission Organization History Document Collection Conferences & Workshops Beams and Applications Seminar Argonne-Fermilab Collaboration Lee Teng Scholarship Program Useful Links Argonne Accelerator Institute In 2006, Argonne Laboratory Director Robert Rosner formed the AAI as a focal point for accelerator initiatives. The institute works to utilize Argonne's extensive accelerator resources, to enhance existing facilities, to determine the future of accelerator development and construction, and to oversee a dynamic and acclaimed accelerator physics portfolio. More Information for: Members * Students Industrial Collaborators - Working with Argonne Link to: Accelerators for America's Future Upcoming Events and News 4th International Particle Accelerator Conference (IPAC'13)

339

Science Accelerator Widget  

Office of Scientific and Technical Information (OSTI)

Science Accelerator Widget You can now explore multiple Science Accelerator features through the new tabbed widget. Download this tool via the 'Get Widget Options' link or by...

340

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerators at Argonne Argonne has a long and continuing history of participation in accelerator based, and user oriented facilities. The Zero-Gradient Synchrotron, which began...

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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341

Permanent magnet focused X-band photoinjector  

DOE Patents (OSTI)

A compact high energy photoelectron injector integrates the photocathode directly into a multicell linear accelerator with no drift space between the injection and the linac. High electron beam brightness is achieved by accelerating a tightly focused electron beam in an integrated, multi-cell, X-band rf linear accelerator (linac). The photoelectron linac employs a Plane-Wave-Transformer (PWT) design which provides strong cell-to-cell coupling, easing manufacturing tolerances and costs.

Yu, David U. L. (Rancho Palos Verdes, CA); Rosenzweig, James (Los Angeles, CA)

2002-09-10T23:59:59.000Z

342

ACCELERATING POLARIZED PROTONS TO HIGH ENERGY.  

SciTech Connect

The Relativistic Heavy Ion Collider (RHIC) is designed to provide collisions of high energy polarized protons for the quest of understanding the proton spin structure. Polarized proton collisions at a beam energy of 100 GeV have been achieved in RHIC since 2001. Recently, polarized proton beam was accelerated to 250 GeV in RHIC for the first time. Unlike accelerating unpolarized protons, the challenge for achieving high energy polarized protons is to fight the various mechanisms in an accelerator that can lead to partial or total polarization loss due to the interaction of the spin vector with the magnetic fields. We report on the progress of the RHIC polarized proton program. We also present the strategies of how to preserve the polarization through the entire acceleration chain, i.e. a 200 MeV linear accelerator, the Booster, the AGS and RHIC.

BAI, M.; AHRENS, L.; ALEKSEEV, I.G.; ALESSI, J.; BEEBE-WANG, J.; BLASKIEWICZ, M.; BRAVAR, A.; BRENNAN, J.M.; BRUNO, D.; BUNCE, G.; ET AL.

2006-10-02T23:59:59.000Z

343

Unfolding linac photon spectra and incident electron energies from experimental transmission data, with direct independent validation  

SciTech Connect

Purpose: In a recent computational study, an improved physics-based approach was proposed for unfolding linac photon spectra and incident electron energies from transmission data. In this approach, energy differentiation is improved by simultaneously using transmission data for multiple attenuators and detectors, and the unfolding robustness is improved by using a four-parameter functional form to describe the photon spectrum. The purpose of the current study is to validate this approach experimentally, and to demonstrate its application on a typical clinical linac. Methods: The validation makes use of the recent transmission measurements performed on the Vickers research linac of National Research Council Canada. For this linac, the photon spectra were previously measured using a NaI detector, and the incident electron parameters are independently known. The transmission data are for eight beams in the range 10-30 MV using thick Be, Al and Pb bremsstrahlung targets. To demonstrate the approach on a typical clinical linac, new measurements are performed on an Elekta Precise linac for 6, 10 and 25 MV beams. The different experimental setups are modeled using EGSnrc, with the newly added photonuclear attenuation included. Results: For the validation on the research linac, the 95% confidence bounds of the unfolded spectra fall within the noise of the NaI data. The unfolded spectra agree with the EGSnrc spectra (calculated using independently known electron parameters) with RMS energy fluence deviations of 4.5%. The accuracy of unfolding the incident electron energy is shown to be {approx}3%. A transmission cutoff of only 10% is suitable for accurate unfolding, provided that the other components of the proposed approach are implemented. For the demonstration on a clinical linac, the unfolded incident electron energies and their 68% confidence bounds for the 6, 10 and 25 MV beams are 6.1 {+-} 0.1, 9.3 {+-} 0.1, and 19.3 {+-} 0.2 MeV, respectively. The unfolded spectra for the clinical linac agree with the EGSnrc spectra (calculated using the unfolded electron energies) with RMS energy fluence deviations of 3.7%. The corresponding measured and EGSnrc-calculated transmission data agree within 1.5%, where the typical transmission measurement uncertainty on the clinical linac is 0.4% (not including the uncertainties on the incident electron parameters). Conclusions: The approach proposed in an earlier study for unfolding photon spectra and incident electron energies from transmission data is accurate and practical for clinical use.

Ali, E. S. M.; McEwen, M. R.; Rogers, D. W. O. [Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada); Ionizing Radiation Standards, Institute for National Measurement Standards, National Research Council, M-35 Montreal Road, Ottawa, Ontario K1A 0R5 (Canada); Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)

2012-11-15T23:59:59.000Z

344

Ultra-High Gradient Compact S-Band Linac for Laboratory and Industrial Applications  

SciTech Connect

There is growing demand from the industrial and research communities for high gradient, compact RF accelerating structures. The commonly used S-band SLAC-type structure has an operating gradient of only about 20 MV/m; while much higher operating gradients (up to 70 MV/m) have been recently achieved in X-band, as a consequence of the substantial efforts by the Next Linear Collider (NLC) collaboration to push the performance envelope of RF structures towards higher accelerating gradients. Currently however, high power X-band RF sources are not readily available for industrial applications. Therefore, RadiaBeam Technologies is developing a short, standing wave S-band structure which uses frequency scaled NLC design concepts to achieve up to a 50 MV/m operating gradient at 2856 MHz. The design and prototype commissioning plans are presented.

Faillace, Luigi; /RadiaBeam Tech.; Agustsson, Ronald; /RadiaBeam Tech.; Frigola, Pedro; /RadiaBeam Tech.; Murokh, Alex; /RadiaBeam Tech.; Dolgashev, Valery; /SLAC; Rosenzweig, James; /UCLA

2012-07-03T23:59:59.000Z

345

Preliminary Analysis on Linac Oscillation Data LI05-19 and Wake Field Energy Loss in FACET Commissioning 2012  

SciTech Connect

In this note, preliminary analysis on linac ocsillation data in FACET linac LI05-09 plus LI11-19 is presented. Several quadrupoles are identified to possibly have different strength, compared with their designed strength in the MAD optics model. The beam energy loss due to longitudinal wake fields in the S-band linac is also analytically calculated, also by LITRACK numerical simulations.

Sun, Yipeng; /SLAC

2012-07-23T23:59:59.000Z

346

Post-accelerator issues at the IsoSpin Laboratory  

SciTech Connect

The workshop on ``Post-Accelerator Issues at the Isospin Laboratory`` was held at the Lawrence Berkeley Laboratory from October 27--29, 1993. It was sponsored by the Center for Beam Physics in the Accelerator and Fusion Research Division and the ISL Studies Group in the Nuclear Science Division. About forty scientists from around the world participated vigorously in this two and a half day workshop, (c.f. Agenda, Appendix D). Following various invited review talks from leading practitioners in the field on the first day, the workshop focussed around two working groups: (1) the Ion Source and Separators working group and (2) the Radio Frequency Quadrupoles and Linacs working group. The workshop closed with the two working groups summarizing and outlining the tasks for the future. This report documents the proceedings of the workshop and includes the invited review talks, the two summary talks from the working groups and individual contributions from the participants. It is a complete assemblage of state-of-the-art thinking on ion sources, low-{beta}, low(q/A) accelerating structures, e.g. linacs and RFQS, isobar separators, phase-space matching, cyclotrons, etc., as relevant to radioactive beam facilities and the IsoSpin Laboratory. We regret to say that while the fascinating topic of superconducting low-velocity accelerator structure was covered by Dr. K. Shepard during the workshop, we can only reproduce the copies of the transparencies of his talk in the Appendix, since no written manuscript was available at the time of publication of this report. The individual report have been catologed separately elsewhere.

Chattopadhyay, S.; Nitschke, J.M. [eds.

1994-05-01T23:59:59.000Z

347

Status of the plasma generator of the superconducting proton linac  

SciTech Connect

In the framework of the superconducting proton linac (SPL) study at CERN, a new non-cesiated H{sup -} plasma generator driven by an external 2 MHz RF antenna has been developed and successfully operated at repetition rates of 50 Hz, pulse lengths of up to 3 ms, and average RF powers of up to 3 kW. The coupling efficiency of RF power into the plasma was determined by the cooling water temperatures and the analysis of the RF forward and reflected power and the antenna current and amounts to 50%-60%. The plasma resistance increases between 10 kW and 40 kW RF power from about 0.45 {Omega} to 0.65 {Omega}. Measurements of RF power dissipated in the ferrites and the magnets on a test bench show a 5-fold decrease of the power losses for the magnets when they are contained in a Cu box, thus validating the strategy of shielding the magnets with a high electrical conductivity material. An air cooling system was installed in the SPL plasma generator to control the temperatures of the ferrites despite hysteresis losses of several Watts.

Kronberger, M.; Lettry, J.; Paoluzzi, M.; Pereira, H.; Arias, J. Sanchez; Schmitzer, C.; Scrivens, R. [European Organisation for Nuclear Research, CERN, 1211 Geneva 23 (Switzerland); Faircloth, D. [STFC, Rutherford Appleton Laboratory, Chilton, Oxon OX11 0QX (United Kingdom)

2012-02-15T23:59:59.000Z

348

Beam-based Feedback for the Linac Coherent Light Source  

SciTech Connect

Beam-based feedback control loops are required by the Linac Coherent Light Source (LCLS) program in order to provide fast, single-pulse stabilization of beam parameters. Eight transverse feedback loops, a 6 x 6 longitudinal feedback loop, and a loop to maintain the electron bunch charge were successfully prototyped in MATLAB for the LCLS, and have been maintaining stability of the LCLS electron beam at beam rates up to 30Hz. In the final commissioning phase of LCLS the beam will be operating at up to 120Hz. In order to run the feedback loops at beam rate, the feedback loops will be implemented in EPICS IOCs with a dedicated ethernet multi-cast network. This paper will discuss the design of the beam-based Fast Feedback System for LCLS. Topics include MATLAB feedback prototyping, algorithm for 120Hz feedback, network design for fast data transport, actuator and sensor design for single-pulse control and sensor readback, and feedback configuration and runtime control.

Fairley, D.; Allison, S.; Chevtsov, S.; Chu, P.; Decker, F.J.; Emma, P.; Frisch, J.; Himel, T.; Kim, K.; Krejcik, P.; Loos, H.; Lahey, T.; Natampalli, P.; Peng, S.; Rogind, D.; Shoaee, H.; Straumann, T.; Williams, E.; White, G.; Wu, J.; Zelazney, M.; /SLAC

2010-02-11T23:59:59.000Z

349

Identifying Longitudinal Jitter Sources in the LCLS Linac  

Science Conference Proceedings (OSTI)

The Linac Coherent Light Source (LCLS) at SLAC is an x-ray Free Electron Laser (FEL) with wavelengths of 0.15 nm to 1.5 nm. The electron beam stability is important for good lasing. While the transverse jitter of the beam is about 10-20% of the rms beam sizes, the jitter in the longitudinal phase space is a multiple of the energy spread and bunch length. At the lower energy of 4.3 GeV (corresponding to the longest wavelength of 1.5 nm) the relative energy jitter can be 0.125%, while the rms energy spread is with 0.025% five times smaller. An even bigger ratio exists for the arrival time jitter of 50 fs and the bunch duration of about 5 fs (rms) in the low charge (20 pC) operating mode. Although the impact to the experiments is reduced by providing pulse-by-pulse data of the measured energy and arrival time, it would be nice to understand and mitigate the root causes of this jitter. The thyratron of the high power supply of the RF klystrons is one of the main contributors. Another suspect is the multi-pacting in the RF loads. Phase measurements down to 0.01 degree (equals 10 fs) along the RF pulse were achieved, giving hints to the impact of the different sources.

Decker, Franz-Josef; /SLAC; Akre, Ron; /SLAC; Brachmann, Axel; /SLAC; Craft, Jim; /SLAC; Ding, Yuantao; /SLAC; Dowell, David; /SLAC; Emma, Paul; /SLAC; Frisch, Josef; /SLAC; Huang, Zhirong; /SLAC; Iverson, Richard; /SLAC; Krasnykh, Anatoly; /SLAC; Loos, Henrik; /SLAC; Nuhn, Heinz-Dieter; /SLAC; Ratner, Daniel; /SLAC; Smith, Tonee; /SLAC; Turner, James; /SLAC; Welch, James; /SLAC; White, William; /SLAC; Wu, Juhao; /SLAC

2012-07-06T23:59:59.000Z

350

Linear Collider Collaboration Tech Notes LCC-0104  

NLE Websites -- All DOE Office Websites (Extended Search)

4 4 October 2002 Beamstrahlung Photon Load on the TESLA Extraction Septum Blade Andrei Seryi Stanford Linear Accelerator Center Stanford, CA 94309, USA Abstract: This note describes work performed in the framework of the International Linear Collider Technical Review Committee [1] to estimate the power load on the TESLA extraction septum blade due to beamstrahlung photons. It is shown, that under realistic conditions the photon load can be several orders of magnitude higher than what was estimated in the TESLA TDR [2] for the ideal Gaussian beams, potentially representing a serious limitation of the current design. Beamstrahlung Photon Load on the TESLA Extraction Septum Blade ANDREI SERYI STANFORD LINEAR

351

TESTING METGLAS FOR USE IN DARHT ACCELERATOR CELLS  

SciTech Connect

The Dual Axis Radiographic Hydrotest Facility [DARHT] at Los Alamos will use two induction linacs to produce high-energy electron beams. The electron beams will be used to generate x-rays from bremsstrahlung targets. The x-rays will be used to produce radiographs. The first accelerator is operational now, producing a 60-nanosecond electron beam. The second accelerator is under construction. It will produce a 2-microsecond electron beam. The 78 induction cells of the second axis accelerator require a total Metglas capacity of approximately 40 volt seconds of flux. Four Metglas cores are used in each of the 5-foot diameter accelerator cells. Each Metglas core weighs approximately 3000 pounds. This paper presents the measurement techniques and results of the Metglas tests. Routine automated analysis and archival of the pulse data provided hysteresis curves, energy loss curves and total flux swing in the operating regime. Results of the tests were used to help the manufacturer improve quality control and increase the average flux swing of the cores. Results of the tests were used to match Metglas cores and to assemble accelerator cells with equal volt-second ratings.

E.A. ROSE; D.A. DALMAS; J.N. DOWNING; R.D. TEMPLE

2001-06-01T23:59:59.000Z

352

NIST MIRF - Accelerator Radiation Physics  

Science Conference Proceedings (OSTI)

Accelerator Radiation Physics. Medium-energy accelerators are under investigation for production of channeling radiation ...

353

Fermilab | Illinois Accelerator Research Center | Illinois Accelerator  

NLE Websites -- All DOE Office Websites (Extended Search)

photo: IARC photo: IARC As envisioned, the Illinois Accelerator Research Center will provide approximately 83,000 square feet of technical, office and classroom space for scientists and industrial partners. The Illinois Accelerator Research Center (IARC) is a new accelerator research facility being built at Fermi National Accelerator Laboratory. At the Illinois Accelerator Research Center, scientists and engineers from Fermilab, Argonne and Illinois universities will work side by side with industrial partners to research and develop breakthroughs in accelerator science and translate them into applications for the nation's health, wealth and security. Located on the Fermilab campus this 83,000 square foot, state-of-the-art facility will house offices, technical and educational space to study

354

Thomas Jefferson National Accelerator Facility  

Science Conference Proceedings (OSTI)

The Thomas Jefferson National Accelerator Facility (Jefferson Lab) in Newport News, Virginia, USA, is one of ten national laboratories under the aegis of the Office of Science of the U.S. Department of Energy (DOE). It is managed and operated by Jefferson Science Associates, LLC. The primary facility at Jefferson Lab is the Continuous Electron Beam Accelerator Facility (CEBAF) as shown in an aerial photograph in Figure 1. Jefferson Lab was created in 1984 as CEBAF and started operations for physics in 1995. The accelerator uses superconducting radio-frequency (srf) techniques to generate high-quality beams of electrons with high-intensity, well-controlled polarization. The technology has enabled ancillary facilities to be created. The CEBAF facility is used by an international user community of more than 1200 physicists for a program of exploration and study of nuclear, hadronic matter, the strong interaction and quantum chromodynamics. Additionally, the exceptional quality of the beams facilitates studies of the fundamental symmetries of nature, which complement those of atomic physics on the one hand and of high-energy particle physics on the other. The facility is in the midst of a project to double the energy of the facility and to enhance and expand its experimental facilities. Studies are also pursued with a Free-Electron Laser produced by an energy-recovering linear accelerator.

Joseph Grames, Douglas Higinbotham, Hugh Montgomery

2010-09-01T23:59:59.000Z

355

Petawatt pulsed-power accelerator  

DOE Patents (OSTI)

A petawatt pulsed-power accelerator can be driven by various types of electrical-pulse generators, including conventional Marx generators and linear-transformer drivers. The pulsed-power accelerator can be configured to drive an electrical load from one- or two-sides. Various types of loads can be driven; for example, the accelerator can be used to drive a high-current z-pinch load. When driven by slow-pulse generators (e.g., conventional Marx generators), the accelerator comprises an oil section comprising at least one pulse-generator level having a plurality of pulse generators; a water section comprising a pulse-forming circuit for each pulse generator and a level of monolithic triplate radial-transmission-line impedance transformers, that have variable impedance profiles, for each pulse-generator level; and a vacuum section comprising triplate magnetically insulated transmission lines that feed an electrical load. When driven by LTD generators or other fast-pulse generators, the need for the pulse-forming circuits in the water section can be eliminated.

Stygar, William A. (Albuquerque, NM); Cuneo, Michael E. (Albuquerque, NM); Headley, Daniel I. (Albuquerque, NM); Ives, Harry C. (Albuquerque, NM); Ives, legal representative; Berry Cottrell (Albuquerque, NM); Leeper, Ramon J. (Albuquerque, NM); Mazarakis, Michael G. (Albuquerque, NM); Olson, Craig L. (Albuquerque, NM); Porter, John L. (Sandia Park, NM); Wagoner; Tim C. (Albuquerque, NM)

2010-03-16T23:59:59.000Z

356

Design considerations for a laser-plasma linear collider  

SciTech Connect

Design considerations for a next-generation electron-positron linear collider based on laser-plasma-accelerators are discussed. Several of the advantages and challenges of laser-plasma based accelerator technology are addressed. An example of the parameters for a 1 TeV laser-plasma based collider is presented.

Schroeder, C. B.; Esarey, E.; Geddes, C. G. R.; Toth, Cs.; Leemans, W. P.

2008-08-01T23:59:59.000Z

357

SLAC National Accelerator Laboratory - SLAC National Accelerator...  

NLE Websites -- All DOE Office Websites (Extended Search)

Security Notice and Terms of Use Updated January 3, 2005 PRIVACY NOTICE Welcome to the SLAC National Accelerator Laboratory website. We collect no personal information about you...

358

High-power proton linac for APT facility  

Science Conference Proceedings (OSTI)

In one of two options being considered for a new source of tritium, the US Department of Energy (DOE) is planning an Accelerator Production of Tritium (APT) plant that would be built at its Savannah River Site in South Carolina. The project Conceptual Design Report was issued in April, 1997, and formal design of the plant technical and conventional systems has now begun. A program of engineering development and demonstration (ED and D) has been underway since 1995 to support the plant design and subsequent construction; the accelerator portion of this program is summarized.

Lawrence, G.P.

1998-12-01T23:59:59.000Z

359

X-ray-optical cross-correlator for gas-phase experiments at the Linac Coherent Light Source free-electron laser  

Science Conference Proceedings (OSTI)

X-ray-optical pump-probe experiments at the Linac Coherent Light Source (LCLS) have so far been limited to a time resolution of 280 fs fwhm due to timing jitter between the accelerator-based free-electron laser (FEL) and optical lasers. We have implemented a single-shot cross-correlator for femtosecond x-ray and infrared pulses. A reference experiment relying only on the pulse arrival time information from the cross-correlator shows a time resolution better than 50 fs fwhm (22 fs rms) and also yields a direct measurement of the maximal x-ray pulse length. The improved time resolution enables ultrafast pump-probe experiments with x-ray pulses from LCLS and other FEL sources.

Schorb, S.; Cryan, J. P.; Glownia, J. M.; Bionta, M. R.; Coffee, R. N.; Swiggers, M.; Carron, S.; Castagna, J.-C.; Bozek, J. D.; Messerschmidt, M.; Schlotter, W. F.; Bostedt, C. [Linac Coherent Light Source, SLAC National Accelerator Laboratory, P.O. Box 20450, Stanford, California 94309 (United States); Gorkhover, T. [Institut fuer Optik und Atomare Physik, Technische Universitaet Berlin, Hardenbergstr. 36, 10623 Berlin (Germany); Erk, B.; Boll, R.; Schmidt, C.; Rudenko, A. [Max-Planck Advanced-Study-Group at CFEL, Notkestr. 85, 22607 Hamburg (Germany); Max-Planck-Institut f. Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Rolles, D. [Max-Planck Advanced-Study-Group at CFEL, Notkestr. 85, 22607 Hamburg (Germany); Max-Planck-Institut f. med. Forschung, Jahnstr. 29, 69120 Heidelberg (Germany); Rouzee, A. [Max-Born-Institut, Max-Born-Str. 2, 12489 Berlin (Germany)

2012-03-19T23:59:59.000Z

360

Proceedings of the first international workshop on accelerator alignment  

Science Conference Proceedings (OSTI)

This report contains papers on the following accelerator topics: current alignment topics; toolboxes: instrumentation, software, and methods; fiducialization of conventional magnets; fiducialization of superconducting magnets; and next generation linear colliders.

Not Available

1990-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Laser-PlasmaWakefield Acceleration with Higher Order Laser Modes  

E-Print Network (OSTI)

Design considerations for a laser-plasma linear collider,"E.Esarey, and W.P.Leemans, "Free-electron laser driven bythe LBNL laser-plasma accelerator," in Proc. Adv. Acc. Con.

Geddes, C.G.R.

2011-01-01T23:59:59.000Z

362

Linear Thermite Charge  

The Linear Thermite Charge (LTC) is designed to rapidly cut through concrete and steel structural components by using extremely high temperature thermite reactions jetted through a linear nozzle. 

363

DOE - Office of Legacy Management -- Stanford Linear Accelerator...  

Office of Legacy Management (LM)

Center was established in 1962 as a research facility for high energy particle physics. The Environmental Management mission at this site is to clean up soils and...

364

STANFORD LINEAR ACCELERATOR CENTER Winter 1999, Vol. 29, No. 3  

E-Print Network (OSTI)

Energy. It has been my pleasure to collaborate with Hans D. Gouger, Kevan D. Weaver and J. Steven Herring

California at Santa Cruz, University of

365

2010 Annual Planning Summary for Stanford Linear Accelerator...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Annual Planning Summary for National Nuclear Security Administration Service Center (NNSA-SC) 2010 Annual Planning Summary for Nevada Site Office Energy.gov Careers & Internships...

366

STANFORD LINEAR ACCELERATOR CENTER FY 2004 FY2010  

E-Print Network (OSTI)

of natural gas, compressed air, cooling-tower water, chilled water and hot water systems. These systems LF 3 sensors and PLC controllers at least two (2) out of four (4) cooling towers: 101, 1201, 1202 and 1701 therefore allowing optimizing the blow-down cycles. 27. Implement Title II design of campus cooling tower CT

Wechsler, Risa H.

367

Some aspects of superconducting accelerator design  

SciTech Connect

The performance of an accelerator can be characterized by the efficiency with which electrical energy, the minimumm energy needed to generate a given beam voltage. The current accelerator improvement program at SLAC aims at raising the beam voltage to 50 GV which will use 240 klystrons each capable of producing a pulse 5 ..mu..s in length at a peak power of 36 MW. The Linear Collider requires 50 MW klystrons to achieve 60 GV which will raise the concomittant power consumption to 32.3 MW. We show that with superconducting elements we can increase the rf and ac conversion efficiencies and achieve the necessary 50 GV using only 1/3 of the present power requirements, provided that we exclude CW operation. We will further demonstrate that this increase in efficiency is crucial and highly significant in the design of a proposed 1000 GV linear accelerator.

Farkas, Z.D.; St. Lorant, S.J.

1982-11-01T23:59:59.000Z

368

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Research and Development Research and Development Click to download a PDF version of this document. PDF Focus Research Areas Fundamental Accelerator Physics: Theory Importance Accelerator physics research is normally associated with specific accelerator projects. As a scientific discipline, however, it is useful to study fundamental accelerator phenomena decoupled, as much as possible, from specific project aspects. Pursuit of fundamental accelerator physics in this sense has contributed significantly to the advance of the accelerator physics knowledgebase during the last several decades, clarifying the limitations and suggesting ways to overcome those limitations. Such basic research tends to be discouraged in a project-driven environment. For sustained and significant progress in

369

Experimental Plans to Explore Dielectric Wakefield Acceleration in the THZ Regime  

SciTech Connect

Dielectric wakefield accelerators have shown great promise toward high-gradient acceleration. We investigate the performances of a possible experiment under consideration at the FLASH facility in DESY to explore wakefield acceleration with an enhanced transformer ratio. The experiment capitalizes on a unique pulse shaping capability recently demonstrated at this facility. In addition, the facility incorporates a superconducting linear accelerator that could generate bunch trains with closely spaced bunches thereby opening the exploration of potential dynamical effects in dielectric wakefield accelerators.

Lemery, F.; Mihalcea, D.; /Northern Illinois U.; Piot, P.; /Fermilab; Behrens, C.; Elsen, E.; Flottmann, K.; Gerth, C.; Kube, G.; Schmidt, B.; /DESY; Osterhoff, J.; /Hamburg U., Inst. Theor. Phys. II; Stoltz, P.

2011-09-07T23:59:59.000Z

370

High-energy lattice for first-beam operation of the SRF test accelerator at NML  

Science Conference Proceedings (OSTI)

The Superconducting Radio Frequency Test Accelerator, a linear electron accelerator currently in construction at Fermilab's New Muon Laboratory, will eventually reach energies of {approx} 900 MeV using four ILC-type superconducting accelerating cryomodules. The accelerator's construction is staged according to cryomodules availability. The first phase that will support first beam operation incorporates one cryomodule. In this Note, we summarize a possible design for the first-beam accelerator configuration.

Prokop, C.; /NICADD, DeKalb; Piot, P.; /NICADD, DeKalb /Fermilab; Church, M.; /Fermilab

2011-09-01T23:59:59.000Z

371

Optical Design of a Broadband Infrared Spectrometer for Bunch Length Measurement at the Linac Coherent Light Source  

SciTech Connect

The electron pulses generated by the Linac Coherent Light Source at the SLAC National Accelerator Laboratory occur on the order of tens of femtoseconds and cannot be directly measured by conventional means. The length of the pulses can instead be reconstructed by measuring the spectrum of optical transition radiation emitted by the electrons as they move toward a conducting foil. Because the emitted radiation occurs in the mid-infrared from 0.6 to 30 microns a novel optical layout is required. Using a helium-neon laser with wavelength 633 nm, a series of gold-coated off-axis parabolic mirrors were positioned to direct a beam through a zinc selenide prism and to a focus at a CCD camera for imaging. Constructing this layout revealed a number of novel techniques for reducing the aberrations introduced into the system by the off-axis parabolic mirrors. The beam had a recorded radius of less than a millimeter at its final focus on the CCD imager. This preliminary setup serves as a model for the spectrometer that will ultimately measure the LCLS electron pulse duration.

Williams, Kiel; /SLAC

2012-09-07T23:59:59.000Z

372

H-mode Accelerating Structures with PMQ Focusing for Low-Beta Beams  

SciTech Connect

We report on results of the project developing high-efficiency normal-conducting RF accelerating structures based on inter-digital H-mode (IH) cavities and the transverse beam focusing with permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of IH-PMQ structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. The H-PMQ accelerating structures following a short RFQ can be used both in the front end of ion linacs or in stand-alone applications. Results of the combined 3-D modeling -- electromagnetic computations, beam-dynamics simulations with high currents, and thermal-stress analysis -- for a full IH-PMQ accelerator tank are presented. The accelerating field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of EM and beamdynamics modeling. Multi-particle simulations withParmela and CST Particle Studio have been used to confirm the design. Measurement results of a cold model of the IH-PMQ tank are presented.

Kurennoy, Sergey S. [Los Alamos National Laboratory; O'Hara, James F. [Los Alamos National Laboratory; Olivas, Eric R. [Los Alamos National Laboratory; Rybarcyk, Lawrence J. [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

373

Plasma beat-wave accelerator  

Science Conference Proceedings (OSTI)

We perform an analytic study of some quantities relevant to the plasma beat-wave accelerator (PBWA) concept. We obtain analytic expressions for the plasma frequency, longitudinal electron velocity, plasma density and longitudinal plasma electric field of a nonlinear longitudinal electron plasma oscillation with amplitude less than the wave-breaking limit and phase velocity approaching the speed of light. We also estimate the luminosity of a single-pass e/sup +/e/sup -/ linear PBWA collider assuming the energy and collision beamstrahlung are fixed parameters.

Noble, R.J.

1983-06-01T23:59:59.000Z

374

Wakefields in photonic accelerator structures  

SciTech Connect

Control and manipulation of properties - such as vacuum modal confinement, spatial harmonic content, phase velocity, and group velocity - are reasons why an all-dielectric beam-driven accelerator would be expected to benefit by borrowing from the field of optical bandgap photonics. We outline the general conditions for coherent Cerenkov radiation in a photonic crystal, illustrated by three examples: two Bragg mirrors separated by a vacuum gap, a woodpile with a linear waveguide channel, and a stack of photonic slabs having a planar waveguide channel.

Naranjo, B.; Andonian, G.; Arab, E.; Barber, S.; Fitzmorris, K.; Fukusawa, A.; Hoang, P.; Mahapatra, S.; O'Shea, B.; Valloni, A.; Williams, O.; Yang, C.; Rosenzweig, J. B. [UCLA Dept. of Physics and Astronomy, Los Angeles, CA 90095-1547 (United States)

2012-12-21T23:59:59.000Z

375

Radiative Effects on Particle Acceleration via Relativistic Electromagnetic Expansion  

E-Print Network (OSTI)

We study the radiation effect on the diamagnetic relativistic pulse accelerator (DPRA) in two-and-half-dimensional particle-in-cell (PIC) plasma simulation with magnetized electron-positron plasmas. Radiation damping force is self-consistently calculated for each particle, which reduces the acceleration force and converts particle energy to radiation. The emitted radiation is strongly linearly polarized and peaked within few degrees from the direction of Poynting flux due to the relativistic acceleration by the DPRA.

Noguchi, K; Nishimura, K; Noguchi, Koichi; Liang, Edison; Nishimura, Kazumi

2004-01-01T23:59:59.000Z

376

Electrostatic quadrupole focused particle accelerating assembly with laminar flow beam  

DOE Patents (OSTI)

A charged particle accelerating assembly provided with a predetermined ratio of parametric structural characteristics and with related operating voltages applied to each of its linearly spaced focusing and accelerating quadrupoles, thereby to maintain a particle beam traversing the electrostatic fields of the quadrupoles in the assembly in an essentially laminar flow through the assembly.

Maschke, A.W.

1984-04-16T23:59:59.000Z

377

Advanced beam-dynamics simulation tools for the RIA driver linac,Part I: Low energy beam transport and radiofrequency quadrupole  

Science Conference Proceedings (OSTI)

Advanced Beam-Dynamics Simulation Tools for the RIA Driver Linac; Low Energy Beam Transport and Radiofrequency Quadrupole.

Wangler, Thomas P.; Crandall, Kenneth R.; Garnett, Robert W.; Gorelov, Dmitry; Ostroumov, Petr; Qiang, Ji; Ryne, Robert; York, Richard

2003-08-26T23:59:59.000Z

378

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

GEM - GeV Electron Microtron (design report 1982) The GEM design report describes a novel six-sided CW microtron for accelerating electrons to 4 GeV. This accelerator design was...

379

High-Brightness Beams from a Light Source Injector The Advanced Photon Source Low-Energy Undulator Test Line Linac  

E-Print Network (OSTI)

The use of existing linacs, and in particular light source injectors, for free-electron laser (FEL) experiments is becoming more common due to the desire to test FELs at ever shorter wavelengths. The high-brightness, high-current beams required by high-gain FELs impose technical specifications that most existing linacs were not designed to meet. Moreover, the need for specialized diagnostics, especially shot-to-shot data acquisition, demands substantial modification and upgrade of conventional linacs. Improvements have been made to the Advanced Photon Source (APS) injector linac in order to produce and characterize high-brightness beams. Specifically, effort has been directed at generating beams suitable for use in the low-energy undulator test line (LEUTL) FEL in support of fourth-generation light source research. The enhancements to the linac technical and diagnostic capabilities that allowed for self-amplified spontaneous emission (SASE) operation of the FEL at 530 nm are described. Recent results, includi...

Travish, G; Borland, M; Hahne, M; Harkay, K C; Lewellen, J W; Lumpkin, Alex H; Milton, S V; Sereno, N S

2000-01-01T23:59:59.000Z

380

Accelerating Electric Vehicle Deployment | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Accelerating Electric Vehicle Deployment Accelerating Electric Vehicle Deployment Accelerating Electric Vehicle Deployment Accelerating Electric Vehicle Deployment More Documents &...

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Far field acceleration  

SciTech Connect

Far fields are propagating electromagnetic waves far from their source, boundary surfaces, and free charges. The general principles governing the acceleration of charged particles by far fields are reviewed. A survey of proposed field configurations is given. The two most important schemes, Inverse Cerenkov acceleration and Inverse free electron laser acceleration, are discussed in detail.

Fernow, R.C.

1995-07-01T23:59:59.000Z

382

Toward laser ablation Accelerator Mass Spectrometry of actinides  

Science Conference Proceedings (OSTI)

A project to measure neutron capture cross sections of a number of actinides in a reactor environment by Accelerator Mass Spectrometry (AMS) at the ATLAS facility of Argonne National Laboratory is underway. This project will require the precise and accurate measurement of produced actinide isotopes in many (>30) samples irradiated in the Advanced Test Reactor at Idaho National Laboratory with neutron fluxes having different energy distributions. The AMS technique at ATLAS is based on production of highlycharged positive ions in an electron cyclotron resonance (ECR) ion source followed by acceleration in the ATLAS linac and mass-to-charge (m/q) measurement at the focus of the Fragment Mass Analyzer. Laser ablation was selected as the method of feeding the actinide material into the ion source because we expect it will have higher efficiency and lower chamber contamination than either the oven or sputtering techniques, because of a much narrower angular distribution of emitted material. In addition, a new multi-sample holder/changer to allow quick change between samples and a computer-controlled routine allowing fast tuning of the accelerator for different beams, are being developed. An initial test run studying backgrounds, detector response, and accelerator scaling repeatability was conducted in December 2010. The project design, schedule, and results of the initial test run to study backgrounds are discussed.

R. C. Pardo; F. G. Kondev; S. Kondrashev; C. Nair; T. Palchan; R. Scott; D. Seweryniak; R. Vondrasek; M. Paul; P. Collon; C. Deibel; M. Salvatores; G. Palmiotti; J. Berg; J. Fonnesbeck; G. Imel

2013-01-01T23:59:59.000Z

383

What is an accelerator operator?  

NLE Websites -- All DOE Office Websites (Extended Search)

is an accelerator operator? First I'll explain the education one must have in order to be considered for an Accelerator Operator position. Jefferson Lab's typical Accelerator...

384

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

AAI Homepage Lee Teng Scholarship Program USPAS Argonne Department of Education Fermilab Education Office For Students Many scientific advances are made using accelerators. The world of High Energy Particle Physics has driven this field and continues to depend largely on accelerators. Increasingly advances in materials science, chemistry, biology and environmental science are being made at accelerators using x-ray and neutrons to probe matter. Accelerators have a number of commercial applications including isotope production for use in medicine, cancer treatment, processing semiconductor chips, and so on. Presently there are around 15,000 accelerators worldwide. Approximately 97% of these are used for commercial applications. However several hundred are in use

385

SLAC National Accelerator Laboratory - Director of Accelerator...  

NLE Websites -- All DOE Office Websites (Extended Search)

Committee on Appropriations asked the US Department of Energy (DOE) to submit a strategic plan for accelerator R&D by June 2012. The DOE asked me to lead a task force to...

386

Acceleration in astrophysics  

SciTech Connect

The origin of cosmic rays and applicable laboratory experiments are discussed. Some of the problems of shock acceleration for the production of cosmic rays are discussed in the context of astrophysical conditions. These are: The presumed unique explanation of the power law spectrum is shown instead to be a universal property of all lossy accelerators; the extraordinary isotropy of cosmic rays and the limited diffusion distances implied by supernova induced shock acceleration requires a more frequent and space-filling source than supernovae; the near perfect adiabaticity of strong hydromagnetic turbulence necessary for reflecting the accelerated particles each doubling in energy roughly 10{sup 5} to {sup 6} scatterings with negligible energy loss seems most unlikely; the evidence for acceleration due to quasi-parallel heliosphere shocks is weak. There is small evidence for the expected strong hydromagnetic turbulence, and instead, only a small number of particles accelerate after only a few shock traversals; the acceleration of electrons in the same collisionless shock that accelerates ions is difficult to reconcile with the theoretical picture of strong hydromagnetic turbulence that reflects the ions. The hydromagnetic turbulence will appear adiabatic to the electrons at their much higher Larmor frequency and so the electrons should not be scattered incoherently as they must be for acceleration. Therefore the electrons must be accelerated by a different mechanism. This is unsatisfactory, because wherever electrons are accelerated these sites, observed in radio emission, may accelerate ions more favorably. The acceleration is coherent provided the reconnection is coherent, in which case the total flux, as for example of collimated radio sources, predicts single charge accelerated energies much greater than observed.

Colgate, S.A.

1993-12-31T23:59:59.000Z

387

Heavy ion fusion accelerator research (HIFAR) half-year report: October 1, 1986-March 31, 1987  

Science Conference Proceedings (OSTI)

For this report we have collected the papers presented by the HIFAR group at the IEEE Particle Accelerator Conference held in Washington, DC, on March 16-19, 1987, which essentially coincides with the end of the reporting period. In addition, we report on research to determine the cause of the failures of Re-X insulator that are used as the high-voltage feed-through for the electrostatic quadrupoles on MBE-4. This report contains papers on the following topics: LBL multiple beam experiments, pulsers for the induction linac experiment (MBE-4), HIF insulator failure, experimental measurement of emittance growth in mismatched space-charge dominated beams, the effect of nonlinear forces on coherently oscillating space-charge dominated beams, space-charge effects in a bending magnet system, transverse combining of nonrelativistic beams in a multiple beam induction linac, comparison of electric and magnetic quadrupole focusing for the low energy end of an induction-linac-ICF driver. Eight individual papers have been indexed separately. (LSP)

Not Available

1987-04-01T23:59:59.000Z

388

Linear Collider Collaboration Tech Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

5 08//00 5 08//00 Study of Beam Energy Spectrum Measurement in the NLC Extraction Line August 2000 Yuri Nosochkov and Tor Raubenheimer Stanford Linear Accelerator Center Stanford, CA Abstract: The NLC extraction line optics includes a secondary focal point with a very small _- function and 2 cm dispersion which can be used for measurement of outgoing beam energy spread. In this study, we performed tracking simulations to transport the NLC disrupted beam from the Interaction Point (IP) to the extraction line secondary focus (the IP image), `measure' the transverse beam pro_le at the IP image and reconstruct the beam energy spectrum. The resultant distribution was compared with the original energy spectrum at the IP. Study of Beam Energy Spectrum Measurement

389

Linear Collider Collaboration Tech Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

2 03/12/99 2 03/12/99 PEP-II RF Cavity Revisited December 3, 1999 R. Rimmer, G. Koehler, D. Li, N. Hartmann, N. Folwell, J. Hodgson, B. McCandless Lawrence Berkeley National Laboratory Stanford Linear Accelerator Center Berkeley, CA, USA Stanford, CA, USA Abstract: This report describes the results of numerical simulations of the PEP-II RF cavity performed after the completion of the construction phase of the project and comparisons are made to previous calculations and measured results. These analyses were performed to evaluate new calculation techniques for the HOM distribution and RF surface heating that were not available at the time of the original design. These include the use of a high frequency electromagnetic element in ANSYS and the new Omega 3P code to study wall

390

Linear Collider Collaboration Tech Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

4, 10/03/00 4, 10/03/00 Luminosity for NLC Design Variations March 10, 1999 K.A. Thompson and T.O. Raubenheimer Stanford Linear Accelerator Center Stanford, CA, USA Abstract: In this note we give Guineapig simulation results for the luminosity and luminosity spectrum of three baseline NLC designs at 0.5~TeV and 1.0~TeV and compare the simulation results with analytic approximations. We examine the effects of varying several design parameters away from the NLC-B-500 and NLC-B-1000 designs, in order to study possible trade-offs of parameters that could ease tolerances, increase luminosity, or help to optimize machine operation for specific physics processes. Luminosity for NLC Design Variations K.A. Thompson and T.O.Raubenheimer INTRODUCTION In this note we give Guineapig [l] simulation results for the luminosity and

391

Linear Collider Collaboration Tech Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

Notes Notes LCC - 0038 29/04/00 CBP Tech Note - 234 Transverse Field Profile of the NLC Damping Rings Electromagnet Wiggler 29 April 2000 17 J. Corlett and S. Marks Lawrence Berkeley National Laboratory M. C. Ross Stanford Linear Accelerator Center Stanford, CA Abstract: The primary effort for damping ring wiggler studies has been to develop a credible radiation hard electromagnet wiggler conceptual design that meets NLC main electron and positron damping ring physics requirements [1]. Based upon an early assessment of requirements, a hybrid magnet similar to existing designs satisfies basic requirements. However, radiation damage is potentially a serious problem for the Nd-Fe-B permanent magnet material, and cost remains an issue for samarium cobalt magnets. Superconducting magnet designs have not been

392

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Mission Mission The mission of the Argonne Accelerator Institute is centered upon the following related goals: Locate next generation accelerator facilities in Northern Illinois Advance accelerator technology Oversee a selected, strategic, lab-wide, and acclaimed accelerator R&D portfolio In order to accomplish the above goals, the institute has established five objectives. These are coupled to programmatic objectives, and are dependent on each other, but they serve to identify important areas for the institute to focus its activities. Educate the "next generation" of accelerator physicists and engineers Work with area Universities to establish Joint Appointments and Adjunct Professorships Identify students Provide research opportunities at Argonne Work with the US Particle Accelerator School

393

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Welcome Welcome In 2006, Argonne laboratory director Robert Rosner formed the AAI as a focal point for accelerator initiatives. The institute works to utilize Argonne's extensive accelerator resources, to enhance existing facilities, to determine the future of accelerator development and construction, and to oversee a dynamic and acclaimed accelerator physics portfolio. I invite you to look around the content of this web site. Accelerators at Argonne describes our rich heritage in this field, particularly with respect to the development and support of user facilities. Initiatives describes the things we are hoping to do, and Research & Development discusses our research portfolio. If you are a graduate or undergraduate student wishing to pursue a career in accelerator science or technology, please see Educational

394

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

The Argonne Accelerator History Document Collection The Argonne Accelerator History Document Collection The Argonne Accelerator Institute (AAI) has established a special collection of archived documents which describe notable Argonne accelerator work of the past 50 years. A list of such Argonne Accelerator Projects is given below. Each project is described briefly, with links to archived documents in this collection. This collection includes important Argonne accelerator documents which may have become difficult to locate, as well as ones which have broad scope. In keeping with its historical purpose, this collection only covers work done 10 or more years ago. Many of the listed documents are available online. We hope to make more of them available online in the future. [For several of the projects, interesting additional online documents can be found by

395

accelerators for ATI  

NLE Websites -- All DOE Office Websites (Extended Search)

Building Accelerator Analogs Building Accelerator Analogs Some QuarkNet centers have built "accelerators." No, they are not real but can be used as analogs to real particle accelerators. The real learning comes, of course, when you plan and experiment on your own, but this may give you some starting points. Things to Think About What are your objectives? To make an analogy for particle accelerators? To use classical physics qualitatively? To use classical physics quantitatively? To measure forces, speed, etc.? _______________ Who is your target audience— in an Associate Teacher Institute or their students or both? What do the participants need to know before beginning? Jawbreaker Accelerator Pressurized gas shoots jawbreakers through PVC pipe into a fixed target (brick) or into each other. The original speeds and masses are measured as are those of the resulting particles.

396

A Los Alamos concept for accelerator transmutation of waste and energy production (ATW)  

SciTech Connect

This document contains the diagrams presented at the ATW (Accelerator Transmutation of Waste and Energy Production) External Review, December 10-12, 1990, held at Los Alamos National Laboratory. Included are the charge to the committee and the presentations for the committee`s review. Topics of the presentations included an overview of the concept, LINAC technology, near-term application -- high-level defense wastes (intense thermal neutron source, chemistry and materials), advanced application of the ATW concept -- fission energy without a high-level waste stream (overview, advanced technology, and advanced chemistry), and a summary of the research issues.

Not Available

1990-12-31T23:59:59.000Z

397

Using The SLAC Two-Mile Accelerator for Powering an FEL  

Science Conference Proceedings (OSTI)

A parameter survey is made, employing the recently developed 2D formalism for an FEL, of the characteristics of an FEL using the SLAC accelerator. Attention is focused upon a wavelength of 40 {angstrom} (the water window) and 1 {angstrom} case is also presented. They consider employing the SLAC linac with its present operating parameters and with improved parameters such as would be supplied by a new photo-cathode injector. They find that improved parameters are necessary, but that the parameters presently achieved with present-day photo-cathode guns are adequate to reach the water window.

Barletta, W.A.; /LLNL, Livermore; Sessler, A.M.; /LBL, Berkeley; Yu, L.H.; /Brookhaven

2012-06-29T23:59:59.000Z

398

Microwave proton source development for a high-current linac injector  

Science Conference Proceedings (OSTI)

Powerful CW proton linear accelerators (100-mA at 0.5--1.0 GeV) are being proposed for spallation neutron-source applications. A 75-keV, 110-mA dc proton injector using a microwave ion source is being tested for these applications. It has achieved 80-keV, 110-mA hydrogen-ion-beam operation. Video and dc beam-current toroid diagnostics are operational, and an EPICS control system is also operational on the 75-keV injector. A technical base development program has also been carried out on a 50-keV injector obtained from Chalk River Laboratories, and it includes low-energy beam transport studies, ion source lifetime tests, and proton-fraction enhancement studies. Technical base results and the present status of the 75-keV injector will be presented.

Sherman, J.; Bolme, G.; Geisik, C. [Los Alamos National Lab., NM (United States). Accelerator Operations and Technology Div.] [and others

1995-09-01T23:59:59.000Z

399

SLAC National Accelerator Laboratory - 20th Anniversary of a...  

NLE Websites -- All DOE Office Websites (Extended Search)

theoretical work on using linacs and storage rings as drivers for X-ray free electron lasers. But his suggestion that it would be possible to modify and use part of the SLAC linac...

400

SLAC National Accelerator Laboratory - Ultrafast Lasers at the...  

NLE Websites -- All DOE Office Websites (Extended Search)

Lasers at the Linac Coherent Light Source By Alan Fry, LCLS Laser Group July 5, 2011 The Linac Coherent Light Source at SLAC is the world's first hard X-ray free-electron laser, or...

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Optically pulsed electron accelerator  

DOE Patents (OSTI)

An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radiofrequency-powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

Fraser, J.S.; Sheffield, R.L.

1985-05-20T23:59:59.000Z

402

Optically pulsed electron accelerator  

DOE Patents (OSTI)

An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radio frequency powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

Fraser, John S. (Los Alamos, NM); Sheffield, Richard L. (Los Alamos, NM)

1987-01-01T23:59:59.000Z

403

ACCELERATION RESPONSIVE SWITCH  

DOE Patents (OSTI)

An acceleration-responsive device with dual channel capabilities whereby a first circuit is actuated upon attainment of a predetermined maximum acceleration level and when the acceleration drops to a predetermined minimum acceleriltion level another circuit is actuated is described. A fluid-damped sensing mass slidably mounted in a relatively frictionless manner on a shaft through the intermediation of a ball bushing and biased by an adjustable compression spring provides inertially operated means for actuating the circuits. (AEC)

Chabrek, A.F.; Maxwell, R.L.

1963-07-01T23:59:59.000Z

404

TESLA Report 2003-10 Studies of Electromagnetic Cascade Showers Development in the TESLA Main Linac Initiated by Electron Field Emission in RF Cavities  

E-Print Network (OSTI)

this paper, and, in order to see this point more clearly, none of the other possible particle multiplication processes will be included in our simulations. 2 Simulation Procedure and Code Design The process of particle transport in our computer code DUST (DUnkel STrom, in German) is organized in such a way that it naturally breaks down into two parts, Monte Carlo simulation of the electromagnetic shower development when a particle impacts the inner vacuum surface of the accelerator, and particle dynamics in an electromagnetic field inside the accelerator vacuum. As usual, the accelerator to be studied is described as a sequence of physical elements. The user specifies the element geometry, materials and electromagnetic fields. And although we have not implemented something similar to the MAD [20] lattice description language yet, to simplify the accelerator description, elements in our program can be grouped into di#erent modules, from modules one constructs cells, and a sequence of cells forms the linac. 2.1 Particle Transport in Nonvacuum Media When an energetic primary particle incidents on a mass of material of su#cient thickness a cascade of particles and electromagnetic radiation of great complexity results, and the most practical way to obtain the characteristics of this cascade, the distribution and parameters of secondary particles, especially for complicated material geometries, is through Monte Carlo simulations. Even though a code for the transport of high energy particles (in GeV range) can be developed without too great complications (see, for example, [21], [22]), the accurate simulation of the low energy particles is a very demanding e#ort. So, it is obvious, that it is better to use a thoroughly tested, standard programme, based on an extensive and r...

Balandin Brinkmann Flottmann; V. Bal; R. Brinkmann; K. Flöttmann; N. Golubeva

2003-01-01T23:59:59.000Z

405

Fermilab Project X nuclear energy application: Accelerator, spallation target and transmutation technology demonstration  

SciTech Connect

The recent paper 'Accelerator and Target Technology for Accelerator Driven Transmutation and Energy Production' and report 'Accelerators for America's Future' have endorsed the idea that the next generation particle accelerators would enable technological breakthrough needed for nuclear energy applications, including transmutation of waste. In the Fall of 2009 Fermilab sponsored a workshop on Application of High Intensity Proton Accelerators to explore in detail the use of the Superconducting Radio Frequency (SRF) accelerator technology for Nuclear Energy Applications. High intensity Continuous Wave (CW) beam from the Superconducting Radio Frequency (SRF) Linac (Project-X) at beam energy between 1-2 GeV will provide an unprecedented experimental and demonstration facility in the United States for much needed nuclear energy Research and Development. We propose to carry out an experimental program to demonstrate the reliability of the accelerator technology, Lead-Bismuth spallation target technology and a transmutation experiment of spent nuclear fuel. We also suggest that this facility could be used for other Nuclear Energy applications.

Gohar, Yousry; /Argonne; Johnson, David; Johnson, Todd; Mishra, Shekhar; /Fermilab

2011-04-01T23:59:59.000Z

406

Science Accelerator : User Account  

NLE Websites -- All DOE Office Websites (Extended Search)

Energy Office of Science Office of Scientific and Technical Information Website PoliciesImportant Links Science Accelerator science.gov WorldWideScience.org Deep Web Technologies...

407

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

ICFA Beam Dynamics Mini-Workshop on DeflectingCrabbing Cavity Applications in Accelerators April 21-23, 2010, Cockcroft Institute, Daresbury Laboratory, Warrington, UK Sixth...

408

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Welcome Accelerators at Argonne Mission Organization History Document Collection Conferences & Workshops Beams and Applications Seminar Argonne-Fermilab Collaboration Lee Teng...

409

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

(1971). (Located in the Argonne Research Library) Lee Teng Autobiography: Accelerators and I, Beam Dynamics Newsletter, No. 35, p 8-19, December (2004). (Located in Beam...

410

Market Acceleration (Fact Sheet)  

DOE Green Energy (OSTI)

The fact sheet summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its market acceleration subprogram.

Not Available

2010-09-01T23:59:59.000Z

411

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

- Document Access Guide ATLAS: A Proposal for a Precision Heavy Ion Accelerator, Argonne National Laboratory, February (1978). (Located in the DOE Information Bridge) The...

412

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Fermilab Collaboration Lee Teng Scholarship Program Useful Links Argonne Accelerator Institute: For Industrial Collaborators -- Working with Argonne This link is addressed to...

413

The Accelerator Chain  

NLE Websites -- All DOE Office Websites (Extended Search)

Watch video of Fermilab's Accelerators to learn more. Project Contact: Thomas Jordan - jordant@fnal.gov Web Maintainer: qnet-webmaster@fnal.gov Last Update: April 22, 2001...

414

WIPP - CBFO Accelerating Cleanup  

NLE Websites -- All DOE Office Websites (Extended Search)

more information, access DOE Environmental Management site at: http:www.em.doe.govclosure For more information regarding the Accelerating Cleanup: Paths to Closure, contact...

415

Acceleration of polarized protons in circular accelerators  

SciTech Connect

The theory of depolarization in circular accelerators is presented. The spin equation is first expressed in terms of the particle orbit and then converted to the equivalent spinor equation. The spinor equation is then solved for three different situations: (1) a beam on a flat top near a resonance, (2) uniform acceleration through an isolated resonance, and (3) a model of a fast resonance jump. Finally, the depolarization coefficient, epsilon, is calculated in terms of properties of the particle orbit and the results are applied to a calculation of depolarization in the AGS.

Courant, E.D.; Ruth, R.D.

1980-09-12T23:59:59.000Z

416

Method for generating a plasma wave to accelerate electrons  

DOE Patents (OSTI)

The invention provides a method and apparatus for generating large amplitude nonlinear plasma waves, driven by an optimized train of independently adjustable, intense laser pulses. In the method, optimal pulse widths, interpulse spacing, and intensity profiles of each pulse are determined for each pulse in a series of pulses. A resonant region of the plasma wave phase space is found where the plasma wave is driven most efficiently by the laser pulses. The accelerator system of the invention comprises several parts: the laser system, with its pulse-shaping subsystem; the electron gun system, also called beam source, which preferably comprises photo cathode electron source and RF-LINAC accelerator; electron photo-cathode triggering system; the electron diagnostics; and the feedback system between the electron diagnostics and the laser system. The system also includes plasma source including vacuum chamber, magnetic lens, and magnetic field means. The laser system produces a train of pulses that has been optimized to maximize the axial electric field amplitude of the plasma wave, and thus the electron acceleration, using the method of the invention.

Umstadter, Donald (Ann Arbor, MI); Esarey, Eric (Chevy Chase, MD); Kim, Joon K. (Ann Arbor, MI)

1997-01-01T23:59:59.000Z

417

Method for generating a plasma wave to accelerate electrons  

DOE Patents (OSTI)

The invention provides a method and apparatus for generating large amplitude nonlinear plasma waves, driven by an optimized train of independently adjustable, intense laser pulses. In the method, optimal pulse widths, interpulse spacing, and intensity profiles of each pulse are determined for each pulse in a series of pulses. A resonant region of the plasma wave phase space is found where the plasma wave is driven most efficiently by the laser pulses. The accelerator system of the invention comprises several parts: the laser system, with its pulse-shaping subsystem; the electron gun system, also called beam source, which preferably comprises photo cathode electron source and RF-LINAC accelerator; electron photo-cathode triggering system; the electron diagnostics; and the feedback system between the electron diagnostics and the laser system. The system also includes plasma source including vacuum chamber, magnetic lens, and magnetic field means. The laser system produces a train of pulses that has been optimized to maximize the axial electric field amplitude of the plasma wave, and thus the electron acceleration, using the method of the invention. 21 figs.

Umstadter, D.; Esarey, E.; Kim, J.K.

1997-06-10T23:59:59.000Z

418

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

LEUTL: Low Energy Undulator Test Line (operation: 1997-2002) LEUTL: Low Energy Undulator Test Line (operation: 1997-2002) The Low Energy Undulator Test Line (LEUTL) is an experimental hall and associated hardware that was built shortly after the completion of the Advanced Photon Source, and was attached to the APS so that the linac beam could be delivered to the LEUTL hall. LEUTL was configured as a Free Electron Laser (FEL) and was the first experiment to demonstrate Self Amplified Spontaneous Emission in the visible and UV. References - Document Access Guide Description of LEUTL by S. G. Biedron (Argonne National Laboratory Document ) High-Gain Harmonic-Generation Free-Electron Laser, L.-H. Yu, M. Babzien, I. Ben-Zvi, L.F. DiMauro, A. Doyuran, W. Graves, E. Johnson, S. Krinsky, R. Malone, I. Pogorelsky, J. Skaritka, G. Rakowsky, L. Solomon,

419

The Accelerated Universe and the Moon  

E-Print Network (OSTI)

Cosmologically motivated theories that explain small acceleration rate of the Universe via modification of gravity at very large, horizon or super-horizon distances, can be tested by precision gravitational measurements at much shorter scales, such as the Earth-Moon distance. Contrary to the naive expectation the predicted corrections to the Einsteinian metric near gravitating sources are so significant that fall within sensitivity of the proposed Lunar Ranging experiments. The key reason for such corrections is the van Dam-Veltman-Zakharov discontinuity present in linearized versions of all such theories, and its subsequent absence at the non-linear level ala Vainshtein.

Gia Dvali; Andrei Gruzinov; Matias Zaldarriaga

2002-12-04T23:59:59.000Z

420

Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams  

SciTech Connect

Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.

Siemann, R.H.; /SLAC

2011-10-24T23:59:59.000Z

Note: This page contains sample records for the topic "linear accelerator linac" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Microscale acceleration history discriminators  

DOE Patents (OSTI)

A new class of micromechanical acceleration history discriminators is claimed. These discriminators allow the precise differentiation of a wide range of acceleration-time histories, thereby allowing adaptive events to be triggered in response to the severity (or lack thereof) of an external environment. Such devices have applications in airbag activation, and other safety and surety applications.

Polosky, Marc A. (Albuquerque, NM); Plummer, David W. (Albuquerque, NM)

2002-01-01T23:59:59.000Z

422

Dielectric Wakefield Accelerator to drive the future FEL Light Source.  

SciTech Connect

X-ray free-electron lasers (FELs) are expensive instruments and a large part of the cost of the entire facility is driven by the accelerator. Using a high-energy gain dielectric wake-field accelerator (DWA) instead of the conventional accelerator may provide a significant cost saving and reduction of the facility size. In this article, we investigate using a collinear dielectric wakefield accelerator to provide a high repetition rate, high current, high energy beam to drive a future FEL x-ray light source. As an initial case study, a {approx}100 MV/m loaded gradient, 850 GHz quartz dielectric based 2-stage, wakefield accelerator is proposed to generate a main electron beam of 8 GeV, 50 pC/bunch, {approx}1.2 kA of peak current, 10 x 10 kHz (10 beamlines) in just 100 meters with the fill factor and beam loading considered. This scheme provides 10 parallel main beams with one 100 kHz drive beam. A drive-to-main beam efficiency {approx}38.5% can be achieved with an advanced transformer ratio enhancement technique. rf power dissipation in the structure is only 5 W/cm{sup 2} in the high repetition rate, high gradient operation mode, which is in the range of advanced water cooling capability. Details of study presented in the article include the overall layout, the transform ratio enhancement scheme used to increase the drive to main beam efficiency, main wakefield linac design, cooling of the structure, etc.

Jing, C.; Power, J.; Zholents, A. (Accelerator Systems Division (APS)); ( HEP); (LLC)

2011-04-20T23:59:59.000Z

423

Linear Collider Collaboration Tech Notes LCC-0100  

NLE Websites -- All DOE Office Websites (Extended Search)

100 100 August 2002 Systematic Ground Motion and Macroalignment for Linear Colliders Rainer Pitthan Stanford Linear Accelerator Center Stanford University Stanford, CA 94309, USA Abstract: Future colliders with their µm-range operational tolerances still need to be classically aligned to the 50 - 100 µm range, and kept there, over the km range. This requirement will not be a show-stopper, but not be trivial either. 50 µm movements over a betatron wavelength is a the range where systematic long term motions can prevent efficient operation. Systematic Ground Motion and Macro-Alignment for Linear Colliders Complete talk at: http://www-project.slac.stanford.edu/lc/wkshp/snowmass2001/t6/info/pitthan july

424

Detroit as linear city.  

E-Print Network (OSTI)

??Detroit is a city in decline. Through strategic withdrawal into a linear city its main artery -Woodward Avenue- becomes an assembly line that holds different… (more)

Kuys, J.I.

2012-01-01T23:59:59.000Z

425

Linear phase compressive filter  

DOE Patents (OSTI)

A phase linear filter for soliton suppression is in the form of a laddered series of stages of non-commensurate low pass filters with each low pass filter having a series coupled inductance (L) and a reverse biased, voltage dependent varactor diode, to ground which acts as a variable capacitance (C). L and C values are set to levels which correspond to a linear or conventional phase linear filter. Inductance is mapped directly from that of an equivalent nonlinear transmission line and capacitance is mapped from the linear case using a large signal equivalent of a nonlinear transmission line.

McEwan, Thomas E. (Livermore, CA)

1995-01-01T23:59:59.000Z

426

Linear Graphene Plasmons  

Science Conference Proceedings (OSTI)

The coupling of the plasmon spectra of graphene and a nearby thick plasma is examined here in detail. The coupled modes include linear plasmons. Keywords: Graphene, plasmons, surface

N. J.M. Horing

2010-11-01T23:59:59.000Z

427

Design Construction and Test Results of a HTS Solenoid for Energy Recovery Linac  

NLE Websites -- All DOE Office Websites (Extended Search)

DESIGN CONSTRUCTION AND TEST RESULTS OF A HTS SOLENOID DESIGN CONSTRUCTION AND TEST RESULTS OF A HTS SOLENOID FOR ENERGY RECOVERY LINAC* R. Gupta # , M. Anerella, I. Ben-Zvi, G. Ganetis, D. Kayran, G. McIntyre, J. Muratore, S. Plate and W. Sampson, Brookhaven National Laboratory, Upton, NY, 11973 USA and M. Cole and D. Holmes, Advanced Energy Systems, Inc., Medord, NY, 11763 USA Abstract An innovative feature of the proposed Energy Recovery Linac (ERL) is the use of a solenoid made with High Temperature Superconductor (HTS) with the Superconducting RF cavity. The use of HTS allows solenoid to be placed in close proximity to the cavity and thus provides early focusing of the electron beam. In addition, cryogenic testing at ~77 K is simpler and cheaper than 4 K testing. This paper will present the

428

Optimal focusing for a linac-based hard x-ray source  

Science Conference Proceedings (OSTI)

In spite of having a small average beam current limit, a linac can have features that make it attractive as an x-ray source: high energy, ultralow emittance and energy spread, and flexible beamline optics. Unlike a storage ring, in which an (undulator) radiation source is necessarily short and positioned at an electron beam waist, in a linac the undulator can be long and the electron beam can be adjusted to have a (virtual) waist far downstream toward the x-ray target. Using a planned CEBAF beamline as an example, this paper shows that a factor of 2000 in beam current can be overcome to produce a monochromatic hard x-ray source comparable with, or even exceeding, the performance of an x-ray line at a third generation storage ring. Optimal electron beam focusing conditions for x-ray flux density and brilliance are derived, and are verified by simulations using the SRW code.

Liu, C.; Krafft, G.; Talman, R.

2011-03-28T23:59:59.000Z

429

Jar mechanism accelerator  

SciTech Connect

This patent describes an accelerator for use with a jar mechanism in a well pipe string to enhance the jarring impact delivered to a stuck object wherein the jar mechanism includes inner and outer members for connection, respectively, between the well pipe string the stuck object. The jar mechanism members are constructed to (1) restrict relative longitudinal movement therebetween to build up energy in the well pipe string and accelerator and then (2) to release the jar mechanism members for unrestrained, free relative longitudinal movement therebetween to engage jarring surfaces on the jar mechanism members for delivering a jarring impact to the stuck object. The accelerator includes: inner and outer telescopically connected members relatively movable longitudinally to accumulate energy in the accelerator; the inner and outer accelerator members each having means for connecting the accelerator in the well pipe string; means associated with the inner and outer members for initially accomodating a predetermined minimum length of unrestrained, free relative longitudinal movement between the inner and outer accelerator members.

Anderson, E.A.; Webb, D.D.

1989-07-11T23:59:59.000Z

430

PARMTEQ (Phase And Radial Motion in Transverse Electric Quadrupole linacs): A beam dynamics code for the RFQ (radio-frequency quadrupole)  

SciTech Connect

The PARMTEQ code is used for generating the complete cell design of a radio-frequency quadrupole linear accelerator and for multiparticle simulation of the beam dynamics. We present a review of the code, with an emphasis on the physics used to describe the particle motion and the cell generation. 9 refs., 1 fig.

Crandall, K.R.; Wangler, T.P.

1987-01-01T23:59:59.000Z

431

BNL | Accelerating Particles Accelerates Science - With Big Benefits...  

NLE Websites -- All DOE Office Websites (Extended Search)

program focused on developing the next crop of bold accelerator scientists and engineers. Photo of CASE participants The Center for Accelerator Science and Education (CASE)...

432

International linear collider reference design report  

E-Print Network (OSTI)

c current, voltage and stability requirements, and the needand requirements are summarized in Table 3.3-1. Modulators High Voltagerequirements of the main linac are supplied by two high-voltage

Aarons, G.

2008-01-01T23:59:59.000Z

433

Compact Dielectric Wall Accelerator Development For Intensity Modulated Proton Therapy And Homeland Security Applications  

Science Conference Proceedings (OSTI)

Compact dielectric wall (DWA) accelerator technology is being developed at the Lawrence Livermore National Laboratory. The DWA accelerator uses fast switched high voltage transmission lines to generate pulsed electric fields on the inside of a high gradient insulating (HGI) acceleration tube. Its high electric field gradients are achieved by the use of alternating insulators and conductors and short pulse times. The DWA concept can be applied to accelerate charge particle beams with any charge to mass ratio and energy. Based on the DWA system, a novel compact proton therapy accelerator is being developed. This proton therapy system will produce individual pulses that can be varied in intensity, energy and spot width. The system will be capable of being sited in a conventional linac vault and provide intensity modulated rotational therapy. The status of the developmental new technologies that make the compact system possible will be reviewed. These include, high gradient vacuum insulators, solid dielectric materials, SiC photoconductive switches and compact proton sources. Applications of the DWA accelerator to problems in homeland security will also be discussed.

Chen, Y -; Caporaso, G J; Guethlein, G; Sampayan, S; Akana, G; Anaya, R; Blackfield, D; Cook, E; Falabella, S; Gower, E; Harris, J; Hawkins, S; Hickman, B; Holmes, C; Horner, A; Nelson, S; Paul, A; Pearson, D; Poole, B; Richardson, R; Sanders, D; Stanley, J; Sullivan, J; Wang, L; Watson, J; Weir, J

2009-06-17T23:59:59.000Z

434

NDCX-II, an Induction Linac for HEDP and IFE Research  

SciTech Connect

The Heavy Ion Fusion Science Virtual National Laboratory in the USA is constructing a new Neutralized Drift Compression eXperiment (NDCX-II) at LBNL. This facility is being developed for high energy density physics and inertial fusion energy research. The 12 m long induction linac in NDCX-II will produce a Li{sup +} beam pulse, at energies of 1.2-3 MeV, to heat target material to the warm dense matter regime ({approx} 1 eV). By making use of special acceleration voltage waveforms, 2.5T solenoid focusing, and neutralized drift compression, 20 - 50 nC of beam charge from the ion source will be compressed longitudinally and radially to achieve a subnanosecond pulse length and mm-scale target spot size. The original Neutralized Drift Compression Experiment (NDCX-I) has successfully demonstrated simultaneous radial and longitudinal compression by imparting a velocity ramp to the ion beam, which then drifts in a neutralizing plasma to and through the final focussing solenoid and onto the target. At higher kinetic energy and current, NDCX-II will offer more than 100 times the peak energy fluence on target of NDCX-I. NDCX-II makes use of many parts from the decommissioned Advanced Test Accelerator (ATA) at LLNL. It includes 27 lattice periods between the injector and the neutralized drift compression section (Figure 1). There are 12 energized induction cells, 9 inactive cells which provide drift space, and 6 diagnostic cells which provide beam diagnostics and pumping. Custom pulsed power systems generate ramped waveforms for the first 7 induction cells, so as to quickly compress the beam from 600 ns at the injector down to 70 ns. After this compression, the high voltages of the ATA Blumleins are then used to rapidly add energy to the beam. The Blumleins were designed to match the ferrite core volt-seconds with pulses up to 250 kV and a fixed FWHM of 70 ns. The machine is limited to a pulse repetition rate of once every 20 seconds due to cooling requirements. The NDCX-II beam is highly space-charge dominated. The 1-D ASP code was used to synthesize high voltage waveform for acceleration, while the 3-D Warp particle-in-cell code was used for detailed design of the lattice. The Li{sup +} ion was chosen because its Bragg Peak energy (at {approx} 2 MeV) coincides with the NDCX-II beam energy. The 130 keV injector will have a 10.9 cm diameter ion source. Testing of small (0.64 cm diameter) lithium doped alumino-silicate ion sources has demonstrated the current density ({approx} 1 mA/cm{sup 2}) used in the design, with acceptable lifetime. A 7.6 cm diameter source has been successfully produced to verify that the coating method can be applied to such a large emitting area. The ion source will operate at {approx} 1275 C; thus a significant effort was made in the design to manage the 4 kW heating power and the associated cooling requirements. In modifying the ATA induction cells for NDCX-II, the low-field DC solenoids were replaced with 2.5 T pulsed solenoids. The beam pipe diameter was decreased in order to reduce the axial extent of the solenoid fringe fields and to make room for water cooling. In addition, an outer copper cylinder (water-cooled) was used to exclude the solenoid magnetic flux from the ferrite cores. Precise alignment is essential because the beam has a large energy spread due to the rapid pulse compression, such that misalignments lead to corkscrew deformation of the beam and reduced intensity at focus. A novel pulsed-wire measurement method is used to align the pulsed solenoid magnets. Alignment accuracy has been demonstrated to within 100 {micro}m of the induction cell axis. The neutralized drift compression region after the last induction cell is approximately 1.2 m long and includes ferroelectric plasma sources (FEPS) fabricated by PPPL similar to those successfully operating in NDCX-I. The 8-T final focus pulsed solenoid, filtered cathodic arc plasma sources (FCAPS), and target chamber from NDCX-I are to be relocated to NDCX-II. The NDCX-II project started in July 2009 and is expected to complete in fall of 2011.

Kwan, J.W.; Arbelaez, D.; Bieniosek, F.M.; Faltens, A.; Friedman, A.; Galvin, J.; Greenway, W.; Gilson, E. P.; Grote, D. P.; Jung, J.Y.; Lee, E.P.; Leitner, M.; Lidia, S.M.; Logan, B.G.; Lund, S. M.; Reginato, L.L.; Roy, P.K.; Seidl, P.A.; Sharp, W. M.; Takakuwa, J.; Waldron, W.L.

2011-04-20T23:59:59.000Z

435

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

AAI Home AAI Home Welcome Accelerators at Argonne Mission Organization History Document Collection Conferences & Workshops Beams and Applications Seminar Argonne-Fermilab Collaboration Lee Teng Scholarship Program Useful Links Organization The Argonne Accelerator Institute is a matrixed organization. Its members and fellows reside in programmatic Argonne divisions. The Institute reports to the Associate Laboratory Director for Photon Science), and the administrative functions of the Institute are within the PSC directorate. Director: Rodney Gerig Associate Director: Hendrik Weerts ( Director of High Energy Physics Division) Associate Director: Sasha Zholents (Director of Accelerator Systems Division) Associate Director: Robert Janssens ( Director of Argonne Physics Division)

436

Superfund accelerated cleanup model  

SciTech Connect

In an effort to speed and maximize cleanup of the worst sites first, the Environmental Protection Agency (EPA) developed the Superfund Accelerated Cleanup Model (SACM). SACM streamlines the Superfund process so hazardous waste sites can be addressed quicker and in a more cost effective manner. EPA Regional offices developed a number of pilot projects to test the principles of SACM. Although many pilots are underway in the Regions, the pilots described here involve four areas: accelerating cleanup through early actions; integrating site assessments; using Regional Decision Teams to establish priorities; and accelerating cleanup through the use of new technology.

Not Available

1994-08-01T23:59:59.000Z

437

The evolution of high energy accelerators  

SciTech Connect

Accelerators have been devised and built for two reasons: In the first place, by physicists who needed high energy particles in order to have a means to explore the interactions between particles that probe the fundamental elementary forces of nature. And conversely, sometimes accelerator builders produce new machines for higher energy than ever before just because it can be done, and then challenge potential users to make new discoveries with the new means at hand. These two approaches or motivations have gone hand in hand. This lecture traces how high energy particle accelerators have grown from tools used for esoteric small-scale experiments to the gigantic projects of today. So far all the really high-energy machines built and planned in the world--except the SLC--have been ring accelerators and storage rings using the strong-focusing method. But this method has not removed the energy limit, it has only pushed it higher. It would seem unlikely that one can go beyond the Large Hadron Collider (LHC)--but in fact a workshop was held in Sicily in November 1991, concerned with the question of extrapolating to 100 TeV. Other acceleration and beam-forming methods are now being discussed--collective fields, laser acceleration, wake-field accelerators etc., all aimed primarily at making linear colliders possible and more attractive than with present radiofrequency methods. So far it is not entirely clear which of these schemes will dominate particle physics in the future--maybe something that has not been thought of as yet.

Courant, E.D.

1994-08-01T23:59:59.000Z

438

The Particle Adventure | Accelerators and Particle Detectors  

NLE Websites -- All DOE Office Websites (Extended Search)

Waves and particles The world's meterstick Mass and energy Energy-mass conversion Accelerators How to obtain particles to accelerate Accelerating particles Accelerating...

439

Accelerated Aging of Roofing Surfaces  

NLE Websites -- All DOE Office Websites (Extended Search)

Ohio CRRC, Arizona CRRC, Florida CRRC, Ohio 6 | Building Technologies Office eere.energy.gov Approach: develop accelerated aging method Accelerated soiling (atmospheric...

440

Physics Out Loud - Particle Accelerator  

NLE Websites -- All DOE Office Websites (Extended Search)

Nucleus Previous Video (Nucleus) Physics Out Loud Main Index Next Video (Particle Resonance) Particle Resonance Particle Accelerator Andrew Hutton, Director of Accelerators at...

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441

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Quarterly Meetings Quarterly Meetings November 29, 2011 Held at the Advanced Photon Source, Argonne, IL DOE Accelerator R&D Task Force - M. White February 17, 2010 Held at the Advanced Photon Source, Argonne, IL June 16, 2009 General Updates - R. Gerig Accelerator Developments in Physics Division - R. Janssens Proposal for Argonne SRF Facility - M. Kelly Accelerator Developments in HEP Division - W. Gai Beam Activities of the DOD Project Office-Focus on the Navy FEL - S. Biedron AAI Historical Collection - T. Fields November 24, 2008 Strategic Theme Forum Meeting - This meeting was held to gather information on the Accelerator Science and Technology Theme to establish the Argonne's Strategic Plan January 9, 2008 Opening Remarks - R. Gerig ILC Planning - J. Carwardine Argonne Participation in Project X - P. Ostroumov

442

Charged particle accelerator grating  

DOE Patents (OSTI)

A readily disposable and replaceable accelerator grating for a relativistic particle accelerator is described. The grating is formed for a plurality of liquid droplets that are directed in precisely positioned jet streams to periodically dispose rows of droplets along the borders of a predetermined particle beam path. A plurality of lasers are used to direct laser beams onto the droplets, at predetermined angles, thereby to excite the droplets to support electromagnetic accelerating resonances on their surfaces. Those resonances operate to accelerate and focus particles moving along the beam path. As the droplets are distorted or destroyed by the incoming radiation, they are replaced at a predetermined frequency by other droplets supplied through the jet streams.

Palmer, R.B.

1985-09-09T23:59:59.000Z

443

CEBAF accelerator achievements  

Science Conference Proceedings (OSTI)

In the past decade, nuclear physics users of Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) have benefited from accelerator physics advances and machine improvements. As of early 2011, CEBAF operates routinely at 6 GeV, with a 12 GeV upgrade underway. This article reports highlights of CEBAF's scientific and technological evolution in the areas of cryomodule refurbishment, RF control, polarized source development, beam transport for parity experiments, magnets and hysteresis handling, beam breakup, and helium refrigerator operational optimization.

Y.C. Chao, M. Drury, C. Hovater, A. Hutton, G.A. Krafft, M. Poelker, C. Reece, M. Tiefenback

2011-06-01T23:59:59.000Z

444

Accelerating Turing Machines  

Science Conference Proceedings (OSTI)

Accelerating Turing machines are Turing machines of a sort able to perform tasks that are commonly regarded as impossible for Turing machines. For example, they can determine whether or not the decimal representation of ? contains n consecutive 7s, ... Keywords: ?-machine, Chinese room argument, Church–Turing thesis, accelerating Turing machine, decision problem, effective procedure, halting problem, hypercomputation, hypercomputer, infinity machine, oracle machine, super-task

B. Jack Copeland

2002-05-01T23:59:59.000Z

445

Michelson interferometer design for Linac Coherent Light Source (LCLS) applications in the 15 Anstrom to 1.5 Anstrom wavelength range  

E-Print Network (OSTI)

Michelson interferometer design for Linac Coherent Light Source (LCLS) applications in the 15 Anstrom to 1.5 Anstrom wavelength range

Tatchy, R

1999-01-01T23:59:59.000Z

446

About Us: Accelerator Operations and Technology, AOT: LANL  

NLE Websites -- All DOE Office Websites (Extended Search)

About AOT Accelerator and Operations Technology AOT Division provides operations and related support for the Los Alamos Neutron Science Center (LANSCE), conducting fundamental and applied research and development needed to improve its operations support efforts. AOT's R&D efforts include plasma physics, ion beam generation; accelerator physics; linear-accelerator-structure engineering, design; high-space-charge proton-accumulator/compressor-ring physics; beam-transport-lattice physics, engineering; particle-beam-diagnostics physics, engineering; high- and low-power-radio-frequency-system engineering; high-voltage and -current, pulsed-power engineering; magnet-power-system engineering; mechanical engineering, design (e.g., precision alignment technology);

447

High transformer ratio drive beams for wakefield accelerator studies  

Science Conference Proceedings (OSTI)

For wakefield based acceleration schemes, use of an asymmetric (or linearly ramped) drive bunch current profile has been predicted to enhance the transformer ratio and generate large accelerating wakes. We discuss plans and initial results for producing such bunches using the 20 to 23 GeV electron beam at the FACET facility at SLAC National Accelerator Laboratory and sending them through plasmas and dielectric tubes to generate transformer ratios greater than 2 (the limit for symmetric bunches). The scheme proposed utilizes the final FACET chicane compressor and transverse collimation to shape the longitudinal phase space of the beam.

England, R. J.; Ng, C.-K.; Frederico, J.; Hogan, M. J.; Litos, M.; Muggli, P.; Joshi, C.; An, W.; Andonian, G.; Mori, W.; Lu, W. [SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Max Planck Institute for Physics, 80805 Munich (Germany); University of California Los Angeles, Los Angeles, CA 90095 (United States); Tsinghua University, Beijing (China)

2012-12-21T23:59:59.000Z

448

ADJUSTED FIELD PROFILE FOR THE CHROMATICITY CANCELLATION IN FFAG ACCELERATORS.  

SciTech Connect

In an earlier report they have reviewed four major rules to design the lattice of Fixed-Field Alternating-Gradient (FFAG) accelerators. One of these rules deals with the search of the Adjusted Field Profile, that is the field non-linear distribution along the length and the width of the accelerator magnets, to compensate for the chromatic behavior, and thus to reduce considerably the variation of betatron tunes during acceleration over a large momentum range. The present report defines the method for the search of the Adjusted Field Profile.

RUGGIERO, A.G.

2004-10-13T23:59:59.000Z

449

Physics of Laser-driven plasma-based acceleration  

SciTech Connect

The physics of plasma-based accelerators driven by short-pulse lasers is reviewed. This includes the laser wake-field accelerator, the plasma beat wave accelerator, the self-modulated laser wake-field accelerator, and plasma waves driven by multiple laser pulses. The properties of linear and nonlinear plasma waves are discussed, as well as electron acceleration in plasma waves. Methods for injecting and trapping plasma electrons in plasma waves are also discussed. Limits to the electron energy gain are summarized, including laser pulse direction, electron dephasing, laser pulse energy depletion, as well as beam loading limitations. The basic physics of laser pulse evolution in underdense plasmas is also reviewed. This includes the propagation, self-focusing, and guiding of laser pulses in uniform plasmas and plasmas with preformed density channels. Instabilities relevant to intense short-pulse laser-plasma interactions, such as Raman, self-modulation, and hose instabilities, are discussed. Recent experimental results are summarized.

Esarey, Eric; Schroeder, Carl B.

2003-06-30T23:59:59.000Z

450

Steady-State Solutions in Nonlinear Diffusive Shock Acceleration  

E-Print Network (OSTI)

Stationary solutions to the equations of non-linear diffusive shock acceleration play a fundamental role in the theory of cosmic-ray acceleration. Their existence usually requires that a fraction of the accelerated particles be allowed to escape from the system. Because the scattering mean-free-path is thought to be an increasing function of energy, this condition is conventionally implemented as an upper cut-off in energy space -- particles are then permitted to escape from any part of the system, once their energy exceeds this limit. However, because accelerated particles are responsible for substantial amplification of the ambient magnetic field in a region upstream of the shock front, we examine an alternative approach in which particles escape over a spatial boundary. We use a simple iterative scheme that constructs stationary numerical solutions to the coupled kinetic and hydrodynamic equations. For parameters appropriate for supernova remnants, we find stationary solutions with efficient acceleration w...

Reville, B; Duffy, P

2008-01-01T23:59:59.000Z

451