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in creator/contributor: "Schroeder, C."

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Health and safety impacts of nuclear, geothermal, and fossil-fuel electric generation in California. Volume 5. Control of population densities surrounding nuclear power plants

In view of the requirement that the California Energy Resources Conservation and Development Commission must specify land-use/population-density control measures to be used in the vicinity of nuclear power plants being granted land use, the possible forms of such measures are examined. Since these measures must maintain population densities below Nuclear Regulatory Commission criteria, if appropriate, NRC criteria for land use and population densities are given particular attention. In addition… more

Date: January 1, 1977

Creator: Nero, A. V.; Schroeder, C. H. & Yen, W. W. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Studies of a Free Electron Laser Driven by a Laser-Plasma Accelerator

A free electron laser (FEL) uses an undulator, a set of alternating magnets producing a periodic magnetic fi eld, to stimulate emission of coherent radiation from a relativistic electron beam. The Lasers, Optical Accelerator Systems Integrated Studies (LOASIS) group at Lawrence Berkeley National Laboratory (LBNL) will use an innovative laserplasma wakefi eld accelerator to produce an electron beam to drive a proposed FEL. In order to optimize the FEL performance, the dependence on electron beam… more

Date: January 1, 2008

Creator: Montgomery, A.; Schroeder, C. & Fawley, W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A solubility model for amorphous silica in concentrated electrolytes

Silica is one of the major constituents of the earth`s crust and is ubiquitously present in most natural materials. The solubility of silica and other silica-containing compounds is, therefore, of primary concern in geochemistry and in chemical processing applications where silica scale formation, resulting from changes in temperature and electrolyte composition, can cause problems in process design and operation. This paper describes the development of an aqueous thermodynamic model for accura… more

Date: August 1, 1994

Creator: Felmy, A. R.; Schroeder, C. C. & Mason, M. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Physical Fidelity in Particle-In-Cell Modeling of Small Debye-Length Plasmas

The connection between macro-particle shape functions and non-physical phase-space"heating" in the particle-in-cell (PIC) algorithm is examined. The development of fine-scale phasespace structures starting from a cold initial condition is shown to be related to spatial correlations in the interpolated fields used in the Lorentz force. It is shown that the plasma evolution via the PIC algorithm from a cold initial condition leads to a state that is not consistent with that of a thermal… more

Date: August 1, 2008

Creator: Shadwick, B. A. & Schroeder, C. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Electron beam conditioning by Thomson scattering

A method is proposed for conditioning electron beams via Thomson scattering. The conditioning provides a quadratic correlation between the electron energy deviation and the betatron amplitude of the electrons, which results in enhanced gain in free-electron lasers. Quantum effects imply conditioning must occur at high laser fluence and moderate electron energy. Conditioning of x-ray free-electron lasers should be achievable with present laser technology, leading to significant size and cost red… more

Date: November 25, 2003

Creator: Schroeder, C. B.; Esarey, E. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Warm Wavebreaking of Nonlinear Plasma Waves With Arbitrary Phase Velocities

A warm, relativistic fluid theory of a nonequilibrium, collisionless plasma is developed to analyze nonlinear plasma waves excited by intense drive beams. The maximum amplitude and wavelength are calculated for nonrelativistic plasma temperatures and arbitrary plasma wave phase velocities. The maximum amplitude is shown to increase in the presence of a laser field. These results set a limit to the achievable gradient in plasma-based accelerators.

Date: November 12, 2004

Creator: Schroeder, C. B.; Esarey, E. & Shadwick, B. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Raman forward scattering of high-intensity chirped laser pulses

Raman forward scattering of a high-intensity, short-duration, frequency-chirped laser pulse propagating in an underdense plasma is examined. The growth of the direct forward scattered light is calculated for a laser pulse with a linear frequency chirp in various spatio-temporal regimes. This includes a previously undescribed regime of strongly-coupled four-wave nonresonant interaction, which is important for relativistic laser intensities. In all regimes of forward scattering, it is shown that … more

Date: June 23, 2002

Creator: Schroeder, C. B.; Esarey, E.; Shadwick, B. A. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Raman forward scattering of chirped laser pulses

Raman scattering of a high-intensity, short duration, frequency-chirped laser pulse propagating in an underdense plasma is examined. The growth of the direct forward scattered light is calculated for a laser pulse with a linear frequency chirp in various spatio-temporal regimes. This includes a previously undescribed regime of strongly-coupled four-wave nonresonant interaction, which is important for relativistic laser intensities. In all regimes of forward scattering, it is shown that the grow… more

Date: December 5, 2002

Creator: Schroeder, C. B.; Esarey, E.; Shadwick, B. A. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Nonlinear Laser Energy Depletion in Laser-Plasma Accelerators

Energy depletion of intense, short-pulse lasers via excitation of plasma waves is investigated numerically and analytically. The evolution of a resonant laser pulse proceeds in two phases. In the first phase, the pulse steepens, compresses, and frequency red-shifts as energy is deposited in the plasma. The second phase of evolution occurs after the pulse reaches a minimum length at which point the pulse rapidly lengthens, losing resonance with the plasma. Expressions for the rate of laser energ… more

Date: April 3, 2009

Creator: Shadwick, B. A.; Schroeder, C. B. & Esarey, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Improvement of electron beam quality in optical injection schemesusing negative plasma density gradients

Enhanced electron trapping using plasma density down ramps as a method for improving the performance of laser injection schemes is proposed and analyzed. A decrease in density implies an increase in plasma wavelength, which can shift a relativistic electron from the defocusing to the focusing region of the accelerating wakefield, and a decrease in wake phase velocity, which lowers the trapping threshold. The specific method of two-pulse colliding pulse injector was examined using a three-dimens… more

Date: July 26, 2005

Creator: Fubiani, G.; Esarey, E.; Schroeder, C. B. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Laser Guiding for GeV Laser-Plasma Accelerators

Guiding of relativistically intense laser beams in preformed plasma channels is discussed for development of GeV-class laser accelerators. Experiments using a channel guided laser wakefield accelerator (LWFA) at LBNL have demonstrated that near mono-energetic 100 MeV-class electron beams can be produced with a 10 TW laser system. Analysis, aided by particle-in-cell simulations, as well as experiments with various plasma lengths and densities, indicate that tailoring the length of the accelerato… more

Date: June 6, 2005

Creator: Leemans, Wim; Esarey, Eric; Geddes, Cameron; Schroeder, C.B. & Toth, Csaba

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Pulse shape and spectrum of coherent diffraction-limited transition radiation from electron beams

The electric field in the temporal and spectral domain of coherent diffraction-limited transition radiation is studied. An electron bunch, with arbitrary longitudinal momentum distribution, propagating at normal incidence to a sharp metal-vacuum boundary with finite transverse dimension is considered. A general expression for the spatiotemporal electric field of the transition radiation is derived, and closed-form solutions for several special cases are given. The influence of parameters such a… more

Date: December 20, 2003

Creator: van Tilborg, J.; Schroeder, C. B.; Esarey, E. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Tapered plasma channels to phase-lock accelerating and focusing forces in laser-plasma accelerators

Tapered plasma channels are considered for controlling dephasing of a beam with respect to a plasma wave driven by a weakly-relativistic, short-pulse laser. Tapering allows for enhanced energy gain in a single laser plasma accelerator stage. Expressions are derived for the taper, or longitudinal plasma density variation, required to maintain a beam at a constant phase in the longitudinal and/or transverse fields of the plasma wave. In a plasma channel, the phase velocities of the longitudinal a… more

Date: May 17, 2010

Creator: Rittershofer, W.; Schroeder, C. B.; Esarey, E.; Gruner, F. J. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Efficient Modeling of Laser-Plasma Accelerators with INF&RNO

The numerical modeling code INF&RNO (INtegrated Fluid& paRticle simulatioN cOde, pronounced"inferno") is presented. INF&RNO is an efficient 2D cylindrical code to model the interaction of a short laser pulse with an underdense plasma. The code is based on an envelope model for the laser while either a PIC or a fluid description can be used for the plasma. The effect of the laser pulse on the plasma is modeled with the time-averaged poderomotive force. These and other featu… more

Date: June 1, 2010

Creator: Benedetti, C.; Schroeder, C. B.; Esarey, E.; Geddes, C. G. R. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Efficient Electron Injection Into Plasma Waves Using Higher-Orderlaser Modes

Using higher-order transverse laser modes as drivers forplasma wave excitation, and, in particular, using a ring laser beam withmaximum intensity off-axis, results in reversal of the focusinganddefocusing phase regions in a laser wakefield accelerator. Thisresults in improved performance of self-trapping and laser injectionschemes. Specifically, the trapping threshold required foropticalinjection is decreased and the maximum energy gain of the trappedelectrons is increased. This scheme could al… more

Date: August 2, 2006

Creator: Michel, P.; Esarey, E.; Schroeder, C. B.; Shadwick, B. A. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Space-charge effects in ultra-high current electron bunches generated by laser-plasma accelerators

Recent advances in laser-plasma accelerators, including the generation of GeV-scale electron bunches, enable applications such as driving a compact free-electron-laser (FEL). Significant reduction in size of the FEL is facilitated by the expected ultra-high peak beam currents (10-100 kA) generated in laser-plasma accelerators. At low electron energies such peak currents are expected to cause space-charge effects such as bunch expansion and induced energy variations along the bunch, potentially … more

Date: February 11, 2009

Creator: Grinner, F. J.; Schroeder, C. B.; Maier, A. R.; Becker, S. & Mikhailova, J. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

LASER-PLASMA-ACCELERATOR-BASED GAMMA GAMMA COLLIDERS

Design considerations for a next-generation linear collider based on laser-plasma-accelerators are discussed, and a laser-plasma-accelerator-based gamma-gamma collider is considered. An example of the parameters for a 0.5 TeV laser-plasma-accelerator gamma gamma collider is presented.

Date: May 4, 2009

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

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Design considerations for a laser-plasma linear collider

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.

Date: August 1, 2008

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

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Thermal effects in plasma-based accelerators

Finite plasma temperature can modify the structure of thewake field, reduce the wave-breaking field, and lead to self-trappedelectrons, which can degrade the electron bunch quality in a plasma-basedaccelerator. A relativistic warm fluid theory is used to describe theplasma temperature evolution and alterations to the structure of anonlinear periodic wave exited in a warm plasma. The trapping thresholdfor a plasma electron and the fraction of electrons trapped from athermal distribution are exam… more

Date: January 9, 2007

Creator: Esarey, E.; Schroeder, C. B.; Michel, E.; Shadwick, B. A.; Geddes, C. G. R. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Design of a free-electron laser driven by the LBNLlaser-plasma-accelerator

We discuss the design and current status of a compactfree-electron laser (FEL), generating ultra-fast, high-peak flux, VUVpulses driven by a high-current, GeV electron beam from the existingLawrence Berkeley National Laboratory (LBNL) laser-plasma accelerator,whose active acceleration length is only a few cm. The proposedultra-fast source would be intrinsically temporally synchronized to thedrive laser pulse, enabling pump-probe studies in ultra-fast science withpulse lengths of tens of fs. Owi… more

Date: September 10, 2007

Creator: Schroeder, C. B.; Fawley, W. M.; Montgomery, A. L.; Robinson, K. E.; Gruner, F.; Bakeman, M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Design Considerations for Plasma Accelerators Driven by Lasers or Particle Beams

Plasma accelerators may be driven by the ponderomotive force of an intense laser or the space-charge force of a charged particle beam. The implications for accelerator design and the different physical mechanisms of laser-driven and beam-driven plasma acceleration are discussed. Driver propagation is examined, as well as the effects of the excited plasma wave phase velocity. The driver coupling to subsequent plasma accelerator stages for high-energy physics applications is addressed.

Date: June 1, 2010

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

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Beat wave injection of electrons into plasma waves using two interfering laser pulses

An electron injector concept that uses a single injection laser pulse colliding with a pump laser pulse in a plasma is analyzed. The pump pulse generates a large amplitude laser wakefield (plasma wave). The counter propagating injection pulse collides with the pump laser pulse to generate a beat wave with a slow phase velocity. The ponderomotive force of the slow beat wave is responsible for injecting plasma electrons into the wakefield near the back of the pump pulse. Test particle simulations… more

Date: March 4, 2004

Creator: Fubiani, G.; Esarey, E.; Schroeder, C. B. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Single-shot spatio-temporal measurements of high-field terahertzpulses

The electric field profiles of broad-bandwidth coherentterahertz (THz) pulses, emitted by laserwakefield-accelerated electronbunches, are studied. The near-single-cycle THz pulses are measured withtwo single-shot techniques in the temporal and spatial domains. Spectraof 0 - 6 THz and peak fields up to ~; 0.4 MVcm-1 are observed. Themeasured field substructure demonstrates the manifestation ofspatio-temporal coupling at focus, which affects the interpretation ofTHz radiation as a bunch diagnosti… more

Date: May 29, 2006

Creator: van Tilborg, J.; Schroeder, C. B.; Toth, Cs.; Geddes, C. G. R.; Esarey, E. & Leemans, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The Origin of Mass

No Description Available.

Date: July 25, 2013

Creator: Boyle, P.; Buchoff, M.; Christ, N.; Izubuchi, T.; Jung, C.; Luu, T. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department