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in creator/contributor: "Geddes, C.G.R."

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Modeling of 10 GeV-1 TeV laser-plasma accelerators using Lorentz booster simulations

Modeling of laser-plasma wakefield accelerators in an optimal frame of reference [J.-L. Vay, Phys. Rev. Lett. 98 130405 (2007)] allows direct and e#14;fficient full-scale modeling of deeply depleted and beam loaded laser-plasma stages of 10 GeV-1 TeV (parameters not computationally accessible otherwise). This verifies the scaling of plasma accelerators to very high energies and accurately models the laser evolution and the accelerated electron beam transverse dynamics and energy spread. Over 4,… more

Date: December 1, 2011

Creator: Vay, J. L.; Geddes, C. G. R.; Esarey, E.; Esarey, E.; Leemans, W. P.; Cormier-Michel, E. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Effects of Hyperbolic Rotation in Minkowski Space on the Modeling of Plasma Accelerators in a Lorentz Boosted Frame

Laser driven plasma accelerators promise much shorter particle accelerators but their development requires detailed simulations that challenge or exceed current capabilities. We report the first direct simulations of stages up to 1 TeV from simulations using a Lorentz boosted calculation frame resulting in a million times speedup, thanks to a frame boost as high as gamma = 1300. Effects of the hyperbolic rotation in Minkowski space resulting from the frame boost on the laser propagation in the … more

Date: September 21, 2010

Creator: Vay, J. L.; Geddes, C. G. R.; Cormier-Michel, E. & Grote, D. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Modeling laser wakefield accelerators in a Lorentz boosted frame

Modeling of laser-plasma wakefield accelerators in an optimal frame of reference [1] is shown to produce orders of magnitude speed-up of calculations from first principles. Obtaining these speedups requires mitigation of a high frequency instability that otherwise limits effectiveness in addition to solutions for handling data input and output in a relativistically boosted frame of reference. The observed high-frequency instability is mitigated using methods including an electromagnetic solver … more

Date: September 15, 2010

Creator: Vay, J. L.; Geddes, C. G. R.; Cormier-Michel, E. & Grote, D. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Modeling laser wakefield accelerators in a Lorentz boosted frame

Modeling of laser-plasma wakefield accelerators in an optimal frame of reference is shown to produce orders of magnitude speed-up of calculations from first principles. Obtaining these speedups requires mitigation of a high-frequency instability that otherwise limits effectiveness in addition to solutions for handling data input and output in a relativistically boosted frame of reference. The observed high-frequency instability is mitigated using methods including an electromagnetic solver with… more

Date: June 15, 2010

Creator: Vay, J. L.; Geddes, C. G. R.; Cormier-Michel, E. & Grotec, D. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The BErkeley Lab Laser Accelerator (BELLA): A 10 GeV Laser Plasma Accelerator

An overview is presented of the design of a 10 GeV laser plasma accelerator (LPA) that will be driven by a PW-class laser system and of the BELLA Project, which has as its primary goal to build and install the required Ti:sapphire laser system for the acceleration experiments. The basic design of the 10 GeV stage aims at operation in the quasi-linear regime, where the laser excited wakes are largely sinusoidal and offer the possibility of accelerating both electrons and positrons. Simulations s… more

Date: June 1, 2010

Creator: Leemans, W. P.; Duarte, R.; Esarey, E.; Fournier, S.; Geddes, C. G. R.; Lockhart, D. 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

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

Laser-PlasmaWakefield Acceleration with Higher Order Laser Modes

Laser-plasma collider designs point to staging of multiple accelerator stages at the 10 GeV level, which are to be developed on the upcoming BELLA laser, while Thomson Gamma source designs use GeV stages, both requiring efficiency and low emittance. Design and scaling of stages operating in the quasi-linear regime to address these needs are presented using simulations in the VORPAL framework. In addition to allowing symmetric acceleration of electrons and positrons, which is important for colli… more

Date: June 1, 2010

Creator: Geddes, C. G. R.; Cormier-Michel, E.; Esarey, E.; Schroeder, C. B.; Mullowney, P.; Paul, K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Summary Report of Working Group 1: Laser-Plasma Acceleration

Advances in and physics of the acceleration of particles using underdense plasma structures driven by lasers were the topics of presentations and discussions in Working Group 1 of the 2010 Advanced Accelerator Concepts Workshop. Such accelerators have demonstrated gradients several orders beyond conventional machines, with quasi-monoenergetic beams at MeV-GeV energies, making them attractive candidates for next generation accelerators. Workshop discussions included advances in control over inje… more

Date: June 1, 2010

Creator: Geddes, C.G.R.; Clayton, C.; Lu, W. & Thomas, A.G.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ultrafast Diagnostics for Electron Beams from Laser Plasma Accelerators

We present an overview of diagnostic techniques for measuring key parameters of electron bunches from Laser Plasma Accelerators (LPAs). The diagnostics presented here were chosen because they highlight the unique advantages (e.g., diverse forms of electromagnetic emission) and difficulties (e.g., shot-to-shot variability) associated with LPAs. Non destructiveness and high resolution (in space and time and energy) are key attributes that enable the formation of a comprehensive suite of simultane… more

Date: June 1, 2010

Creator: Matlis, N. H.; Bakeman, M.; Geddes, C. G. R.; Gonsalves, T.; Lin, C.; Nakamura, K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Wavefront Measurement for Laser-Guiding Diagnostic

The wavefront of a short laser pulse after interaction in a laser-plasma accelerator (LPA) was measured to diagnose laser-guiding quality. Experiments were performed on a 100 TW class laser at the LOASIS facility of LBNL using a hydrogenfilled capillary discharge waveguide. Laser-guiding with a pre-formed plasma channel allows the laser pulse to propagate over many Rayleigh lengths at high intensity and is crucial to accelerate electrons to the highest possible energy. Efficient coupling of las… more

Date: June 1, 2010

Creator: Chicago, University of; Laboratory, Lawrence Berkeley National; Shiraishi, S.; Gonsalves, A. J.; Lin, C.; Nakamura, K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Plasma channel diagnostic based on laser centroid oscillations

A technique has been developed for measuring the properties of discharge-based plasma channels by monitoring the centroid location of a laser beam exiting the channel as a function of input alignment offset between the laser and the channel. Experiments were performed using low-intensity (<10<sup>14</sup> Wcm<sup>-2</sup>) laser pulses focused onto the entrance of a hydrogen-filled capillary discharge waveguide. Scanning the laser centroid position at the input of the channel and recording the … more

Date: May 1, 2010

Creator: Gonsalves, A. J.; Nakamura, K.; Lin, C.; Osterhoff, J.; Shiraishi, S.; Schroeder, C. B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Design of 10 GeV laser wakefield accelerator stages with shaped laser modes

We present particle-in-cell simulations, using the VORPAL framework, of 10 GeV laser plasma wakefield accelerator stages. Scaling of the physical parameters with the plasma density allows us to perform these simulations at reasonable cost and to design high performance stages. In particular we show that, by choosing to operate in the quasi-linear regime, we can use higher order laser modes to tailor the focusing forces. This makes it possible to increase the matched electron beam radius and hen… more

Date: September 25, 2009

Creator: Cormier-Michel, Estelle; Esarey, E.; Geddes, C. G. R.; Geddes, C. G. R.; Leemans, W. P.; Bruhwiler, D. L. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Experimental study of self-trapping in capillary discharge guided laser wakefield acceleration

Laser wakefield acceleration experiments were carried out using hydrogen-filled capillary discharge waveguides. For a 33 mm long, 300 mu m capillary, parameter regimes with high energy electron beams (up to 1 GeV) and stable 0.5 GeV were found. In the high energy regime, the electron beam peak energy was correlated with the number of trapped electrons. For a 15 mm long, 200 mu m diameter capillary, quasi-monoenergetic e beams up to 300 MeV were observed. By de-tuning discharge delay from optimu… more

Date: May 4, 2009

Creator: Panasenko, D.; Esarey, E.; Geddes, C. G. R.; Gonsalves, A. J.; Leemans, W. P.; Lin, C. et al.

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

OPTIMIZATION AND SINGLE-SHOT CHARACTERIZATION OF ULTRASHORT THz PULSES FROM A LASER WAKEFIELD ACCELERATOR

We present spatiotemporal characterization of J-class ultrashort THz pulses generated from a laser wakefield accelerator (LWFA). Accelerated electrons, resulting from the interaction of a high-intensity laser pulse with a plasma, emit high-intensity THz pulses as coherent transition radiation. Such high peak-power THz pulses, suitable for high-field (MV/cm) pump-probe experiments, also provide a non-invasive bunch-length diagnostic and thus feedback for the accelerator. The characterization of … more

Date: May 4, 2009

Creator: Plateau, G. R.; Matlis, N. H.; van Tilborg, J.; Geddes, C. G. R.; Toth, Cs.; Schroeder, C. B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Scaled Simulation Design of High Quality Laser Wakefield Accelerator Stages

Design of efficient, high gradient laser driven wakefield accelerator (LWFA) stages using explicit particle-incell simulations with physical parameters scaled by plasma density is presented. LWFAs produce few percent energy spread electron bunches at 0.1-1 GeV with high accelerating gradients. Design tools are now required to predict and improve performance and efficiency of future LWFA stages. Scaling physical parameters extends the reach of explicit simulations to address applications includi… more

Date: May 4, 2009

Creator: Geddes, C. G. R.; Cormier-Michel, E.; Esarey, E.; Schroeder, C. B.; Leemans, W. P.; Bruhwiler, D. L. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Application of the Reduction of Scale Range in a Lorentz Boosted Frame to the Numerical Simulation of Particle Acceleration Devices

It has been shown [1] that it may be computationally advantageous to perform computer simulations in a boosted frame for a certain class of systems: particle beams interacting with electron clouds, free electron lasers, and laser-plasma accelerators. However, even if the computer model relies on a covariant set of equations, it was also pointed out that algorithmic difficulties related to discretization errors may have to be overcome in order to take full advantage of the potential speedup [2] … more

Date: May 1, 2009

Creator: Vay, J. L.; Fawley, W. M.; Geddes, C. G. R.; Cormier-Michel, E. & Grote, D. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Recent results and future challenges for large scale Particle-In-Cell simulations of plasma-based accelerator concepts

The concept and designs of plasma-based advanced accelerators for high energy physics and photon science are modeled in the SciDAC COMPASS project with a suite of Particle-In-Cell codes and simulation techniques including the full electromagnetic model, the envelope model, the boosted frame approach and the quasi-static model. In this paper, we report the progress of the development of these models and techniques and present recent results achieved with large-scale parallel PIC simulations. The… more

Date: May 1, 2009

Creator: Huang, C.; An, W.; Decyk, V. K.; Lu, W.; Mori, W. B.; Tsung, F. S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Simulating relativistic beam and plasma systems using an optimal boosted frame

It was shown recently that it may be computationally advantageous to perform computer simulations in a Lorentz boosted frame for a certain class of systems. However, even if the computer model relies on a covariant set of equations, it was pointed out that algorithmic difficulties related to discretization errors may have to be overcome in order to take full advantage of the potential speedup. In this paper, we summarize the findings, the difficulties and their solutions, and review the applica… more

Date: May 1, 2009

Creator: Vay, J. L.; Bruhwiler, D. L.; Geddes, C. G. R.; Fawley, W. M.; Martins, S. F.; Cary, J. R. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Betatron radiation from density tailored plasmas

In laser wakefield accelerators, electron motion is driven by intense forces that depend on the plasma density. Transverse oscillations in the accelerated electron orbits produce betatron radiation. The electron motion and the resulting betatron radiation spectrum can therefore be controlled by shaping the plasma density along the orbit of the electrons. Here, a method based on the use of a plasma with a longitudinal density variation (density depression or step) is proposed to increase the tra… more

Date: April 11, 2009

Creator: Ta Phuoc, Kim; Esarey, E.; Leurent, V.; Cormier-Michel, E.; Geddes, C. G. R.; Schroeder, C. B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Progress on laser plasma accelerator development using transverselyand longitudinally shaped plasmas

A summary of progress at Lawrence Berkeley National Laboratory is given on: (1) experiments on down-ramp injection; (2) experiments on acceleration in capillary discharge plasma channels; and (3) simulations of a staged laser wakefield accelerator (LWFA). Control of trapping in a LWFA using plasma density down-ramps produced electron bunches with absolute longitudinal and transverse momentum spreads more than ten times lower than in previous experiments (0.17 and 0.02 MeV Ic FWHM, respectively)… more

Date: March 31, 2009

Creator: Leemans, Wim P.; Esarey, E.; Geddes, C.G.R.; Toth, Cs.; Schroeder, C.B.; Nakamura, K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Speeding Up Simulations of Relativistic Systems using an Optimal Boosted Frame

It can be computationally advantageous to perform computer simulations in a Lorentz boosted frame for a certain class of systems. However, even if the computer model relies on a covariant set of equations, it has been pointed out that algorithmic difficulties related to discretization errors may have to be overcome in order to take full advantage of the potential speedup. We summarize the findings, the difficulties and their solutions, and show that the technique enables simulations important t… more

Date: January 27, 2009

Creator: Vay, J. L.; Fawley, W. M.; Geddes, C. G. R.; Cormier-Michel, E. & Grote, D. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

New Developments in the Simulation of Advanced Accelerator Concepts

Improved computational methods are essential to the diverse and rapidly developing field of advanced accelerator concepts. We present an overview of some computational algorithms for laser-plasma concepts and high-brightness photocathode electron sources. In particular, we discuss algorithms for reduced laser-plasma models that can be orders of magnitude faster than their higher-fidelity counterparts, as well as important on-going efforts to include relevant additional physics that has been pre… more

Date: September 10, 2008

Creator: Paul, K.; Cary, J. R.; Cowan, B.; Bruhwiler, D. L.; Geddes, C. G. R.; Mullowney, P. J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department