1
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Arefnia M, Ghorbanalilu M, Niknam AR. Large-amplitude plasma wave generation by laser beating in inhomogeneous magnetized plasmas. Heliyon 2024; 10:e32813. [PMID: 39005921 PMCID: PMC11239589 DOI: 10.1016/j.heliyon.2024.e32813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 06/09/2024] [Accepted: 06/10/2024] [Indexed: 07/16/2024] Open
Abstract
Large-amplitude plasma wave is known to accelerate electrons to high energies. The electron energy gain mainly depends on plasma wave amplitude. In this paper, we investigate the excitation of large-amplitude plasma waves by laser beat-wave in an inhomogeneous plasma. The idea behind this work is to employ linear and radial plasma density profiles to enhance the plasma wave amplitude. PIC simulations are used to validate the numerical solution of the nonlinear wave equation in cylindrical dimensions through the finite difference method. Furthermore, the effects of the quadratic-radial plasma density profiles and magnetic field on the plasma wave excitation are investigated. The study shows that compared to the linear density profile of plasma, the plasma wave amplitude in the case of a linear-radial density profile is far more pronounced. For the linear-radial density profile, the plasma wave amplitude remains steady over greater distances of propagation compared to the linear density profile, resulting in reduced immediate damping effects. It can also be seen that the plasma wave amplitude is higher for the quadratic-radial than for the linear-radial density profiles. The effect of a longitudinal magnetic field on plasma wave amplitude is investigated. It can be seen that the plasma wave amplitude is increased by applying a magnetic field. This study may provide a way to enhance the plasma wave field for accelerating the electrons in laser-plasma accelerators.
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Affiliation(s)
| | | | - Ali Reza Niknam
- Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran
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2
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Sandberg R, Thomas AGR. Dephasingless plasma wakefield photon acceleration. Phys Rev E 2024; 109:025210. [PMID: 38491702 DOI: 10.1103/physreve.109.025210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 01/22/2024] [Indexed: 03/18/2024]
Abstract
Sandberg and Thomas [Phys. Rev. Lett. 130, 085001 (2023)0031-900710.1103/PhysRevLett.130.085001] proposed a scheme to generate ultrashort, high-energy pulses of XUV photons though dephasingless photon acceleration in a beam-driven plasma wakefield. An ultrashort laser pulse is placed in the plasma wake behind a relativistic electron bunch such that it experiences a comoving negative density gradient and therefore shifts up in frequency. Using a tapered density profile provides phase-matching between driver and witness pulses. In this paper, we give the details of the wakefield solutions and phase-matching conditions used to generate the phase-matching density profile. The short, high-density, and weak driver limits are considered. We show, explicitly, the numerical algorithm used to calculate the density profiles.
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Affiliation(s)
- R Sandberg
- Gérard Mourou Center for Ultrafast Optical Sciences, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - A G R Thomas
- Gérard Mourou Center for Ultrafast Optical Sciences, University of Michigan, Ann Arbor, Michigan 48109, USA
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3
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Sandberg RT, Thomas AGR. Photon Acceleration from Optical to XUV. PHYSICAL REVIEW LETTERS 2023; 130:085001. [PMID: 36898096 DOI: 10.1103/physrevlett.130.085001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 10/03/2022] [Accepted: 01/23/2023] [Indexed: 06/18/2023]
Abstract
The propagating density gradients of a plasma wakefield may frequency upshift a trailing witness laser pulse, a process known as "photon acceleration." In uniform plasma, the witness laser will eventually dephase because of group delay. We find phase-matching conditions for the pulse using a tailored density profile. An analytic solution for a 1D nonlinear plasma wake with an electron beam driver indicates that, even though the plasma density decreases, the frequency shift reaches no asymptotic limit, i.e., is unlimited provided the wake can be sustained. In fully self-consistent 1D particle-in-cell (PIC) simulations, more than 40 times frequency shifts were demonstrated. In quasi-3D PIC simulations, frequency shifts up to 10 times were observed, limited only by simulation resolution and nonoptimized driver evolution. The pulse energy increases in this process, by a factor of 5, and the pulse is guided and temporally compressed by group velocity dispersion, resulting in the resulting extreme ultraviolet laser pulse having near-relativistic (a_{0}∼0.4) intensity.
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Affiliation(s)
- R T Sandberg
- Gérard Mourou Center for Ultrafast Optical Sciences, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - A G R Thomas
- Gérard Mourou Center for Ultrafast Optical Sciences, University of Michigan, Ann Arbor, Michigan 48109, USA
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4
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Bohlen S, Brümmer T, Grüner F, Lindstrøm CA, Meisel M, Staufer T, Streeter MJV, Veale MC, Wood JC, D'Arcy R, Põder K, Osterhoff J. In Situ Measurement of Electron Energy Evolution in a Laser-Plasma Accelerator. PHYSICAL REVIEW LETTERS 2022; 129:244801. [PMID: 36563240 DOI: 10.1103/physrevlett.129.244801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 07/22/2022] [Accepted: 10/12/2022] [Indexed: 06/17/2023]
Abstract
We report on a novel, noninvasive method applying Thomson scattering to measure the evolution of the electron beam energy inside a laser-plasma accelerator with high spatial resolution. The determination of the local electron energy enabled the in-situ detection of the acting acceleration fields without altering the final beam state. In this Letter we demonstrate that the accelerating fields evolve from (265±119) GV/m to (9±4) GV/m in a plasma density ramp. The presented data show excellent agreement with particle-in-cell simulations. This method provides new possibilities for detecting the dynamics of plasma-based accelerators and their optimization.
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Affiliation(s)
- S Bohlen
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg and Center for Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - T Brümmer
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - F Grüner
- Universität Hamburg and Center for Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - C A Lindstrøm
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - M Meisel
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg and Center for Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - T Staufer
- Universität Hamburg and Center for Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - M J V Streeter
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Centre for Plasma Physics, School of Mathematics and Physics, Queen's University Belfast, BT7 1NN, Belfast, United Kingdom
| | - M C Veale
- UKRI STFC, Rutherford Appleton Laboratory, Didcot, OX11 0QX, United Kingdom
| | - J C Wood
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - R D'Arcy
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - K Põder
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - J Osterhoff
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
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5
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Chen Q, Maslarova D, Wang J, Lee SX, Horný V, Umstadter D. Transient Relativistic Plasma Grating to Tailor High-Power Laser Fields, Wakefield Plasma Waves, and Electron Injection. PHYSICAL REVIEW LETTERS 2022; 128:164801. [PMID: 35522507 DOI: 10.1103/physrevlett.128.164801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 01/20/2022] [Accepted: 03/21/2022] [Indexed: 06/14/2023]
Abstract
We show the first experiment of a transverse laser interference for electron injection into the laser plasma accelerators. Simulations show such an injection is different from previous methods, as electrons are trapped into later acceleration buckets other than the leading ones. With optimal plasma tapering, the dephasing limit of such unprecedented electron beams could be potentially increased by an order of magnitude. In simulations, the interference drives a relativistic plasma grating, which triggers the splitting of relativistic-intensity laser pulses and wakefield. Consequently, spatially dual electron beams are accelerated, as also confirmed by the experiment.
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Affiliation(s)
- Qiang Chen
- Extreme Light Laboratory, Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Dominika Maslarova
- Institute of Plasma Physics of the Czech Academy of Sciences, Za Slovankou 1782/3, 182 00 Prague, Czech Republic
- Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Břehová 78/7, 115 19 Prague, Czech Republic
| | - Junzhi Wang
- Extreme Light Laboratory, Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Shao Xian Lee
- Extreme Light Laboratory, Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Vojtech Horný
- Department of Physics, Chalmers University of Technology, Fysikgarden 1, 412 58 Gothenburg, Sweden
- LULI-CNRS, École Polytechnique, CEA: Université Paris-Saclay; UPMC Univ Paris 06: Sorbonne Universités, F-91128 Palaiseau Cedex, France
| | - Donald Umstadter
- Extreme Light Laboratory, Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
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6
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Rovige L, Huijts J, Vernier A, Andriyash I, Sylla F, Tomkus V, Girdauskas V, Raciukaitis G, Dudutis J, Stankevic V, Gecys P, Faure J. Symmetric and asymmetric shocked gas jets for laser-plasma experiments. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:083302. [PMID: 34470418 DOI: 10.1063/5.0051173] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 07/26/2021] [Indexed: 06/13/2023]
Abstract
Shocks in supersonic flows offer both high density and sharp density gradients that are used, for instance, for gradient injection in laser-plasma accelerators. We report on a parametric study of oblique shocks created by inserting a straight axisymmetric section at the end of a supersonic "de Laval" nozzle. The effect of different parameters, such as the throat diameter and straight section length on the shock position and density, is studied through computational fluid dynamics (CFD) simulations. Experimental characterizations of a shocked nozzle are compared to CFD simulations and found to be in good agreement. We then introduce a newly designed asymmetric shocked gas jet, where the straight section is only present on one lateral side of the nozzle, thus providing a gas profile well adapted for density transition injection. In this case, full-3D fluid simulations and experimental measurements are compared and show excellent agreement.
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Affiliation(s)
- L Rovige
- Laboratoire d'Optique Appliquée, ENSTA, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, 828 Bv des Maréchaux, 91762 Palaiseau, France
| | - J Huijts
- Laboratoire d'Optique Appliquée, ENSTA, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, 828 Bv des Maréchaux, 91762 Palaiseau, France
| | - A Vernier
- Laboratoire d'Optique Appliquée, ENSTA, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, 828 Bv des Maréchaux, 91762 Palaiseau, France
| | - I Andriyash
- Laboratoire d'Optique Appliquée, ENSTA, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, 828 Bv des Maréchaux, 91762 Palaiseau, France
| | - F Sylla
- SourceLAB, 7 rue de la Croix Martre, 91120 Palaiseau, France
| | - V Tomkus
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, LT-02300 Vilnius, Lithuania
| | - V Girdauskas
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, LT-02300 Vilnius, Lithuania
| | - G Raciukaitis
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, LT-02300 Vilnius, Lithuania
| | - J Dudutis
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, LT-02300 Vilnius, Lithuania
| | - V Stankevic
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, LT-02300 Vilnius, Lithuania
| | - P Gecys
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, LT-02300 Vilnius, Lithuania
| | - J Faure
- Laboratoire d'Optique Appliquée, ENSTA, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, 828 Bv des Maréchaux, 91762 Palaiseau, France
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7
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Sedaghat M, Barzegar S, Niknam AR. Quasi-phase-matched laser wakefield acceleration of electrons in an axially density-modulated plasma channel. Sci Rep 2021; 11:15207. [PMID: 34312453 PMCID: PMC8313720 DOI: 10.1038/s41598-021-94751-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 07/15/2021] [Indexed: 11/20/2022] Open
Abstract
Quasi-phase matching in corrugated plasma channels has been proposed as a way to overcome the dephasing limitation in laser wakefield accelerators. In this study, the phase-lock dynamics of a relatively long electron bunch injected in an axially-modulated plasma waveguide is investigated by performing particle simulations. The main objective here is to obtain a better understanding of how the transverse and longitudinal components of the wakefield as well as the initial properties of the beam affect its evolution and qualities. The results indicate that the modulation of the electron beam generates trains of electron microbunches. It is shown that increasing the initial energy of the electron beam leads to a reduction in its final energy spread and produces a more collimated electron bunch. For larger bunch diameters, the final emittance of the electron beam increases due to the stronger experienced transverse forces and the larger diameter itself. Increasing the laser power improves the maximum energy gain of the electron beam. However, the stronger generated focusing and defocusing fields degrade the collimation of the bunch.
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Affiliation(s)
- M Sedaghat
- Laser and Plasma Research Institute, Shahid Beheshti University, 1983969411, Tehran, Iran
| | - S Barzegar
- Laser and Plasma Research Institute, Shahid Beheshti University, 1983969411, Tehran, Iran
| | - A R Niknam
- Laser and Plasma Research Institute, Shahid Beheshti University, 1983969411, Tehran, Iran.
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8
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Tomkus V, Girdauskas V, Dudutis J, Gečys P, Stankevič V, Račiukaitis G, Gallardo González I, Guénot D, Svensson JB, Persson A, Lundh O. Laser wakefield accelerated electron beams and betatron radiation from multijet gas targets. Sci Rep 2020; 10:16807. [PMID: 33033319 PMCID: PMC7545103 DOI: 10.1038/s41598-020-73805-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/17/2020] [Indexed: 11/10/2022] Open
Abstract
Laser Plasma Wakefield Accelerated (LWFA) electron beams and efficiency of betatron X-ray sources is studied using laser micromachined supersonic gas jet nozzle arrays. Separate sections of the target are used for the injection, acceleration and enhancement of electron oscillation. In this report, we present the results of LWFA and X-ray generation using dynamic gas density grid built by shock-waves of colliding jets. The experiment was done with the 40 TW, 35 fs laser at the Lund Laser Centre. Electron energies of 30–150 MeV and 1.0 × 108–5.5 × 108 photons per shot of betatron radiation have been measured. The implementation of the betatron source with separate regions of LWFA and plasma density grid raised the efficiency of X-ray generation and increased the number of photons per shot by a factor of 2–3 relative to a single-jet gas target source.
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Affiliation(s)
- Vidmantas Tomkus
- Center for Physical Sciences and Technology, 02300, Vilnius, Lithuania.
| | - Valdas Girdauskas
- Center for Physical Sciences and Technology, 02300, Vilnius, Lithuania.,Vytautas Magnus University, 44248, Kaunas, Lithuania
| | - Juozas Dudutis
- Center for Physical Sciences and Technology, 02300, Vilnius, Lithuania
| | - Paulius Gečys
- Center for Physical Sciences and Technology, 02300, Vilnius, Lithuania
| | | | | | | | - Diego Guénot
- Department of Physics, Lund University, 221 00, Lund, Sweden
| | | | - Anders Persson
- Department of Physics, Lund University, 221 00, Lund, Sweden
| | - Olle Lundh
- Department of Physics, Lund University, 221 00, Lund, Sweden
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9
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Adli E, Ahuja A, Apsimon O, Apsimon R, Bachmann AM, Barrientos D, Batsch F, Bauche J, Berglyd Olsen VK, Bernardini M, Bohl T, Bracco C, Braunmüller F, Burt G, Buttenschön B, Caldwell A, Cascella M, Chappell J, Chevallay E, Chung M, Cooke D, Damerau H, Deacon L, Deubner LH, Dexter A, Doebert S, Farmer J, Fedosseev VN, Fiorito R, Fonseca RA, Friebel F, Garolfi L, Gessner S, Gorgisyan I, Gorn AA, Granados E, Grulke O, Gschwendtner E, Hansen J, Helm A, Henderson JR, Hüther M, Ibison M, Jensen L, Jolly S, Keeble F, Kim SY, Kraus F, Li Y, Liu S, Lopes N, Lotov KV, Maricalva Brun L, Martyanov M, Mazzoni S, Medina Godoy D, Minakov VA, Mitchell J, Molendijk JC, Moody JT, Moreira M, Muggli P, Öz E, Pasquino C, Pardons A, Peña Asmus F, Pepitone K, Perera A, Petrenko A, Pitman S, Pukhov A, Rey S, Rieger K, Ruhl H, Schmidt JS, Shalimova IA, Sherwood P, Silva LO, Soby L, Sosedkin AP, Speroni R, Spitsyn RI, Tuev PV, Turner M, Velotti F, Verra L, Verzilov VA, Vieira J, Welsch CP, Williamson B, Wing M, Woolley B, Xia G. Acceleration of electrons in the plasma wakefield of a proton bunch. Nature 2018; 561:363-367. [PMID: 30188496 PMCID: PMC6786972 DOI: 10.1038/s41586-018-0485-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 08/14/2018] [Indexed: 12/03/2022]
Abstract
High-energy particle accelerators have been crucial in providing a deeper understanding of fundamental particles and the forces that govern their interactions. To increase the energy of the particles or to reduce the size of the accelerator, new acceleration schemes need to be developed. Plasma wakefield acceleration1–5, in which the electrons in a plasma are excited, leading to strong electric fields (so called ‘wakefields’), is one such promising acceleration technique. Experiments have shown that an intense laser pulse6–9 or electron bunch10,11 traversing a plasma can drive electric fields of tens of gigavolts per metre and above—well beyond those achieved in conventional radio-frequency accelerators (about 0.1 gigavolt per metre). However, the low stored energy of laser pulses and electron bunches means that multiple acceleration stages are needed to reach very high particle energies5,12. The use of proton bunches is compelling because they have the potential to drive wakefields and to accelerate electrons to high energy in a single acceleration stage13. Long, thin proton bunches can be used because they undergo a process called self-modulation14–16, a particle–plasma interaction that splits the bunch longitudinally into a series of high-density microbunches, which then act resonantly to create large wakefields. The Advanced Wakefield (AWAKE) experiment at CERN17–19 uses high-intensity proton bunches—in which each proton has an energy of 400 gigaelectronvolts, resulting in a total bunch energy of 19 kilojoules—to drive a wakefield in a ten-metre-long plasma. Electron bunches are then injected into this wakefield. Here we present measurements of electrons accelerated up to two gigaelectronvolts at the AWAKE experiment, in a demonstration of proton-driven plasma wakefield acceleration. Measurements were conducted under various plasma conditions and the acceleration was found to be consistent and reliable. The potential for this scheme to produce very high-energy electron bunches in a single accelerating stage20 means that our results are an important step towards the development of future high-energy particle accelerators21,22. Electron acceleration to very high energies is achieved in a single step by injecting electrons into a ‘wake’ of charge created in a 10-metre-long plasma by speeding long proton bunches.
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Affiliation(s)
- E Adli
- University of Oslo, Oslo, Norway
| | | | - O Apsimon
- University of Manchester, Manchester, UK.,Cockcroft Institute, Daresbury, UK
| | - R Apsimon
- Cockcroft Institute, Daresbury, UK.,Lancaster University, Lancaster, UK
| | - A-M Bachmann
- CERN, Geneva, Switzerland.,Max Planck Institute for Physics, Munich, Germany.,Technical University Munich, Munich, Germany
| | | | - F Batsch
- CERN, Geneva, Switzerland.,Max Planck Institute for Physics, Munich, Germany.,Technical University Munich, Munich, Germany
| | | | | | | | - T Bohl
- CERN, Geneva, Switzerland
| | | | | | - G Burt
- Cockcroft Institute, Daresbury, UK.,Lancaster University, Lancaster, UK
| | - B Buttenschön
- Max Planck Institute for Plasma Physics, Greifswald, Germany
| | - A Caldwell
- Max Planck Institute for Physics, Munich, Germany
| | | | | | | | | | | | | | | | - L H Deubner
- Philipps-Universität Marburg, Marburg, Germany
| | - A Dexter
- Cockcroft Institute, Daresbury, UK.,Lancaster University, Lancaster, UK
| | | | - J Farmer
- Heinrich-Heine-University of Düsseldorf, Düsseldorf, Germany
| | | | - R Fiorito
- Cockcroft Institute, Daresbury, UK.,University of Liverpool, Liverpool, UK
| | - R A Fonseca
- ISCTE-Instituto Universitéario de Lisboa, Lisbon, Portugal
| | | | | | | | | | - A A Gorn
- Budker Institute of Nuclear Physics SB RAS, Novosibirsk, Russia.,Novosibirsk State University, Novosibirsk, Russia
| | | | - O Grulke
- Max Planck Institute for Plasma Physics, Greifswald, Germany.,Technical University of Denmark, Lyngby, Denmark
| | | | | | - A Helm
- GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - J R Henderson
- Cockcroft Institute, Daresbury, UK.,Lancaster University, Lancaster, UK
| | - M Hüther
- Max Planck Institute for Physics, Munich, Germany
| | - M Ibison
- Cockcroft Institute, Daresbury, UK.,University of Liverpool, Liverpool, UK
| | | | | | | | | | - F Kraus
- Philipps-Universität Marburg, Marburg, Germany
| | - Y Li
- University of Manchester, Manchester, UK.,Cockcroft Institute, Daresbury, UK
| | - S Liu
- TRIUMF, Vancouver, British Columbia, Canada
| | - N Lopes
- GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - K V Lotov
- Budker Institute of Nuclear Physics SB RAS, Novosibirsk, Russia.,Novosibirsk State University, Novosibirsk, Russia
| | | | - M Martyanov
- Max Planck Institute for Physics, Munich, Germany
| | | | | | - V A Minakov
- Budker Institute of Nuclear Physics SB RAS, Novosibirsk, Russia.,Novosibirsk State University, Novosibirsk, Russia
| | - J Mitchell
- Cockcroft Institute, Daresbury, UK.,Lancaster University, Lancaster, UK
| | | | - J T Moody
- Max Planck Institute for Physics, Munich, Germany
| | - M Moreira
- CERN, Geneva, Switzerland.,GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - P Muggli
- CERN, Geneva, Switzerland.,Max Planck Institute for Physics, Munich, Germany
| | - E Öz
- Max Planck Institute for Physics, Munich, Germany
| | | | | | - F Peña Asmus
- Max Planck Institute for Physics, Munich, Germany.,Technical University Munich, Munich, Germany
| | | | - A Perera
- Cockcroft Institute, Daresbury, UK.,University of Liverpool, Liverpool, UK
| | - A Petrenko
- CERN, Geneva, Switzerland.,Budker Institute of Nuclear Physics SB RAS, Novosibirsk, Russia
| | - S Pitman
- Cockcroft Institute, Daresbury, UK.,Lancaster University, Lancaster, UK
| | - A Pukhov
- Heinrich-Heine-University of Düsseldorf, Düsseldorf, Germany
| | - S Rey
- CERN, Geneva, Switzerland
| | - K Rieger
- Max Planck Institute for Physics, Munich, Germany
| | - H Ruhl
- Ludwig-Maximilians-Universität, Munich, Germany
| | | | - I A Shalimova
- Novosibirsk State University, Novosibirsk, Russia.,Institute of Computational Mathematics and Mathematical Geophysics SB RAS, Novosibirsk, Russia
| | | | - L O Silva
- GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - L Soby
- CERN, Geneva, Switzerland
| | - A P Sosedkin
- Budker Institute of Nuclear Physics SB RAS, Novosibirsk, Russia.,Novosibirsk State University, Novosibirsk, Russia
| | | | - R I Spitsyn
- Budker Institute of Nuclear Physics SB RAS, Novosibirsk, Russia.,Novosibirsk State University, Novosibirsk, Russia
| | - P V Tuev
- Budker Institute of Nuclear Physics SB RAS, Novosibirsk, Russia.,Novosibirsk State University, Novosibirsk, Russia
| | | | | | - L Verra
- CERN, Geneva, Switzerland.,University of Milan, Milan, Italy
| | | | - J Vieira
- GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - C P Welsch
- Cockcroft Institute, Daresbury, UK.,University of Liverpool, Liverpool, UK
| | - B Williamson
- University of Manchester, Manchester, UK.,Cockcroft Institute, Daresbury, UK
| | | | | | - G Xia
- University of Manchester, Manchester, UK.,Cockcroft Institute, Daresbury, UK
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10
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Guillaume E, Döpp A, Thaury C, Ta Phuoc K, Lifschitz A, Grittani G, Goddet JP, Tafzi A, Chou SW, Veisz L, Malka V. Electron Rephasing in a Laser-Wakefield Accelerator. PHYSICAL REVIEW LETTERS 2015; 115:155002. [PMID: 26550730 DOI: 10.1103/physrevlett.115.155002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Indexed: 06/05/2023]
Abstract
An important limit for energy gain in laser-plasma wakefield accelerators is the dephasing length, after which the electron beam reaches the decelerating region of the wakefield and starts to decelerate. Here, we propose to manipulate the phase of the electron beam in the wakefield, in order to bring the beam back into the accelerating region, hence increasing the final beam energy. This rephasing is operated by placing an upward density step in the beam path. In a first experiment, we demonstrate the principle of this technique using a large energy spread electron beam. Then, we show that it can be used to increase the energy of monoenergetic electron beams by more than 50%.
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Affiliation(s)
- E Guillaume
- Laboratoire d'Optique Appliquée, ENSTA ParisTech - CNRS UMR7639 - École Polytechnique, Chemin de la Hunière, 91761 Palaiseau, France
| | - A Döpp
- Laboratoire d'Optique Appliquée, ENSTA ParisTech - CNRS UMR7639 - École Polytechnique, Chemin de la Hunière, 91761 Palaiseau, France
- Centro de Laseres Pulsados, Parque Cientfico, 37185 Villamayor, Salamanca, Spain
| | - C Thaury
- Laboratoire d'Optique Appliquée, ENSTA ParisTech - CNRS UMR7639 - École Polytechnique, Chemin de la Hunière, 91761 Palaiseau, France
| | - K Ta Phuoc
- Laboratoire d'Optique Appliquée, ENSTA ParisTech - CNRS UMR7639 - École Polytechnique, Chemin de la Hunière, 91761 Palaiseau, France
| | - A Lifschitz
- Laboratoire d'Optique Appliquée, ENSTA ParisTech - CNRS UMR7639 - École Polytechnique, Chemin de la Hunière, 91761 Palaiseau, France
| | - G Grittani
- Institute of Physics ASCR, v.v.i. (FZU), ELI Beamlines project, Na Slovance 2, 18221 Prague, Czech Republic
- Czech Technical University in Prague, FNSPE, Brehova 7, 11519 Prague, Czech Republic
| | - J-P Goddet
- Laboratoire d'Optique Appliquée, ENSTA ParisTech - CNRS UMR7639 - École Polytechnique, Chemin de la Hunière, 91761 Palaiseau, France
| | - A Tafzi
- Laboratoire d'Optique Appliquée, ENSTA ParisTech - CNRS UMR7639 - École Polytechnique, Chemin de la Hunière, 91761 Palaiseau, France
| | - S W Chou
- Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany
| | - L Veisz
- Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany
| | - V Malka
- Laboratoire d'Optique Appliquée, ENSTA ParisTech - CNRS UMR7639 - École Polytechnique, Chemin de la Hunière, 91761 Palaiseau, France
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11
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Golovin G, Banerjee S, Zhang J, Chen S, Liu C, Zhao B, Mills J, Brown K, Petersen C, Umstadter D. Tomographic imaging of nonsymmetric multicomponent tailored supersonic flows from structured gas nozzles. APPLIED OPTICS 2015; 54:3491-3497. [PMID: 25967342 DOI: 10.1364/ao.54.003491] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report experimental results on the production and characterization of asymmetric and composite supersonic gas flows, created by merging independently controllable flows from multiple nozzles. We demonstrate that the spatial profiles are adjustable over a large range of parameters, including gas density, density gradient, and atomic composition. The profiles were precisely characterized using three-dimensional tomography. The creation and measurement of complex gas flows is relevant to numerous applications, ranging from laser-produced plasmas to rocket thrusters.
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12
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Liu M, Deng A, Xia C, Liu J, Wang C, Li R, Xu Z. Influence of pointing fluctuation on intense laser beams propagation in plasma channels. OPTICS EXPRESS 2010; 18:8077-8086. [PMID: 20588652 DOI: 10.1364/oe.18.008077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
An off-axis incident model is presented to analyze the influence of beam pointing fluctuation on the propagation properties of intense laser beams in plasma channels. The equations for the beam spot size and centroid are obtained by applying the variational method. The beam pointing fluctuation contributes additional focusing effect by amplifying relativistic self-focusing, leading to periodically modified oscillations of the spot size. The beam centroid oscillates along the channel axis with the amplitude close to its initial off-axis displacement, while the oscillation frequency is scaled as the square of the dimensionless channel strength parameter.
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Affiliation(s)
- Mingwei Liu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, ChineseAcademy of Sciences, Shanghai 201800, China
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13
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Zhu X. Ultrashort high quality electron beam from laser wakefield accelerator using two-step plasma density profile. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:033307. [PMID: 20370170 DOI: 10.1063/1.3360927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
In this paper, we first use the rf linac injector mechanism to generate ultrashort high quality electron beam from laser wakefield accelerator (LWFA) with two-step plasma density profile successfully. We incorporate the physics principle in the conventional rf linac injector into the LWFA by using two-step plasma density to decrease the wavelength of the wakefield in plasma. Using this mechanism, we observe a ultrashort high quality electron beam (the rms energy spread is 1.9%, and the rms bunch length is 2 fs) in the simulation. The ultrashort intense terahertz coherent radiation (200 MW, 2 fs) can be generated with the proposed laser wakefield accelerator.
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Affiliation(s)
- Xiongwei Zhu
- Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
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14
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Trines RMGM. Wave-breaking limits for nonquasistatic oscillations in a warm one-dimensional electron plasma. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 79:056406. [PMID: 19518575 DOI: 10.1103/physreve.79.056406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Indexed: 05/27/2023]
Abstract
In this work, wave breaking for general non-quasi-static oscillations in warm plasma is investigated using Lagrangian methods. In particular, the effects of secular behavior on wave-breaking limits are explored, and it is shown that thermal effects can sometimes prevent wave breaking by curbing secular behavior. The oscillation equations for fully relativistic warm plasma are cast into Lagrangian form, and wave-breaking limits are derived for waves in warm plasma having nonconstant density. These results have important applications in electron acceleration schemes that employ a wakefield or a slow beat wave propagating down a density gradient.
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Affiliation(s)
- R M G M Trines
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, United Kingdom
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15
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Leemans W, Esarey E, Geddes C, Schroeder C, Tóth C. Laser guiding for GeV laser-plasma accelerators. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2006; 364:585-600. [PMID: 16483950 DOI: 10.1098/rsta.2005.1724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
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 at Lawrence Berkeley National Laboratory (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 accelerator, together with loading of the accelerating structure with beam, is the key to production of mono-energetic electron beams. Increasing the energy towards a GeV and beyond will require reducing the plasma density and design criteria are discussed for an optimized accelerator module. The current progress and future directions are summarized through comparison with conventional accelerators, highlighting the unique short-term prospects for intense radiation sources based on laser-driven plasma accelerators.
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Affiliation(s)
- Wim Leemans
- Lawrence Berkeley National Laboratory LOASIS Program, Accelerator and Fusion Research Division Berkeley, CA 94720, USA.
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16
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Gordon DF, Hubbard RF, Cooley JH, Hafizi B, Ting A, Sprangle P. Quasimonoenergetic electrons from unphased injection into channel guided laser wakefield accelerators. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 71:026404. [PMID: 15783426 DOI: 10.1103/physreve.71.026404] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2004] [Revised: 11/11/2004] [Indexed: 05/24/2023]
Abstract
A high-quality electron beam can be extracted from a channel guided laser wakefield accelerator without confining the injected particles to a small region of phase. By careful choice of the injection energy, a regime can be found where uniformly phased particles are quickly bunched by the accelerator itself and subsequently accelerated to high energy. The process is particularly effective in a plasma channel because of a favorable phase shift that occurs in the focusing fields. Furthermore, particle-in-cell simulations show that the self-fields of the injected bunches actually tend to reduce the energy spread on the final beam. The final beam characteristics can be calculated using a computationally inexpensive Hamiltonian formulation when beam-loading effects are minimal.
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Affiliation(s)
- D F Gordon
- Naval Research Laboratory, Plasma Physics Division, Washington, D.C. 20375, USA
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17
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Tsung FS, Narang R, Mori WB, Joshi C, Fonseca RA, Silva LO. Near-GeV-energy laser-wakefield acceleration of self-injected electrons in a centimeter-scale plasma channel. PHYSICAL REVIEW LETTERS 2004; 93:185002. [PMID: 15525172 DOI: 10.1103/physrevlett.93.185002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2003] [Indexed: 05/24/2023]
Abstract
The first three-dimensional, particle-in-cell (PIC) simulations of laser-wakefield acceleration of self-injected electrons in a 0.84 cm long plasma channel are reported. The frequency evolution of the initially 50 fs (FWHM) long laser pulse by photon interaction with the wake followed by plasma dispersion enhances the wake which eventually leads to self-injection of electrons from the channel wall. This first bunch of electrons remains spatially highly localized. Its phase space rotation due to slippage with respect to the wake leads to a monoenergetic bunch of electrons with a central energy of 0.26 GeV after 0.55 cm propagation. At later times, spatial bunching of the laser enhances the acceleration of a second bunch of electrons to energies up to 0.84 GeV before the laser pulse intensity is significantly reduced.
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Affiliation(s)
- F S Tsung
- Department of Physics and Astronomy, University of California-Los Angeles, Los Angeles, CA 90095, USA
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18
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Sprangle P, Peñano JR, Hafizi B, Kapetanakos CA. Ultrashort laser pulses and electromagnetic pulse generation in air and on dielectric surfaces. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2004; 69:066415. [PMID: 15244753 DOI: 10.1103/physreve.69.066415] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2003] [Revised: 03/02/2004] [Indexed: 05/24/2023]
Abstract
Intense, ultrashort laser pulses propagating in the atmosphere have been observed to emit sub-THz electromagnetic pulses (EMPS). The purpose of this paper is to analyze EMP generation from the interaction of ultrashort laser pulses with air and with dielectric surfaces and to determine the efficiency of conversion of laser energy to EMP energy. In our self-consistent model the laser pulse partially ionizes the medium, forms a plasma filament, and through the ponderomotive forces associated with the laser pulse, drives plasma currents which are the source of the EMP. The propagating laser pulse evolves under the influence of diffraction, Kerr focusing, plasma defocusing, and energy depletion due to electron collisions and ionization. Collective effects and recombination processes are also included in the model. The duration of the EMP in air, at a fixed point, is found to be a few hundred femtoseconds, i.e., on the order of the laser pulse duration plus the electron collision time. For steady state laser pulse propagation the flux of EMP energy is nonradiative and axially directed. Radiative EMP energy is present only for nonsteady state or transient laser pulse propagation. The analysis also considers the generation of EMP on the surface of a dielectric on which an ultrashort laser pulse is incident. For typical laser parameters, the power and energy conversion efficiency from laser radiation to EMP radiation in both air and from dielectric surfaces is found to be extremely small, < 10(-8). Results of full-scale, self-consistent, numerical simulations of atmospheric and dielectric surface EMP generation are presented. A recent experiment on atmospheric EMP generation is also simulated.
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Affiliation(s)
- P Sprangle
- Naval Research Laboratory, Plasma Physics Division, Washington, DC 20375, USA
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19
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Kim JU, Hafz N, Suk H. Electron trapping and acceleration across a parabolic plasma density profile. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2004; 69:026409. [PMID: 14995568 DOI: 10.1103/physreve.69.026409] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2003] [Indexed: 05/24/2023]
Abstract
It is known that as a laser wakefield passes through a downward density transition in a plasma some portion of the background electrons are trapped in the laser wakefield and the trapped electrons are accelerated to relativistic high energies over a very short distance. In this study, by using a two-dimensional (2D) particle-in-cell (PIC) simulation, we suggest an experimental scheme that can manipulate electron trapping and acceleration across a parabolic plasma density channel, which is easier to produce and more feasible to apply to the laser wakefield acceleration experiments. In this study, 2D PIC simulation results for the physical characteristics of the electron bunches that are emitted from the parabolic density plasma channel are reported in great detail.
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Affiliation(s)
- J U Kim
- Korea Electrotechnology Research Institute, Center for Advanced Accelerators, 28-1 Seongju-dong, Changwon 641-120, Korea.
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20
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Gordon DF, Hafizi B, Hubbard RF, Peñano JR, Sprangle P, Ting A. Asymmetric self-phase modulation and compression of short laser pulses in plasma channels. PHYSICAL REVIEW LETTERS 2003; 90:215001. [PMID: 12786561 DOI: 10.1103/physrevlett.90.215001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2002] [Indexed: 05/24/2023]
Abstract
A relativistically intense femtosecond laser pulse propagating in a plasma channel undergoes dramatic photon deceleration while propagating a distance on the order of a dephasing length. The deceleration of photons is localized to the back of the pulse and is accompanied by compression and explosive growth of the ponderomotive potential. Fully explicit particle-in-cell simulations are applied to the problem and are compared with ponderomotive guiding center simulations. A numerical Wigner transform is used to examine local frequency shifts within the pulse and to suggest an experimental diagnostic of plasma waves inside a capillary.
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Affiliation(s)
- D F Gordon
- Icarus Research, Inc, PO Box 30780, Bethesda, Maryland 20824-0780, USA
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21
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Peñano JR, Hafizi B, Sprangle P, Hubbard RF, Ting A. Raman forward scattering and self-modulation of laser pulses in tapered plasma channels. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2002; 66:036402. [PMID: 12366262 DOI: 10.1103/physreve.66.036402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2002] [Indexed: 05/23/2023]
Abstract
The propagation of intense laser pulses with durations longer than the plasma period through tapered plasma channels is investigated theoretically and numerically. General propagation equations are presented and reduced partial differential equations that separately describe the forward Raman (FR) and self-modulation (SM) instabilities in a nonuniform plasma are derived. Local dispersion relations for FR and SM instabilities are used to analyze the detuning process arising from a longitudinal density gradient. Full-scale numerical fluid simulations indicate parameters that favorably excite either the FR or SM instability. The suppression of the FR instability and the enhancement of the SM instability in a tapered channel in which the density increases longitudinally is demonstrated. For a pulse undergoing a self-modulation instability, calculations show that the phase velocity of the wakefield in an untapered channel can be significantly slower than the pulse group velocity. Simulations indicate that this wake slippage can be forestalled through the use of a tapered channel.
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Affiliation(s)
- J R Peñano
- Plasma Physics Division, Beam Physics Branch, Naval Research Laboratory, Washington, D.C. 20375, USA
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22
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Andreev NE, Nishida Y, Yugami N. Propagation of short intense laser pulses in gas-filled capillaries. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2002; 65:056407. [PMID: 12059715 DOI: 10.1103/physreve.65.056407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2001] [Indexed: 05/23/2023]
Abstract
The guided laser pulse propagation and wake-field generation are studied in a wide (in comparison with the laser spot size) gas-filled capillary with an on-axis gas density depletion, which can be produced by a rapid spin of the capillary around its axis or by radially propagating shock waves generated in a piezoceramic tube. A single equation for the wake-field potential, which describes the fully relativistic plasma response in the presence of optical field ionization (OFI) of a gas, is derived and used to demonstrate a guided propagation of a short intense laser pulse over many Rayleigh lengths in a leaky plasma channel produced by the pulse due to OFI in the capillary filled with a radially inhomogeneous gas. The efficient generation of a regular wake field over long distances suitable for the laser wake-field accelerators is shown.
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Affiliation(s)
- N E Andreev
- Institute for High Energy Densities, Associated Institute for High Temperatures, Russian Academy of Sciences, Izhorskaya 13/19, Moscow 127412, Russia.
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