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Author

J. Wolfenden

Other affiliations: University of Liverpool
Bio: J. Wolfenden is an academic researcher from Cockcroft Institute. The author has contributed to research in topics: Conceptual design & Radiation. The author has an hindex of 7, co-authored 24 publications receiving 228 citations. Previous affiliations of J. Wolfenden include University of Liverpool.

Papers
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Journal ArticleDOI
20 Jul 2017
TL;DR: The European Plasma Research Accelerator with eXcellence In Applications (EuPRAXIA) as mentioned in this paper is a European facility with multi-GeV electron beams using plasma as the acceleration medium for photon science, high-energy physics (HEP) detector tests, and other applications such as compact X-ray sources for medical imaging or material processing.
Abstract: The Horizon 2020 Project EuPRAXIA ("European Plasma Research Accelerator with eXcellence In Applications") is preparing a conceptual design report of a highly compact and cost-effective European facility with multi-GeV electron beams using plasma as the acceleration medium. The accelerator facility will be based on a laser and/or a beam driven plasma acceleration approach and will be used for photon science, high-energy physics (HEP) detector tests, and other applications such as compact X-ray sources for medical imaging or material processing. EuPRAXIA started in November 2015 and will deliver the design report in October 2019. EuPRAXIA aims to be included on the ESFRI roadmap in 2020.

79 citations

Journal ArticleDOI
Ralph Assmann, Maria Weikum, Tamina Akhter1, D. Alesini  +269 moreInstitutions (43)
TL;DR: The EuPRAXIA project aims at the construction of an innovative electron accelerator using laser-and electron-beam-driven plasma wakefield acceleration that offers a significant reduction in size and possible savings in cost over current state-of-the-art radiofrequency-based accelerators as discussed by the authors.
Abstract: This report presents the conceptual design of a new European research infrastructure EuPRAXIA. The concept has been established over the last four years in a unique collaboration of 41 laboratories within a Horizon 2020 design study funded by the European Union. EuPRAXIA is the first European project that develops a dedicated particle accelerator research infrastructure based on novel plasma acceleration concepts and laser technology. It focuses on the development of electron accelerators and underlying technologies, their user communities, and the exploitation of existing accelerator infrastructures in Europe. EuPRAXIA has involved, amongst others, the international laser community and industry to build links and bridges with accelerator science — through realising synergies, identifying disruptive ideas, innovating, and fostering knowledge exchange. The Eu-PRAXIA project aims at the construction of an innovative electron accelerator using laser- and electron-beam-driven plasma wakefield acceleration that offers a significant reduction in size and possible savings in cost over current state-of-the-art radiofrequency-based accelerators. The foreseen electron energy range of one to five gigaelectronvolts (GeV) and its performance goals will enable versatile applications in various domains, e.g. as a compact free-electron laser (FEL), compact sources for medical imaging and positron generation, table-top test beams for particle detectors, as well as deeply penetrating X-ray and gamma-ray sources for material testing. EuPRAXIA is designed to be the required stepping stone to possible future plasma-based facilities, such as linear colliders at the high-energy physics (HEP) energy frontier. Consistent with a high-confidence approach, the project includes measures to retire risk by establishing scaled technology demonstrators. This report includes preliminary models for project implementation, cost and schedule that would allow operation of the full Eu-PRAXIA facility within 8—10 years.

77 citations

Journal ArticleDOI
F. Batsch1, Patric Muggli1, R. Agnello2, C. C. Ahdida3, M. C. Amoedo Goncalves3, Y. Andrebe2, O. Apsimon4, Robert Apsimon4, A.-M. Bachmann1, M. A. Baistrukov5, P. Blanchard2, F. Braunmüller1, Philip Burrows6, B. Buttenschön1, Allen Caldwell1, J. Chappell7, Eric Chevallay3, Moses Chung8, D. A. Cooke7, H. Damerau3, C. Davut4, G. Demeter, H. L. Deubner9, S. Doebert3, J. Farmer1, Ambrogio Fasoli2, V. N. Fedosseev3, R. Fiorito4, Ricardo Fonseca10, F. Friebel3, Ivo Furno2, L. Garolfi11, Spencer Gessner3, I. Gorgisyan3, A. A. Gorn5, Eduardo Granados3, M. Granetzny12, T. Graubner9, Olaf Grulke1, Edda Gschwendtner3, V. Hafych1, A. Helm13, J. R. Henderson4, M. Hüther1, I. Yu. Kargapolov5, Sung Youb Kim8, Florian Kraus9, M. Krupa3, Thibaut Lefèvre3, Linbo Liang4, S. Liu11, Nelson Lopes13, Konstantin Lotov5, M. Martyanov1, Stefano Mazzoni3, D. Medina Godoy3, V. A. Minakov5, J. T. Moody1, K. Moon8, P. I. Morales Guzmán1, M. Moreira3, T. Nechaeva1, E. Nowak3, C. Pakuza6, H. Panuganti3, Ans Pardons3, A. Perera4, J. Pucek1, Alexander Pukhov14, Rebecca Ramjiawan3, S. Rey3, K. Rieger1, Oliver Schmitz12, E. Senes3, L. O. Silva13, R. Speroni3, R. I. Spitsyn5, C. Stollberg2, A. Sublet3, A. Topaloudis3, N. Torrado13, P. V. Tuev5, M. Turner3, Francesco Velotti3, L. Verra1, V. A. Verzilov11, Jorge Vieira13, H. Vincke3, Carsten Welsch4, Manfred Wendt3, Matthew Wing7, P. Wiwattananon3, J. Wolfenden4, B. Woolley3, Guoxing Xia4, M. Zepp12, G. Zevi della Porta3 
TL;DR: A relativistic ionization front is used to provide various initial transverse wakefield amplitudes for the self-modulation of a long proton bunch in plasma and it is shown that the phase of the modulation along the bunch is reproducible from event to event, with 3%-7% ( of 2π rms variations allAlong the bunch.
Abstract: We use a relativistic ionization front to provide various initial transverse wakefield amplitudes for the self-modulation of a long proton bunch in plasma. We show experimentally that, with sufficient initial amplitude [≥(4.1±0.4) MV/m], the phase of the modulation along the bunch is reproducible from event to event, with 3%-7% (of 2π) rms variations all along the bunch. The phase is not reproducible for lower initial amplitudes. We observe the transition between these two regimes. Phase reproducibility is essential for deterministic external injection of particles to be accelerated.

29 citations

Journal ArticleDOI
Maria Weikum, T. Akhter, David Alesini, Alexandra Alexandrova1  +162 moreInstitutions (1)
02 Dec 2019
TL;DR: The Horizon 2020 project EuPRAXIA is producing a conceptual design report for a highly compact and cost-effective European facility with multi-GeV electron beams accelerated using plasmas.
Abstract: The Horizon 2020 project EuPRAXIA (European Plasma Research Accelerator with eXcellence In Applications) is producing a conceptual design report for a highly compact and cost-effective European facility with multi-GeV electron beams accelerated using plasmas. EuPRAXIA will be set up as a distributed Open Innovation platform with two construction sites, one with a focus on beam-driven plasma acceleration (PWFA) and another site with a focus on laser-driven plasma acceleration (LWFA). User areas at both sites will provide access to free-electron laser pilot experiments, positron generation and acceleration, compact radiation sources, and test beams for high-energy physics detector development. Support centres in four different countries will complement the pan-European implementation of this infrastructure. (Less)

13 citations


Cited by
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Journal Article
TL;DR: A method, which utilizes the large difference in ionization potentials between successive ionization states of trace atoms, for injecting electrons into a laser-driven wakefield is presented, and a mixture of helium and trace amounts of nitrogen gas was used.
Abstract: A method, which utilizes the large difference in ionization potentials between successive ionization states of trace atoms, for injecting electrons into a laser-driven wakefield is presented. Here a mixture of helium and trace amounts of nitrogen gas was used. Electrons from the K shell of nitrogen were tunnel ionized near the peak of the laser pulse and were injected into and trapped by the wake created by electrons from majority helium atoms and the L shell of nitrogen. The spectrum of the accelerated electrons, the threshold intensity at which trapping occurs, the forward transmitted laser spectrum, and the beam divergence are all consistent with this injection process. The experimental measurements are supported by theory and 3D OSIRIS simulations.

382 citations

Journal ArticleDOI
TL;DR: In this paper, high energy electromagnetic processes in Condensed Media have been studied in the context of high energy electromagnetic processes in the nuclear power plant. But they are not considered in this paper.
Abstract: (1973). High-Energy Electromagnetic Processes in Condensed Media. Nuclear Technology: Vol. 18, No. 3, pp. 312-313.

277 citations

Journal Article
TL;DR: In this article, the focusing strength of a capillary discharge waveguide using laser inverse bremsstrahlung heating was increased to achieve relativistically intense laser pulses with peak power of 0.85 PW over 15 diffraction lengths.
Abstract: Guiding of relativistically intense laser pulses with peak power of 0.85 PW over 15 diffraction lengths was demonstrated by increasing the focusing strength of a capillary discharge waveguide using laser inverse bremsstrahlung heating. This allowed for the production of electron beams with quasimonoenergetic peaks up to 7.8 GeV, double the energy that was previously demonstrated. Charge was 5 pC at 7.8 GeV and up to 62 pC in 6 GeV peaks, and typical beam divergence was 0.2 mrad.

219 citations

Journal Article
Abstract: A theory that describes how to load negative charge into a nonlinear, three-dimensional plasma wakefield is presented. In this regime, a laser or an electron beam blows out the plasma electrons and creates a nearly spherical ion channel, which is modified by the presence of the beam load. Analytical solutions for the fields and the shape of the ion channel are derived. It is shown that very high beam-loading efficiency can be achieved, while the energy spread of the bunch is conserved. The theoretical results are verified with the particle-in-cell code OSIRIS.

173 citations

01 Apr 1992
TL;DR: The nonlinear interaction of ultraintense laser pulses with electron beams and plasmas is rich in a wide variety of new phenomena as discussed by the authors, including laser excitation of large-amplitude plasma waves (wake fields), relativistic optical guiding of laser pulses in preformed plasma channels, laser frequency amplification by ionization fronts and plasma waves, and stimulated backscattering from plasma and electron beams, and cooling of electron beams by intense lasers.
Abstract: The nonlinear interaction of ultraintense laser pulses with electron beams and plasmas is rich in a wide variety of new phenomena. Advances in laser science have made possible compact terawatt lasers capable of generating subpicosecond pulses at ultrahigh powers (≥1 TW) and intensities (≥1018 W/cm2). These ultrahigh intensities result in highly relativistic nonlinear electron dynamics. This paper briefly addresses a number of phenomena including (i) laser excitation of large‐amplitude plasma waves (wake fields), (ii) relativistic optical guiding of laser pulses in plasmas, (iii) optical guiding by preformed plasma channels, (iv) laser frequency amplification by ionization fronts and plasma waves, (v) relativistic harmonic generation, (vi) stimulated backscattering from plasmas and electron beams, (vii) nonlinear Thomson scattering from plasmas and electron beams, and (viii) cooling of electron beams by intense lasers. Potential applications of these effects are also discussed.

141 citations