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1. Application of compact laser-driven accelerator X-ray sources for industrial imaging

Author

Gruse, J.-N., Streeter, M.J.V., Thornton, C., Armstrong, C.D., Baird, C.D., Bourgeois, N., Cipiccia, S., Finlay, O.J., Gregory, C.D., Katzir, Y., Lopes, N.C., Mangles, S.P.D., Najmudin, Z., Neely, D., Pickard, L.R., Potter, K.D., Rajeev, P.P., Rusby, D.R., Underwood, C.I.D., Warnett, J.M., Williams, M.A., Wood, J.C., Murphy, C.D., Brenner, C.M., and Symes, D.R.

Published
2020
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2. Plasma density profile reconstruction of a gas cell for Ionization Induced Laser Wakefield Acceleration

Author

Filippi, F., primary, Dickson, L.T., additional, Backhouse, M., additional, Forestier-Colleoni, P., additional, Gustafsson, C., additional, Cobo, C., additional, Ballage, C., additional, Dobosz Dufrénoy, S., additional, Löfquist, E., additional, Maynard, G., additional, Murphy, C.D., additional, Najmudin, Z., additional, Panza, F., additional, Persson, A., additional, Scisció, M., additional, Vasilovici, O., additional, Lundh, O., additional, and Cros, B., additional

Published
2023
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3. Laser Wakefield Accelerator modelling with Variational Neural Networks

Author

Streeter, M.J.V., primary, Colgan, C., additional, Cobo, C.C., additional, Arran, C., additional, Los, E.E., additional, Watt, R., additional, Bourgeois, N., additional, Calvin, L., additional, Carderelli, J., additional, Cavanagh, N., additional, Dann, S.J.D., additional, Fitzgarrald, R., additional, Gerstmayr, E., additional, Joglekar, A.S., additional, Kettle, B., additional, McKenna, P., additional, Murphy, C.D., additional, Najmudin, Z., additional, Parsons, P., additional, Qian, Q., additional, Rajeev, P.P., additional, Ridgers, C.P., additional, Symes, D.R., additional, Thomas, A.G.R., additional, Sarri, G., additional, and Mangles, S.P.D., additional

Published
2023
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4. Simulation of laser-driven, ablated plasma flows in collisionless shock experiments on OMEGA and the NIF

Author

Grosskopf, M.J., Drake, R.P., Kuranz, C.C., Rutter, E.M., Ross, J.S., Kugland, N.L., Plechaty, C., Remington, B.A., Spitkovsky, A., Gargate, L., Gregori, G., Bell, A., Murphy, C.D., Meinecke, J., Reville, B., Sakawa, Y., Kuramitsu, Y., Takabe, H., Froula, D.H., Fiksel, G., Miniati, F., Koenig, M., Ravasio, A., Liang, E., Fu, W., Woolsey, N., and Park, H.-S.

Published
2013
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5. Modeling HEDLA magnetic field generation experiments on laser facilities

Author

Fatenejad, M., Bell, A.R., Benuzzi-Mounaix, A., Crowston, R., Drake, R.P., Flocke, N., Gregori, G., Koenig, M., Krauland, C., Lamb, D., Lee, D., Marques, J.R., Meinecke, J., Miniati, F., Murphy, C.D., Park, H.-S., Pelka, A., Ravasio, A., Remington, B., Reville, B., Scopatz, A., Tzeferacos, P., Weide, K., Woolsey, N., Young, R., and Yurchak, R.

Published
2013
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8. A laser-plasma platform for photon-photon physics

Author

KETTLE, B., HOLLATZ, D., GERSTMAYR, E., SAMARIN, G.M., ALEJO, A., ASTBURY, S., BAIRD, C., BOHLEN, S., CAMPBELL, M., COLGAN, C., DANNHEIM, D., GREGORY, C., HARSH, H., HATFIELD, P., HINOJOSA, J., KATZIR, Y., MORTON, J., MURPHY, C.D., NURNBERG, A., OSTERHOFF, J., PÉREZ-CALLEJO, G., PÕDER, K., RAJEEV, P.P., ROEDEL, C., ROEDER, F., SALGADO, F.C., SARRI, G., SEIDEL, A., SPANNAGEL, S., SPINDLOE, C., STEINKE, S., STREETER, M.J.V., THOMAS, A.G.R., UNDERWOOD, C., WATT, R., ZEPF, M., ROSE, S.J., MANGLES, S.P.D., Centre d'Etudes Lasers Intenses et Applications (CELIA), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Bordeaux (UB), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), and HEP, INSPIRE

Subjects
Accelerator Physics (physics.acc-ph), [PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex], [PHYS.PHYS.PHYS-GEN-PH] Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], [PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph], FOS: Physical sciences, Physics::Optics, beam transport, laser: wake field, bremsstrahlung, High Energy Physics - Experiment, X-ray, High Energy Physics - Experiment (hep-ex), semiconductor detector: pixel, accelerator: wake field, quantum electrodynamics, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], photon: beam, scintillation counter, plasma, photon photon: scattering, [PHYS.PHYS.PHYS-ACC-PH] Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph], [PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], Physics - Plasma Physics, Plasma Physics (physics.plasm-ph), Physics::Accelerator Physics, Physics - Accelerator Physics
Abstract

We describe a laser-plasma platform for photon-photon collision experiments to measure fundamental quantum electrodynamic processes such as the linear Breit-Wheeler process with real photons. The platform has been developed using the Gemini laser facility at the Rutherford Appleton Laboratory. A laser wakefield accelerator and a bremsstrahlung convertor are used to generate a collimated beam of photons with energies of hundreds of MeV, that collide with keV x-ray photons generated by a laser heated plasma target. To detect the pairs generated by the photon-photon collisions, a magnetic transport system has been developed which directs the pairs onto scintillation-based and hybrid silicon pixel single particle detectors. We present commissioning results from an experimental campaign using this laser-plasma platform for photon-photon physics, demonstrating successful generation of both photon sources, characterisation of the magnetic transport system and calibration of the single particle detectors, and discuss the feasibility of this platform for the observation of the Breit-Wheeler process. The design of the platform will also serve as the basis for the investigation of strong-field quantum electrodynamic processes such as the nonlinear Breit-Wheeler and the Trident process, or eventually, photon-photon scattering., 28 pages, 14 figures

Published
2021

9. A laser-plasma platform for photon-photon physics:The two photon Breit-Wheeler process

Author

Kettle, B., Hollatz, D., Gerstmayr, E., Samarin, G.M., Alejo, A., Astbury, S., Baird, C., Bohlen, S., Campbell, M., Colgan, C., Dannheim, D., Gregory, C., Harsh, H., Hatfield, P., Hinojosa, J., Katzir, Y., Morton, J., Murphy, C.D., Nurnberg, A., Osterhoff, J., Pérez-Callejo, G., Põder, K., Rajeev, P.P., Roedel, C., Roeder, F., Salgado, F.C., Sarri, G., Seidel, A., Spannagel, S., Spindloe, C., Steinke, S., Streeter, M.J.V., Thomas, A.G.R., Underwood, C., Watt, R., Zepf, M., Rose, S.J., Mangles, S.P.D., Kettle, B., Hollatz, D., Gerstmayr, E., Samarin, G.M., Alejo, A., Astbury, S., Baird, C., Bohlen, S., Campbell, M., Colgan, C., Dannheim, D., Gregory, C., Harsh, H., Hatfield, P., Hinojosa, J., Katzir, Y., Morton, J., Murphy, C.D., Nurnberg, A., Osterhoff, J., Pérez-Callejo, G., Põder, K., Rajeev, P.P., Roedel, C., Roeder, F., Salgado, F.C., Sarri, G., Seidel, A., Spannagel, S., Spindloe, C., Steinke, S., Streeter, M.J.V., Thomas, A.G.R., Underwood, C., Watt, R., Zepf, M., Rose, S.J., and Mangles, S.P.D.

Abstract

We describe a laser-plasma platform for photon-photon collision experiments to measure fundamental quantum electrodynamic processes. As an example we describe using this platform to attempt to observe the linear Breit-Wheeler process. The platform has been developed using the Gemini laser facility at the Rutherford Appleton Laboratory. A laser Wakefield accelerator and a bremsstrahlung convertor are used to generate a collimated beam of photons with energies of hundreds of MeV, that collide with keV x-ray photons generated by a laser heated plasma target. To detect the pairs generated by the photon-photon collisions, a magnetic transport system has been developed which directs the pairs onto scintillation-based and hybrid silicon pixel single particle detectors (SPDs). We present commissioning results from an experimental campaign using this laser-plasma platform for photon-photon physics, demonstrating successful generation of both photon sources, characterisation of the magnetic transport system and calibration of the SPDs, and discuss the feasibility of this platform for the observation of the Breit-Wheeler process. The design of the platform will also serve as the basis for the investigation of strong-field quantum electrodynamic processes such as the nonlinear Breit-Wheeler and the Trident process, or eventually, photon-photon scattering. © 2021 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaft

Published
2021

10. A laser-plasma platform for photon-photon physics : The two photon Breit-Wheeler process

Author

Kettle, B., Hollatz, D., Gerstmayr, E., Samarin, G.M., Alejo, A., Astbury, S., Baird, C., Bohlen, S., Campbell, M., Colgan, C., Dannheim, D., Gregory, C., Harsh, H., Hatfield, P., Hinojosa, J., Katzir, Y., Morton, J., Murphy, C.D., Nurnberg, A., Osterhoff, J., Pérez-Callejo, G., Põder, K., Rajeev, P.P., Roedel, C., Roeder, F., Salgado, F.C., Sarri, G., Seidel, A., Spannagel, S., Spindloe, C., Steinke, S., Streeter, M.J.V., Thomas, A.G.R., Underwood, C., Watt, R., Zepf, M., Rose, S.J., Mangles, S.P.D., Kettle, B., Hollatz, D., Gerstmayr, E., Samarin, G.M., Alejo, A., Astbury, S., Baird, C., Bohlen, S., Campbell, M., Colgan, C., Dannheim, D., Gregory, C., Harsh, H., Hatfield, P., Hinojosa, J., Katzir, Y., Morton, J., Murphy, C.D., Nurnberg, A., Osterhoff, J., Pérez-Callejo, G., Põder, K., Rajeev, P.P., Roedel, C., Roeder, F., Salgado, F.C., Sarri, G., Seidel, A., Spannagel, S., Spindloe, C., Steinke, S., Streeter, M.J.V., Thomas, A.G.R., Underwood, C., Watt, R., Zepf, M., Rose, S.J., and Mangles, S.P.D.

Abstract

We describe a laser-plasma platform for photon-photon collision experiments to measure fundamental quantum electrodynamic processes. As an example we describe using this platform to attempt to observe the linear Breit-Wheeler process. The platform has been developed using the Gemini laser facility at the Rutherford Appleton Laboratory. A laser Wakefield accelerator and a bremsstrahlung convertor are used to generate a collimated beam of photons with energies of hundreds of MeV, that collide with keV x-ray photons generated by a laser heated plasma target. To detect the pairs generated by the photon-photon collisions, a magnetic transport system has been developed which directs the pairs onto scintillation-based and hybrid silicon pixel single particle detectors (SPDs). We present commissioning results from an experimental campaign using this laser-plasma platform for photon-photon physics, demonstrating successful generation of both photon sources, characterisation of the magnetic transport system and calibration of the SPDs, and discuss the feasibility of this platform for the observation of the Breit-Wheeler process. The design of the platform will also serve as the basis for the investigation of strong-field quantum electrodynamic processes such as the nonlinear Breit-Wheeler and the Trident process, or eventually, photon-photon scattering. © 2021 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaft

Published
2021

11. Creation and diagnosis of a solid-density plasma with an X-ray free-electron laser

Author

Vinko, S.M., Ciricosta, O., Cho, B.I., Engelhorn, K., Chung, H.-K., Brown, C.R.D., Burian, T., Chalupsky, J., Falcone, R.W., Graves, C., Hajkova, V., Higginbotham, A., Juha, L., Krzywinski, J., Lee, H.J., Messerschmidt, M., Murphy, C.D., Ping, Y., Scherz, A., Schlotter, W., Toleikis, S., Turner, J.J., Vysin, L., Wang, T., Wu, B., Zastrau, U., Zhu, D., Lee, R.W., Heimann, P.A., Nagler, B., and Wark, J.S.

Subjects
X-ray lasers -- Usage, Free electron lasers -- Usage, Plasma (Ionized gases) -- Origin -- Chemical properties -- Atomic properties, High temperature plasmas -- Origin -- Chemical properties -- Atomic properties, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Matter with a high energy density (> [10.sup.5] joules per [cm.sup.3]) is prevalent throughout the Universe, being present in all types of stars (1) and towards the centre of the giant planets (2,3); it is also relevant for inertial confinement fusion (4). Its thermodynamic and transport properties are challenging to measure, requiring the creation of sufficiently long-lived samples at homogeneous temperatures and densities (5,6). With the advent of the Linac Coherent Light Source (LCLS) X-ray laser (7), high-intensity radiation (>[10.sup.17] watts per [cm.sup.2], previously the domain of optical lasers) can be produced at X-ray wavelengths. The interaction of single atoms with such intense X-rays has recently been investigated (8). An understanding of the contrasting case of intense X-ray interaction with dense systems is important from a fundamental viewpoint and for applications. Here we report the experimental creation of a solid-density plasma at temperatures in excess of [10.sup.6] kelvin on inertial-confinement time-scales using an X-ray free-electron laser. We discuss the pertinent physics of the intense X-ray-matter interactions, and illustrate the importance of electron-ion collisions. Detailed simulations of the interaction process conducted with a radiative-collisional code show good qualitative agreement with the experimental results. We obtain insights into the evolution of the charge state distribution of the system, the electron density and temperature, and the timescales of collisional processes. Our results should inform future high-intensity X-ray experiments involving dense samples, such as X-ray diffractive imaging of biological systems, material science investigations, and the study of matter in extreme conditions., The experiment was performed at the LCLS soft X-ray materials science instrument (SXR), where a 1.0-µm-thick aluminium (Al) foil was irradiated with 80-fs X-ray pulses at photon energies in the [...]

Published
2012
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12. Generation of scaled protogalactic seed magnetic fields in laser-produced shock waves

Author

Gregori, G., Ravasio, A., Murphy, C.D., Schaar, K., Baird, A., Bell, A.R., Benuzzi-Mounaix, A., Bingham, R., Constantin, C., Drake, R.P., Edwards, M., Everson, E.T., Gregory, C.D., Kuramitsu, Y., Lau, W., Mithen, J., Niemann, C., Park, H.-S., Remington, B.A., Reville, B., Robinson, A.P.L., Ryutov, D.D., Sakawa, Y., Yang, S., Woolsey, N.C., and Miniati, M. Koenig F.

Subjects
Shock waves -- Properties, Galaxies -- Magnetic properties -- Models, Magnetic fields -- Origin -- Models, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

The standard model for the origin of galactic magnetic fields is through the amplification of seed fields via dynamo or turbulent processes to the level consistent with present observations (1-3). Although other mechanisms may also operate (4,5), currents from misaligned pressure and temperature gradients (the Biermann battery process) inevitably accompany the formation of galaxies in the absence of a primordial field. Driven by geometrical asymmetries in shocks (6) associated with the collapse of protogalactic structures, the Biermann battery is believed to generate tiny seed fields to a level of about [10.sup.-21] gauss (refs 7, 8). With the advent of high-power laser systems in the past two decades, a new area of research has opened in which, using simple scaling relations (9,10), astrophysical environments can effectively be reproduced in the laboratory (11,12). Here we report the results of an experiment that produced seed magnetic fields by the Biermann battery effect. We show that these results can be scaled to the intergalactic medium, where turbulence, acting on timescales of around 700 million years, can amplify the seed fields (13,14) sufficiently to affect galaxy evolution., We conducted these experiments at the Laboratoire pour l'Utilisation de Lasers Intenses (LULI 2000) laser facility. The intense laser was used to illuminate a small carbon rod inside a low-pressure [...]

Published
2012
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13. K-shell spectroscopy of Au plasma generated with a short-pulse laser

Author

Zulick, C., Dollar, F., Chen, H., Falk, K., Gregori, G., Hazi, A., Murphy, C.D., Park, J., Seely, J., Szabo, C.I., Tommasini, R., Shepherd, R., and Krushelnick, K.

Subjects
Lasers in plasma research -- Properties -- Identification and classification -- Composition, Plasma physics -- Research, Gold -- Properties -- Identification and classification, Lasers -- Properties, Plasma (Ionized gases) -- Properties -- Identification and classification -- Composition, Spectrum analysis -- Methods, Laser, Physics
Abstract

The production of X-rays from electron transitions into K-shell vacancies ([K.sub.α,β]) emission) is a well-known process in atomic physics and has been extensively studied as a plasma diagnostic in low- and mid-Z materials. However, X-ray spectra from near neutral high-Z ions are very complex, and their interpretation requires the use of state-of-the-art atomic calculations. In this experiment, the Titan laser system at Lawrence Livermore National Laboratory was used to deliver an approximately 350 J laser pulse, with a 10 ps duration and a wavelength of 1054 nm, to a gold (Au) target. A transparent bent quartz crystal spectrometer with a hard X-ray energy window, ranging from 17 to 102 keV, was used to measure the emission spectrum. [K.sub.α1,α2] and [K.sub.β1,γ1] transitions were observed over a range of target sizes. Additionally, a series of shots were conducted with a pre-ionizing long pulse (3 ns, 1-10 J, 527 nm) on the backside of the target. FLYCHK, an atomic non-LTE code, designed to provide ionization and population distributions, was used to model the experiment. [K.sub.α] / [K.sub.β] ratios were found to be in good agreement with the predicted value for room temperature Au targets. PACS No: 52.38.Ph La production de rayons-X provenant de transitions electroniques dans les lacunes de la couche K (emission [K.sub.α,β]) est un mecanisme bien connu en physique atomique qui a ete tres etudie comme diagnostique de plasma dans les materiaux de Z bas et intermediate. Cependant, les spectres X d'ions de Z eleve presque neutres sont tres complexes et leur interpretation exige l'utilisation de calculs atomiques de pointe. Dans cette experience, nous utilisons le systeme laser Titan du Lawrence Livermore National Laboratory qui envoie environ 350 J par impulsion d'une duree de 10 ps et une longueur d'onde de 1054 nm sur une cible d'or (Au). Nous avons utilise un spectrometre a cristal de quartz courbe avec une fenetre d'entree de rayons-X allant de 17 a 102 keV, afin de mesurer le spectre d'emission. Nous avons observe les transitions [K.sub.α1,α2] et [K.sub.β1,γ1] sur un domaine de grandeur de cible. De plus, une serie d'impulsion pre-ionisante (3 ns, 1-20 J, 527 nm) a ete tiree sur la partie arriere de la cible. Nous avons utilise le code atomique sans equilibre thermodynamique local FLYCHK pour obtenir les distributions d' ionisation et de population, afin de modeliser les resultats experimentaux. Les rapports [K.sub.α] / [K.sub.β] obtenus sont en bon accord avec les valeurs predites pour des cibles d'Au a la temperature de la piece. [Traduit par la Redaction], 1. Introduction The absorption of laser energy during high-intensity shortpulse laser-plasma interactions results in the production of a large current of hot electrons, which can subsequently generate energetic protons, ions, [...]

Published
2011
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14. Application of compact laser-driven accelerator X-ray sources for industrial imaging

Author

Gruse, J.-N, Streeter, Matthew, Thornton, C, Armstrong, C.D., Baird, C.D., Bourgeois, N, Cipiccia, S., Finlay, Oliver, Gregory, C.D., Katzir, Y, Lopes, N.C., Mangles, S.P.D, Najmudin, Z, Neely, D, Pickard, L.R., Potter, K.D., Rajeev, P.P., Rusby, D.R., Underwood, C.I.D, Warnett, J.M., Williams, M.A., Wood, J.C., Murphy, C.D., Brenner, C.M., Symes, D.R., Gruse, J.-N, Streeter, Matthew, Thornton, C, Armstrong, C.D., Baird, C.D., Bourgeois, N, Cipiccia, S., Finlay, Oliver, Gregory, C.D., Katzir, Y, Lopes, N.C., Mangles, S.P.D, Najmudin, Z, Neely, D, Pickard, L.R., Potter, K.D., Rajeev, P.P., Rusby, D.R., Underwood, C.I.D, Warnett, J.M., Williams, M.A., Wood, J.C., Murphy, C.D., Brenner, C.M., and Symes, D.R.

Abstract

X-rays generated by betatron oscillations of electrons in a laser-driven plasma accelerator were characterised and applied to imaging industrial samples. With a 125 TW laser, a low divergence beam with 7.52.6 108 photons mrad−2 per pulse was produced with a synchrotron spectrum with a critical energy of 14.61.3 keV. Radiographs were obtained of a metrology test sample, battery electrodes, and a damage site in a composite material. These results demonstrate the suitability of the source for non-destructive evaluation applications. The potential for industrial implementation of plasma accelerators is discussed.

Published
2020

15. Features of the generation of fast particles from microstructured targets irradiated by high intensity, picosecond laser pulses

Author

Sedov, M.V., primary, Faenov, A.Ya., additional, Andreev, A.A., additional, Skobelev, I.Yu., additional, Ryazantsev, S.N., additional, Pikuz, T.A., additional, Durey, P., additional, Doehl, L., additional, Farley, D., additional, Baird, C.D., additional, Lancaster, K.L., additional, Murphy, C.D., additional, Booth, N., additional, Spindloe, C., additional, Platonov, K.Yu., additional, McKenna, P., additional, Kodama, R., additional, Woolsey, N., additional, and Pikuz, S.A., additional

Published
2019
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17. A spectrometer for ultrashort gamma-ray pulses with photon energies greater than 10 MeV

Author

Behm, K.T., Cole, J.M., Joglekar, A.S., Gerstmayr, E., Wood, J.C., Baird, C.D., Blackburn, T.G., Duff, M., Harvey, C., Ilderton, A., Kuschel, S., Mangles, S.P.D., Marklund, M., McKenna, P., Murphy, C.D., Najmudin, Z., Poder, K., Ridgers, C.P., Sarri, G., Samarin, G.M., Symes, D., Warwick, J., Zepf, M., Krushelnick, K., Thomas, A.G.R., Behm, K.T., Cole, J.M., Joglekar, A.S., Gerstmayr, E., Wood, J.C., Baird, C.D., Blackburn, T.G., Duff, M., Harvey, C., Ilderton, A., Kuschel, S., Mangles, S.P.D., Marklund, M., McKenna, P., Murphy, C.D., Najmudin, Z., Poder, K., Ridgers, C.P., Sarri, G., Samarin, G.M., Symes, D., Warwick, J., Zepf, M., Krushelnick, K., and Thomas, A.G.R.

Abstract

We present a design for a pixelated scintillator based gamma-ray spectrometer for non-linear inverse Compton scattering experiments. By colliding a laser wakefield accelerated electron beam with a tightly focused, intense laser pulse, gamma-ray photons up to 100 MeV energies and with few femtosecond duration may be produced. To measure the energy spectrum and angular distribution, a 33 × 47 array of cesium-iodide crystals was oriented such that the 47 crystal length axis was parallel to the gamma-ray beam and the 33 crystal length axis was oriented in the vertical direction. Using an iterative deconvolution method similar to the YOGI code, modeling of the scintillator response using GEANT4 and fitting to a quantum Monte Carlo calculated photon spectrum, we are able to extract the gamma ray spectra generated by the inverse Compton interaction. © 2018 Author(s).

Published
2018

21. Study of the 44Ti(α, p)47V reaction and implications for core collapse supernovae

Author

Margerin, V., Murphy, A., Davinson, T., Dressler, R., Fallis, J., Kankainen, A., Laird, A.M., Lotay, G., Mountford, D.J., Murphy, C.D., Seiffert, C., Schumann, D., Stowasser, T., Stora, T., Wang, C.H.-T., and Woods, P.J.

Abstract

The underlying physics triggering core collapse supernovae is not fully understood but observations of material ejected during such events helps to solve this puzzle. In particular, several satellite based γ -ray observations of the isotope 44Ti have been reported recently. Conveniently, the amount of thisisotope in stellar ejecta is thought to depend critically on the explosion mechanism. The most influential reaction to the amount of 44Ti in supernovae is 44Ti(α, p)47V. Here we report on a direct study of this reaction conducted at the REX-ISOLDE facility, CERN. The experiment was performed with a 44Ti beam at Elab = 2.16 MeV/u, corresponding to an energy distribution, for reacting α-particles, centred on Ecm = 4.15 with a 1σ width of 0.23 MeV. This is, for the first time, well within the Gamow window for core collapse supernovae. The material from which the 44Ti beam was extracted originates from highlyirradiated components of the SINQ spallation neutron source of the Paul Scherrer Institute. No yield above background was observed, enabling an upper limit for the rate of this reaction to be determined. This result is below expectation, suggesting that the 44Ti(α, p)47V reaction proceeds more slowly thanpreviously thought. Implications for astrophysical events, and remnant age, are discussed.

Published
2014

24. Plasma scale length effects on protons generated in ultra-intense laser–plasmas.

Author

Culfa, O., Tallents, G.J., Korkmaz, M.E., Rossall, A.K., Wagenaars, E., Ridgers, C.P., Murphy, C.D., Booth, N., Carroll, D.C., Wilson, L.A., Lancaster, K.L., and Woolsey, N.C.

Abstract

The energy spectra of protons generated by ultra-intense (1020 W cm−2) laser interactions with a preformed plasma of scale length measured by shadowgraphy are presented. The effects of the preformed plasma on the proton beam temperature and the number of protons are evaluated. Two-dimensional EPOCH particle-in-cell code simulations of the proton spectra are found to be in agreement with measurements over a range of experimental parameters. [ABSTRACT FROM PUBLISHER]

Published
2017
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25. Photon acceleration by laser produced wakefields on Astra

Author

Murphy, C.D., Trines, Raoul M. G. M., Collier, J.L., Divall, E.J., Foster, P.S., Hooker, C.J., Langley, A.J., Smith, J,M., Norreys, P.A., Bingham, Robert, Reitsma, Albert, Gallacher, J. G., Viskup, Richard, Jaroszynski, Dino, Mangles, S.P.D., Najmudin, Z, Thomas, A.G.R., and Krushelnick, K.

Subjects
QC
Abstract

This chapter looks at photon acceleration by laser produced wakefields on Astra

Published
2004

26. Numerical studies of photon acceleration in laser wakefields

Author

Trines, Raoul M. G. M., Murphy, C.D., Bingham, Robert, Mendonca, Jose Tito, Norreys, P.A., and Reitsma, Albert

Subjects
QC
Abstract

This chapter looks at numerical studies of photon acceleration in laser wakefields

Published
2004

27. Electron bunch length measurements from laser-accelerated electrons using single-shot thz time-domain interferometry

Author

Debus, A.D., Bussmann, M., Schramm, U., Sauerbrey, R., Murphy, C.D., Major, Z., Hörlein, R., Veisz, L., Schmid, K., Schreiber, J., Witte, K., Jamison, S.P., Gallacher, J.G., Jaroszynski, D.A., Kaluza, M.C., Hidding, B., Kiselev, S., Heathcote, R., Foster, P.S., Neely, D., Divall, E.J., Hooker, C.J., Smith, J.M., Ertel, K., Langley, A.J., Norreys, P., Collier, J.L., Karsch, S., Debus, A.D., Bussmann, M., Schramm, U., Sauerbrey, R., Murphy, C.D., Major, Z., Hörlein, R., Veisz, L., Schmid, K., Schreiber, J., Witte, K., Jamison, S.P., Gallacher, J.G., Jaroszynski, D.A., Kaluza, M.C., Hidding, B., Kiselev, S., Heathcote, R., Foster, P.S., Neely, D., Divall, E.J., Hooker, C.J., Smith, J.M., Ertel, K., Langley, A.J., Norreys, P., Collier, J.L., and Karsch, S.

Abstract

Laser-plasma wakefield-based electron accelerators are expected to deliver ultrashort electron bunches with unprecedented peak currents. However, their actual pulse duration has never been directly measured in a single-shot experiment. We present measurements of the ultrashort duration of such electron bunches by means of THz time-domain interferometry. With data obtained using a 0.5 J, 45 fs, 800 nm laser and a ZnTe-based electro-optical setup, we demonstrate the duration of laser-accelerated, quasimonoenergetic electron bunches [best fit of 32 fs (FWHM) with a 90% upper confidence level of 38 fs] to be shorter than the drive laser pulse, but similar to the plasma period.

Published
2010

29. The generation of mono-energetic electron beams from ultrashort pulse laser–plasma interactions

Author

Mangles, S.P.D, primary, Krushelnick, K, additional, Najmudin, Z, additional, Wei, M.S, additional, Walton, B, additional, Gopal, A, additional, Dangor, A.E, additional, Fritzler, S, additional, Murphy, C.D, additional, Thomas, A.G.R, additional, Mori, W.B, additional, Gallacher, J, additional, Jaroszynski, D, additional, Norreys, P.A, additional, and Viskup, R, additional

Published
2006
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30. Studies of proton generation and focusing for fast ignition applications

Author

MacKinnon, A.J., primary, Key, M.H., additional, Akli, K., additional, Beg, F., additional, Clarke, R.J., additional, Clark, D., additional, Chen, M.H., additional, Chung, H.-K., additional, Chen, S., additional, Freeman, R.R., additional, Green, J.S., additional, Gu, P., additional, Gregori, G., additional, Highbarger, K., additional, Habara, H., additional, Hatchett, S.P., additional, Hey, D., additional, Heathcote, R., additional, Hill, J.M., additional, King, J.A., additional, Kodama, R., additional, Koch, J.A., additional, Lancaster, K., additional, Lasinski, B.F., additional, Langdon, B., additional, Murphy, C.D., additional, Norreys, P.A., additional, Neely, D., additional, Nakatsutsumi, M., additional, Nakamura, H., additional, Patel, N., additional, Patel, P.K., additional, Pasley, J., additional, Snavely, R.A., additional, Stephens, R.B., additional, Stoeckl, C., additional, Foord, M., additional, Tabak, M., additional, Theobald, W., additional, Storm, M., additional, Tanaka, K., additional, Tampo, M., additional, Tolley, M., additional, Town, R., additional, Wilks, S.C., additional, VanWoerkom, L., additional, Weber, R., additional, Yabuuchi, T., additional, and Zhang, B., additional

Published
2006
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37. There are these moments

Author

Murphy, C.D. Matthew

Subjects
Literature/writing, Women's issues/gender studies
Abstract

There are these moments when we see each other clearly, not due to slanting light or crisp air, but because what's true suddenly asserts itself: the fact of who we [...]

Published
2009

40. Monoenergetic beams of relativistic electrons from intense laser-plasma interactions.

Author

Mangles, S.P.O., Murphy, C.D., Najmudin, Z., Thomas, A.G.R., Collier, J.L., Dangor, A.E., Divall, E.J., Foster, P.S., Gallacher, J.C., Hooker, C.J., Jaroszynski, D.A., Langley, A.J., Mori, W.B., Norreys, P.A., Tsung, F.S., Viskup, R., Walton, B.R., and Krushelnick, K.

Subjects
*RELATIVISTIC particles, *ELECTRON beams, *ELECTRONS, *LASER plasmas, *LASER beams, *PLASMA gases, *RELATIVITY (Physics)
Abstract

High-power lasers that fit into a university-scale laboratory can now reach focused intensities of more than 1019?W?cm-2 at high repetition rates. Such lasers are capable of producing beams of energetic electrons, protons and?-rays. Relativistic electrons are generated through the breaking of large-amplitude relativistic plasma waves created in the wake of the laser pulse as it propagates through a plasma, or through a direct interaction between the laser field and the electrons in the plasma. However, the electron beams produced from previous laser-plasma experiments have a large energy spread, limiting their use for potential applications. Here we report high-resolution energy measurements of the electron beams produced from intense laser-plasma interactions, showing that-under particular plasma conditions-it is possible to generate beams of relativistic electrons with low divergence and a small energy spread (less than three per cent). The monoenergetic features were observed in the electron energy spectrum for plasma densities just above a threshold required for breaking of the plasma wave. These features were observed consistently in the electron spectrum, although the energy of the beam was observed to vary from shot to shot. If the issue of energy reproducibility can be addressed, it should be possible to generate ultrashort monoenergetic electron bunches of tunable energy, holding great promise for the future development of‘table-top’particle accelerators. [ABSTRACT FROM AUTHOR]

Published
2004
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41. Characterization of 7Li(p,n)7Be neutron yields from laser produced ion beams for fast neutron radiography.

Author

Lancaster, K.L., Karsch, S., Habara, H., Beg, F.N., Clark, E.L., Freeman, R., Key, M.H., King, J.A., Kodama, R., Krushelnick, K., Ledingham, K.W.D., McKenna, P., Murphy, C.D., Norreys, P.A., Stephens, R., Stöeckl, C., Toyama, Y., Wei, M.S., and Zepf, M.

Subjects
NEUTRONS, ION bombardment, NEUTRON radiography, THERMAL neutrons, INDUSTRIAL radiography, PHYSICS
Abstract

Investigations of 7Li(p,n)7Be reactions using Cu and CH primary and LiF secondary targets were performed using the VULCAN laser [C.N. Danson et al., J. Mod. Opt. 45, 1653 (1997)] with intensities up to 3×1019 W cm-2. The neutron yield was measured using CR-39 plastic track detector and the yield was up to 3×108 sr-1 for CH primary targets and up to 2×108 sr-1 for Cu primary targets. The angular distribution of neutrons was measured at various angles and revealed a relatively anisotropic neutron distribution over 180° that was greater than the error of measurement. It may be possible to exploit such reactions on high repetition, table-top lasers for neutron radiography. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
2004
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43. Study of electron and proton isochoric heating for fast ignition

Author

Key, M.H., Akli, K., Beg, F., Chen, M.H., Chung, H.-K., Freeman, R.R., Foord, M.E., Green, J.S., Gu, P., Gregori, G., Habara, H., Hatchett, S.P., Hey, D., Hill, J.M, King, J.A., Kodama, R., Koch, J.A., Lancaster, K., Lasinski, B.F., Langdon, B., MacKinnon, A.J., Murphy, C.D., Norreys, P.A., Patel, N., Patel, P., Pasley, J., Snavely, R.A., Stephens, R.B., Stoeckl, C., Tabak, M., Theobald, W., Tanaka, K., Town, R., Wilks, S.C., Yabuuchi, T., Zhang, B., Key, M.H., Akli, K., Beg, F., Chen, M.H., Chung, H.-K., Freeman, R.R., Foord, M.E., Green, J.S., Gu, P., Gregori, G., Habara, H., Hatchett, S.P., Hey, D., Hill, J.M, King, J.A., Kodama, R., Koch, J.A., Lancaster, K., Lasinski, B.F., Langdon, B., MacKinnon, A.J., Murphy, C.D., Norreys, P.A., Patel, N., Patel, P., Pasley, J., Snavely, R.A., Stephens, R.B., Stoeckl, C., Tabak, M., Theobald, W., Tanaka, K., Town, R., Wilks, S.C., Yabuuchi, T., and Zhang, B.

44. High energy electron transport in solids

Author

Stephens, R.B., Snavely, R.P.J., Aglitskii, Y., Akli, K.U., Amiranoff, F., Andersen, C., Batani, D., Baton, S.D., Cowan, T., Freeman, R.R., Green, J.S., Habara, H., Hall, T., Hatchett, S.P., Hey, D.S., Hill, J.M, Kaae, J.L., Key, M.H., King, J.A, Koch, J.A., Kodama, R., Koenig, M., Krushelnick, K., Lancaster, K.L., MacKinnon, A.J., Martinolli, E., Murphy, C.D., Nakatsutsumi, M., Norreys, P., Perelli-Cippo, E., Rabec Le Gloahec, M., Remington, B., Rousseaux, C., Santos, J.J., Scianitti, F., Stoeckl, C., Tabak, M., Tanaka, K.A., Theobald, W., Town, R., Yabuuchi, T., Zhang, B., Stephens, R.B., Snavely, R.P.J., Aglitskii, Y., Akli, K.U., Amiranoff, F., Andersen, C., Batani, D., Baton, S.D., Cowan, T., Freeman, R.R., Green, J.S., Habara, H., Hall, T., Hatchett, S.P., Hey, D.S., Hill, J.M, Kaae, J.L., Key, M.H., King, J.A, Koch, J.A., Kodama, R., Koenig, M., Krushelnick, K., Lancaster, K.L., MacKinnon, A.J., Martinolli, E., Murphy, C.D., Nakatsutsumi, M., Norreys, P., Perelli-Cippo, E., Rabec Le Gloahec, M., Remington, B., Rousseaux, C., Santos, J.J., Scianitti, F., Stoeckl, C., Tabak, M., Tanaka, K.A., Theobald, W., Town, R., Yabuuchi, T., and Zhang, B.

45. Integrated implosion/heating studies for advanced fast ignition

Author

Norreys, P.A., Lancaster, K.L., Murphy, C.D., Habara, H., Karsch, S., Clarke, R.J., Collier, J., Heathcote, R., Hemandez-Gomez, C., Hawkes, S., Neely, D., Hutchinson, M.H.R., Evans, R.G., Borghesi, M., Romagnani, L., Zepf, M., Akli, K., King, J.A., Zhang, B., Freeman, R.R., MacKinnon, A.J., Hatchett, S.P., Patel, P., Snavely, R., Key, M.H., Nikroo, A., Stephens, R., Stoeckl, C., Tanaka, K.A., Norimatsu, T., Toyama, Y., Kodama, R., Norreys, P.A., Lancaster, K.L., Murphy, C.D., Habara, H., Karsch, S., Clarke, R.J., Collier, J., Heathcote, R., Hemandez-Gomez, C., Hawkes, S., Neely, D., Hutchinson, M.H.R., Evans, R.G., Borghesi, M., Romagnani, L., Zepf, M., Akli, K., King, J.A., Zhang, B., Freeman, R.R., MacKinnon, A.J., Hatchett, S.P., Patel, P., Snavely, R., Key, M.H., Nikroo, A., Stephens, R., Stoeckl, C., Tanaka, K.A., Norimatsu, T., Toyama, Y., and Kodama, R.

Abstract

Copyright 2004 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Physics of Plasmas, 11(5), 2746-2753, 2004 and may be found at http://dx.doi.org/10.1063/1.1688790

46. Study of electron and proton isochoric heating for fast ignition

Author

Key, M.H., Akli, K., Beg, F., Chen, M.H., Chung, H.-K., Freeman, R.R., Foord, M.E., Green, J.S., Gu, P., Gregori, G., Habara, H., Hatchett, S.P., Hey, D., Hill, J.M, King, J.A., Kodama, R., Koch, J.A., Lancaster, K., Lasinski, B.F., Langdon, B., MacKinnon, A.J., Murphy, C.D., Norreys, P.A., Patel, N., Patel, P., Pasley, J., Snavely, R.A., Stephens, R.B., Stoeckl, C., Tabak, M., Theobald, W., Tanaka, K., Town, R., Wilks, S.C., Yabuuchi, T., Zhang, B., Key, M.H., Akli, K., Beg, F., Chen, M.H., Chung, H.-K., Freeman, R.R., Foord, M.E., Green, J.S., Gu, P., Gregori, G., Habara, H., Hatchett, S.P., Hey, D., Hill, J.M, King, J.A., Kodama, R., Koch, J.A., Lancaster, K., Lasinski, B.F., Langdon, B., MacKinnon, A.J., Murphy, C.D., Norreys, P.A., Patel, N., Patel, P., Pasley, J., Snavely, R.A., Stephens, R.B., Stoeckl, C., Tabak, M., Theobald, W., Tanaka, K., Town, R., Wilks, S.C., Yabuuchi, T., and Zhang, B.

47. High energy electron transport in solids

Author

Stephens, R.B., Snavely, R.P.J., Aglitskii, Y., Akli, K.U., Amiranoff, F., Andersen, C., Batani, D., Baton, S.D., Cowan, T., Freeman, R.R., Green, J.S., Habara, H., Hall, T., Hatchett, S.P., Hey, D.S., Hill, J.M, Kaae, J.L., Key, M.H., King, J.A, Koch, J.A., Kodama, R., Koenig, M., Krushelnick, K., Lancaster, K.L., MacKinnon, A.J., Martinolli, E., Murphy, C.D., Nakatsutsumi, M., Norreys, P., Perelli-Cippo, E., Rabec Le Gloahec, M., Remington, B., Rousseaux, C., Santos, J.J., Scianitti, F., Stoeckl, C., Tabak, M., Tanaka, K.A., Theobald, W., Town, R., Yabuuchi, T., Zhang, B., Stephens, R.B., Snavely, R.P.J., Aglitskii, Y., Akli, K.U., Amiranoff, F., Andersen, C., Batani, D., Baton, S.D., Cowan, T., Freeman, R.R., Green, J.S., Habara, H., Hall, T., Hatchett, S.P., Hey, D.S., Hill, J.M, Kaae, J.L., Key, M.H., King, J.A, Koch, J.A., Kodama, R., Koenig, M., Krushelnick, K., Lancaster, K.L., MacKinnon, A.J., Martinolli, E., Murphy, C.D., Nakatsutsumi, M., Norreys, P., Perelli-Cippo, E., Rabec Le Gloahec, M., Remington, B., Rousseaux, C., Santos, J.J., Scianitti, F., Stoeckl, C., Tabak, M., Tanaka, K.A., Theobald, W., Town, R., Yabuuchi, T., and Zhang, B.

48. Integrated implosion/heating studies for advanced fast ignition

Author

Norreys, P.A., Lancaster, K.L., Murphy, C.D., Habara, H., Karsch, S., Clarke, R.J., Collier, J., Heathcote, R., Hemandez-Gomez, C., Hawkes, S., Neely, D., Hutchinson, M.H.R., Evans, R.G., Borghesi, M., Romagnani, L., Zepf, M., Akli, K., King, J.A., Zhang, B., Freeman, R.R., MacKinnon, A.J., Hatchett, S.P., Patel, P., Snavely, R., Key, M.H., Nikroo, A., Stephens, R., Stoeckl, C., Tanaka, K.A., Norimatsu, T., Toyama, Y., Kodama, R., Norreys, P.A., Lancaster, K.L., Murphy, C.D., Habara, H., Karsch, S., Clarke, R.J., Collier, J., Heathcote, R., Hemandez-Gomez, C., Hawkes, S., Neely, D., Hutchinson, M.H.R., Evans, R.G., Borghesi, M., Romagnani, L., Zepf, M., Akli, K., King, J.A., Zhang, B., Freeman, R.R., MacKinnon, A.J., Hatchett, S.P., Patel, P., Snavely, R., Key, M.H., Nikroo, A., Stephens, R., Stoeckl, C., Tanaka, K.A., Norimatsu, T., Toyama, Y., and Kodama, R.

Abstract

Copyright 2004 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Physics of Plasmas, 11(5), 2746-2753, 2004 and may be found at http://dx.doi.org/10.1063/1.1688790

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