Search Results - "O’Shea, F. H."

Generation of Ramped Current Profiles in Relativistic Electron Beams Using Wakefields in Dielectric Structures by Andonian, G, Barber, S, O'Shea, F H, Fedurin, M, Kusche, K, Swinson, C, Rosenzweig, J B

“…Temporal pulse tailoring of charged-particle beams is essential to optimize efficiency in collinear wakefield acceleration schemes. In this Letter, we…”
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Demonstration of Single-Shot Picosecond Time-Resolved MeV Electron Imaging Using a Compact Permanent Magnet Quadrupole Based Lens by Cesar, D, Maxson, J, Musumeci, P, Sun, Y, Harrison, J, Frigola, P, O'Shea, F H, To, H, Alesini, D, Li, R K

“…We present the results of an experiment where a short focal length (∼1.3  cm), permanent magnet electron lens is used to image micron-size features (of a metal…”
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Observation of a THz-sub-THz spontaneous coherent undulator radiation driven by a low energy electron beam from a thermionic RF electron gun by Smirnov, A.V., Agustsson, R., Berg, W.J., Dooling, J., Campese, T., Chen, Y., Gavryushkin, D., Erwin, L., Hartzell, J., Keane, R., O’Shea, F.H., Spranza, E., Pasky, S., Ruelas, M., Sun, Y., Zholents, A.A.

“…We report observations of an intense, multi-band, sub-THz and THz radiation extracted from a ∼2-3 MeV electron beam with a flat transverse profile propagating…”
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Policy gradient methods for free-electron laser and terahertz source optimization and stabilization at the FERMI free-electron laser at Elettra by O’Shea, F. H., Bruchon, N., Gaio, G.

“…In this article we report on the application of a model-free reinforcement learning method to the optimization of accelerator systems. We simplify a policy…”
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Observation of a variable sub-THz radiation driven by a low energy electron beam from a thermionic rf electron gun by Smirnov, A. V., Agustsson, R., Berg, W. J., Boucher, S., Dooling, J., Campese, T., Chen, Y., Erwin, L., Jacobson, B., Hartzell, J., Lindberg, R., Murokh, A., O’Shea, F. H., Spranza, E., Pasky, S., Ruelas, M., Sereno, N. S., Sun, Y., Zholents, A. A.

“…We report observations of an intense sub-THz radiation extracted from a ~3 MeV electron beam with a flat transverse profile propagating between two parallel…”
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Short period, high field cryogenic undulator for extreme performance x-ray free electron lasers by O’Shea, F. H., Marcus, G., Rosenzweig, J. B., Scheer, M., Bahrdt, J., Weingartner, R., Gaupp, A., Grüner, F.

“…Short period, high field undulators can enable short wavelength free electron lasers (FELs) at low beam energy, with decreased gain length, thus allowing much…”
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Harmonic radiation of a relativistic nonlinear inverse Compton scattering using two laser wavelengths by Sakai, Y., Williams, O., Andonian, G., Fukasawa, A., Hemsing, E., Marinelli, A., Barber, S., O’Shea, F. H., Rosenzweig, J. B.

“…The use of two different wavelength lasers in the nonlinear regime of the inverse Compton scattering interaction is proposed in order to provide a new strategy…”
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Single shot diffraction of picosecond 8.7-keV x-ray pulses by O’Shea, F. H., Williams, O., Andonian, G., Barber, S., Sakai, Y., Rosenzweig, J. B., Pogorelsky, I., Fedurin, M., Kusche, K., Yakimenko, V.

“…We demonstrate multiphoton, single shot diffraction images of x rays produced by inverse Compton scattering a high-power CO_{2} laser from a relativistic…”
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Tokamak edge localized mode onset prediction with deep neural network and pedestal turbulence by Joung, Semin, Smith, David R., McKee, G., Yan, Z., Gill, K., Zimmerman, J., Geiger, B., Coffee, R., O’Shea, F.H., Jalalvand, A., Kolemen, E.

“…Abstract A neural network, BES-ELMnet, predicting a quasi-periodic disruptive eruption of the plasma energy and particles known as edge localized mode (ELM)…”
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Demonstration of single-shot picosecond time-resolved MeV electron imaging using a compact permanent magnet quadrupole based lens by Cesar, D, Maxson, J, Musumeci, P, Sun, Y, Harrison, J, Frigola, P, O'Shea, F. H, To, H, Alesini, D, Li, R. K

“…Phys. Rev. Lett. 117, 024801 (2016) We present the results of an experiment where a short focal length (~ 1.3 cm) permanent magnet electron lens is used to…”
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Tokamak edge localized mode onset prediction with deep neural network and pedestal turbulence by Joung, Semin, Smith, David R., McKee, G., Yan, Z., Gill, K., Zimmerman, J., Geiger, B., Coffee, R., O’Shea, F. H., Jalalvand, A., Kolemen, E.

“…A neural network, BES-ELMnet, predicting a quasi-periodic disruptive eruption of the plasma energy and particles known as edge localized mode (ELM) onset is…”
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Observation of a THz-sub-THz spontaneous coherent undulator radiation driven by a low energy electron beam from a thermionic RF electron gun by Smirnov, A. V., Agustsson, R., Berg, W. J., Dooling, J., Campese, T., Chen, Y., Gavryushkin, D., Erwin, L., Hartzell, J., Keane, R., O’Shea, F. H., Spranza, E., Pasky, S., Ruelas, M., Sun, Y., Zholents, A. A.

“…In this work, we report observations of an intense, multi-band, sub-THz and THz radiation extracted from a similar to 2-3 MeV electron beam with a flat…”
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Single shot diffraction of picosecond 8.7-keV x-ray pulses by O’Shea, F. H., Williams, O., Andonian, G., Barber, S., Sakai, Y., Rosenzweig, J. B., Pogorelsky, I., Fedurin, M., Kusche, K., Yakimenko, V.

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