Search Results - "O'Shea, P. G."

Harmonic generation in a terawatt x-ray free-electron laser by Freund, H P, O’Shea, P G

“…Abstract Terawatt x-ray free-electron lasers (XFELs) represent the frontier in further development of x-ray sources and require high current densities with…”
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Observation of the anomalous increase of the longitudinal energy spread in a space-charge-dominated electron beam by ZOU, Y, CUI, Y, REISER, M, O'SHEA, P. G

“…We report a new experimental study of the growth of longitudinal energy spread in a space-charge-dominated electron beam, with a beam energy of several keV and…”
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Nonlinear harmonic generation in free-electron lasers with helical wigglers by FREUND, H. P, O'SHEA, P. G, BIEDRON, S. G

“…It is widely believed that harmonics are suppressed in helical wigglers. However, linear harmonic generation (LHG) occurs by an azimuthal resonance that…”
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Experimental observations of soliton wave trains in electron beams by Mo, Y C, Kishek, R A, Feldman, D, Haber, I, Beaudoin, B, O'Shea, P G, Thangaraj, J C T

“…The first experimental observation of a Korteweg-de Vries-type soliton wave train in intense electron beams is reported. A narrow, large-amplitude perturbation…”
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Experimental observations of longitudinal space-charge waves in intense electron beams by Tian, K., Zou, Y., Cui, Y., Haber, I., Kishek, R. A., Reiser, M., O’Shea, P. G.

“…Studies of the dynamics of longitudinal space-charge waves in space-charge dominated beams propagating through a transport channel with a long solenoid are…”
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Gamma-Ray Production in a Storage Ring Free-Electron Laser by Litvinenko, V. N., Burnham, B., Emamian, M., Hower, N., Madey, J. M. J., Morcombe, P., O'Shea, P. G., Park, S. H., Sachtschale, R., Straub, K. D., Swift, G., Wang, P., Wu, Y., Canon, R. S., Howell, C. R., Roberson, N. R., Schreiber, E. C., Spraker, M., Tornow, W., Weller, H. R., Pinayev, I. V., Gavrilov, N. G., Fedotov, M. G., Kulipanov, G. N., Kurkin, G. Y., Mikhailov, S. F., Popik, V. M., Skrinsky, A. N., Vinokurov, N. A., Norum, B. E., Lumpkin, A., Yang, B.

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Free-Electron Lasers: Status and Applications by O'Shea, Patrick G., Freund, Henry P.

“…A free-electron laser consists of an electron beam propagating through a periodic magnetic field. Today such lasers are used for research in materials science,…”
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Longitudinal space-charge effects in a retarding field energy analyzer by Zou, Y., Cui, Y., Haber, I., Reiser, M., O’Shea, P. G.

“…Theoretical and experimental work has been carried out to study the longitudinal space-charge effects in a retarding field energy analyzer. A one-dimensional,…”
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Edge imaging in intense beams by Bernal, S., Quinn, B., Reiser, M., O'Shea, P. G.

“…The appearance of rings of charge observed near the edge of beams from high-perveance guns is described with a simple ray tracing technique inspired by the…”
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Compact high-resolution retarding field energy analyzer for space-charge-dominated electron beams by Zou, Y., Cui, Y., Yun, V., Valfells, A., Kishek, R. A., Bernal, S., Haber, I., Reiser, M., O'Shea, P. G., Wang, J. G.

“…We have developed a compact high-resolution retarding field energy analyzer for measuring the energy spread of space-charge-dominated electron beams. This…”
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The University of Maryland Electron Ring Program by Kishek, R.A., Beaudoin, B.L., Bernal, S., Cornacchia, M., Feldman, D., Fiorito, R., Haber, I., Koeth, T., Mo, Y.C., O'Shea, P.G., Rezaei, K. Poor, Sutter, D., Zhang, H.D.

“…The University of Maryland Electron Ring (UMER) is a unique machine that uses scaled electron beams at nonrelativistic energies (10keV) to inexpensively model…”
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Measurement of beam energy spread in a space-charge dominated electron beam by Cui, Y., Zou, Y., Reiser, M., Kishek, R. A., Haber, I., Bernal, S., O’Shea, P. G.

“…Characterization of beam energy spread in a space-charge dominated beam is very important to understanding the physics of intense beams. It is believed that…”
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Electron emission contributions to dark current and its relation to microscopic field enhancement and heating in accelerator structures by Jensen, Kevin L., Lau, Y. Y., Feldman, D. W., O’Shea, P. G.

“…Analytically tractable models of thermal-field emission, field enhancement, and heating mechanisms (Nottingham and resistive) are developed and combined to…”
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Radio frequency photoinjector using LaB6 cathode and a nitrogen drive laser by O’Shea, P. G., Lancaster, J. A., Sachtschale, R., Jones, C. R.

“…We report the successful operation of an inexpensive, simple, and reliable 2.856 GHz radio frequency photoinjector using a rugged LaB6 cathode and a nitrogen…”
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Design and field measurements of printed-circuit quadrupoles and dipoles by Zhang, W. W., Bernal, S., Li, H., Godlove, T., Kishek, R. A., O'Shea, P. G., Reiser, M., Yun, V., Venturini, M.

“…Air-core printed-circuit (PC) quadrupoles and dipoles have been developed for the University of Maryland electron ring, currently under construction. The…”
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Emittance of a photocathode: Effects of temperature and field by Jensen, Kevin L., O’Shea, P. G., Feldman, D. W.

“…The emittance of a photocathode is evaluated using a distribution function (“Moments”) approach to calculate the moments of the momentum. The effects of…”
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Smooth approximation model of dispersion with strong space charge for continuous beams by Bernal, S., Beaudoin, B., Koeth, T., O’Shea, P. G.

“…We apply the Venturini-Reiser (V-R) envelope-dispersion equations [M. Venturini and M. Reiser, Phys. Rev. Lett. 81, 96…”
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Ultraviolet free-electron laser driven by a high-brightness 45-MeV electron beam by O'SHEA, P. G, BENDER, S. C, ZAUGG, T. J, BYRD, D. A, EARLY, J. W, FELDMAN, D. W, FORTGANG, C. M, GOLDSTEIN, J. C, NEWNAM, B. E, SHEFFIELD, R. L, WARREN, R. W

“…We report on experimental studies of an ultraviolet (UV) free-electron laser (FEL) oscillator driven by low-energy electrons from a radio-frequency linear…”
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Tomography as a diagnostic tool for phase space mapping of intense particle beams by Stratakis, D., Kishek, R. A., Li, H., Bernal, S., Walter, M., Quinn, B., Reiser, M., O’Shea, P. G.

“…A technique is described for the tomographic mapping of transverse phase space in beams with space charge. Most prior studies where performed at high energy…”
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Experimental study of large-amplitude perturbations in space-charge dominated beams by Tian, K., Kishek, R. A., Haber, I., Reiser, M., O’Shea, P. G.

“…Detailed experimental measurements are presented concerning the propagation of space-charge waves of varying amplitudes in an intense, charged-particle beam. A…”
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