Search Results - "Feldman, D. W."

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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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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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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Experimental results from the Los Alamos FEL photoinjector by Feldman, D.W., Bender, S.C., Carlsten, B.E., Early, J., Feldman, R.B., Johnson, W.J.D., Lumpkin, A.H., O'Shea, P.G., Stein, W.E., Sheffield, R.L., Young, L.M.

“…The authors report some initial measurements of electron beam properties from the new photoinjector installed as the front end on the Los Alamos free-electron…”
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Design and analysis of experimental performance of the Los Alamos HIBAF facility accelerator using the INEX computer model by Carlsten, B.E., Young, L.M., Jones, M.E., Thode, L.E., Lumpkin, A.H., Feldman, D.W., Feldman, R.B., Blind, B., Browman, M.J., O'Shea, P.G.

“…The authors review the accelerator design of the high brightness accelerator free electron laser (FEL) (HIBAF) at Los Alamos National laboratory and analyze…”
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Advanced photocathode simulation and theory by Jensen, K.L., Feldman, D.W., O’Shea, P.G.

“…A low work function dispenser type photocathode that is self-annealing or repairing would have a substantial impact on Free Electron Lasers (FELs). On such a…”
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Raman Scattering by Local Modes in Germanium-Rich Silicon-Germanium Alloys by Feldman, D. W., Ashkin, M., Parker, James H.

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Theoretical model of the intrinsic emittance of a photocathode by Jensen, Kevin L., O'Shea, P. G., Feldman, D. W., Moody, N. A.

“…A theoretical expression for the intrinsic emittance of a photocathode is developed based on a method of evaluating moments of the emission distribution…”
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Raman Scattering by Optical Modes of Metals by Feldman, D. W., Parker, James H., Ashkin, M.

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Kinetic processes in continuously pulsed copper halide lasers by Liu, C., Feldman, D., Pack, J., Weaver, L.

“…Absorption measurements in the afterglow of electrically excited copper halide laser mixtures are described. Ground state and metastable copper density decay…”
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Prototype dispenser photocathode: Demonstration and comparison to theory by Moody, N. A., Jensen, K. L., Feldman, D. W., O’Shea, P. G., Montgomery, E. J.

“…A method to significantly extend the operational lifetime of alkali-based photocathodes by diffusing cesium to the surface at moderate temperature is presented…”
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6.5: Electron emission from alkali-coated metal photocathodes by Montgomery, Eric J, Feldman, D W, O'Shea, P G, Pan, P Z, Sennett, N, Jensen, K L

“…Quantum efficiency (QE) of a photoemissive surface is lowered via a sub-monolayer coating of adsorbed alkali metal: we here measure QE of cesium, potassium,…”
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Prototype dispenser photocathode: Demonstration and comparisonto theory by Moody, N. A., Jensen, K. L., Feldman, D. W., O'Shea, P. G., Montgomery, E. J.

“…A method to significantly extend the operational lifetime of alkali-based photocathodes by diffusing cesium to the surface at moderate temperature is presented…”
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Helium abundance variations in the solar wind by Borrini, G., Gosling, J. T., Bame, S. J., Feldman, W. D.

“…Helium abundance variations in the solar wind have been studied by using data obtained with Los Alamos plasma instrumentation on IMP-6, -7, and -8 from 1971…”
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Recent results from the Los Alamos free-electron laser by Feldman, D., Warren, R., Carlsten, B., Stein, W., Lumpkin, A., Bender, S., Spalek, G., Watson, J., Young, L., Fraser, J., Goldstein, J., Takeda, H., Wang, T., Chan, K., McVey, B., Newnam, B., Lohsen, R., Feldman, R., Copper, R., Johnson, W., Brau, C.

“…In this paper, we review the most recent experimental results of the Los Alamos free-electron laser program. Three major efforts will be described: lasing at…”
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The quantum efficiency of dispenser photocathodes: Comparison of theory to experiment by Jensen, Kevin L., Feldman, Donald W., O’Shea, Patrick G.

“…The quantum efficiency (QE) characteristics of commercially available dispenser cathodes were measured, giving QEs of (for Scandate) 6.5×10−5, 2.0×10−4, and…”
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Generalized electron emission model for field, thermal, and photoemission by Jensen, Kevin L., O’Shea, Patrick G., Feldman, Donald W.

“…Analysis of electron emission from photocathodes, field emitters under extreme fields, or thermionic emitters operated at reduced temperature, utilize…”
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Fabrication and measurement of efficient, robust cesiated dispenser photocathodes by Montgomery, E.J., Feldman, D.W., O'Shea, P.G., Pan, Z., Moody, N.A., Jensen, K.L.

“…Photocathodes for high power free electron lasers face significant engineering and physics challenges in the quest for efficient, robust, long-lived, prompt…”
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Prior opportunities to identify abuse in children with abusive head trauma by Letson, Megan M., MD, MEd, Cooper, Jennifer N., PhD, Deans, Katherine J., MD, Scribano, Philip V., DO, MSCE, Makoroff, Kathi L., MD, MEd, Feldman, Kenneth W., MD, Berger, Rachel P., MD, MPH

“…Abstract Infants with minor abusive injuries are at risk for more serious abusive injury, including abusive head trauma (AHT). Our study objective was to…”
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A theoretical photocathode emittance model including temperature and field effects by Jensen, K.L., Feldman, D.W., Montgomery, E.J., O'Shea, P.G., Moody, N.A., Petillo, J.

“…A recently developed model of emittance & brightness of photocathode based on "moments" of the electron emission distribution is extended here to non-zero…”
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