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Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Tomographic Imaging Of Nonsymmetric Multicomponent Tailored Supersonic Flows From Structured Gas Nozzles, Grigory V. Golovin, Sudeep Banerjee, J Zhang, Shouyuan Chen, Cheng Liu, Baozhen Zhao, J Mills, Kevin J. Brown, C Petersen, Donald P. Umstadter
Tomographic Imaging Of Nonsymmetric Multicomponent Tailored Supersonic Flows From Structured Gas Nozzles, Grigory V. Golovin, Sudeep Banerjee, J Zhang, Shouyuan Chen, Cheng Liu, Baozhen Zhao, J Mills, Kevin J. Brown, C Petersen, Donald P. Umstadter
Donald Umstadter Publications
We report experimental results on the production and characterization of asymmetric and composite supersonic gas flows, created by merging independently controllable flows from multiple nozzles. We demonstrate that the spatial profiles are adjustable over a large range of parameters, including gas density, density gradient, and atomic composition. The profiles were precisely characterized using three-dimensional tomography. The creation and measurement of complex gas flows is relevant to numerous applications, ranging from laser-produced plasmas to rocket thrusters.
Compact Source Of Narrowband And Tunable X-Rays For Radiography, Sudeep Banerjee, Shouyuan Chen, Nathan D. Powers, Daniel Haden, Cheng Liu, Grigory V. Golovin, Jun Zhang, Baozhen Zhao, S. Clarke, Sara Pozzi, Jack Silano, H. Karwowski, Donald Umstadter
Compact Source Of Narrowband And Tunable X-Rays For Radiography, Sudeep Banerjee, Shouyuan Chen, Nathan D. Powers, Daniel Haden, Cheng Liu, Grigory V. Golovin, Jun Zhang, Baozhen Zhao, S. Clarke, Sara Pozzi, Jack Silano, H. Karwowski, Donald Umstadter
Donald Umstadter Publications
We discuss the development of a compact X-ray source based on inverse-Compton scattering with a laser-driven electron beam. This source produces a beam of high-energy X-rays in a narrow cone angle (5–10 mrad), at a rate of 108 photons-s_1. Tunable operation of the source over a large energy range, with energy spread of ~50%, has also been demonstrated. Photon energies >10 MeV have been obtained. The narrowband nature of the source is advantageous for radiography with low dose, low noise, and minimal shielding.
All-Laser-Driven Thomson X-Ray Sources, Donald Umstadter
All-Laser-Driven Thomson X-Ray Sources, Donald Umstadter
Donald Umstadter Publications
We discuss the development of a new generation of accelerator-based hard X-ray sources driven exclusively by laser light. High-intensity laser pulses serve the dual roles: first, accelerating electrons by laser-driven plasma wakefields, and second, generating X-rays by inverse Compton scattering. Such all-laser-driven X-rays have recently been demonstrated to be energetic, tunable, relatively narrow in bandwidth, short pulsed and well collimated. Such characteristics, especially from a compact source, are highly advantageous for numerous advanced X-ray applications—in metrology, biomedicine, materials, ultrafast phenomena, radiology and fundamental physics.
Tunable Monoenergetic Electron Beams From Independently Controllable Laser-Wakefield Acceleration And Injection, Grigory V. Golovin, Shouyuan Chen, Nathan D. Powers, Cheng Liu, Sudeep Banerjee, J Zhang, M Zeng, Z Sheng, Donald P. Umstadter
Tunable Monoenergetic Electron Beams From Independently Controllable Laser-Wakefield Acceleration And Injection, Grigory V. Golovin, Shouyuan Chen, Nathan D. Powers, Cheng Liu, Sudeep Banerjee, J Zhang, M Zeng, Z Sheng, Donald P. Umstadter
Donald Umstadter Publications
We report the results of experiments on laser-wakefield acceleration in a novel two-stage gas target with independently adjustable density and atomic-composition profiles.We were able to tailor these profiles in a way that led to the separation of the processes of electron injection and acceleration and permitted independent control of both. This resulted in the generation of stable, quasimonoenergetic electron beams with central energy tunable in 50–300 MeV range. For the first time, we are able to independently control the beam charge and energy spread over the entire tunability range.