Publications by Year: 2020

2020
Ostermayr TM, Kreuzer C, Englbrecht FS, Gebhard J, Hartmann J, Huebl A, Haffa D, Hilz P, Parodi K, Wenz J, et al. Laser-driven x-ray and proton micro-source and application to simultaneous single-shot bi-modal radiographic imaging. [Internet]. 11 (1) :6174. Publisher's VersionAbstract
Radiographic imaging with x-rays and protons is an omnipresent tool in basic research and applications in industry, material science and medical diagnostics. The information contained in both modalities can often be valuable in principle, but difficult to access simultaneously. Laser-driven solid-density plasma-sources deliver both kinds of radiation, but mostly single modalities have been explored for applications. Their potential for bi-modal radiographic imaging has never been fully realized, due to problems in generating appropriate sources and separating image modalities. Here, we report on the generation of proton and x-ray micro-sources in laser-plasma interactions of the focused Texas Petawatt laser with solid-density, micrometer-sized tungsten needles. We apply them for bi-modal radiographic imaging of biological and technological objects in a single laser shot. Thereby, advantages of laser-driven sources could be enriched beyond their small footprint by embracing their additional unique properties, including the spectral bandwidth, small source size and multi-mode emission.
Roycroft R, Bowers B, Smith H, McCary E, Aymond F, Dyer GM, Quevedo HJ, Bradley PA, Vold EL, Yin L, et al. Streaked optical pyrometer for proton-driven isochoric heating experiments of solid and foam targets. AIP AdvancesAIP Advances [Internet]. 10 (4) :045220. Publisher's Version
Blakeney J, Quevedo H, Dyer GM, Ditmire T. Characterization of laser produced hot electron propagation via coherent transition radiation in cold and warm dense aluminum. Physics of PlasmasPhysics of Plasmas [Internet]. 27 (12) :123105. Publisher's Version
Roycroft R, Bradley PA, McCary E, Bowers B, Smith H, Dyer GM, Albright BJ, Blouin S, Hakel P, Quevedo HJ, et al. Experiments and simulations of isochorically heated warm dense carbon foam at the Texas Petawatt Laser. Matter and Radiation at ExtremesMatter and Radiation at Extremes [Internet]. 6 (1) :014403. Publisher's Version
Riley NJ, Quevedo HJ, Bengtson RD, Ditmire T, Kimmel M, Speas CS, Porter JL. Magnetic Field Effects on the Vishniac Overstability in Scaled Radiative Blast Waves. ASTROPHYSICAL JOURNAL. 895 (1).Abstract
We report experimental results on the stability of a magnetized laser-launched blast wave scaled to simulate a late-stage supernova remnant. We extend previous results to show the effect of a dynamically significant magnetic field on the spatial mode spectrum of the instability. We find that magnetic fields reduce instability growth, possibly influencing turbulent feedback to the interstellar medium.