Shielded radiography with a laser-driven MeV-energy X-ray source

Authors

Shouyuan Chen, University of Nebraska–LincolnFollow
Grigory V. Golovin, University of Nebraska-LincolnFollow
Cameron Miller, University of Michigan
Daniel Haden, University of Nebraska-Lincoln
Sudeep Banerjee, University of Nebraska–LincolnFollow
Ping Zhang, University of Nebraska–LincolnFollow
Cheng Liu, University of Nebraska–LincolnFollow
Jun Zhang, University of Nebraska–Lincoln
Baozhen Zhao, University of Nebraska–LincolnFollow
Shaun Clarke, University of Michigan
Sara Pozzi, University of Michigan
Donald Umstadter, University of Nebraska-LincolnFollow

Date of this Version

2016

Citation

Published in Nuclear Instruments and Methods in Physics Research B 366 (2016), pp. 217–223. doi 10.1016/j.nimb.2015.11.007

Comments

Copyright © 2015 Elsevier B.V. Used by permission.

Abstract

We report the results of experimental and numerical-simulation studies of shielded radiography using narrowband MeVenergy X-rays from a compact all-laser-driven inverse-Compton-scattering X-ray light source. This recently developed Xray light source is based on a laser-wakefield accelerator with ultra-high-field gradient (GeV/cm). We demonstrate experimentally high-quality radiographic imaging (image contrast of 0.4 and signal-to-noise ratio of 2:1) of a target composed of 8-mm thick depleted uranium shielded by 80-mm thick steel, using a 6-MeV X-ray beam with a spread of 45% (FWHM) and 107 photons in a single shot. The corresponding dose of the X-ray pulse measured in front of the target is ~100 nGy/ pulse. Simulations performed using the Monte-Carlo code MCNPX accurately reproduce the experimental results. These simulations also demonstrate that the narrow bandwidth of the Compton X-ray source operating at 6 and 9 MeV leads to a reduction of deposited dose as compared to broadband bremsstrahlung sources with the same end-point energy. The Xray beam’s inherently low-divergence angle (~mrad) is advantageous and effective for interrogation at standoff distance. These results demonstrate significant benefits of all-laser driven Compton X-rays for shielded radiography.