title: Mitigation of hard x-ray background in backlit pinhole imagers.
abstract: Experiments were performed to mitigate the hard x-ray background commonly observed in backlit pinhole imagers. The material of the scaffold holding the primary backlighter foil was varied to reduce the laser-plasma instabilities responsible for hot electrons and resulting hard x-ray background. Radiographic measurements with image plates showed a factor of >25 decrease in x-rays between 30 and 67 keV when going from a plastic to Al or V scaffold. A potential design using V scaffold offers a signal-to-background ratio of 6:1, a factor of 2 greater than using the bare plastic scaffold.
authors.affiliation: Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109-2143, USA.
authors.forename: J R
authors.initials: JR
authors.lastname: Fein
authors.affiliation: Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2143, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Keiter
authors.affiliation: Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109-2143, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Holloway
authors.affiliation: Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2143, USA.
authors.forename: S R
authors.initials: SR
authors.lastname: Klein
authors.affiliation: Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2143, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Davis
authors.affiliation: Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2143, USA.
authors.forename: R P
authors.initials: RP
authors.lastname: Drake