title: Advances in x-ray framing cameras at the National Ignition Facility to improve quantitative precision in x-ray imaging.
abstract: We describe an experimental method to measure the gate profile of an x-ray framing camera and to determine several important functional parameters: relative gain (between strips), relative gain droop (within each strip), gate propagation velocity, gate width, and actual inter-strip timing. Several of these parameters cannot be measured accurately by any other technique. This method is then used to document cross talk-induced gain variations and artifacts created by radiation that arrives before the framing camera is actively amplifying x-rays. Electromagnetic cross talk can cause relative gains to vary significantly as inter-strip timing is varied. This imposes a stringent requirement for gain calibration. If radiation arrives before a framing camera is triggered, it can cause an artifact that manifests as a high-intensity, spatially varying background signal. We have developed a device that can be added to the framing camera head to prevent these artifacts.
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: L R
authors.initials: LR
authors.lastname: Benedetti
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Holder
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: M
authors.initials: M
authors.lastname: Perkins
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: C G
authors.initials: CG
authors.lastname: Brown
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: C S
authors.initials: CS
authors.lastname: Anderson
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: F V
authors.initials: FV
authors.lastname: Allen
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: R B
authors.initials: RB
authors.lastname: Petre
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: D
authors.initials: D
authors.lastname: Hargrove
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Glenn
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: N
authors.initials: N
authors.lastname: Simanovskaia
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: D K
authors.initials: DK
authors.lastname: Bradley
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: P
authors.initials: P
authors.lastname: Bell