title: Soft x-ray backlighting of cryogenic implosions using a narrowband crystal imaging system (invited).
abstract: A high-performance cryogenic DT inertial confinement fusion implosion experiment is an especially challenging backlighting configuration because of the high self-emission of the core at stagnation and the low opacity of the DT shell. High-energy petawatt lasers such as OMEGA EP promise significantly improved backlighting capabilities by generating high x-ray intensities and short emission times. A narrowband x-ray imager with an astigmatism-corrected bent quartz crystal for the Si Heα line at ∼1.86 keV was developed to record backlit images of cryogenic direct-drive implosions. A time-gated recording system minimized the self-emission of the imploding target. A fast target-insertion system capable of moving the backlighter target ∼7 cm in ∼100 ms was developed to avoid interference with the cryogenic shroud system. With backlighter laser energies of ∼1.25 kJ at a 10-ps pulse duration, the radiographic images show a high signal-to-background ratio of >100:1 and a spatial resolution of the order of 10 μm. The backlit images can be used to assess the symmetry of the implosions close to stagnation and the mix of ablator material into the dense shell.
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: C
authors.initials: C
authors.lastname: Stoeckl
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: M
authors.initials: M
authors.lastname: Bedzyk
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: G
authors.initials: G
authors.lastname: Brent
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: R
authors.initials: R
authors.lastname: Epstein
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: G
authors.initials: G
authors.lastname: Fiksel
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: D
authors.initials: D
authors.lastname: Guy
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: V N
authors.initials: VN
authors.lastname: Goncharov
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: S X
authors.initials: SX
authors.lastname: Hu
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: S
authors.initials: S
authors.lastname: Ingraham
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: D W
authors.initials: DW
authors.lastname: Jacobs-Perkins
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: R K
authors.initials: RK
authors.lastname: Jungquist
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: F J
authors.initials: FJ
authors.lastname: Marshall
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: C
authors.initials: C
authors.lastname: Mileham
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: P M
authors.initials: PM
authors.lastname: Nilson
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: T C
authors.initials: TC
authors.lastname: Sangster
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Shoup
authors.affiliation: Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
authors.forename: W
authors.initials: W
authors.lastname: Theobald