title: Revisiting Bragg's X-ray microscope: scatter based optical transient grating detection of pulsed ionising radiation.
abstract: Transient optical gratings for detecting ultrafast signals are routine for temporally resolved photochemical investigations. Many processes can contribute to the formation of such gratings; we indicate use of optically scattering centres that can be formed with highly variable latencies in different materials and devices using ionising radiation. Coherent light scattered by these centres can form the short-wavelength-to-optical-wavelength, incoherent-to-coherent basis of a Bragg X-ray microscope, with inherent scope for optical phasing. Depending on the dynamics of the medium chosen, the way is open to both ultrafast pulsed and integrating measurements. For experiments employing brief pulses, we discuss high-dynamic-range short-wavelength diffraction measurements with real-time optical reconstructions. Applications to optical real-time X-ray phase-retrieval are considered.
authors.affiliation: School of Physics, Monash University, Victoria 3800, Australia.
authors.forename: Wilfred K
authors.initials: WK
authors.lastname: Fullagar
authors.forename: David M
authors.initials: DM
authors.lastname: Paganin
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Hall
mesh_terms: D004577:Electron Probe Microanalysis / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008853:Microscopy / Q000379:methods*; D017785:Photons; D011839:Radiation, Ionizing; D013052:Spectrometry, X-Ray Emission / Q000379:methods; D014961:X-Ray Diffraction / Q000379:methods; D014965:X-Rays