Laser-driven x-ray and neutron source development for industrial applications of plasma accelerators. (26th November 2015)

• Record Type: Journal Article
• Authors: Brenner, C M; Mirfayzi, S R; Rusby, D R; Armstrong, C; Alejo, A; Wilson, L A; Clarke, R; Ahmed, H; Butler, N M H; Haddock, D; Higginson, A; McClymont, A; Murphy, C; Notley, M; Oliver, P; Allott, R; Hernandez-Gomez, C; Kar, S; McKenna, P; Neely, D
• Is Part Of: Plasma physics and controlled fusion. Volume 58:Number 1(2016:Jan.)
• Publication Date: 2015-11-26
• Subjects: laser -- acceleration -- plasma -- applications; Plasma (Ionized gases) -- Periodicals; Controlled fusion -- Periodicals; 530.44
• DOI: 10.1088/0741-3335/58/1/014039
• Languages: English
• ISSNs: 0741-3335

Abstract

Abstract: Pulsed beams of energetic x-rays and neutrons from intense laser interactions with solid foils are promising for applications where bright, small emission area sources, capable of multi-modal delivery are ideal. Possible end users of laser-driven multi-modal sources are those requiring advanced non-destructive inspection techniques in industry sectors of high value commerce such as aerospace, nuclear and advanced manufacturing. We report on experimental work that demonstrates multi-modal operation of high power laser-solid interactions for neutron and x-ray beam generation. Measurements and Monte Carlo radiation transport simulations show that neutron yield is increased by a factor ~2 when a 1 mm copper foil is placed behind a 2 mm lithium foil, compared to using a 2 cm block of lithium only. We explore x-ray generation with a 10 picosecond drive pulse in order to tailor the spectral content for radiography with medium density alloy metals. The impact of using >1 ps pulse duration on laser-accelerated electron beam generation and transport is discussed alongside the optimisation of subsequent bremsstrahlung emission in thin, high atomic number target foils. X-ray spectra are deconvolved from spectrometer measurements and simulation data generated using the GEANT4 Monte Carlo code. We also demonstrate the unique capability of laser-driven x-rays in being able to deliver single pulse high spatial resolution projection imaging of thick metallic objects. Active detector radiographic imaging of industrially relevant sample objects with a 10 ps drive pulse is presented for the first time, demonstrating that features of 200 μ m size are resolved when projected at high magnification.