Quantitative X-ray phase-contrast microtomography from a compact laser-driven betatron source

Abstract

X-ray phase-contrast imaging has recently led to a revolution in resolving power and tissue contrast in biomedical imaging, microscopy and materials science. The necessary high spatial coherence is currently provided by either large-scale synchrotron facilities with limited beamtime access or by microfocus X-ray tubes with rather limited flux. X-rays radiated by relativistic electrons driven by well-controlled high-power lasers offer a promising route to a proliferation of this powerful imaging technology. A laser-driven plasma wave accelerates and wiggles electrons, giving rise to a brilliant keV X-ray emission. This so-called betatron radiation is emitted in a collimated beam with excellent spatial coherence and remarkable spectral stability. Here we present a phase-contrast microtomogram of a biological sample using betatron X-rays. Comprehensive source characterization enables the reconstruction of absolute electron densities. Our results suggest that laser-based X-ray technology offers the potential for filling the large performance gap between synchrotron- and current X-ray tube-based sources.

Observation of Betatron X-Ray Radiation in a Self-Modulated Laser Wakefield Accelerator Driven with Picosecond Laser Pulses

“…A source based on betatron emission from a laserplasma accelerator [1] is attractive for this purpose because it generates a small-divergence , broadband x-ray beam that can be used to backlight the target being studied. Betatron x-ray radiation has been used for biological and medical purposes, such as x-ray phase contrast imaging of insects [2][3][4] and hard x-ray radiography of bone [5]. Its unique properties also make it suitable for studying the dynamics of high-energy-density plasmas and warm dense matter, a state near solid densities,…”

High-resolution short-exposure small-animal laboratory x-ray phase-contrast tomography

“…Still, the microfocus source of this system lacks sufficient brightness and spot size to allow high-spatial-resolution imaging with reasonable scan times. Several laser-/accelerator-based “compact” systems have been proposed as alternative high-brightness laboratory sources121314. One of these, the inverse-Compton scattering Compact Light Source (CLS), has achieved sufficient stability for high-quality tomographic imaging, both in absorption, where sub-100 μm bone imaging has been demonstrated with approx.…”

Non-destructive phase contrast hard x-ray imaging to reveal the three-dimensional microstructure of soft and hard tissues

“…Phase contrast imaging is often successfully performed via synchrotron radiation-based micro-computed tomography (SRµCT); however, experiments at synchrotron facilities are sophisticated and impose severe time restrictions on the user. 7 Nowadays, X-ray laboratory-based µCT systems are used widely in scientific research. However, the potential and flexibility of these systems are underestimated.…”