A5004483848- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Atomic and Molecular Physics
- High-pressure geophysics and materials
- Advanced X-ray Imaging Techniques
- Laser Design and Applications
- Advanced Chemical Physics Studies
- Laser-Matter Interactions and Applications
- Ion-surface interactions and analysis
- Chemical Thermodynamics and Molecular Structure
- Radiation Dose and Imaging
- Astronomy and Astrophysical Research
- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Medical Image Segmentation Techniques
- Stellar, planetary, and galactic studies
- Radiology practices and education
- Laser Material Processing Techniques
- Magnetic confinement fusion research
- Geophysics and Gravity Measurements
- Particle Detector Development and Performance
- Advanced Mathematical Theories and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- History of Medical Practice
- Adaptive optics and wavefront sensing
Imperial College London
2009-2024
Florence (Netherlands)
2019
Queen's University Belfast
2019
Cambridge University Press
1980
New York University Press
1980
Betatron radiation from laser wakefield accelerators is an ultrashort pulsed source of hard, synchrotron-like x-ray radiation. It emanates a centimetre scale plasma accelerator producing GeV level electron beams. In recent years betatron has been developed as unique capable high resolution images in compact geometries. However, until now, the short pulse nature this not exploited. This report details first experiment to utilize image rapidly evolving phenomenon by using it radiograph driven...
We investigate the mechanism by which relativistic electron bunches created at surface of a target irradiated very short and intense laser pulse transfer energy to deeper parts target. In existing theories, dominant heating is that resistive neutralizing return current. addition this, we find large amplitude plasma waves are induced in wake bunches. The subsequent collisional damping these represents source can exceed rate. As result, solid targets heat significantly faster than has been...
We have utilized a newly developed high-resolution X-ray spectrometer to measure the shapes of spectral lines produced from laser-irradiated targets on Orion laser facility in United Kingdom. present measurements He-β spectra chlorine and chromium irradiated by either long-pulse or short-pulse beam. The experimental conditions provide spread plasma density ranging about 1019 1024 cm−3. calculations that show relative intensities Li-like satellite can be used infer lower range, especially if...
In this paper we report the experimental implementation of a theoretically proposed technique for creating photoionized plasma in laboratory using x-ray line radiation. Using Sn laser to irradiate an Ar gas target, photoionization parameter, ξ=4πF/N_{e}, reached values order 50ergcms^{-1}, where F is radiation flux ergcm^{-2}s^{-1}. The significance that allows us mimic effective spectral temperatures excess 1 keV. We show our starts be collisionally dominated before peak drive. However,...
The time-dependent collisional-radiative code ALICE [E. G. Hill and S. J. Rose, High Energy Density Phys. 5, 302 (2009)] is used to model the spectrum from a laboratory photoionized silicon plasma [S. Fujioka et al., Nat. 821 (2009)]. results show good agreement with lend support accompanying analytical discussion of spectra, their parametrization, relevance astrophysics.
X-ray emission spectroscopy has been used to study hot dense plasmas produced using high power laser irradiation of dot samples buried in low Z foils plastic or diamond. By combining a contrast short pulse (picosecond timescale) beam operating second harmonic with long (nanosecond beams third harmonic, and shaping the beams, range plasma temperatures from 400eV up 2.5keV electron densities 5e22 1e24/cc have accessed. Examples are given measurements effects such as ionization potential...
We describe laboratory experiments to generate x-ray photoionized plasmas of relevance accretion-powered sources such as neutron star binaries and quasars, with significant improvements over previous work. A key quantity is referenced, namely the photoionization parameter, defined ξ=4πF/ne where F flux ne electron density. This normally meaningful in an astrophysical steady-state context, but also commonly used literature a figure merit for that are, necessity, time-dependent. demonstrate...
We have used the Shenguang II laser in third harmonic (351 nm) to investigate emission of L-shell radiation 3.3 4.4 keV range generated using thin foils Sn coated onto a parylene substrate with irradiation order 10 15 Wcm -2 and nanosecond pulse duration.In our experiment, we concentrated on assessing non-laser irradiated side as this allows an experimental geometry relevant experiments photo-ionised plasmas where secondary target must be placed close source, achieve X-ray fluxes appropriate...
Thomson scattering is well used as a diagnostic in many areas of high energy density physics. In this paper, we quantitatively demonstrate the practicality using short-pulse laser-plasma experiments regime, where plasmas probed are at solid and have temperatures hundreds eV backlighter produced with an optical laser. This method allows diagnosis both spatially temporally temperature distributions interactions which independent from, would act useful complement to, existing spectroscopic methods.