A5065444610- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Laser-Matter Interactions and Applications
- High-pressure geophysics and materials
- Laser Design and Applications
- Advanced X-ray Imaging Techniques
- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Atomic and Molecular Physics
- Advanced Surface Polishing Techniques
- Particle Detector Development and Performance
- Ion-surface interactions and analysis
- Radiation Therapy and Dosimetry
- Pulsed Power Technology Applications
- Magnetic confinement fusion research
- Laser Material Processing Techniques
- Solid State Laser Technologies
- Advanced Radiotherapy Techniques
- Diamond and Carbon-based Materials Research
- Fusion materials and technologies
- Optical Systems and Laser Technology
- Dark Matter and Cosmic Phenomena
- Microstructure and mechanical properties
- Photocathodes and Microchannel Plates
- Ocular and Laser Science Research
Lund University
2013-2024
Getinge (Sweden)
2023
Skåne University Hospital
2023
CEA DAM Île-de-France
2018
Imperial College London
2017
John Adams Institute for Accelerator Science
2017
Czech Academy of Sciences, Institute of Physics
2017
Centre National de la Recherche Scientifique
2009-2013
Laboratoire d'Optique Appliquée
2010-2013
École Nationale Supérieure de Techniques Avancées
2009-2013
The generation of proton beams from ultrathin targets, down to 20nm in thickness, driven with ultrahigh contrast laser pulses is explored. conversion efficiency energy into protons increases as the foil thickness decreased, good beam quality and high efficiencies 1% being achieved, for kinetic exceeding 0.9MeV, 100nm thick aluminum foils at intensities 1019W∕cm2 33fs, 0.3J pulses. To minimize amplified spontaneous emission (ASE) induced effects disrupting acceleration mechanism, exceptional...
This article reports on an experimental method to fully reconstruct laser-accelerated proton beam parameters called radiochromic film imaging spectroscopy (RIS). RIS allows for the characterization of beams concerning real and virtual source size, envelope- microdivergence, normalized transverse emittance, phase space, spectrum. technique requires particular targets a high resolution detector. Therefore thin gold foils with microgrooved rear side were manufactured characterized. Calibrated...
The injection of quasimonoenergetic electron beams into a laser wakefield accelerator is demonstrated experimentally using density gradients at the edges plasma channel. In experiment, two pulses are used; main pulse drives wakefield, while second countercrossing beam produces whose expansion creates channel with significant gradients. Local electrons in triggered by wave breaking ramp. localized spatially and leads to generation collimated narrow energy spread relativistic 100 MeV level,...
Guided transport of a relativistic electron beam in solid is achieved experimentally by exploiting the strong magnetic fields created at interface two metals different electrical resistivities. This substantial relevance to Fast Ignitor approach fusion energy production [M. Tabak, Phys. Plasmas 12, 057305 (2005)10.1063/1.1871246], since it allows deposition be spatially tailored-thus adding design flexibility and preventing inefficiencies due spreading. In experiment, optical transition...
Abstract The properties of beams high energy protons accelerated during ultraintense, picosecond laser-irradiation thin foil targets are investigated as a function preplasma expansion at the target front surface. Significant enhancement in maximum proton and laser-to-proton conversion efficiency is observed optimum density gradients, due to self-focusing incident laser pulse. For very long expansion, propagating pulse filament, resulting highly uniform beams, but with reduced flux energy.
Laser-wakefield accelerators (LWFAs) are high acceleration-gradient plasma-based particle capable of producing ultra-relativistic electron beams. Within the strong focusing fields wakefield, accelerated electrons undergo betatron oscillations, emitting a bright pulse X-rays with micrometer-scale source size that may be used for imaging applications. Non-destructive X-ray phase contrast and tomography heterogeneous materials can provide insight into their processing, structure, performance....
The spatial distribution of protons, accelerated by intense femtosecond laser pulses interacting with thin target foils under oblique irradiation are investigated. Under certain conditions, the proton beams directed away from normal. This deviation is towards forward direction, an angle that increases level and duration amplified spontaneous emission pedestal before main pulse. In addition, for a given pulse, this beam energy. observations discussed in terms different electron acceleration...
An experimental investigation of lateral electron transport in thin metallic foil targets irradiated by ultraintense (>or=10(19) W/cm2) laser pulses is reported. Two-dimensional spatially resolved ion emission measurements are used to quantify electric-field generation resulting from transport. The measurement large electric fields ( approximately 0.1 TV/m) millimeters the focus reveals that energy continues long after pulse has decayed. Numerical simulations confirm a very strong...
Technology based on high-peak-power lasers has the potential to provide compact and intense radiation sources for a wide range of innovative applications. In particular, electrons that are accelerated in wakefield an laser pulse oscillate around propagation axis emit X-rays. This betatron source, which essentially reproduces principle synchrotron at millimeter scale, provides bright with femtosecond duration high spatial coherence. However, despite its unique features, usability source been...
Research efforts in FLASH radiotherapy have increased at an accelerated pace recently. involves ultra-high dose rates and has shown to reduce toxicity normal tissue while maintaining tumor response pre-clinical studies when compared conventional rate radiotherapy. The goal of this review is summarize the performed to-date with proton, electron, heavy ion radiotherapy, particular emphasis on physical aspects each study advantages disadvantages modality. Beam delivery parameters, experimental...
We report on a study controlled injection of electrons into the accelerating phase plasma wakefield accelerator by tailoring target density distribution using two independent sources gas. The tailored is achieved experimentally inserting narrow nozzle, with an orifice diameter only $400\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$, jet gas supplied from 2 mm nozzle. combination these nozzles used to create regions different connected gradient. Using this setup we show control charge and energy...
An electron beam of very high energy (50-250 MeV) can potentially produce a more favourable radiotherapy dose distribution compared to state-of-the-art photon based technique. To an sufficiently allow for long penetration depth (several cm), large accelerating structures are needed when using conventional radio-frequency technology, which may not be possible due economical or spatial constraints. In this paper, we show transport and focusing laser wakefield accelerated beams with maximum 160...
Proton acceleration from the interaction of ultra-short laser pulses with thin foil targets at intensities greater than 10(18) W cm(-2) is discussed. An overview physical processes giving rise to generation protons multi-MeV energies, in well defined beams excellent spatial quality, presented. Specifically, discussion centres on influence pulse contrast and energy distributions accelerated proton beams. Results an ongoing experimental investigation using 10 Hz multi-terawatt Ti:sapphire (35f...
The influence of shock waves, driven by amplified spontaneous emission (ASE), on laser-accelerated proton beams is investigated. A local deformation, produced a cold wave launched the ablation pressure ASE pedestal, can under oblique laser irradiation significantly direct beam toward axis. This be understood in frame target normal sheath acceleration as from an area where shifted Hydrodynamic simulations and experimental data show that there exists window parameter space deformed yet...
Low-intensity laser prepulses (<1013 W cm−2, nanosecond duration) are a major issue in experiments on laser-induced generation of protons, often limiting the performances proton sources produced by high-intensity lasers (≈1019 picosecond or femtosecond duration). Depending intensity regime, several effects may be associated with prepulse, some which discussed this paper: (i) destruction thin foil targets shock generated prepulse; (ii) creation preplasma target front side affecting...
The x-ray emission in laser-plasma accelerators can be a powerful tool to understand the physics of relativistic interaction. It is shown here that mapping betatron radiation obtained from beam profile when an aperture mask positioned just beyond end region. influence plasma density on position and longitudinal investigated compared particle-in-cell simulations. measurement length provides insight dynamics interaction, including electron self-injection region, possible multiple injection,...
In this work, planar two-photon laser-induced fluorescence (2p-LIF) is applied for the first time to analyze fluid dependent spray structure and atomization behavior of water ethanol in a quantitative way. A commercial six-hole DISI (Direct-Injection Spark-Ignition) injector was studied at different injection pressures, operated with liquids containing LIF dye fluorescein. Specifically DISI-injectors, fluid-dependent very complex not fully understood due cavitating, turbulent nozzle flow...
Laser wakefield accelerators offer the possibility of compact electron acceleration. However one key outstanding issues with results reported to date is beam stability. Experiments on two laser systems reveal that contrast ratio between ASE pedestal and main pulse an important factor in determining quality beam. With a high (108) profile well collimated single having low pointing instability (<10 mrad rms). lower (106) contains multiple beamlets which exhibit large (≃50 A not only improves...
Spectral measurements of visible coherent transition radiation produced by a laser-plasma-accelerated electron beam are reported. The significant periodic modulations that observed in the spectrum result from interference multiple bunches electrons. A Fourier analysis spectral fringes reveals electrons injected and accelerated plasma wave periods, up to at least 10 periods behind laser pulse. bunch separation scales with wavelength when density is changed over wide range. An fringe...
One challenge in the development of laser wakefield accelerators is to demonstrate sufficient control and reproducibility parameters generated bunches accelerated electrons. Here we report on a numerical study, where that trapping using density down-ramps allows for tuning several electron bunch by varying properties down-ramp. We show length determined difference before after ramp. Furthermore, transverse emittance controlled steepness Finally, amount trapped charge depends both emphasize...
This document provides detailed information on the status of Advanced and Novel Accelerators techniques describes steps that need to be envisaged for their implementation in future accelerators, particular high energy physics applications. It complements overview prepared update European Strategy particle physics, a description field. The scientific priorities community are described each technique acceleration able achieve accelerating gradient GeV~range or above. ALEGRO working group...
We present experimental results of vacuum laser acceleration (VLA) electrons using radially polarized pulses interacting with a plasma mirror. Tightly focused have been proposed for electron because their strong longitudinal electric field, making them ideal VLA. However, limited until now injecting into the field has remained considerable challenge. Here, we demonstrate experimentally that mirror as an injector solves this problem and permits to inject at phase laser, resulting in along...
Experimental results, supported by precise modeling, demonstrate optimization of a plasma-based injector with intermediate laser pulse energy ($<1\text{ }\text{ }\mathrm{J}$), corresponding to normalized vector potential ${a}_{0}=2.15$, using ionization injection in tailored plasma density profile. An increase electron bunch quality and is achieved experimentally the extension downramp at exit. Optimization focal position profile shown efficiently reduce angular deviation, leading better...