Download or read book Laser Wakefield Electron Acceleration written by Karl Schmid and published by Springer Science & Business Media. This book was released on 2011-05-18 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis covers the few-cycle laser-driven acceleration of electrons in a laser-generated plasma. This process, known as laser wakefield acceleration (LWFA), relies on strongly driven plasma waves for the generation of accelerating gradients in the vicinity of several 100 GV/m, a value four orders of magnitude larger than that attainable by conventional accelerators. This thesis demonstrates that laser pulses with an ultrashort duration of 8 fs and a peak power of 6 TW allow the production of electron energies up to 50 MeV via LWFA. The special properties of laser accelerated electron pulses, namely the ultrashort pulse duration, the high brilliance, and the high charge density, open up new possibilities in many applications of these electron beams.

Download or read book Beam Acceleration In Crystals And Nanostructures Proceedings Of The Workshop written by Gerard Mourou and published by . This book was released on 2020 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Laser Wakefield and Direct Acceleration in the Plasma Bubble Regime written by Zhang, Xi (Ph. D.) and published by . This book was released on 2017 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser wakefield acceleration (LWFA) and direct laser acceleration (DLA) are two different kinds of laser plasma electron acceleration mechanisms. LWFA relies on the laser-driven plasma wave to accelerate electrons. The interaction of ultra-short ultra-intensive laser pulses with underdense plasma leads the LWFA into a highly nonlinear regime (“plasma bubble regime”) that attracts particular interest nowadays. DLA accelerates electrons by laser electromagnetic wave in the ion channel or the plasma bubble through the Betatron resonance. This dissertation presents a hybrid laser plasma electron acceleration mechanism. We investigate its features through particle-in-cell (PIC) simulations and the single particle model. The hybrid laser plasma electron acceleration is the merging concept between the LWFA and the DLA, so called laser wakefield and direct acceleration (LWDA). The requirements of the initial conditions of the electron to undergo the LWDA are determined. The electron must have a large initial transverse energy. Two electron injection mechanisms that are suitable for the LWDA, density bump injection and ionization induced injection, are studied in detail. The features of electron beam phase space and electron dynamics are explored. Electron beam phase space appears several unique features such as spatially separated two groups, the correlation between the transverse energy and the relativistic factor and the double-peak spectrum. Electrons are synergistically accelerated by the wakefield as well as by the laser electromagnetic field in the laser-driven plasma bubble. LWDA are also investigated in the moderate power regime (10 TW) in regarding the effects of laser color and polarization. It is found that the frequency upshift laser pulse has better performance on avoiding time-jitter of electron energy spectra, electron final energy and electron charge yield. Some basic characters that related to the LWDA such as the effects of the subluminal laser wave, the effects of the longitudinal accelerating field, the electron beam emittance, the electron charge yield and potentially applications as radiation source are discussed.

Download or read book Laser Wakefield Electron Acceleration Over 100 MeV Driven by a Femtosecond Terawatt Laser Pulse written by M. Kando and published by . This book was released on 1997 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Laser Driven Sources of High Energy Particles and Radiation written by Leonida Antonio Gizzi and published by Springer Nature. This book was released on 2019-09-05 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents a selection of articles based on inspiring lectures held at the “Capri” Advanced Summer School, an original event conceived and promoted by Leonida Antonio Gizzi and Ralph Assmann that focuses on novel schemes for plasma-based particle acceleration and radiation sources, and which brings together researchers from the conventional accelerator community and from the high-intensity laser-matter interaction research fields. Training in these fields is highly relevant for ultra-intense lasers and applications, which have enjoyed dramatic growth following the development of major European infrastructures like the Extreme Light Infrastructure (ELI) and the EuPRAXIA project. The articles preserve the tutorial character of the lectures and reflect the latest advances in their respective fields. The volume is mainly intended for PhD students and young researchers getting started in this area, but also for scientists from other fields who are interested in the latest developments. The content will also appeal to radiobiologists and medical physicists, as it includes contributions on potential applications of laser-based particle accelerators.

Download or read book High Power Laser Plasma Interaction written by C. S. Liu and published by Cambridge University Press. This book was released on 2019-05-23 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of high-power laser-plasma interaction has grown in the last few decades, with applications ranging from laser-driven fusion and laser acceleration of charged particles to laser ablation of materials. This comprehensive text covers fundamental concepts including electromagnetics and electrostatic waves, parameter instabilities, laser driven fusion,charged particle acceleration and gamma rays. Two important techniques of laser proton interactions including target normal sheath acceleration (TNSA) and radiation pressure acceleration (RPA) are discussed in detail, along with their applications in the field of medicine. An analytical framework is developed for laser beat-wave and wakefield excitation of plasma waves and subsequent acceleration of electrons. The book covers parametric oscillator model and studies the coupling of laser light with collective modes.

Download or read book Challenges and Goals for Accelerators in the XXI Century written by Oliver Brning and published by World Scientific. This book was released on 2015 with total page 855 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The past 100 years of accelerator-based research have led the field from first insights into the structure of atoms to the development and confirmation of the Standard Model of physics. Accelerators have been a key tool in developing our understanding of the elementary particles and the forces that govern their interactions. This book describes the past 100 years of accelerator development with a special focus on the technological advancements in the field, the connection of the various accelerator projects to key developments and discoveries in the Standard Model, how accelerator technologies open the door to other applications in medicine and industry, and finally presents an outlook of future accelerator projects for the coming decades."--Provided by publisher.

Download or read book Laser Wakefield Acceleration and Relativistic Optical Guiding written by P. Sprangle and published by . This book was released on 1988 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: An electron acceleration method is investigated which employs a short (tau sub L about = 2 wp-1 about = 1 picosec), high power (P> or = 10 to the 15th power W), single frequency laser pulse to generate large amplitude (E> or = 17 (square of (omega/omega sub p) GW), relativistic optical during may be used to prevent the pulse from diffracting within the plasma. Keywords: Laser applications, Wakefield, Electron accelerator. (JHD).

Download or read book Short Pulse Laser Interactions With Matter An Introduction written by Paul Gibbon and published by World Scientific. This book was released on 2005-09-05 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book represents the first comprehensive treatment of the subject, covering the theoretical principles, present experimental status and important applications of short-pulse laser-matter interactions.Femtosecond lasers have undergone dramatic technological advances over the last fifteen years, generating a whole host of new research activities under the theme of “ultrafast science”. The focused light from these devices is so intense that ordinary matter is torn apart within a few laser cycles. This book takes a close-up look at the exotic physical phenomena which arise as a result of this new form of “light-matter” interaction, covering a diverse set of topics including multiphoton ionization, rapid heatwaves, fast particle generation and relativistic self-channeling. These processes are central to a number of exciting new applications in other fields, such as microholography, optical particle accelerators and photonuclear physics.Repository for numerical models described in Chapter 6 can be found at www.fz-juelich.de/zam/cams/plasma/SPLIM/./a

Download or read book Investigation of Electron Acceleration and Deceleration in Plasmas written by Shao-Wei Chou and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2016-05-24 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work covers several aspects related to Laser WakeField Acceleration (LWFA). A strong and ultrashort laser pulse can generate plasma waves with accelerating gradients up to 100s GV/m, four orders of magnitude higher than a conventional radio frequency linear accelerator. The LWFA electrons have been characterized as an ultra-short and high brilliance source. These remarkable properties lead to a compact accelerator which is of great scientific interest for building a table-top coherent free electron laser as well as a single-shot electron diffraction device. On the other hand, a new application of LWFA is to utilize the high peak current LWFA electron bunch to drive a wakefield efficiently inside a high density underdense plasma. The resulting wakefield quickly decelerates the driver bunch or accelerates a properly designed witness bunch, and therefore the plasma is utilized as a compact beam dump or an afterburner staged after a regular LWFA.

Download or read book Studies of Proton Driven Plasma Wakefield Acceleration written by Yangmei Li and published by Springer Nature. This book was released on 2020-07-15 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis focuses on a cutting-edge area of research, which is aligned with CERN's mainstream research, the "AWAKE" project, dedicated to proving the capability of accelerating particles to the energy frontier by the high energy proton beam. The author participated in this project and has advanced the plasma wakefield theory and modelling significantly, especially concerning future plasma acceleration based collider design. The thesis addresses electron beam acceleration to high energy whilst preserving its high quality driven by a single short proton bunch in hollow plasma. It also demonstrates stable deceleration of multiple proton bunches in a nonlinear regime with strong resonant wakefield excitation in hollow plasma, and generation of high energy and high quality electron or positron bunches. Further work includes the assessment of transverse instabilities induced by misaligned beams in hollow plasma and enhancement of the wakefield amplitude driven by a self-modulated long proton bunch with a tapered plasma. This work has major potential to impact the next generation of linear colliders and also in the long-term may help develop compact accelerators for use in industrial and medical facilities.

Download or read book Radiative Signatures of Electron Acceleration in a Fully Cavitated Laser Plasma Wakefield written by Michael Helle and published by . This book was released on 2010 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: A unique second harmonic radiation signature was first observed in this investigation, confirming the existence of the bubble regime. This second harmonic was generated by the interaction of the bubble's high-density electron sheath with a strong laser field. The bubble size, propagation distance, and the existence of multiple bubbles was obtained through careful characterization of this second harmonic signature. The observed strong correlation between the features of the second harmonic signature and the accelerated electrons provides a guidance to optimize the performance of Laser Wakefield Accelerators.

Download or read book Electron Acceleration in the Bubble Regime written by Oliver Jansen and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2014-05-27 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: The bubble regime of laser-wakefield acceleration has been studied over the recent years as an important alternative to classical accelerators. Several models and theories have been published, in particular a theory which provides scaling laws for acceleration parameters such as energy gain and acceleration length. This thesis deals with numerical simulations within the bubble regime, their comparison to these scaling laws and data obtained from experiments, as well as some specific phenomenona. With a comparison of the scaling laws with numerical results a parameter scan was able to show a large parameter space in which simulation and theory agree. An investigation of the limits of this parameter space revealed boundaries to other regimes. Comparing simulation data with data from experiments concerning laser pulse development and electron energies, it was found that experimental results can be adequately reproduced using the Virtual-Laser-Plasma-Laboratory code. In collaboration with the Institut fur Optik und Quantenelektronik at the Friedrich-Schiller University Jena synchrotron radiation emitted from the inside of the bubble was investigated.

Download or read book Proof of principle Experiments of Laser Wakefield Acceleration written by and published by . This book was released on 1994 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently there has been a great interest in laser-plasma accelerators as possible next-generation particle accelerators because of their potential for ultra high accelerating gradients and compact size compared with conventional accelerators. It is known that the laser pulse is capable of exciting a plasma wave propagating at a phase velocity close to the velocity of light by means of beating two-frequency lasers or an ultra short laser pulse. These schemes came to be known as the Beat Wave Accelerator (BWA) for beating lasers or as the Laser Wakefield Accelerator (LWFA) for a short pulse laser. In this paper, the principle of laser wakefield particle acceleration has been tested by the Nd:glass laser system providing a short pulse with a power of 10 TW and a duration of 1 ps. Electrons accelerated up to 18 MeV/c have been observed by injecting 1 MeV/c electrons emitted from a solid target by an intense laser impact. The accelerating field gradient of 30 GeV/m is inferred.

Download or read book Laser Wakefield Acceleration written by and published by . This book was released on 2014 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Particle accelerators enable scientists to study the fundamental structure of the universe, but have become the largest and most expensive of scientific instruments. In this project, we advanced the science and technology of laser-plasma accelerators, which are thousands of times smaller and less expensive than their conventional counterparts. In a laser-plasma accelerator, a powerful laser pulse exerts light pressure on an ionized gas, or plasma, thereby driving an electron density wave, which resembles the wake behind a boat. Electrostatic fields within this plasma wake reach tens of billions of volts per meter, fields far stronger than ordinary non-plasma matter (such as the matter that a conventional accelerator is made of) can withstand. Under the right conditions, stray electrons from the surrounding plasma become trapped within these "wake-fields", surf them, and acquire energy much faster than is possible in a conventional accelerator. Laser-plasma accelerators thus might herald a new generation of compact, low-cost accelerators for future particle physics, x-ray and medical research. In this project, we made two major advances in the science of laser-plasma accelerators. The first of these was to accelerate electrons beyond 1 gigaelectronvolt (1 GeV) for the first time. In experimental results reported in Nature Communications in 2013, about 1 billion electrons were captured from a tenuous plasma (about 1/100 of atmosphere density) and accelerated to 2 GeV within about one inch, while maintaining less than 5% energy spread, and spreading out less than 1/2 milliradian (i.e. 1/2 millimeter per meter of travel). Low energy spread and high beam collimation are important for applications of accelerators as coherent x-ray sources or particle colliders. This advance was made possible by exploiting unique properties of the Texas Petawatt Laser, a powerful laser at the University of Texas at Austin that produces pulses of 150 femtoseconds (1 femtosecond is 10-15 seconds) in duration and 150 Joules in energy (equivalent to the muzzle energy of a small pistol bullet). This duration was well matched to the natural electron density oscillation period of plasma of 1/100 atmospheric density, enabling efficient excitation of a plasma wake, while this energy was sufficient to drive a high-amplitude wake of the right shape to produce an energetic, collimated electron beam. Continuing research is aimed at increasing electron energy even further, increasing the number of electrons captured and accelerated, and developing applications of the compact, multi-GeV accelerator as a coherent, hard x-ray source for materials science, biomedical imaging and homeland security applications. The second major advance under this project was to develop new methods of visualizing the laser-driven plasma wake structures that underlie laser-plasma accelerators. Visualizing these structures is essential to understanding, optimizing and scaling laser-plasma accelerators. Yet prior to work under this project, computer simulations based on estimated initial conditions were the sole source of detailed knowledge of the complex, evolving internal structure of laser-driven plasma wakes. In this project we developed and demonstrated a suite of optical visualization methods based on well-known methods such as holography, streak cameras, and coherence tomography, but adapted to the ultrafast, light-speed, microscopic world of laser-driven plasma wakes. Our methods output images of laser-driven plasma structures in a single laser shot. We first reported snapshots of low-amplitude laser wakes in Nature Physics in 2006. We subsequently reported images of high-amplitude laser-driven plasma "bubbles", which are important for producing electron beams with low energy spread, in Physical Review Letters in 2010. More recently, we have figured out how to image laser-driven structures that change shape while propagating in a single laser shot. The latter techniques, which use t ...

Download or read book Experimental Studies of Laser Plasma Wakefield Acceleration written by Constantin Aniculaesei and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes experiments that explore the possibility of improving the quality of an electron beam obtained from a laser wakefield accelerator (LWFA) by shaping the longitudinal plasma density profile. Different density profiles have been obtained by employing a range of Laval nozzles with different geometries. These are modelled and numerically simulated under different conditions using Fluent 6.3. Density lineouts from simulations for different heights above the nozzle give the plasma density profile for each experimental condition. The plasma density profile is modified by changing the geometry of the nozzle, the interaction point, the laser beam angle relative to the exit plane of the nozzle and pressure of the gas. In this way the leading up-ramp length of the density profile (that interacts first with the laser) has been varied between 0.47 mm to 1.39 mm and the maximum plasma density varied between 1.29 x 1019 cm−3 to 2.03 x 1019 cm−3. The influence of the density profile parameters on the LWFA process is quantified by monitoring the properties of the generated electron beam. It is shown that the leading ramp of the plasma density profile i.e. the ramp that interacts first with the laser, has a strong influence on the quality of the electron beam. Density profiles with the same peak plasma density but different ramp lengths generate electron beams with a factor of 1.4 difference in charge, 1.1 in electron energy, 2 in pointing and 1.45 in energy spread. Longer ramp lengths enhance the quality of electron beams, which suggest that LWFA injection occurs at the entrance density ramp. Complex density profiles are produced by tilting the nozzle relative to the direction of propagation of the laser. This allows continuous tuning of the peak energy of the electron beam from 135 ± 2MeV up to 171 ± 2MeV. The electron beam energy spread show improvements from 20.7 ± 1.2% to 8.9 ± 0.9%. The charge closely follows the evolution of the energy spread and has a mean value of 0.61 ± 0.16 pC. Experimental results also show that the angular distribution of the electron beam becomes elliptical when the laser focal plane is moved from the edge of the gas jet towards the centre of the density profile. This result is linked to the existence of a distorted LWFA bubble that propagates off-axis therefore affecting the pointing and transverse shape of the electron beam.

Download or read book Laser plasma Interactions Used for the Acceleration of Electrons written by Evan Stuart Dodd and published by . This book was released on 1999 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: