Download or read book Beam driven Plasma Wakefield Acceleration in AWAKE written by Linbo Liang and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Plasma Wakefield Acceleration of an Intense Positron Beam written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Plasma Wakefield Accelerator (PWFA) is an advanced accelerator concept which possess a high acceleration gradient and a long interaction length for accelerating both electrons and positrons. Although electron beam-plasma interactions have been extensively studied in connection with the PWFA, very little work has been done with respect to positron beam-plasma interactions. This dissertation addresses three issues relating to a positron beam driven plasma wakefield accelerator. These issues are (a) the suitability of employing a positron drive bunch to excite a wake; (b) the transverse stability of the drive bunch; and (c) the acceleration of positrons by the plasma wake that is driven by a positron bunch. These three issues are explored first through computer simulations and then through experiments. First, a theory is developed on the impulse response of plasma to a short drive beam which is valid for small perturbations to the plasma density. This is followed up with several particle-in-cell (PIC) simulations which study the experimental parameter (bunch length, charge, radius, and plasma density) range. Next, the experimental setup is described with an emphasis on the equipment used to measure the longitudinal energy variations of the positron beam. Then, the transverse dynamics of a positron beam in a plasma are described. Special attention is given to the way focusing, defocusing, and a tilted beam would appear to be energy variations as viewed on our diagnostics. Finally, the energy dynamics imparted on a 730 [micro]m long, 40 [micro]m radius, 28.5 GeV positron beam with 1.2 x 10[sup 10] particles in a 1.4 meter long 0-2 x 10[sup 14] e[sup -]/cm[sup 3] plasma is described. First the energy loss was measured as a function of plasma density and the measurements are compared to theory. Then, an energy gain of 79 [+-] 15 MeV is shown. This is the first demonstration of energy gain of a positron beam in a plasma and it is in good agreement with the predictions made by the 3-D PIC code. The work presented in this dissertation will show that plasma wakefield accelerators are an attractive technology for future particle accelerators.
Download or read book Experimental Investigations of Beam Driven Plasma Wakefield Accelerators written by Navid Vafaei-Najafabadi and published by . This book was released on 2016 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: A plasma wakefield accelerator (PWFA) uses a plasma wave (a wake) to accelerate electrons at a gradient that is three orders of magnitude higher than that of a conventional accelerator. When the plasma wave is driven by a high-density particle beam or a high-intensity laser pulse, it evolves into the nonlinear blowout regime, where the driver expels the background plasma electrons, resulting in an ion cavity forming behind the driver. This ion cavity has ideal properties for accelerating and focusing electrons. One method to insert electrons into this highly-relativistic, transient structure is by ionization injection. In this method, electrons resulting from further ionization of the ions inside the wake are trapped and accelerated by the wakefield. These injected electrons absorb the energy of the wake, resulting in a reduced accelerating field amplitude; this phenomenon is known as beam loading. This thesis discusses experiments that demonstrate how ionization injection can, on the one hand, lead to excessive beam loading and be a detriment to a PWFA, while on the other hand, it may be taken advantage of to produce bright electron beams that will be necessary for applications of a PWFA to a free electron laser (FEL) or a collider. These experiments were part of the FACET Campaign at the SLAC National Accelerator Laboratory and used FACET's 3 nC, 20.35 GeV electron beam to field ionize the plasma source and drive a wake. In the first experiment, the plasma source was a 30 cm column of rubidium (Rb) vapor. The low ionization potential and high atomic mass of Rb made it a suitable candidate as a plasma source for a PWFA. However, the low ionization potential of the Rb+ ion resulted in continuous ionization of Rb+ and injection of electrons along the length of the plasma. This resulted in heavy beam-loading, which reduced the strength of the accelerating field by half, making the Rb source unusable for a PWFA. In the second experiment, the plasma source was a column of lithium (Li) vapor bound by cold helium (He) gas. Here, the ionization injection of He electrons in the 10 cm boundary region between Li and He led to localized beam loading and resulted in an accelerated electron beam with high energy (32 GeV), a 10% energy spread, and an emittance an order of magnitude smaller than the drive beam. Particle-in-cell simulations indicate that the beam loading can be further optimized by reducing the injection region even more, which can lead to bright, high-current, low-energy-spread electron beams.
Download or read book Challenges and Goals for Accelerators in the XXI Century written by Oliver Brning 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 Plasma Wake Excitation by Lasers Or Particle Beams written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma accelerators may be driven by the ponderomotive force of an intense laser or the space-charge force of a charged particle beam. Plasma wake excitation driven by lasers or particle beams is examined, and the implications of the different physical excitation mechanisms for accelerator design are discussed. Plasma-based accelerators have attracted considerable attention owing to the ultrahigh field gradients sustainable in a plasma wave, enabling compact accelerators. These relativistic plasma waves are excited by displacing electrons in a neutral plasma. Two basic mechanisms for excitation of plasma waves are actively being researched: (i) excitation by the nonlinear ponderomotive force (radiation pressure) of an intense laser or (ii) excitation by the space-charge force of a dense charged particle beam. There has been significant recent experimental success using lasers and particle beam drivers for plasma acceleration. In particular, for laser-plasma accelerators (LPAs), the demonstration at LBNL in 2006 of high-quality, 1 GeV electron beams produced in approximately 3 cm plasma using a 40 TW laser. In 2007, for beam-driven plasma accelerators, or plasma-wakefield accelerators (PWFAs), the energy doubling over a meter to 42 GeV of a fraction of beam electrons on the tail of an electron beam by the plasma wave excited by the head was demonstrated at SLAC. These experimental successes have resulted in further interest in the development of plasma-based acceleration as a basis for a linear collider, and preliminary collider designs using laser drivers and beam drivers are being developed. The different physical mechanisms of plasma wave excitation, as well as the typical characteristics of the drivers, have implications for accelerator design. In the following, we identify the similarities and differences between wave excitation by lasers and particle beams. The field structure of the plasma wave driven by lasers or particle beams is discussed, as well as the regimes of operation (linear and nonlinear wave). Limitations owing to driver emittance are also discussed.
Download or read book Frontiers in High Energy Density Physics written by National Research Council and published by National Academies Press. This book was released on 2003-05-11 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent scientific and technical advances have made it possible to create matter in the laboratory under conditions relevant to astrophysical systems such as supernovae and black holes. These advances will also benefit inertial confinement fusion research and the nation's nuclear weapon's program. The report describes the major research facilities on which such high energy density conditions can be achieved and lists a number of key scientific questions about high energy density physics that can be addressed by this research. Several recommendations are presented that would facilitate the development of a comprehensive strategy for realizing these research opportunities.
Download or read book Hot Spots and Dark Current in Advanced Plasma Wakefield Accelerators written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Dark current can spoil witness bunch beam quality and acceleration efficiency in particle beam-driven plasma wakefield accelerators. In advanced schemes, hot spots generated by the drive beam or the wakefield can release electrons from higher ionization threshold levels in the plasma media. Likewise, these electrons may be trapped inside the plasma wake and will then accumulate dark current, which is generally detrimental for a clear and unspoiled plasma acceleration process. The strategies for generating clean and robust, dark current free plasma wake cavities are devised and analyzed, and crucial aspects for experimental realization of such optimized scenarios are discussed.
Download or read book 9 GeV Energy Gain in a Beam driven Plasma Wakefield Accelerator written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An electron beam has gained a maximum energy of 9 GeV per particle in a 1.3 m-long electron beam-driven plasma wakefield accelerator. The amount of charge accelerated in the spectral peak was 28.3 pC, and the root-mean-square energy spread was 5.0%. The mean accelerated charge and energy gain per particle of the 215 shot data set was 115 pC and 5.3 GeV, respectively, corresponding to an acceleration gradient of 4.0 GeV m-1 at the spectral peak. Moreover, the mean energy spread of the data set was 5.1%. Our results are consistent with the extrapolation of the previously reported energy gain results using a shorter, 36 cm-long plasma source to within 10%, evincing a non-evolving wake structure that can propagate distances of over a meter in length. Wake-loading effects were evident in the data through strong dependencies observed between various spectral properties and the amount of accelerated charge.
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 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 Phase Space Dynamics in Plasma Based Wakefield Acceleration written by Xinlu Xu and published by Springer Nature. This book was released on 2020-01-02 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores several key issues in beam phase space dynamics in plasma-based wakefield accelerators. It reveals the phase space dynamics of ionization-based injection methods by identifying two key phase mixing processes. Subsequently, the book proposes a two-color laser ionization injection scheme for generating high-quality beams, and assesses it using particle-in-cell (PIC) simulations. To eliminate emittance growth when the beam propagates between plasma accelerators and traditional accelerator components, a method using longitudinally tailored plasma structures as phase space matching components is proposed. Based on the aspects above, a preliminary design study on X-ray free-electron lasers driven by plasma accelerators is presented. Lastly, an important type of numerical noise—the numerical Cherenkov instabilities in particle-in-cell codes—is systematically studied.
Download or read book Ionization Injection Plasma Wakefield Acceleration written by Yunfeng Xi and published by . This book was released on 2016 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma-based acceleration, either driven by laser (LWFA) or driven by electron beam (PWFA) has the potential of accelerating electrons to GeV in a few cen- timeters. This allows construction of table-top accelerator which can be applied to build light source such as free electron laser (FEL) or high energy particle collider. The driver bunch loses energy to plasma when driving a wake. The following wit- ness bunch injected at correct phase will be accelerated. Here we report a novel injection scheme, laser-ionization injection where the witness bunch is formed by laser-ionizing higher-threshold gas such as He. Simulation and numerical calcula- tion is presented to evaluate the beam quality, the beam emittance is estimated to be 10 8 mrad. Experimental key issues such as timing synchronization of laser pulse and electron bunch and eliminate "dark current" are taken care of before the plasma acceleration experiment is carried out. Two beams are synchronized to 100-fs level via plasma radiation observation and Electro-Optic Sampling (EOS). "Dark current" is reduced to trivial level by tuning plasma density and driver bunch configuration. We observed 1 GeV gain of witness bunch with 5% energy spread.
Download or read book Physics at the Terascale written by Ian Brock and published by John Wiley & Sons. This book was released on 2011-05-04 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by authors working at the forefront of research, this accessible treatment presents the current status of the field of collider-based particle physics at the highest energies available, as well as recent results and experimental techniques. It is clearly divided into three sections; The first covers the physics -- discussing the various aspects of the Standard Model as well as its extensions, explaining important experimental results and highlighting the expectations from the Large Hadron Collider (LHC). The second is dedicated to the involved technologies and detector concepts, and the third covers the important - but often neglected - topics of the organisation and financing of high-energy physics research. A useful resource for students and researchers from high-energy physics.
Download or read book Demonstrating High Transformer Ratio Beam driven Plasma Wakefield Acceleration written by Gregor Loisch and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Start to end Simulations of Hybrid Laser and Beam Driven Plasma Wakefield Acceleration and Free Electron Lasers written by Georg Wittig and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutrino Cosmology written by Julien Lesgourgues and published by Cambridge University Press. This book was released on 2013-02-21 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: A self-contained guide to the role played by neutrinos in the Universe and how their properties influence cosmological and astrophysical observations.
