摘要:

The current status of the beam‐driven plasma wakefield accelerators is reviewed. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1842531

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

Current activities (last few years) at different laboratories, towards the development of a laser wakefield accelerator (LWFA) are reviewed, followed by a more in depth discussion of results obtained at the L’OASIS laboratory of LBNL. Recent results on laser guiding of relativistically intense beams in preformed plasma channels are discussed. The observation of mono‐energetic beams in the 100 MeV energy range, produced by a channel guided LWFA at LBNL, is described and compared to results obtained in the unguided case at LOA, RAL and LBNL. Analysis, aided by particle‐in‐cell simulations, as well as experiments with various plasma lengths and densities, indicate that tailoring the length of the accelerator has a very beneficial impact on the electron energy distribution. Progress on laser triggered injection is reviewed. Results are presented on measurements of bunch duration and emittance of the accelerated electron beams, that indicate the possibility of generating femtosecond duration electron bunches. Future challenges and plans towards the development of a 1 GeV LWFA module are discussed. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1842532

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

This paper will review the requirements on advanced accelerator systems as applied to next‐generation linear colliders. The design issues and requirements for TeV‐scale linear colliders will be discussed, and the challenges involved in developing affordable extensions to higher energies, utilizing advanced accelerator concepts, will be presented. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1842533

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

Several dielectric optical acceleration structures that have been designed in recent years are being compared. The unique properties of these structures entail challenging design of an overall acceleration module. Four possible configurations are being analyzed. Two important concepts are discussed: train of micro‐bunches and feedback loop. While the former facilitates acceleration of a large number of electrons, the latter enables energy recovery leading to higher efficiency. Their implications are considered and some rough estimates of luminosity are considered. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1842534

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

A path towards modeling 10–100 GeV plasma accelerator stages is described. Modeling such stages including the self‐consistent evolution of the driver, the plasma dynamics, and the beam loading of the trailing particles necessitates the use of particle methods. In a previous proceedings, I reviewed the status of particle based methods and stated that new methods needed to be developed if one hoped to routinely model the full scale in three‐dimensions of 10+ GeV plasma accelerator stages. In this article, I describe the development of a new fully parallelized algorithm that reproduces the results from standard particle‐in‐cell methods with at least a 100 times savings in CPU time. I also describe how standard methods are being used to discover new physics. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1842535

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

The concept of a high‐gradient plasma wakefield accelerator is considered as an upgrade path for the International Linear Collider, a future linear collider. Basic parameters are presented based on those developed for the SLC “Afterburner.” Basic layout considerations are described and the primary concerns related to the collider operation are discussed. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1842536

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

Operation of a chopper‐prebuncher high voltage injection system and a high gradient 17 GHz linac having an inherent ability to generate 1 degree (162 fs) electron bunches emphasized the need for a simple means of accurately measuring very short electron bunches while also providing on‐line guidance for optimizing the injector and linac bunch length controls. To meet this need, a fast diagnostic for the direct measurement of short bunch longitudinal phase space, with a time resolution of less than 100 fs, has recently been installed on the 17 GHz linac at the MIT Plasma Science and Fusion Center. The diagnostic system, having a high field (0.2 MA/m) circularly polarized 17 GHz beam deflector, is described; images of 17 GHz electron bunches are shown; and bunch charge distributions mapped with a matrix of 150 micron diameter collimators spaced on 240 micron centers (sampling intervals of 40 fs and 0.4&percent; &Dgr;p/p) are presented. The minimum time resolution of this fast diagnostic device is linearly dependent on the emittance limited beam spot size and is, therefore, especially suited for very low beam emittance, ultra short bunch applications. Direct and simple calibration, real time viewing and extreme phase coherence of the RF system are added advantages of this time domain diagnostic. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1842537

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

Atomic, molecular and excimer gas lasers employ variety of pumping schemes including electric discharge, optical, or chemical reactions and cover a broad spectral range from UV to far‐IR. Several types of gas lasers are capable to produce multi‐kilojoule pulses and kilowatts of average power. Among them, excimer and high‐pressure molecular lasers have sufficient bandwidth for producing pico‐ and femtosecond pulses. Projects are under way and prospects are open to bring ultra‐fast gas laser technology to the front lines of the advanced accelerator applications. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1842538

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

In many cases the length over which particles can be accelerated in a laser‐driven plasma accelerator is limited by refraction or diffraction of the driving laser pulse. In order to overcome this limitation the driving pulse must be guided or channeled through the plasma. In this paper we briefly review of the techniques used to guide laser pulses with peak intensities up to 1019W cm−2, and describe recent experimental results. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1842539

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

This tutorial paper discusses, at a basic level, some of the diagnostics used in plasma accelerators laboratories. Covered are measurements of laser beams, using probe laser beams to characterize the plasma itself (as opposed to the plasma wave accelerating structure) in various ways, including density fluctuations in the plasma and also static or near‐static density structures in the plasma. Also covered are laser probe techniques that are especially suitable for studying the properties of the relativistic electron plasma wave that is ultimately the particle accelerator. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1842540

出版商:AIP    

年代:1904

数据来源: AIP