Characteristics of electron beams produced by the laser wakefield acceleration are presented. The dependence of the electron beam parameters on the laser focal spot size is investigated. The experimental result shows the generation of quasimonoenergetic electron beam although the laser spot size was several times larger than the plasma wavelength. Stable electron beam generation at large laser spots was owing to the stable laser propagation in plasma channels. At a small laser spot, the beam quality is poor and this is attributed to the the filamentation instability of the laser beam.

Dependence of the electron beam parameters on the stability of laser propagation in a laser wakefield accelerator

A technique of laser peen forming on a microscale has been developed, which does not require a confining (tamping) layer. This paper reports on the results of studies carried out on 75-μm-thick steel samples using pulsed Nd:YAG lasers operating at 1,064-, 532- and 355-nm wavelengths and relatively low beam powers of 5, 2.5 and 1.8 W, respectively. Empirical data are presented to demonstrate the active forming mechanism and to characterise the process. The process was found to produce a bending towards the laser beam at any angle of incidence, including at 0° (or parallel) to the surface. A bend angle of up to approximately 28° was possible when the incident angle is 90°. The process was found to be reversible by reverse side irradiation. The results from these experiments have been compared to samples formed using continuous wave thermal laser forming. The laser peen-formed samples do not show evidence of a heat-affected zone seen in thermal laser forming, which, together with thermocouple analysis, indicates that the active laser peen forming process is non-thermal.

http://chriscarey.co.uk/wp-content/uploads/2011/11/Edwards-2009-Laser-peen-forming-without-tamping-layer.pdf

Laser micro peen forming without a tamping layer

The dynamics and energy spectra of electrons driven by a relativistically intense laser pulse are analyzed. The description is based on the numerical solution of the relativistic Newton’s equation with the Lorentz force generated by a strong focused optical field. After the interaction with it, electrons retain a considerable fraction of the energy of their oscillations during the interaction. The electron postinteraction energy spectrum is calculated. The energies in the spectrum high-energy tail are determined by the laser pulse intensity at the focal spot. An approach to estimating absolute values of the laser pulse intensity based on the measurement of the energy spectra of the electrons is proposed.

Electrodynamics of electron in a superintense laser field: New principles of diagnostics of relativistic laser intensity

Results are presented from theoretical analysis and 2D PIC simulations of electron acceleration in a breaking wake plasma wave generated by a short intense laser pulse during its interaction with a finite-length underdense plasma layer. The high energy electron energy spectrum and transverse emittance are obtained. It is shown that, for laser pulse lengths above the plasma wake wavelength, the wakefield-accelerated electrons are further accelerated by the electromagnetic wave.

Electron bunch acceleration in the wake wave breaking regime

Effects of density gradient on the self-injection of plasma electrons in the phase of laser pulse wake for further acceleration, is studied for moderate laser intensities, a0⩽3. It is shown that transverse wave breaking can shorten the length of accelerated electrons, whereas effective longitudinal wave breaking requiring steep plasma density interface increases their total charge. For the considered range of laser intensities, the total charge of electrons injected by wave breaking rises exponentially with a0.

Effects of density gradient on short-bunch injection by wave breaking in the laser wake field acceleration

We study experimentally the interaction of the shortest at present $(23\text{\ensuremath{-}}\mathrm{fs})$, relativistically intense $(20\text{\ensuremath{-}}\mathrm{TW})$, tightly focused laser pulses with underdense plasma. MeV electrons constitute a two-temperature distribution due to different plasma wave-breaking processes at a plasma density of ${10}^{20}\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$. These two groups of electrons are shown numerically to constitute bunches with very distinctive time durations.

Electron acceleration by a nonlinear wakefield generated by ultrashort ( 23 − fs ) high-peak-power laser pulses in plasma

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

T. Homma

Author Tools

Chat about Author

Papers

Electron acceleration by a nonlinear wakefield generated by ultrashort ( 23 − fs ) high-peak-power laser pulses in plasma