All-optical ideas provide a potential to dramatically cut off the size and cost of x-ray light sources to the university-laboratory scale, with the combination of the laser-plasma accelerator and the laser undulator. However, the large longitudinal energy spread of the electron beam from laser-plasma accelerator may hinder the way to high brightness of these all-optical light sources. In this p...

A comprehensive analysis is presented that describes amplification of a seed THz pulse in a single-pass free-electron laser (FEL) driven by a photoinjector. The dynamics of the radiation pulse and the modulated electron beam are modeled using the time-dependent FEL code, GENESIS 1.3. A 10-ps (FWHM) electron beam with a peak current of 50–100 A allows amplification of a 1 kW seed pulse in the fr...

The Magnetron is one of the efficiency high-power microwave source, although the energy conversion efficiency decreases with pulsed-power relativistic electron beam. We study the capability to increase energy conversion efficiency of Relativistic Magnetron by using Transparent Cathode. The Transparent-Cathode consists of independent cathode strips. Each cathode strip caused azimuthal magnetic f...

The variation of current density distribution over the unit cell with direction of the incident beam gives rise to anomalous absorption and other orientation effects in electron diffraction. One of these, the electron induced x-ray emission, was demonstrated to depend on the diffraction condition already in 1962 by Duncumb [1] and a theoretical treatment based on the Bloch wave considerations w...

Background: Neutron contamination is produced in electron beams of linac when tooth or dental materials are located in the path of beam. Objective: This study aims to determine the neutron dose contamination from different dental restoration materials in electron mode of a linac. Material and Methods: In this experimental study, the neutron dose contamination was calculated in the p...

In this paper we propose a new method for measurements of the longitudinal profile of 100 femtosecond electron bunches for X-ray Free Electron Lasers (XFELs). The method is simply the combination of two well-known techniques, which where not previously combined to our knowledge. We use seed 10-ps 1047 nm quantum laser to produce exact optical replica of ultrafast electron bunches. The replica i...

Generation of submillimeter radiation by stimulated Raman scattering in an intense relativistic electron beam subjected to a spatially periodic transverse electric field is examined. The requisite electric field modulation can be obtained by rippling the wall of the conducting drift tube. When the electron beam is subjected to a periodic longitudinal electric field, short wavelength plasmons, r...

A laser pulse propagating in a corrugated plasma channel is composed of spatial harmonics whose phase velocities can be subluminal. The phase velocity of a spatial harmonic can be matched to the speed of a relativistic electron resulting in direct acceleration by the guided laser field in a plasma waveguide and linear energy gain over the interaction length. Here we examine the fully self-consi...

In laser-produced plasmas there are several effects which will scatter a longitudinally probing relativistic electron beam. In vacuum, the laser itself will ponderomotively defocus the electron beam, while in plasma the ponderomotive force can dig an ion channel which would focus the electron beam. In the cases of plasma wave excitation via the beat-wave or wake-field mechanisms, the thermaliza...

Electron Beam Lithography is a well-established tool suitable for the modification of substrate surface chemistry. It therefore follows that the deposition and self-assembly of nanoparticles on a surface can be directed using this method. This work explores the effect of electron dose on the electron beam lithographic patterning of selfassembled monolayers (SAMs) on gold surfaces. Electron beam...