6 LLE Review, Volume 73 A streak camera is an electro-optic instrument capable of resolving high-speed, low-repetition-rate, pulsed laser phenomena. The basis of the instrument is a streak tube. The image of the light to be analyzed is focused onto a photocathode at the input end of the streak tube. The photocathode emits electrons in response to the intensity of the light. The electrons, focus...

For solving the atomic structure of organic molecules such as small proteins which are difficult to crystallize, the use of a jet of doped liquid helium droplets traversing a continuous high energy electron beam is proposed as a means of obtaining electron diffraction patterns (serial crystallography). Organic molecules (such as small proteins) within the droplet (and within a vitreous ice jack...

An electron beam passing through a metamaterial structure is predicted to generate reversed Cherenkov radiation, an unusual and potentially very useful property. We present an experimental test of this phenomenon using an intense electron beam passing through a metamaterial loaded waveguide. Power levels of up to 5 MW are observed in backward wave modes at a frequency of 2.40 GHz using a one mi...

Low intensity beams are generated with a 18 MeV Sband electron linear accelerator at Osaka Prefecture University. The minimum charge of electrons in a pulsed beam is about several aC. Study has been made to establish the methods for measuring the intensity and the spatial profile of the beam at electron charges of a beam in aC to pC regions. In pC region a beam monitor using a charge-sensitive ...

In our experiment, it was observed that silicon nanocrystal rapidly grows with irradiation of electron beam on amorphous silicon film prepared by pulsed laser deposition, and shape of silicon nanocrystal is usually sphere in smaller nanoscale with less exposure time under electron beam, in which the quantum dots are prepared in nanoscale near 3 nm. In the electron interaction process, it was in...

We have used a low-energy positron beam to identify and quantify the dominant vacancy defects in InN layers grown on Al2O3 by molecular beam epitaxy. By applying both continuous and pulsed positron beams, we can show that In vacancies are formed during the crystal growth. Their concentration decreases from B5 10 to below 10 cm 3 with increasing layer thickness (120–800 nm). The In vacancy conce...

At the electron stretcher accelerator ELSA of Bonn University an external fixed target experiment using a polarized electron beam has been started. To provide a polarized beam with sufficient intensity a dedicated source for polarized electrons is used (with a GaAs-AlGaAs superlattice photocathode). To prevent depolarization during acceleration in the circular accelerators several depolarizing ...

* [email protected] Abstract The generation of an ultrashort relativistic electron bunch from a strong laser-plasma interaction have been studied by particle-in-cell simulations and observed experimentally. The electron beam was generated from the plasma created by focusing a Ti: sapphire 50fs 12 TW laser pulse at the edge of helium gas jet expanded into the vacuum from a pulsed supers...

This article presents a new type of low-energy crossed-beam electron spectrometer for measuring angular differential cross sections of electron-impact excitation of atomic and molecular targets. Designed for investigations at energies close to excitation thresholds, the spectrometer combines a pulsed electron beam with the time-of-flight technique to distinguish between scattering channels. A l...