Randomly distributed lattice point defects such as supersaturated vacancies (SVs) and Frenkel-pairs (FPs, an interstitial and a vacancy) can be simultaneously introduced into the crystal by energetic beam irradiation in outer space and/or nuclear reactors, but their behavior has not been fully understood. Using a high-voltage electron microscope equipped with a laser (laser-HVEM), we show the s...

Electron beam irradiation is well known to induce damage in materials. The structural transformation involved in the damage is usually believed to be an irreversible solid state chemical reaction. Here we use in situ transmission electron microscopy (TEM) combined electron-energy loss spectroscopy (EELS) technique in an aberration-corrected TEM to track the structural transformation in spinel M...

Background: The aim of present study was to analyze the effectiveness of electron filters in the Telecobalt radiotherapy treatment by simulation technique.  Materials and Methods: The BEAMnrc Monte Carlo code was used to simulate the electron filters of thickness of 0.5 gm/cm2 below the trimmer bar for 35 × 35 cm2 field size in Theratron Equinox-80 telecobalt unit. The electron filters were mad...

Experiments where a high-voltage electron beam emitted by a spacecraft in the low-density magnetosphere is used to probe the magnetospheric configuration could greatly enhance our understanding of the near-Earth environment. Their challenge, however, resides in the fact that the background magnetospheric plasma cannot provide a return current that balances the electron beam current without char...

I summarize recent electron-cloud and coupled-bunch instability simulation studies for KEKB and SuperKEKB. The possible suppression of the electron-cloud build up inside quadrupole magnets by means of 4 permanent dipoles or by a super-imposed solenoid is investigated for the LER positron beam. Also studied is the electron accumulation in three different types of solenoidal fields, namely for a ...

INTRODUCTION In radiotherapy, megaelectron volt (MeV) electrons are employed for treatment of superficial cancers. Magnetic fields can be used for deflection and deformation of the electron flow. A magnetic field is composed of non-uniform permanent magnets. The primary electrons are not mono-energetic and completely parallel. Calculation of electron beam deflection requires using complex mathe...

A new mechanism is reported that increases electron energy gain from a laser beam of ultrarelativistic intensity in underdense plasma. The increase occurs when the laser produces an ion channel that confines accelerated electrons. The frequency of electron oscillations across the channel is strongly modulated by the laser beam, which causes parametric amplification of the oscillations and enhan...

The SPARC-EBIT (fig.1) is an Electron Beam Ion Trap (from DREEBIT, Dresden) that will be used for tests and offline measurements, firstly for HITRAP, and later for SPARC (Stored Particle Atomic physics Research Collaboration). In the EBIT the ions are produced by electron impact ionisation of gas atoms by an intense electron beam. The magnetic field of a permanent magnet arrangement focuses the...

Much of the tremendous progress in integrated circuit technology and performance over the past 30 years has been fuelled by the progress in lithography. The ability to print increasingly smaller features has enabled higher speed transistors, higher packing densities and lower power dissipation in CMOS circuits. The productivity of the integrated circuit industry has been on a very steep perform...

The channelspark, a low accelerating voltage, high current electron beam accelerator, has been used for ablation of materials applied to thin film deposition. The channelspark operates at accelerating voltages of 10 to 20 kV with ;1500 A beam currents. The electron beam ionizes a low-pressure gas fill ~10–20 mTorr Ar or N2) to compensate its own space charge, allowing ion focused transport. Abl...