High performance TeV energy electron / positron colliders (LC) are the first machines to require online, non-invasive beam size monitors for micron and submicron for beam phase space optimization. Typical beam densities in the LC are well beyond the threshold density for single pulse melting and vaporization of any material, making conventional wire scanners ineffective. Using a finely focused,...

Megavoltage electron beams represent an important treatment modality in modern radiotherapy, often providing a unique option in the treatment of superficial tumours (less than 5 cm deep). Electrons have been used in radiotherapy since the early 1950s, first produced by betatrons and then by microtrons and linacs. Modern high energy linacs typically provide, in addition to two megavoltage photon...

A comparison is made between the interaction of electron bunches and intense laser pulses with plasma. The laser pulse is modelled with photon kinetic theory, i.e. a representation of the electromagnetic field in terms of classical quasi-particles with space and wave number coordinates, which enables a direct comparison with the phase space evolution of the electron bunch. Analytical results ar...

The goal of Task Group 25 (TG-25) of the Radiation Therapy Committee of the American Association of.Physicists in Medicine (AAPM) was to provide a methodology and set of procedures for a medical physicist performing clinical electron beam dosimetry in the nominal energy range of 5-25 MeV. Specifically, the task group recommended procedures for acquiring basic information required for acceptance...

In the interaction of a 30 fs, 40 TW Ti:sapphire Hercules laser focused to the intensity of 1019 W/cm2onto a supersonic He gas jet, we observed quasi-monoenergetic electron beams with energy up to 300 MeV and an angular divergence of 10 mrad. We found that the initial plasma density significantly affects the resultant electron beam. For plasma densities ranging between 2×1019 to 3.5×1019 cm−3, ...

A new class of synchrotron light sources, based on the use of superconducting electron linear accelerators and beam recirculation with energy recovery, is currently under active consideration. The injectors for such accelerators must deliver high brightness electron beams with appropriate RF time structure and the full average beam current. Various photoemission cathodes have been demonstrated ...

Introduction: In electron beam treatment, because of the non-point electron beam source, inverse-square law cannot be applied for dosimetry in different treatment intervals. Therefore, providing source-surface distance (SSD) charts in all clinics is of paramount importance. This study aimed to determine the effective SSD for various electron beam energies and field sizes and to...

The interaction of incident electron beams with molybdenum hexacarbonyl (Mo(CO)6) adsorbed on thin, dehydroxylated alumina films grown on a molybdenum substrate is studied in ultrahigh vacuum using primarily temperature-programmed desorption (TPD) and reflection– absorption infrared spectroscopies (RAIRS). It is found that electron beams induce decarbonylation, forming both subcarbonyls and a s...