One of the major considerations in planning photoproduction experiments is the choice of technique for generating the photon beam. Several possibilities exist, chieey Compton-backscattered laser beams, tagged and untagged bremsstrahlung, and coherent bremsstrahlung from a crystal. In a coherent bremsstrahlung beam, collimation can be used to suppress the incoherent component and to narrow the e...

A novel method of electron beam cooling is considered which can be used for linear colliders. The electron beam is cooled during collision with focused powerful laser pulse. With reasonable laser parameters (laser flash energy about 10 J) one can decrease transverse beam emittances by a factor about 10 per one stage. The ultimate transverse emittances are much below of that given by other metho...

To date active research on laser-driven plasma-based accelerators have achieved great progress on production of high-energy, high-quality electron and photon beams in a compact scale. Such laser plasma accelerators have been envisaged bringing a wide range of applications in basic, medical and industrial sciences. Here inheriting the groundbreaker's review article on "Laser Acceleration and its...

BackgroundOne of the most significant Intensity Modulated Radiation Therapy treatment benefits is a high target to normal tissue dose ratio. To improve this advantage, an additional accessory such as a compensator is used to delivering doses. Compensator-based IMRT treatment is usually operated with an energy higher than 10 MV. Photoneutrons, which have high linear energy transfer and radiobiol...

Atomic-field bremsstrahlung has been studied with a longitudinally polarized electron beam. The correlation between the initial orientation of the electron spin and the angle of photon polarization has been measured at the photon high energy tip region. In the time reversal this corresponds to a so-far unobserved phenomenon of production of longitudinally polarized electrons by photoionization ...

PURPOSE Since the first publications on intensity modulated radiation therapy (IMRT) in the early 1980s almost all efforts have been focused on fairly time consuming dynamic or segmental multileaf collimation. With narrow fast scanned photon beams, the flexibility and accuracy in beam shaping increases, not least in combination with fast penumbra trimming multileaf collimators. Previously, expe...

A photon collider luminosity and its energy are determined by the parameters of an electron-electron linear collider (energy, power, beam emittances) and collision effects. The main collision effect is the coherent e+e− pair creation. At low energies (2E< 0.5–1 TeV) this process is suppressed due to repulsion of electron beams. In this region Lγγ(z > 0.65) ≥ 1035cm−2s−1 is possible (1033 − 1034...

Introduction In this study, we aimed to assess the medium-term energy stability of a 6MV Elekta CompactTM linear accelerator. To the best of our knowledge, this is the first published article to evaluate this linear accelerator in terms of energy stability. As well as investigating the stability of the linear accelerator energy over a period of several weeks, the results will be useful for esti...

We present a preliminary analysis of the photon beam asymmetry observable (Σ) from the photoproduction reaction channel γn → π−p. This new data was obtained using the near-4π CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Laboratory, USA, employing a linearly polarised photon beam with an energy range 1.1 2.3 GeV. The measurement will provide new data to address the poorly established ...