Radiation of the magneto-crystalline undulator

The radiation at grazing incidence of relativistic positively charged particles on the crystal surface in the presence of magnetic field is studied theoretically. The magnetic field is supposed to be parallel to the surface. Dependent on the initial conditions the particle can be captured in the channeling mode and perform periodic oscillations along the surface of the crystal. The spectrum, angular distribution and polarization of radiation are calculated. The emission spectrum of a single particle is discrete and it extends up to very large numbers of harmonics. If the magnetic field is much weaker than the electric field of atoms, the frequency range of radiation of the particle beam does not depend on magnetic field and is defined solely by the energy of the particles and by the surface averaged potential, though the frequency of the first harmonic is defined only by the magnetic field. In case of channeled positrons the characteristic energy of the emitted photons is of order 10?3/2 (eV), where ? is the particle relativistic factor. The main part of radiation is bound to a narrow cone and is polarized largely orthogonal to the surface of the crystal

X-ray Cherenkov radiation under conditions of grazing incidence of relativistic electrons onto a target surface

X-ray Cherenkov radiation in the vicinity of the photoabsorption edge of a target is considered in this workyesBelgorod State Universit

Cr/Sc multilayer radiator for parametric EUV radiation in "water-window" spectral range

The results of experimental investigation of parametric radiation generated by 5.7 MeV electrons in a multilayer structure consisting of 100 Cr/Sc bi-layers deposited on a Si3N4 membrane are presented. The multilayer structure was specially created for generation of parametric radiation with photon energy in "water-window" spectral rang

On X-ray sources based on Cherenkov and quasi-Cherenkov emission mechanisms

A variety of possible schemes of X-ray sources based on Cherenkov like emission mechanisms is considered theoretically. The possibility to increase substantially an angular density of parametric X-ray source under conditions of grazing incidence of emitting relativistic electrons on the reflecting crystallographic plane of a crystalline target is shownye

Effect of anomalous photoabsorption on parametric X-ray radiation from relativistic electrons

Parametric X-ray radiation from relativistic electrons moving in a crystal is theoretically investigated in Bragg geometry. It is shown that the effect of anomalous photoabsorption can manifest itself within this geometry of the scattering of the pseudophoton field of a fast particleye

Crystal Undulator As A Novel Compact Source Of Radiation

A crystalline undulator (CU) with periodically deformed crystallographic planes is capable of deflecting charged particles with the same strength as an equivalent magnetic field of 1000 T and could provide quite a short period L in the sub-millimeter range. We present an idea for creation of a CU and report its first realization. One face of a silicon crystal was given periodic micro-scratches (grooves), with a period of 1 mm, by means of a diamond blade. The X-ray tests of the crystal deformation have shown that a sinusoidal-like shape of crystalline planes goes through the bulk of the crystal. This opens up the possibility for experiments with high-energy particles channeled in CU, a novel compact source of radiation. The first experiment on photon emission in CU has been started at LNF with 800 MeV positrons aiming to produce 50 keV undulator photons.Comment: Presented at PAC 2003 (Portland, May 12-16

Electron-based crystalline undulator

We discuss the features of a crystalline undulator of the novel type based on the effect of a planar channeling of ultra-relativistic electrons in a periodically bent crystals. It is demonstrated that an electron-based undulator is feasible in the tens of GeV range of the beam energies, which is noticeably higher than the energy interval allowed in a positron-based undulator. Numerical analysis of the main parameters of the undulator as well as the characteristics of the emitted undulator radiation is carried out for 20 and 50 GeV electrons channeling in diamond and silicon crystals along the (111) crystallographic planes.Comment: 16 pages, 8 figures, Latex, IOP styl

X-ray generation from relativistic electrons passing through thin targets in cyclical accelerators

The characteristics of quasi-monochromatic tunable X-ray sources based on multipasses of electrons through thin targets installed in cyclical accelerators are discussed. An internal bremsstrahlung radiator coupled with a multilayer X-mirror placed outside the accelerator vacuum chamber is used to produce tunable, narrow spectrayesBelgorod State Universit