The accurate calculation of synchrotron radiation from an undulator is a common problem and numerous codes have been developed that describe the radiation from analytic and measured undulator fields. However, for very long undulator systems there is not a suitable code that can handle the amount of data in a convenient manner and which runs in a practically realisable time limit. The developmen...

The intensity of undulator radiation, not amplified by the FEL interaction, can be larger than the maximum FEL signal in the case of an X-ray FEL. In the commissioning of a SASE FEL it is essential to extract an amplified signal early to diagnose eventual misalignment of undulator modules or errors in the undulator field strength. We developed a numerical code to calculate the radiation pattern...

The accurate calculation of synchrotron radiation from an undulator is a common problem and numerous codes have been developed that describe the radiation from analytic and measured undulator fields. However, for very long undulator systems there is not a suitable code that can handle the amount of data in a convenient manner and which runs in a practically realisable time limit. The developmen...

This paper is the review of our study published earlier in Acta Phys. Polon. A 121, 522 (2012) [7], Phys Lett 378, 1364 (2014) [25], and [1]. It’s aim to pay attention new possibilities related producing types THz generators. The suggested effects are result combining two effects: Gunn-effect a material such as GaAs undulator-like radiation, or 'pumping wave' acting on electrons which undulator...

This paper discusses the undulator radiation emitted by high-energy positrons during planar channeling in periodically bent crystals. We demonstrate that the construction of the undulator for positrons with energies of 10 GeV and above is only possible if one takes into account the radiative energy losses. The frequency of the undulator radiation depends on the energy of the particle. Thus the ...

This paper discusses the undulator radiation emitted by high-energy positrons during planar channeling in periodically bent crystals. We demonstrate that the construction of the undulator for positrons with energies of 10 GeV and above is only possible if one takes into account the radiative energy losses. The frequency of the undulator radiation depends on the energy of the particle. Thus the ...

Obtaining precise values of the undulator parameter, K, is critical for producing high-gain FEL radiation. At the LCLS [1], where the FEL wavelength reaches down to 1.5 Å, the relative precision of K must satisfy (ΔK/K)rms 0.015% over the full length of the undulator. Transverse misalignments, construction errors, radiation damage, and temperature variations all contribute to errors in the mean...

A new generation of synchrotron radiation light sources covering the VUV, soft x-ray, and hard x-ray speclrai regions is under construction in several countries. These sources are designed specifically to use periodic magnetic undulators and low-emittance electron or positron beams to produce high-brightness near-diffraction-limited synchrotron radiation beams. Some of the novel features of the...

The scheme for accurate quantitative treatment of the radiation from a crystalline undulator in presence of the dechanneling and the photon attenuation is presented. The number of emitted photons and the brilliance of electromagnetic radiation generated by ultra-relativistic positrons channeling in a crystalline undulator are calculated for various crystals, positron energies and different bend...