G.N. Kulipanov

Novosibirsk terahertz free electron laser: instrumentation development and experimental achievements

Nowadays, the Novosibirsk free electron laser (NovoFEL) is the most intense radiation source in the terahertz spectral range. It operates in the continuous mode with a pulse repetition rate of up to 11.2 MHz (5.6 MHz in the standard mode) and an average power of up to 500 W. The radiation wavelength can be precisely tuned from 120 to 240 mm with a relative line width of 0.3–1%, which corresponds to the Fourier transform limit for a micropulse length of 40–100 ps. The laser radiation is plane-polarized and completely spatially coherent. The radiation is transmitted to six user stations through a nitrogen-filled beamline. Characteristics of the NovoFEL radiation differ drastically from those of conventional low-power (and often broadband) terahertz sources, which enables obtaining results impossible with other sources, but necessitates the development of special experimental equipment and techniques. In this paper, we give a review of the instrumentation developed for control and detection of high-power terahertz radiation and for the study of interaction of the radiation with matter. Quasi-optic elements and systems, one-channel detectors, power meters, real-time imagers, spectroscopy devices and other equipment are described. Selected experimental results (continuous optical discharge, material and biology substance ablation, real-time imaging attenuated total reflection spectroscopy, speckle metrology, polarization rotation by an artificial chiral structure, terahertz radioscopy and imaging) are also presented in the paper. In the near future, after commissioning another four electron racetracks and two optical resonators, intense radiation in the range from 5 to 240 µm will be available for user experiments.

Lasing in visible and ultraviolet regions in an optical klystron installed on the VEPP-3 storage ring

Abstract Lasing in a wide 2400–6900 A spectral range (from visible to ultraviolet) was reached in the optical klystron OK-4 installed on the VEPP-3 storage ring. OK-4 is the first FEL operating in UV.

Novosibirsk Free Electron Laser—Facility Description and Recent Experiments

The design and operational characteristics of the Novosibirsk free electron laser facility are described. Selected experiments in the terahertz range carried out recently at the user stations are surveyed in brief.

The VEPP-3 storage-ring optical klystron: Lasing in the visible and ultraviolet regions

Abstract Lasing in a wide spectral range (from visible to ultraviolet, 2400–6900 A) was reached in the optical klystron OK-4 installed on the VEPP-3 storage ring. OK-4 is the first FEL operating in UV.

Review of X-ray fluorescent analysis using synchrotron radiation

Abstract The current status of research in X-ray fluorescent analysis using synchrotron radiation (SRXFA) is reviewed. The main schemes of analysis and the background components are considered. The methods of reducing the background, which are based on the use of the specific features of synchrotron radiation, are discussed. The requirements for the elements of the SRXFA apparatus including the source of synchrotron radiation, the monochromator, a chamber for the sample, scanner and the detector are formulated. The engineering solutions which can be used when designing these elements are suggested. The main results obtained by the SRXFA method and the possibilities for their further improvement are discussed.

Status of the INP optical klystron

Abstract The result of recent experiments with the optical klystron OK-2 installed in the storage ring VEPP-3 are presented. The current status, the new magnetic system design OK-3, and some prospects and plans are described.

The dedicated synchrotron radiation source Siberia-2

Abstract A general presentation on the main storage ring of the SRS complex SIBERIA is given. The facility will consist of the 2.5 GeV electron ring SIBERIA-2 with 12 straight sections to accomodate insertion devices. The magnetic lattice is optimized to achieve high btightness of SR. A low horizontal emittance of 7.65×10 −6 cm rad is obtained.

Biological and medical application of SR from the storage rings of VEPP-3 and “Siberia-2”. The origin of specific changes of small-angle X-ray diffraction pattern of hair and their correlation with the elemental content

Abstract X-ray diffraction and fluorescent investigations of human hair were carried out using SR of VEPP-3. The small-angle techniques were used for ecological monitoring and medical diagnostics of pathological states of human organisms with the usage of non-invasive methods for express analysis of biological objects, including human and animal tissues: nails, wool and hair samples. Possibility using of hair fibre diffraction to test for pathological conditions is the subject of this paper. X-ray diffraction data allowed us to suppose the two-component structural model of the hair tissue.

Application of Synchrotron Radiation for Studying Detonation and Shock-Wave Processes

A new method of remote investigation of detonation and shock‐wave processes with the use of synchrotron radiation is proposed. The facility used for the first experiments with measurement of density and small‐angle x‐ray scattering in detonation of condensed explosives is described. The high time and spatial resolution of the techniques proposed allows one to determine the character and mechanism of destruction of the condensed phase and the growth dynamics of new structures, including crystalline ones, in detonation flows. The capabilities of the new technique are described.

Synchrotron Light Sources and Recent Developments of Accelerator Technology

The main aim of the next-generation synchrotron radiation sources is to provide diffraction-limited undulator radiation in the 0.1-4 nm range with an average power of 10-1000 W and monochromaticity of 10(-3)-10(-4). A review of new accelerator technologies that could be used for the construction of such types of synchrotron radiation sources is given.