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Samples for analysis (optical thin section) were prepared from several core intervals of Lake Kucherlinskoe bottom sediments with well visually distinguished separate annual layers (varves). The annual nature of the layers was previously confirmed by the coincidence of varvechronology (layer counting) with isotopic dating (Cs-137, Pb-210, C-14). The thickness of the annual layers ranged from <1 to 3-4 mm. To study the internal structure of annual layers, we used the scanning μ_XRF-SR with focusing x-ray optics (polycapillary lenses). The experiments were carried out at the Siberian Center for Synchrotron and Terahertz Research (INP SB RAS, Novosibirsk) and the Kurchatov Complex of Synchrotron-Neutron Research (KISI, Moscow) using a confocal X-ray microscope, as well as at the Shanghai Synchrotron Center at the μ_XRF-SR station. The monochromatic excitation energy of 17 and 22 keV was used. The size of the scanning spot was determined by the used focusing polycapillary lenses and amounted to 15-25 microns. The scanning step was 50 or 100 µm. The measurement time was determined by the counting rate and ranged from 10 to 100 seconds per point. Scanning profiles were superimposed on the optical images of the thin section obtained with a high-resolution scanner. Given that the thickness of the thin section is less than 20 µm, a change in elemental composition reflects visual changes in the structure of the bottom sediment. Thus, while tracking visual changes in the structure and elemental composition of individual annual layers, seasonal geochemical features and boundaries between the layers can be distinguished. The obtained changes in the elemental composition made it possible to calculate the annual layers by the found lithological and geochemical indicators of the layer boundaries (Rb / Sr ratio). A geochemical trace of a catastrophic seismic event, the Mongolian earthquake of 1761, was found in the section of bottom sediments. [ABSTRACT FROM AUTHOR]

The SR-XRFA method has been first used to study the elemental composition of the Syringa L. (Lilac) in the urban ecosystem of Novosibirsk, under background conditions, and in soil samples. About 19 elements have been found in the leaves and shoots of the Syringa species – S. josikaea and S. vulgaris, represented by the three cultivars: cv. 'Pamyat' o Kirove', cv. 'Olimpiada Kolesnikova', and cv. 'Nadezhda', growing in urban and background conditions. In plants, the concentration of Mn, Fe, Cr, Br, Rb, and Nb increased and that of Zn and Mo decreased under technogenic impact as compared with the "background". In urban conditions, the strongest heavy metal pollution was recorded for S. vulgaris cv. 'Nadezhda'. The S. vulgaris cv. 'Pamjat' o Kirove' samples were most resistant to pollution and thus can be recommended both as reference and for use in green construction. [ABSTRACT FROM AUTHOR]

A conceptual design of the "Structural Diagnostics" diffraction beamline 1-2 for "SKIF" synchrotron radiation facility (Koltsovo, Novosibirsk area, Russia) is presented. The beamline will be dedicated to various diffraction techniques (powder X-ray diffraction, single-crystal X-ray diffraction and SAXS). All the techniques will be implemented in in situ and operando modes to enable real-time monitoring of chemical, physical, or engineering processes. The paper describes scientific scope of the beamline, basic X-ray optical scheme and equipment that will be available at the end-stations. Results of simulations and ray tracing aimed at the optimization of the instrumental resolution and flux are also given. [ABSTRACT FROM AUTHOR]

The X-band Electron Paramagnetic Resonance (EPR) spectroscopy endstation at the Novosibirsk Free Electron Laser (NovoFEL) facility is capable for steady-state (CW) EPR and time-resolved (TR) continuous wave EPR experiments. Recently several upgrades in experimental hardware and software have been done, aiming to more productively use the time of experimental session and to increase the control of experimental parameters during the session. Firstly, we installed detectors with different time resolution for tracking radiation produced by NovoFEL. Secondly, on the basic of fsc2 program, we implemented a possibility of a simultaneous use of two oscilloscopes, configured at different timescale and/or sensitivity. Finally, we developed software for on-the-fly CW and TR experimental data viewing and treatment. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance (SPR) microscopy is one of the most sensitive label-free microscopy methods, however with low lateral resolution. This drawback is primarily caused by the fact that surface plasmon polaritons (SPPs) excited by terahertz (THz) radiation propagate macro distances (about ∼100 1) from their excitation spot, thereby blurring the observed region, like with a scattering medium. To eliminate this disadvantage, we adapt a method known as ghost imaging (GI), which is notable for its tolerance to environmental aberrations between the object and camera. We propose an optical scheme of SPR microscopy for the THz range with an additional optical arm to implement the classical GI and provide an analysis of factors affecting the image quality. To implement the classical GI in the THz range, we propose to use the Novosibirsk free electron laser (NovoFEL) as a THz radiation source. The high beam power of the NovoFEL provides a speckle structure with a pronounced profile, which is required to achieve a high level of contrast in the obtained image. Moreover, the large coherence length of the NovoFEL radiation is necessary to ensure a large degree of correlation between the beams emerging from the beam splitter, which allows reconstructing an image with a lower noise level. [ABSTRACT FROM AUTHOR]

The propagation length of surface plasmon polaritons (SPPs) increases with wavelength, which makes it possible to use radiation from the far-infrared and terahertz ranges to create communication devices employing SPPs as carriers of information. In this paper, we consider methods for implementing the multiplex transmission of information along cylindrical conductors using a combination of SPPs with orbital angular momentum and present experimental setups for the experiments on the Novosibirsk free electron laser. [ABSTRACT FROM AUTHOR]

A review is given of recent experiments in the field of terahertz optics conducted on the Novosibirsk free electron laser (NovoFEL). The NovoFEL facility configuration is briefly described, and radiation characteristics of the three laser systems of the facility are presented. Considerable attention has been paid to the development and testing of quasi-optical elements designed for this range and methods to produce high-power beams of terahertz radiation with a given mode composition. The use of terahertz radiation in the spectroscopy of gases and semiconductors and generation and research on surface plasmon polaritons, as well as applying the latter in surface study and communication applications, are described. [ABSTRACT FROM AUTHOR]

A new variable period undulator of unique design was developed and built recently at Budker INP. It will replace the electromagnetic undulator in use now on the second FEL of the Novosibirsk FEL facility. As a result, the FEL tunability range will be substantially extended. In this paper, we present the results of measurements of the undulator magnetic field for different periods and discuss ways to reduce the field errors, which include sorting of magnets, weakening of undulator edge poles, and using of steering coils. [ABSTRACT FROM AUTHOR]

The Free Electron Laser (FEL) based on multi-turn microtron-recuperator is currently operating in Novosibirsk. For successful operation of the facility, a specialized control system was developed. The software part of this system consists of a set of different program modules. For ensuring program connection between a client and server parts of the control software, the Channel Access protocol from the EPICS framework was employed. Features and examples of using this protocol without utilizing the whole EPICS system are described in this article. [ABSTRACT FROM AUTHOR]

The high-power Free Electron Laser (FEL) based on a multi-turn microtron-recuperator is currently operating in Novosibirsk [1]. The radiation of the FEL is used for carrying out experiments in different areas of physics, biology, and chemistry. The radiation is transported to all user stations using one transportation system, referred to as the "radiation optical channel". To ensure radiation transportation to the required user station, this optical channel contains a set of special mechanical units (mirrors and shutters). The states of all these units determine the track of radiation propagation from its source to the required user station. [ABSTRACT FROM AUTHOR]

A new normal-conducting, CW, thermocathode RF gun has been developed and tested recently at Budker Institute of Nuclear Physics. Providing an average current of up to 100 mA, this device will be used to upgrade the injector of the Novosibirsk FEL facility. Simulation of beam dynamics in the RF gun and its beamline was performed, the space-charge forces taken into account. Comparison of the simulation results and experimental measurements is presented in this paper. [ABSTRACT FROM AUTHOR]

The hyperfine spectral structure of radiation−laser modes of the Novosibirsk terahertz free electron laser (NovoFEL) has been measured in two its main operating regimes: resonance unstable regime with maximum output power and stabilized regime with maximum spectral power. The monochromaticity of the mode structure is shown to be practically independent of the laser operating regime and reaches a value of 2·10−8. The mode composition weakly depends on the operating regime for a well aligned electron beam and consists of many longitudinal TEMq00modes (supermode). In the case of a poorly aligned electron beam, transverse modes of the optical cavity are also excited; its intensities strongly increase in the resonance regime. [ABSTRACT FROM AUTHOR]