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The project of the station of synchrotron radiation of the second stage Plamya-2 for the Siberian ring photon source SKIF is based on the experience gained during the development of the station "Plamya" on the storage ring VÉPP-4 at the Siberian Center for Synchrotron Radiation (SR). The station is designed to study the processes of combustion and thermal decomposition of various organic compounds by the method of photoionization mass spectrometry using vacuum ultraviolet (VUV) synchrotron radiation. The use of selective photoionization by VUV radiation in the molecular beam method of sampling from the reaction zone in flames or pyrolyzers makes it possible to identify and quantify the concentrations of atoms, radicals, and other labile and short-lived compounds, which provides key information on chemical transformations under conditions of high-speed combustion and thermal decomposition. The paper considers the possibility of using various SR generators available on the SKIF storage ring, as well as the optical scheme of the station and the conceptual design of its front-end. The experimental results of measuring photon fluxes for the Plamya station and the calculated photon fluxes on the sample for the Plamya-2 station are also presented. [ABSTRACT FROM AUTHOR]

The improved spatial coherence of a synchrotron radiation beam was shown experimentally to stimulate additional diffuse scattering of x rays diffracted from x-ray multilayer mirrors. Although the large-scale (tens of microns) roughness does not affect Bragg diffraction from multilayers, its presence causes phase shifts at the wave packet front. This leads to partial decay of the coherent wave packet and creates additional diffuse scattering. Additional scattering from this mechanism was observed at angles of incidence corresponding to the Bragg and Kiessig maximum angles. The properties of this scattering caused by large-scale roughness, observed due to improved x-ray beam spatial coherence, were shown experimentally to be different from those of diffuse scattering previously reported when the incoming or outgoing angle is equal to the Bragg angle. Typical breaks in the diffuse scattering intensity due to the standing-wave effect are absent, and there is obvious asymmetry of the diffuse scattering cross section around the incoming and outgoing angles. Due to the small angle of incidence, the coherently irradiated area has very different dimensions parallel and perpendicular to the beam, which leads to the observed scattering being concentrated in the specular diffraction plane defined by the incident and reflected wave vectors. [ABSTRACT FROM AUTHOR]

The techniques of X-ray fluorescence analysis with synchrotron radiation (SRXRF) use mainly the external standard method, which imposes an essential requirement of similarity of absorption and scattering of the primary and fluorescence radiation by the matrices of the test sample and the reference one. In this connection, there is an actual problem of shortage or absence of required standard reference samples. In this paper we consider a variant of analysis of a biological tissue (certified reference material NCSZC 85005 Beef liver) with a standard sample of geological matrix (certified reference material IAEA Soil-7) as a reference sample. The concentrations of K, Ca, Mn, Fe, Cu, Zn, Br, Rb and Sr were determined in the standard liver sample with and without allowance for fluorescence radiation absorption by the differing matrices. Using the absorption correction enabled full account of the difference in the absorption properties of the matrices under study (liver and soil) and obtaining chemical element concentrations having no significant difference from certified values. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: A record low horizontal emittance of 1 nm-rad was successfully obtained in PETRA III third generation synchrotron light source. A key system that allowed reaching such value includes 20 permanent magnet damping wigglers installed in two long straight sections. The wigglers radiate almost 1 MW at maximum current of hard X-ray radiation which issues a challenge for the design of SR absorbers and vacuum system components for the damping wiggler section. The paper describes in detail the design consideration, manufacturing and experimental performance of absorbers and vacuum system. The first experimental results of PETRA III damping wiggler section operation are presented. [Copyright &y& Elsevier]