The Kharkov X-ray Generator Facility NESTOR

WEPWA060 - ISBN 978-3-95450-122-9International audienceThe last few years the sources of the X-rays NESTOR based on a storage ring with low beam energy and Compton scattering of intense laser beam are under design and development in NSC KIPT. The main task of the project is to develop compact intense X-ray generator on the base of relatively cheap accelerator equipment and up-to-date laser technologies. The paper is devoted to description of the last results on construction and commissioning of the facility

Experimental study of the magnetic characteristics of nanocrystalline thin films: the role of edge effects

Magnetic characteristics and their spatial distribution of magnetron sputtered nanocrystalline NiFe thin films of various compositions were investigated by ferromagnetic resonance (FMR) and magneto-optical Kerr effect microscopy. A sharp increase in the FMR linewidth and a strong deviation of the uniaxial magnetic anisotropy field were observed near the film edges. It was shown that the observed magnetic anisotropy behavior can be explained by assuming that besides the field-induced uniaxial magnetic anisotropy an additional source of the uniaxial anisotropy near the film edges exists, with the easy axis parallel to the edges. The possible origins of this additional contribution were discussed

A magnetometer of weak quasi-stationary and high-frequency fields on resonator microstrip transducers with thin magnetic fields

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.A high-sensitivity magnetometer for simultaneous measurements of three components of a weak quasi-stationary or high-frequency magnetic-field vector was developed and investigated. Microstrip structures that are based on irregular resonators serve as the magnetometer transducers. An anisotropic thin-film magnetic structure is used as the sensing element. This structure consists of two thin magnetic films that are prepared by magnetron sputtering of a Ni75Fe25 permalloy target and separated by a silicon monoxide layer. It is demonstrated that the transducer exhibits the maximum sensitivity, when the easy magnetization axis of the film structure is orthogonal to the polarization direction of the pumping microwave magnetic field in the microstrip resonator and at an optimal value of a constant magnetic bias field and its optimal deflection from the pumping-field polarization direction which is parallel to it. The magnetometer is characterized by a wide dynamic range of measured magnetic fields, 10(-10)-10(-4) D cent, and a wide frequency range, 10(-1)-10(5) Hz

Crystal structure and lattice dynamics of superionic copper selenide Cu 2-delta Se

The crystal structure and lattice dynamics of copper selenide were studied in the superionic (alpha) and the non-superionic beta-phase. X-ray and neutron powder diffraction confirmed space group Fm3m for Cu1.78Se with Cu atoms mainly in the tetrahedral 8(c) sites and a small fraction in trigonal 32(f) sites. Inelastic neutron scattering in polycrystalline alpha-Cu1.78Se and beta-Cu2Se samples indicate the presence of a broad quasi-elastic component and low-energy peaks in the dynamic structure factor S(Q,omega). The quasi-elastic component is related to localised diffusion of Cu ions in the 32(f) sites. The low-energy modes observed in Cu, Se and Cu,Se at energies of 4-5 meV are most probably due to acoustic phonons. The phonon dispersion curves measured in alpha-Cu1.85Se single crystal reveal the existence of low-lying acoustic transversal branches with no marked dispersion at wavevectors higher than 0.3-0.4 q/q(m) with an energy of about 4 meV. (C) 2003 Elsevier B.V. All rights reserved

A magnetometer of weak quasi-stationary and high-frequency fields on resonator microstrip transducers with thin magnetic fields

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.A high-sensitivity magnetometer for simultaneous measurements of three components of a weak quasi-stationary or high-frequency magnetic-field vector was developed and investigated. Microstrip structures that are based on irregular resonators serve as the magnetometer transducers. An anisotropic thin-film magnetic structure is used as the sensing element. This structure consists of two thin magnetic films that are prepared by magnetron sputtering of a Ni75Fe25 permalloy target and separated by a silicon monoxide layer. It is demonstrated that the transducer exhibits the maximum sensitivity, when the easy magnetization axis of the film structure is orthogonal to the polarization direction of the pumping microwave magnetic field in the microstrip resonator and at an optimal value of a constant magnetic bias field and its optimal deflection from the pumping-field polarization direction which is parallel to it. The magnetometer is characterized by a wide dynamic range of measured magnetic fields, 10(-10)-10(-4) D cent, and a wide frequency range, 10(-1)-10(5) Hz