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The internal structure of an olivine‐rich fragment of the Seymchan meteorite was studied using neutron tomography. The differences in the neutron attenuation coefficients of constituent elements of the studied pallasite and the application of modern mathematical algorithms for a three‐dimensional (3‐D) imaging data analysis allow us to obtain a spatial distribution of different meteorite components. The heterogeneous distribution of the nickel in the metal phase was observed. In addition to the resulting 3‐D model of the Seymchan meteorite, the distributions of the volumes, average sizes, and shape‐related parameters of the FeNi metal component and olivine grains were obtained.

The itinerant electron metamagnetism (IEM) is an essential physical concept, describing magnetic properties of rare earth – transition metal (R-TM) intermetallics, demonstrating technologically important giant magnetoresistance and magnetocaloric effects. It considers an appearance of TM magnetization induced by spontaneous magnetization of surrounding R atoms, which provides significant response of the magnetic and transport properties on variation of external parameters (temperature, pressure, magnetic field) due to strong coupling between magnetic sublattices. The RCo2 compounds were generally considered as model systems for understanding of basic properties of IEM intermetallics. However, microscopic nature of magnetic properties still remains unclear. In our experimental and theoretical study of ErCo2 in a wide range of thermodynamic parameters a sequential collapse of cobalt sublattice magnetization in the background of nearly unchanged Er sublattice magnetization was revealed. The uncoupled magnetizations behavior challenges the IEM concept applicability and evidences more complex nature of magnetism in ErCo2 and related RCo2 systems.

A neutron radiography and tomography facility have been developed recently at the IBR-2 high flux pulsed reactor. The facility is operated with the CCD-camera based detector having maximal field of view of 20x20 cm, and the L/D ratio can be varied in the range 200 -2000. The first results of the radiography and tomography experiments with industrial materials and products, paleontological and geophysical objects, meteorites, are presented.

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