Medium polarization dynamics with atomic cluster formation in radioactive lutetium oxide

Full text: The study of processes in a material of a radioactive sources was begun by us in connection with our work directed to the accuracy increase of electron-spectroscopy researches of nucleus decays. It was necessary to draw large attention to the form of electronic spectra and separate conversion lines, their dynamics and to research explanations of their anomalies with use for this purpose not only nuclear-spectroscopy methods, but also opportunities of auto-emission and Auger-spectroscopy. The analysis of all experimental results of our long-time research (∼ 13 years) of the radioactive lutetium oxide, deposited on a platinum support, as a radioactive source, has resulted us in the following assumptions of processes occurring in the source material. The lutetium oxide is a dielectric, having spontaneous polarization varying in the radiation field of the radioactive decay. The polarization is determined by domains - areas with various directions of polarization. Under action of an electrical field the volumes of the polarized along the field domains are increased at the expense of the ones, polarized against the field. The domain borders fixed on inhomogeneities move, for example, under action of internal conversion electrons accompanying the decay of radioactive nuclei. The experimentally observable energy losses of such electrons achieve 500 eV. In the cluster formation process the multipole character of nucleus decay electron radiation causing transfer of the angular moment by the electrons to atoms with collision with them plays a significant role. The auto-emission and Auger-spectra specify a determining role of the M4- and M5-subshells of ytterbium atoms in the cluster formation. It is possible to assume, that in the lutetium oxide electrical dipole medium at first the metal ytterbium clusters are formed. Their valent electrons are not located in space and are conducting electrons, for example, the electrons of the destroyed N-shell. It is possible to present the nature of the forces connecting atoms in metal clusters as interaction between dipoles (an electron - a positively charged ion). The tightening of domains with different directions of their polarization concerning the field causes rapprochement of the clusters, and subsequently - their insularity, mother words, gives them the toroid form. We come to the following conclusion: there is the opportunity of study by the specified above methods of the atomic cluster formation phenomenon in thin films, its dynamics, structure and sizes of fields formed local and phase transitions of the second sort with change both spatial, and magnetic and electrical symmetries. The internal conversion electrons accompanying the decay of the Lu isotopes used in the given work have the wave lengths in the 10-9-10-10 cm range are sensitive to local heterogeneities in the rather wide interval of their sizes. The clear displays in the internal conversion electron spectrum of features caused by their interference, the Doppler broadening of lines, satellite lines of polarized electrons, channeled in space a nucleus-electron shell of the atom of deformed by connections with shells of other atoms of the cluster testified to it. The complex dynamics of the form and intensity of electron lines is caused, in particular, by the medium domain structure destruction on reaching of the limit value of the electrical potential gradient throughout the radioactive layer thickness and by subsequent recurrences of such cycles with the appropriate increase of the time intervals, necessary for their realization. The discussed experimental data collection points to the opportunity of study of the paraelectric-ferroelectric (and on the contrary) type phase transition and complex dynamics of electrical, magnetic and toroidal polarization of condensed medium by some untraditional methods