122 research outputs found
On Generalized Bose-Einstein Condensation in the Almost-Ideal Boson Gas
We scrutinize an interparticle interaction which can create the type-I generalized Bose-Einstein condensation in spite of other thermodynamic properties of the model coinciding with those for the free boson gas
Implementation of a double-scanning technique for studies of the Hanle effect in Rubidium vapor
We have studied the resonance fluorescence of a room-temperature rubidium
vapor exited to the atomic 5P3/2 state (D2 line) by powerful single-frequency
cw laser radiation (1.25 W/cm^2) in the presence of a magnetic field. In these
studies, the slow, linear scanning of the laser frequency across the hyperfine
transitions of the D2 line is combined with a fast linear scanning of the
applied magnetic field, which allows us to record frequency-dependent Hanle
resonances from all the groups of hyperfine transitions including V- and Lambda
- type systems. Rate equations were used to simulate fluorescence signals for
85Rb due to circularly polarized exciting laser radiation with different mean
frequency values and laser intensity values. The simulation show a dependance
of the fluorescence on the magnetic field. The Doppler effect was taken into
account by averaging the calculated signals over different velocity groups.
Theoretical calculations give a width of the signal peak in good agreement with
experiment
Comparison of the Effects of Electrolytic and Chemical Destruction of the Red Nucleus on the Compensatory Capacity of Rats With Rubrospinal Tract Lesions
Transection of the rubrospinal tract in rats, performed before lesion of the red nucleus, resulted in the facilitated recovery of motor
activity and operantly conditioned reflexes. Such facilitation was absent when the red nucleus is lesioned alone. This phenomenon is
explained by the switching of descending influences on the corticospinal tract through the participation of the following system: red nucleusâinferior oliveâcerebellumâventrolateral thalamic nucleusâcerebral cortex. The above mentioned facilitating influence on the recovery process was particularly prominent in rats with quinolinic acid-induced lesion of the red nucleus. Under these conditions, the cerebellar ascending fibers to the ventrolateral thalamic nucleus were preserved. Decreased facilitated recovery following electrolytic lesion of the red nucleus suggests the existence of additional cerebello-cortical pathways for the realization of the switching phenomenon
Abelian Sandpile Model on the Husimi Lattice of Square Plaquettes
An Abelian sandpile model is considered on the Husimi lattice of square
plaquettes. Exact expressions for the distribution of height probabilities in
the Self-Organized Critical state are derived. The two-point correlation
function for the sites deep inside the Husimi lattice is calculated exactly.Comment: 12 pages, LaTeX, source files and some additional information
available at http://thsun1.jinr.dubna.su/~shcher
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