[1] A unified theory of the mirror instability in space plasmas is developed. In the standard quasi-hydrodynamic approach, the most general mirror-mode dispersion relation is derived and the growth rate of the mirror instability is obtained in terms of arbitrary electron and ion velocity distribution functions. Finite electron temperature effects and arbitrary electron temperature anisotropies are included. The new dispersion relation allows the treatment of more general space plasma equilibria such as the Dory-GuestHarris (DGH) or Kennel-Ashour-Abdalla (KA) loss cone equilibria, as well as distributions with power law velocity dependence that are modeled by the family of k-distributions. Under these conditions, we derive the general kinetic mirror instability growth rate including finite electron temperature effects. As for an example of equilibrium particle distribution, we analyze a large class of k to suprathermal loss cone distributions in view of application to a variety of space plasmas like the solar wind, magnetosheath, ring current plasma, and the magnetospheres of other planets.

The excitation of a helicon plasma source by an azimuthally symmetric antenna is considered in comparison with anti-symmetric excitation. The resonances and anti-resonances at the wave excitation, as well as the peculiarities of the power absorption, are shown to be very similar for symmetric and anti-symmetric excitation. The plasma resistance turns out to be higher in the case of symmetric excitation for very short devices. The non-monotonic variation of plasma resistance with density is found to be intrinsic for both methods of excitation as a result of decreasing the power absorption at anti-resonances. This is shown to give rise to abrupt density jumps at varying input power.

Abstract. The theory of ionospheric Alfv6n resonator (IAR) and IAR feedback instability is reconsidered. Using a. simplified model of the topside ionosphere, we have reanalyzed the physical properties of the IAR interaction with magnetospheric convective flow. It is found tha, t in the absence of the convective flow the IAR eigenmodes exhibit a strong da, mping due to the leakage of the wa,ve energy through the resonator upper wall and Joule dissipation in the conductive ionosphere. It is found that maximum of the dissipation rate appears when the ionospheric conductivity approaches the "IAR wave conductivity" and becomes infinite. However, the presence of Hall dispersion, associated with the coupling of Alfv•n wave modes with the compressional perturbations, reduces the infinite damping of the IAR eigenmodes in this region and makes it dependent on the wavelength. The increase in the convection electric field lea, ds to a. substantial modification of the IAR eigenmode frequencies a. nd to reduction of the eigenmode damping rates. For a given perpendicular wa,velength the position of inaximum damping rate shifts to the region with lower ionospheric conductivity. When the convection electric field approaches a certain critical va,lue, the resona,tor becomes unstable. This results in the IAR feedback instability. A new type of the IAR feedba, ck instability with the lowest threshold value of convection velocity is found. The physica,1 mecha, nism of this instability is similar to the Cerenkov radiation in collisionless plasma,s. The favorable conditions for the insta, bility onset are realized when the ionospheric conductivity is low, i.e., for the nighttime conditions. We found that the lowest value of the marginal electric field which is ca, pa, ble to trigger the feedback instability turns out to be nearly twice smaller tha, n tha,t predicted by the previous analysis. This effect may result in the decrease of the critical value of the electric field of the magnetospheric convection tha,t is necessary for the forma, tion of the turbulent Alfv•n boundary layer and appearance of the a, nomalous conductivity in the IAR region.

We studied peculiarities of the spectral characteristics of EEG in 111 healthy adult subjects of both sexes. The levels of situative anxiety (anxiety state) and personal anxiety were estimated using the Spielberger-Khanin test system. To estimate anxiety-related properties of the personality, Cattel's technique 16 PF (form А) was used. Estimates of situative anxiety demonstrated only two cases of positive correlation with the spectral power density (SPD) of EEG rhythms (SPDs of the beta2 rhythm in the right-hemisphere temporal and occipital regions; recording with the eyes open). Estimates of personal anxiety positively correlated with the SPDs of the beta1 and (especially) beta2 EEG rhythms. Under conditions with the eyes open, the number of significant correlations was greater, and correlations themselves were tighter than with the eyes closed. The closest correlations of the estimates of personal anxiety with the SPDs of the beta rhythm were found in frontal and central leads of both hemispheres and in parietal and occipital loci of the right hemisphere. Only a single case of correlation of the alpha rhythm SPD with personal anxiety (negative correlation, a parietal lead in the left hemisphere) was found. At the same time, rather numerous correlations of the alpha rhythm expression with an index congeneric to anxiety, the C factor by the Cattel's questionnaire (emotional stability/instability), were found. Thus, the intense beta EEG rhythm can be considered an electrographic correlate of high situative and personal anxieties. At the same time, the alpha rhythm power correlates with the emotional stability of the individual. We suppose that persons with a well-developed alpha rhythm are characterized by active and stable functioning of the cerebral dopaminergic system; this simultaneously serves as a pre-requisite of high emotional stability and social adaptability.

Abstract. Linear theory of the drift-mirror instability in high-/• plasma is reconsidered referring to basic principles for the two cases of a one-and a twocomponent ion plasma in presence of a cold electron background. In both cases the cold electrons serve to shortcut the parallel electric field component which imposes the condition of vanishing the field-aligned current. The corresponding low-frequency dispersion relation is derived in the fluid approximation as well as from kinetic theory including nonvanishing gradients in the density. The free energy of the unstable mode is taken from two sources: the pressure anisotropy and the spatial inhomogeneity of the plasma. The dispersion relation contains a correction which originates from the inclusion of the bending of the magnetic field that is caused by the reaction of the field to the total pressure force. It is shown that the mirror force substantially reduces the phase velocity which is in favour of instability since this requires phase velocities less than the drift speed. The direction of phase velocity becomes antiparallel to that of the pure density-gradient drift velocity. Even for a. mirror-stable plasma an instability arises which is solely due to inhomogeneity. We ana, lyze the transition to the classical mirror instability.Application to ring current (hot ring current ions plus cold plasmasphere ions) and magnetosheath (hot sheath ions only) conditions is presented and is in agreement with observational indication of the apparent stability of the pure mirror mode in the ring current. comets, and in the solar wind. In the high-/3 plasma of the solar wind and the magnetosheath, mirror modes