General track of pulsar evolution

It is shown that large mulling, small luminosity and a large value of polarization angle variation are, together, a good indication of a pulsar's old age. Selection effects connected with the discovery of pulsars are analyzed. The general track of pulsar evolution, along which the diagram of pulsar emission and the angle between the magnetic and rotation axes decrease, is found.     

Σ(D)-dependence of SNR in a cloudy interstellar medium and regularZ-effect

Critical analysis of the earlier obtained Σ(D)-dependences in the light of new observational data on the interaction of SNR expanding envelopes with inhomogeneities of interstellar medium is carried out. It is shown that more correct consideration of the factors which are the basis ofZ-effect introduction testifies to the dominating role of interstellar medium cloudiness, which completely suppresses the influence of the regular component of the medium. On the basis of most reliable calibrators and on the last observations, theoretical notions of evolution, new Σ(D)-dependence for shell type SNR in a cloudy interstellar medium is obtained. On the basis of this dependence diametersD, distances from the Sund and height over the galactic planeZ for ～100 shell type SNR at two frequencies, 408 MHz and 1 GHz are calculated.     

Electrical properties of some magmatic dike rocks at high temperatures

The electrical properties of magmatic rocks (diabase and granite porphyry) from the complex dike located in the Main Caucasian (Akhtychaisk) fault zone are examined at temperatures of 100?C1000°C. It is established that the increase in the electrical conductivity from granite porphyry to diabase is caused by the decreased quartz content, increased total content of iron oxides FeO and Fe₂O₃, as well as the fine-grained texture of diabases and their secondary alterations. The pattern of temperature dependence of specific electrical conductivity observed in granite porphyry and diabases reflects the polymorphic transformation of the monoclinic structure to the triclinic structure (the MT-transformation), which occurs in the feldspar component of the rock. Another factor responsible for the shape of the mentioned temperature dependence is that the formation of an extrinsic mechanism of conduction is dominated by the defects (associated into complexes) in the crystal lattices of the minerals. This allows determining the energy of formation and migration of lattice defects and the energy of association of the lattice defects into complexes, which play an important role in the natural metamorphic processes. The AC measurements for the granite porphyry revealed frequency dispersion of the electrical conductivity, which decreases with increasing temperature.     

He-rich white dwarfs: Birth-rate and kinematics of different groups of white dwarfs

The temperatures, radii, and masses of 81 He-rich white dwarfs are calculated from photometric data. It is shown that, on the average, they are less massive than DA white dwarfs: 70% of He-rich white dwarfs have masses<0.55M _⊙. Space density and birth-rate for different mass groups of H-rich and He-rich white dwarfs are obtained. Birth-rate is 1×10^?12 pc^?3 yr^?1 and 1.5×10^?12pc^?3yr^?1 for He-rich and H-rich white dwarfs, respectively. The mean mass of nascent white dwarfs is about 0.55M _⊙. It is shown thatV _Tand its dispersion σ are correlated with the mass of white dwars, and from this progenitors' masses — of different mass groups of white dwarfs are estimated.     

The spatial distribution and birth-rate of pulsars

The distribution of pulsars in the wide range of observed luminosities has been obtained. It is shown that the function of luminosity (FL) within 3×10²⁶L2×10³⁰ erg s^–1 conforms to the power law dN/dL–c ₁ L ^–, where =1.76±0.06. ForL3×10²⁶ erg s^–1, FL changes its inclination and may be approximated as , where ₁ = 0.7±0.2. On the basis of statistical selection, including all pulsars withL>3×10²⁸ erg s^–1, the distribution of pulsars has been investigated as a function of the distance to the centreR and galactic planeZ.The obtained laws of the radial andZ-distribution of pulsars and galactic supernova remnants and also the radial distribution of types I and II supernovae in the models Sb and Sc support the hypothesis of their origin from the objects of the flat subsystem of Population I. Since there are some arguments in favour of a possible connection between supernovae I and the objects of the intermediate component of the Galaxy, one cannot exclude the possibility of supernovae explosions at the end of the evolution of stars with masses of 1.5–2M . It is also shown that pulsars and supernovae are evidently objects that are connected genetically, and, within the limits of statistical error, they have a similar birth-rate.The empirical law of the evolution of a pulsar's luminosity as a function of its true age has been obtained, according to whichL=c ₂ t ^–, wherec ₂=(3.69±3.4)×10³⁵, =1.32±0.11.     

The evolution of supernova remnants

The observational data analysis is based on the selection of 14 shell-type SNR, whose distances are quite reliable. Parameters of those SNR characterizing the values of the mean electron densityn _e, the change ofk ^2/7 H and velocity of expansionV are taken. The other parameters of SNR, such as energy of explosion, energy in magnetic field, and relativistic particles, and its increase during the expansion of SNR, are taken and analysed.