[en] Plasma properties in pulsar magnetosphere are considered in detail as well as state of art of their radio emission theory is reviewed. Dielectric constant tensor of relativistic plasma moving along force lines of curvilinear magnetic field has been determined. It is shown that in case of sufficiently high plasma density hydrodynamic instability leading to rapid growth of two normal modes of electromagnetic oscillations named plasma bending is excited. Concrete conditions in the pulsar - magnetosphere is considered. It is also shown that rapid swinging of plasma-bending modes occurs in the near magnetosphere region. At (30-300)R distance from a neutron star these oscillations are transformed to common radio emission directed along magnetic field force lines

[en] The new ROE/ESO large-scale AQD survey for quasars forms a connected area of approx. 200 deg² near the South Galactic Pole, and has resulted in the discovery of a total number of quasar candidates that is comparable to the number previously published from all other sources. This paper describes a three-dimensional clustering analysis of approx. 1100 'high-probability' candidates occupying the assigned-redshift band of 1.8-2.4. The analysis is sensitive to very weak clustering - to a level of 7 per cent of the quasars occurring in pairs on scales approx. 5h^-1 Mpc - but none is found. (author)

[en] Using a multichannel polarimeter at 10 GHz attached to the 45-m radio telescope at Nobeyama, the authors have observed about 100 extragalactic radio sources which were suspected to have large rotation. Four of these 100 sources were found to have an intrinsic rotation measure > 1,000 rad m^-2. Rotation measures are reported which are two orders of magnitude larger than those observed so far for most extragalactic radio sources. Two of these four sources are classified as compact steep-spectrum sources. (author)

[en] Letter to the editor

[en] A rough spectral analysis of the primary component of β Lyr is presented and a total of 122 spectral lines are identified in the optical region 3700 A - 6750 A. The equivalent widths for 92 of them are measured and radial velocities for a number of lines computed. The identification revealed very strong He I lines and apparently enhanced N II lines, and also raised some controversial questions concerning the strongest C II line in the visible, namely C II 4267 A. (author). 3 figs., 2 tabs., 21 refs

[en] The ratio R of early- to late-type luminous stars in young populous globular clusters in the Magellanic Clouds has been obtained via spectral classification. It was found that there are very young globular clusters (age 10⁷ - 5 x 10⁷ yr) with a high percentage of hot stars. This kind of stellar system is not observed in our Galaxy. The observed ratios R for the LMC clusters exhibit values larger than those found for the SMC, indicating that the hot stars in the SMC clusters are fewer. This has been attributed to the longer lifetimes of the late type supergiants because of lower heavy element abundances or lower mass loss rates. (author)

[en] The Brackett alpha and beta lines with 7.2 seconds angular and 350 km/s velocity resolution were observed in 11 infrared-bright galaxies. From these measurements extinctions, Lyman continuum fluxes, and luminosities due to OB stars were derived. The galaxies observed to date are NGC3690, M38, NGC 5195, Arp 220, NGC 520, NGC660, NGC1614, NGC 3079, NGC 6946, NGC 7714, and Maffei 2, all of which were suggested at some time to be starburst ogjects. The contributions of OB stars to the luminosities of these galaxies can be quantified from the measurements and range from insignificant to sufficient to account for the total energy output. The OB stellar luminosities observed are as high as 10 to the 12th solar luminosities in the galaxy NGC 1614. It is noteworthy that star formation can play very different roles in the infrared energy output of galaxies of similar luminosity, as for example Arp 220 and NGC 1614. In addition to probing the star formation process in these galaxies, the Brackett line measurements, when compared to radio and infrared continuum results, have revealed some unexpected and at present imperfectly understood phenomena: in some very luminous sources the radio continuum appears to be suppressed relative to the infrared recombination lines; in many galaxies there is a substantial excess of 10 micron flux over that predicted from simple models of Lyman alpha heating of dust if young stars are the only significant energy source

[en] The source of the halo about M82 has been under discussion for several years. One explanation for it is the dust model of Solinger, Morrison and Markert in which they propose a diffuse cloud of dust through the M81 group, with M82 traveling through the group holding a denser cloud of dust around it. The feasibility of the dust theory is examined in the x-ray range, using the halo in the x-ray image of M82 taken by the Einstein Observatory. To this end the x-ray cross section for dust is presented, along with the single scattered image of an x-ray source surrounded by a dust cloud; multiply scattered images were simulated with a Monte Carlo program; profiles of the halo along the major and minor axes of M82 are presented. Also presented is an accounting for line spectrographs of M82 that show unusual splitting, using the dust model. The final model proposed for the X-ray image requires dust of radius 50 to 300 A, with density on the order of 10 to the -7th power cu cm, out to a distance of about 9 kpc for some regions

[en] A very tight correlation was found between the radio emission and the far infrared emission from galaxies. This has been found for various samples of galaxies and is explained in terms of recent star formation. The tight correlation would imply that the total radio emission is a good tracer of star formation. The correlation between the radio power at 5 GHz and the far infrared luminosity is shown. The galaxies are of various morphological types and were selected from the various IRAS circulars, hence the sample is an infrared selected sample. The far infrared luminosities were corrected for the dust temperature. This is significant because it decreases the dispersion in the correlation

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