No abstract available

[en] uvby photometry and WULBV (Walraven) photometry for 50 F stars down to V=11.8 in the McCormick proper motion fields near the south galactic pole are discussed with emphasis on the metal abundance parameter. It is shown that quantities delta(B-L) can serve well to measure metal abundance as an equivalent to deltam₁. The distribution of deltam₁ is shown for distances z=300 to 600 pc, bearing over the intermediate population II character of this sample. (Auth.)

[en] We present the results of detailed CCD surface photometry of a sample of ten early-type barred galaxies. The observations were made in three colors (B Johnson, I and R Kron-Cousins bandpasses). We display surface brightness, ellipticity and position-angle profiles for each galaxy, obtained by fitting ellipses to the isophotes. Various parameters, like bar length, angle of inclination on the plane of the sky, etc..., are determined. We also discuss the accuracy of ellipse-fitting in the bar region where the isophotes are more rectangular than they are in elliptical galaxies

[en] The external accuracy of photometric parameters of asteroids is investigated by a comparison of published lists. Absolute magnitudes are consistent at the ±0.1 mag level but phase coefficients are still rather uncertain. (author). 1 fig., 1 tab., 5 refs

No abstract available

[en] UBVRI photoelectric observations are presented for the Population II cepheid V553 Cen. Its period of 2.06051d is confirmed. (U.S.)

[en] The data on 37 asteroids obtained with the Calsberg Automatic Meridian Circle at La Palma have been used to obtain the photometric parameters G and H and to draw phase diagrams. This supplements data on 51 asteroids and on 31 asteroids using the same techniques. Synodic periods were obtained for 6 asteroids and composite lightcurves drawn. For 10 Hygiea our value of 17.5 hours is different from that of Vesely and Taylor (1985) but in agreement with the result reported by Harris and Young (1983). 24 asteroids were of type S and the mean value of 0.19 agrees very well with that of Lagerkvist and Williams (1987) and Lagerkvist et al. (1988). For the 6 asteroids of type C we get a mean G value of 0.04 agreeing well with earlier results

[en] During the years 1985-1989 photographic monitoring of 12 blazars has been in progress at Turku University Observatory. The results of 208 observations are presented. Our main objects have been 0735 + 178, 0754 + 100, BL Lac and especially OJ 287 which was observed 64 times during these years

[en] After a review of the temporal properties of photomultipliers used in single photoelectron experiments, the main problems encountered in the applications to measurement of the shape of fast light pulses and to the determination of the statistical characteristics of light beams are examined

[en] A test has been made of the reliability of the multidimensional classification of late-type stars from low-dispersion objective-prism plates recently attempted by Stock and Wroblewski. Such classification at low dispersion is difficult due to the problem of separating the effects of luminosity from those of abnormal metal abundance. A sample of the stars classified by Stock and Wroblewski as metal weak (pec) and of those classified as luminous stars (class I) were observed using the DDO intermediate-band photometric system. The photometry shows that the stars classified as pec are indeed Population II giants of low metal abundance ([Fe/H] <-1.0). The stars classified as I, however, were found in general not to be true supergiants but rather a mixture of various types of giants, such as CN strong stars, with spectral features that resemble, in one way or another, those of higher luminosity stars