This is the second in a series of papers presenting a new calculation of the mass of the Galaxy based on radial velocities and distances for a sample of faint 16<B<21.3 field blue horizontal-branch (BHB) stars. We present accurate BV CCD photometry and spectra for 142 candidate A-type stars selected from ubjr photometry of UK Schmidt telescope plates in six high-Galactic-latitude fields. Classification of these candidates produces a sample of 60 BHB stars at distances of 11-52kpc from the Sun (mean 28kpc), with heliocentric line-of-sight velocities accurate to 15km/s, and distance errors <10 per cent. We provide a summary table listing coordinates and velocities of these stars.
We present wide-area UBRI photometry for globular clusters around the Leo group galaxy NGC 3379. Globular cluster candidates are selected from their B-band magnitudes and their (U-B)_0_ versus (B-I)_0_ colours. A colour-colour selection region was defined from photometry of the Milky Way and M31 globular cluster systems. We detect 133 globular cluster candidates, which supports previous claims of a low specific frequency for NGC 3379.
We present UBRI photometry and spectra for 60 quasars found within 1{deg}^2^ centered on the J0053+1234 region, which has been the subject of the Caltech Faint Galaxy Redshift Survey. Candidate quasars were selected by their ultraviolet excess with respect to the stellar locus and confirmed spectroscopically. The quasars span a wide range in brightness (17.5<B<21.6) and redshift (0.43<z<2.38).
We describe a new estimate of the radio galaxy 1.4 GHz luminosity function and its evolution at intermediate redshifts (z~0.4). Photometric redshifts and color selection have been used to select B_J_<23.5 early-type galaxies from the Panoramic Deep Fields, a multicolor survey of two 25deg^2^ fields. Approximately 230 radio galaxies have then been selected by matching early-type galaxies with NVSS radio sources brighter than 5mJy. Estimates of the 1.4GHz luminosity function of radio galaxies measure significant evolution over the observed redshift range. For an {Omega}_M_=1 cosmology the evolution of the radio power is consistent with luminosity evolution where P(z)~P(0)(1+z)^K_L_^ and 3<K_L_<5. The observed evolution is similar to that observed for UVX and X-ray selected active galactic nuclei and is consistent with the same physical process being responsible for the optical and radio luminosity evolution of active galactic nuclei.
We have obtained U,B, and R CCD surface photometry for a sample of 39 elliptical galaxies. For each galaxy we have determined the surface brightness profile, U-R and B-R color profiles, and the ellipticity and position angle profiles, all as function of major axis radius, using a two-dimensional ellipse fitting program. In addition, we have derived the sin and cos(3.theta) and 4.theta terms that describe the high-order deviations of the B and R isophotes from ellipses. While it is very common for ellipticals to display measurable 3.theta and 4.theta terms, the amplitudes of these terms rarely exceed 0.5%. The isophotes of elliptical galaxies are very well characterized by ellipses. The surface brightness and color profiles are given to radii at which the error in the profile reaches 0.1 mag from the uncertainty in the brightness of the night sky. We have carried out a series of simulations of the effects of seeing on luminosity and ellipticity profiles, to determine the radius beyond which the errors in our data from seeing are less than 0.05 mag and 0.02 in ellipticity. Measurable effects of seeing extend to surprisingly large radii, as much as 5-10 seeing radii, depending upon the ellipticity of the galaxy and the form of the surface brightness profile. Ellipticity and position angle profiles are usually the same in all passbands with no indication that the contours of constant color are more or less flattened than the isophotes, i.e., the isochromes and isophotes have the same shapes, but the insensitivity of the ellipticity to differences between these properties makes this a weak argument. The high-order terms, particularly the 3.theta terms, appear to be sensitive diagnostics for the existence of dust in ellipticals. We find that all the galaxies in this sample either become bluer in B-R and U-R with increasing radius or are of constant color. Mean values for the logarithmic gradients in color are -0.09 mag/arcsec2 per dex in radius in B-R, and -0.20 mag/arcsec2 per dex in radius in U-R. These color changes are consistent with a decrease in the [Fe/H] of approximately 0.20 per decade in radius. Surprisingly, there is no correlation of color gradient with luminosity. It is striking, however, that the lowest luminosity galaxies in the sample (i.e., those with M(B) > -20) do not show any color gradients. They have boxy isophotes, and are also rotationally flattened. While these properties may be related to the fact that they are companions of larger ellipsoidal systems, it could provide an important clue to the formation of ellipticals. Low luminosity ellipticals that are not close companions to giant ellipticals need to be studied.
Results of photoelectric UBVRI photometry of 78 stars and photographic PDS and CCD photometry for 437 stars are presented for Collinder 110, an old open cluster at low Galactic latitude. Proper motions obtained from Lick Sky Survey plates were used to identify 39 stars as foreground objects. The cluster's reddening, distance, and age are estimated as E(B-V)=0.50+/-0.03mag, r=1950+/-300pc, and t=1.4+/-0.3Gyr, assuming a solar metal abundance.
As part of a thorough study of the luminosity function of Sco-Cen, UBV, and H_{beta}_ photometry has been acquired for a large number of mid B- to late A-type stars which are within or surrounding the Scorpius-Centaurus OB association. UBV and H_{beta}_ photoelectric measures have been obtained for all the B stars without previous observations and for many of those with in the large field 280deg<=l<=362deg, +10deg<=b<=+40deg, and m-M<=7.5mag. Within the upper Scopius subgroup (ScoOB2), 341deg<=l<=362deg, +10=<b=<30deg, UBV and H_{beta}_ photometry was obtained for all B stars listed in the MSC(HD) catalog. As well, UBV measures were obtained for all the A-type stars within this field.
Photoelectric and spectroscopic observations of the protoplanetary object V1853 Cyg, a B supergiant with an IR excess, are given. The observations were carried out with a UBV photometer attached to the 60-cm Zeiss telescope at the Crimean Station of the Stenberg Astronomical Institute.
We present a proper-motion, CCD photometric study of stars in the distant halo globular cluster Palomar 13. The absolute proper motion of Pal 13 with respect to the background galaxies, derived from moderate-scale photographic plates separated by a 40 year baseline, is (pmRAcosDE, pmDE)=(2.30, 0.27)+/-(0.26, 0.25)mas/yr.
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