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|Arcsecond Positions of UGC Galaxies|
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.
|The Dynamics of Poor Systems of Galaxies|
We assemble and observe a sample of poor galaxy systems that is suitablefor testing N-body simulations of hierarchical clustering and otherdynamical halo models. We (1) determine the parameters of the densityprofile rho(r) and the velocity dispersion profile sigma_p(R), (2)separate emission-line galaxies from absorption-line galaxies, examiningthe model parameters and as a function of spectroscopic type, and (3)for the best-behaved subsample, constrain the velocity anisotropyparameter, beta, which determines the shapes of the galaxy orbits. Oursample consists of 20 systems, 12 of which have extended X-ray emissionin the ROSAT All-Sky Survey. We measure the 877 optical spectra ofgalaxies brighter than m_R~15.4 within 1.5 h^-1 Mpc of the systemcenters (we take H_0=100 h km s^-1 Mpc^-1). Thus, we sample the systemmembership to a radius typically three times larger than other recentoptical group surveys. The average system population is 30 galaxies, andthe average line-of-sight velocity dispersion is ~300 km s^-1. TheNavarro, Frenk, & White universal profile and the Hernquist modelboth provide good descriptions of the spatial data. In most cases anisothermal sphere is ruled out. Systems with declining sigma_p(R) arewell-matched by theoretical profiles in which the star-forming galaxieshave predominantly radial orbits (beta>0) many of these galaxies areprobably falling in for the first time. There is significant evidencefor spatial segregation of the spectroscopic classes regardless ofsigma_p(R).
|The First Bright QSO Survey|
The FIRST radio survey provides a new resource for constructing a largequasar sample. With source positions accurate to better than 1" and apoint source sensitivity limit of 1 mJy, it reaches 50 times deeper thanprevious radio catalogs. We report here on the results of the pilotphase for a FIRST Bright Quasar Survey (FBQS). Based on matching theradio catalog from the initial 300 deg^2^ of FIRST coverage with theoptical catalog from the Automated Plate Machine (APM) digitization ofPalomar Sky Survey plates, we have defined a sample of 219 quasarcandidates brighter than E = 17.50. We have obtained opticalspectroscopy for 151 of these and classified 25 others from theliterature, yielding 69 quasars or Seyfert 1 galaxies, of which 51 arenew. identifications. The brightest new quasar has an E magnitude of14.6 and z = 0.91; four others are brighter than E = 16. The redshiftsrange from z = 0.12 to 3.42. Half of the detected objects are radioquiet with L_21-cm_ < 10^32.5^ ergs/s. We use the results of thispilot survey to establish criteria for the FBQS that will produce aquasar search program which will be 70% efficient and 95% complete to a21-cm flux density limit of 1.0 mJy.
|An image database. II. Catalogue between δ=-30deg and δ=70deg.|
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
|The Southern Vilnius Photometric System. III. Observations of E and F Harvard Standard Regions, 47 TUC and Some Metal-Deficient Stars|
The results of photoelectric photometry in the Vilnius system of 101southern stars in the areas E1--E4, E8, E9 and F1 as well as of somemetal deficient stars are presented. Photometrically determined spectraltypes and luminosity classes of these stars are also given.
|Velocity measurements in the Coma filament of galaxies|
58 new velocity measurements of galaxies located in the Coma filamentcarried out with the 2.5-m Issac Newton telescope at La Palma arepresented. These optical observations complete a sample of 21-cm lineobservations in the same region up to the 15.0th magnitude.
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