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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.
|A Wide Field CCD Survey for Low Surface Brightness Galaxies:I.Data Acquisition, Description, and Initial Results|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....113.1212O&db_key=AST
|Peculiar Velocities for Galaxies in the Great Wall.II.Analysis|
We analyze the peculiar velocity field in the vicinity of the Great Wall(GW) using a sample of 172 spiral galaxies with reliable IRTF distanceestimates (Dell'Antonio et al. 1996). We examine three main issues: (1)the infall onto the GW, (2) large-scale flow, and (3) shear. We use aMonte Carlo method to remove selection-based biases from the peculiarvelocity sample. For the GW sample, the velocity bias is small (<150km s^-1^). We use the bias-corrected velocities to constrain the infalltowards the Great Wall. We thus have the first limits on the truespatial thickness of this structure. The data are best fit by an infallvelocity <= 150 km s^-1^. The 90% upper limit on the mean infallvelocity is ~500 km s^-1^. Consequently, the upper limit on thereal-space full width of the GW is d<11.2h^-1^ Mpc. Thus, the GreatWall is a thin, two- dimensional structure in real space as well as inredshift space. We calculate the best-fit estimate of the motion of theLocal Group with respect to the galaxy distribution: ν_flow_ ~725+/-400 km s^-1^ towards a 11.7 +/- 1.5 hr, δ =36.8deg^+/-55^deg^. Because our δ constraints are quiteweak, this flow is consistent with the CMB dipole (Smoot et al. 1992)and with the flow vector of Riess et al. (1995). The data are alsoconsistent at the 25% confidence level with the direction of large-scaleflow reported by Lauer & Postman (1994). We calculate theimprovement in sensitivity expected for a sample extending over the fulldeclination range of the GW. We also calculate the shear across theright ascension range of the GW. The GW region is quiet: the detectedthe shear across the range of the GW is -70+/-210 km s^-1^. The absenceof large shear constrains the amplitude of large-scale densityfluctuations (Feldman & Watkins 1995).
|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.
|Associations between quasi-stellar objects and galaxies|
A table is presented here listing all close pairs of QSOs and galaxiesthat were found in a computer-aided search of catalogs of QSOs andbright galaxies and an extensive search of the literature. There is alarge excess of pairs with separations of 2 arcmin lor less, or about 60kpc, over the numbers expected if the configurations were accidental.The angular separation for 392 pairs adds to the evidence for physicalassociation, and it is shown that selection effects are not important. Ageneral rule is stated that QSOs tend to lie in the vicinity of normalgalaxies much more often than is expected by chance whether or not thegalaxies and the QSOs have the same redshifts. It is emphasized thatthis rule cannot be explained in terms of gravitational microlensing,and it is concluded that some part of the redshift of all classes ofactive nuclei is not associated with the expansion of the universe.
|A Study of the Largescale Structure in the Distribution of Galaxies in a Region Centered about the Cancer Cluster - Part Two - Further Observational Results|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986AJ.....91..732B&db_key=AST
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