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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.
| 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 ESO-Sculptor faint galaxy redshift survey: the spectroscopic sample.
In the goal to probe the distribution of galaxies at redshiftsz=~0.1-0.5, we have started a deep redshift survey limited byR<=20.5. Using multiple object spectroscopy on the 2 largesttelescopes at the European Southern Observatory, we have so far obtained491 low-resolution spectra (~10-20A FWHM) of faint galaxies. Among the386 spectra of galaxies with R<=20.5, redshifts have been measuredfor 320 objects (81%). The spectra of 105 objects fainter than ourcatalogue limit (with R>=20.5) were also taken simultaneously and atno additionnal cost in observing time, and we derived redshifts for 47of them (43%). In this article we describe the different methods whichwe are using to reduce the spectroscopic data in a homogeneous way.Because of the low signal-to-noise ratio of the spectra, each step ofthe reduction must be optimized. Various tests are presented to evaluatethe quality of the reduced data, and the linearity and zero-point of theredshift scale are checked. Using the already available data, we presentpreliminary diagrams of the redshift distribution and the fraction ofobjects with emission-lines.
| Neutral hydrogen observations of galaxies in superclusters
Neutral hydrogen observations of spiral galaxies in the Uppsala GeneralCatalog were made with the 91 m telescope in Green Bank. Results of theH I observations are presented for 309 objects north of declination +38deg in the right ascension range between 10 h and 22 h and for a sampleof 46 objects just south of the equator in the region around R.A.between 0 h and 3 h. Many of these objects are outlying members ofsuperclusters and may be useful in the study of deviations from Hubbleflow on supercluster scales. Velocity widths as measured by fivedifferent algorithms are presented along with a profile quality index.
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