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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.
| Total magnitude, radius, colour indices, colour gradients and photometric type of galaxies
We present a catalogue of aperture photometry of galaxies, in UBVRI,assembled from three different origins: (i) an update of the catalogueof Buta et al. (1995) (ii) published photometric profiles and (iii)aperture photometry performed on CCD images. We explored different setsof growth curves to fit these data: (i) The Sersic law, (ii) The net ofgrowth curves used for the preparation of the RC3 and (iii) A linearinterpolation between the de Vaucouleurs (r(1/4) ) and exponential laws.Finally we adopted the latter solution. Fitting these growth curves, wederive (1) the total magnitude, (2) the effective radius, (3) the colourindices and (4) gradients and (5) the photometric type of 5169 galaxies.The photometric type is defined to statistically match the revisedmorphologic type and parametrizes the shape of the growth curve. It iscoded from -9, for very concentrated galaxies, to +10, for diffusegalaxies. Based in part on observations collected at the Haute-ProvenceObservatory.
| Photoelectric UBV Photometry of Galaxies in the Clusters Pegasus I, Pegasus II, Abell 262, Abell 1367, and Abell 2197-9
This paper presents photoelectric UBV multiaperture photometry of 144galaxies, 139 of which are associated with six nearby bright clusters.The observations were made at the McDonald Observatory from 1986September to 1987 November and were part of the production of the ThirdReference Catalogue of Bright Galaxies (RC3). The observations were usedto compute total magnitudes and color indices published in RC3. Theobservations can also be used to calibrate CCD images.
| 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 Tully-Fisher relation in different environments
The Tully-Fisher relation (TFR) in different environments wasinvestigated in 13 galaxy samples spanning a large range in galaxydensities, using two statistical tests to compare the TFR of differentsamples. Results of the analysis of TFR parameters in severalenvironments showed that, when samples of similar data-accuracy andmagnitude-range were compared, there was no significant differencebetween the galaxy samples. It is suggested that a comparison of sampleswith very different data accuracy or those biased by incompletenesseffects may lead to misleading results.
| KISO survey for ultraviolet-excess galaxies. X.
Presented here are the tenth list and identification charts of theultraviolet-excess galaxies which have been detected on the multi-colorplates taken with the Kiso Schmidt telescope for 10 survey fields. Inthe sky area of some 300 square degrees 490 objects are catalogued downto the photographic magnitude of about 18.
| Star-formation rates and forbidden O II emission in blue galaxies
Observations of forbidden O II 3727 A and H-beta emission-line strengthsare presented from large-aperture spectrophotometric observations ofnearby (z less than 0.1) optically blue galaxies covering a wide rangein surface brightness and luminosity. The forbidden O II emission-lineequivalent widths in these galaxies primarily lie between 30 and 100 A.Emission-line strengths in nearby blue galaxies thus resemble thosefound in faint galaxies at moderate-to-high redshifts. The most activelystar-forming nearby galaxies are characterized by surface brightness inthe forbidden O II line of about 10 to the -15th to 10 to the -14thergs/s per sq cm per sq arcsec over spatial distances of more than 1kpc. The fluxes of the forbidden O II and H-beta emission lines are wellcorrelated, and thus forbidden O II luminosities can be used to deriveapproximate star-formation rates in blue galaxies.
| Determination of the relative spectrophotometric gradients of galaxies. IV
Relative spectrophotometric gradients of continua are determined for 195galaxies. The spectra have been obtained with the 70-cm meniscustelescope of the Abastumani Astrophysical Observatory using a 2-degpreobjective prism (the reverse linear dispersion was 1200 A/mm inH-gamma). The gradient values were reduced to the AO spectral class andcorrected for light absorption in the Galaxy.
| Far-infrared properties of cluster galaxies
Far-infrared properties are derived for a sample of over 200 galaxies inseven clusters: A262, Cancer, A1367, A1656 (Coma), A2147, A2151(Hercules), and Pegasus. The IR-selected sample consists almost entirelyof IR normal galaxies, with Log of L(FIR) = 9.79 solar luminosities, Logof L(FIR)/L(B) = 0.79, and Log of S(100 microns)/S(60 microns) = 0.42.None of the sample galaxies has Log of L(FIR) greater than 11.0 solarluminosities, and only one has a FIR-to-blue luminosity ratio greaterthan 10. No significant differences are found in the FIR properties ofHI-deficient and HI-normal cluster galaxies.
| Cluster population incompleteness bias and the value of H(0) from the Tully-Fisher B0(T) relation
Data on the Virgo cluster and ten more distant clusters are the basis ofan evaluation of the influence of the cluster population incompletenessbias on the B-band Tully-Fisher relation. The data are well fitted by atheoretical curve that is obtained for a Hubble constant value of 72 +or - 5 km/sec per Mpc in the de Vaucouleurs local scale, confirming theconstant's previous determination in light of a study of the Malmquistbias for field galaxies. The true value for the Hubble constant isconcluded to lie within the 50-75 range, depending on the primarycalibration.
| A catalog of radio, optical, and infrared observations of spiral galaxies in clusters
The results of a major observational program on the luminosities,colors, and gas contents of spiral galaxies in clusters of galaxies arepresented. The data have been used as part of a detailed investigationinto the nature of cluster spirals and for revisions of the distancescale using the infrared Tully-Fisher relation. The observationalstrategies, reduction procedures, and sources or error are brieflydiscussed. The data include 21-cm H I observations, UBVR multiaperturephotometry, and H-band photometry of several hunderd spiral galaxies in10 clusters.
| Gas deficiency in cluster galaxies - A comparison of nine clusters
The available 21 cm line data in the literature for galaxies in nineclusters is combined with new high-sensitivity observations of 51galaxies in five of the nine clusters in order to test fordiscriminating circumstances between those clusters which show H Ideficiency among their spiral population and those which do not. An H Ideficiency for the complete cluster sample is derived employing acomparison sample of galaxies chosen from the Catalog of IsolatedGalaxies. The deficiency and its radial dependence is summarized foreach cluster and a composite. A comparison of the environments indifferent clusters leads to the conclusion that the occurrence of H Ideficiency is correlated with the presence of a hot X-ray intraclustermedium, and that an ongoing interaction process is active through thecores of X-ray clusters.
| A possible relationship between metal abundance and luminosity for disk galaxies
Near-infrared colors have been measured for a sample of 31 late-typegalaxies in the Pegasus I and Pisces clusters; system luminosities inthe sample cover the range of M(H) between -19 and -23.5. The colorindex (J - K) correlates strongly with the absolute H magnitude;lower-luminosity systems have bluer colors. These observations areconsistent with the assumption that the mean metal abundance of the olddisk population decreases systematically with luminosity. The systematicvariation (B - H) with absolute H magnitude reported recently by Tullyet al. (1982) derives in part from this proposed systematic change ofmetallicity with luminosity. However, a relative increase in the numberof newly formed stars and/or a systematic smaller age forlower-luminosity disks must still be posited in order to fully explainthe observed (B - H), H relation.
| Spiral galaxies in clusters. III - Gas-rich galaxies in the Pegasus I cluster of galaxies. IV - The H I color properties of spirals in nine clusters
Results of a 21-cm and optical survey of disk galaxies in the vicinityof the Pegasus I cluster of galaxies is reported, in addition to theresults of a 21-cm H I and UBV photometric survey of 235 disk galaxiesin nine nearby clusters. A substantial number of blue, gas-rich galaxiesare revealed for the Pegasus I cluster, and with few exceptions, thedisk systems in the cluster retain large amounts of neutral hydrogen,which suggests that environmental processes have not yet removedsubstantial amounts of gas from these disk galaxies. The analysis of 235disk galaxies in nearby clusters indicates that most of the clusters donot preferentially contain gas deficient spirals. The large amount of HI retained by the galaxies is not well correlated with color.
| Spiral galaxies in clusters. II - Neutral hydrogen observations in Cancer, Hercules /A 2151/, and Pegasus I
H I observations with the 305-m Arecibo telescope are reported of 67spiral galaxies in Abell 2151 (Hercules), Peg I, and the Cancerclusters. Systemic velocities, linewidths, and hydrogen masses arecomputed for the 37 galaxies detected, and upper limits on the H Icontent are derived for nondetections. The H I properties of galaxies inPeg I and Cancer are found to closely resemble those of standard, nearby'field' samples. In particular, the distance-independent qualityMH/L sub pg is in essence identical in these fields andcluster samples. Sensitivity to H I for the more distant Herculescluster is much lower, but the present results reveal only one galaxywith a value of MH/L sub pg higher than expected from thestandard sample, while several are lower than expected. It is not clearwhether this is a result of the higher luminosities of these spirals orof other conditions in the cluster.
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