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The Arecibo Legacy Fast Alfa Survey. V. The H I Source Catalog of the Anti-Virgo Region at δ = +27°
We present a second catalog of H I sources detected in the AreciboLegacy Fast ALFA Survey. We report 488 detections over 135deg2, within the region of the sky having 22 h < α< 03 h and +26° < δ < +28°. We present here thedetections that have either (a) S/N>6.5, where the reliability of thecatalog is better than 95% or (b) 5.0 < S/N < 6.5 and a previouslymeasured redshift that corroborates our detection. Of the 488 objectspresented here, 49 are high-velocity clouds or clumps thereof withnegative heliocentric recession velocities. These clouds are mostly verycompact and isolated, while some of them are associated with largefeatures such as Wright's Cloud or the northern extension of theMagellanic Stream. The remaining 439 candidate detections are identifiedas extragalactic objects and have all been matched with opticalcounterparts. Five of the six galaxies detected with M☉ are satellites of either the NGC672/IC1727 nearbygalaxy pair or their neighboring dwarf irregular galaxy NGC784. The dataof this catalog release include a slice through the Pisces-Perseusforeground void, a large nearby underdensity of galaxies. We report nodetections within the void, where our catalog is complete for systemswith masses of 108 M ☉. Gas-rich,optically-dark galaxies do not seem to constitute an important voidpopulation, and therefore do not suffice for producing a viable solutionto the void phenomenon.
| A Digital Archive of H I 21 Centimeter Line Spectra of Optically Targeted Galaxies
We present a homogeneous compilation of H I spectral parametersextracted from global 21 cm line spectra for some 9000 galaxies in thelocal universe (heliocentric velocity-200
| A Redshift Survey of Nearby Galaxy Groups: The Shape of the Mass Density Profile
We constrain the mass profile and orbital structure of nearby groups andclusters of galaxies. Our method yields the joint probabilitydistribution of the density slope n, the velocity anisotropy β, andthe turnover radius r0 for these systems. The measurementtechnique does not use results from N-body simulations as priors. Weincorporate 2419 new redshifts (included here) in the fields of 41systems of galaxies with z<0.04. The new groups have median velocitydispersion σ=360 km s-1. We also use 979 archivedredshifts in the fields of eight nearly relaxed clusters with z<0.1.Within R<~2r200, the data are consistent with a singlepower-law matter density distribution with slope n=1.8-2.2 for systemswith σ<470 km s-1 and n=1.6-2.0 for those withσ>470 (95% confidence). We show that a simple, scale-freephase-space distribution function (DF)f(E,L2)~(-E)α-1/2L-2β isconsistent with the data as long as the matter density has a cusp. Usingthis DF, matter density profiles with constant-density cores (n=0) areruled out with better than 99.7% confidence.
| Physical Coupling of Kazarian Galaxies with Surrounding Galaxies
Results from a statistical study of Kazarian galaxies and the objectssurrounding them are presented. It is shown that: (1) the sample ofKazarian galaxies up to 16m.0 is complete. (2) Roughly 35.7% of theKazarian galaxies are members of clusters, 14.0% of groups, and 13.6% ofbinary systems, while 36.7% are single galaxies. (3) Of the 580 Kazariangalaxies, roughly 61.2% are infrared, 8.8% radio, and 2.8% x-raysources. (4) The relative numbers of Kazarian galaxies for completesamples of I, R, and X in the different groups are systematically higherthan the corresponding numbers for samples of all Kazarian galaxies.
| 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).
| 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.
| Spectrophotometric investigation of five galaxies with a UV excess.
Not Available
| Morphological classification of new galaxies with a UV excess
The results of a morphological classification of 580 galaxies with a UVexcess, included in the lists in [M. A. Kazarian, Astrofizika,15, 5(1979); ibid.,15, 193 (1979); M. A. Kazarian and É. S. Kazarian,ibid.,16, 17 (1980); ibid.,18, 512 (1982); ibid.,19, 213 (1983)], arepresented. For this we have developed a set of symbols, using the typesE, S, and Ir introduced by Hubble, as well as symbols introduced byother authors and us. This set enabled us to make the morphologicalclassification. Direct photographs obtained on the 2.6-m and 6-mtelescopes were used to classify 141 of the galaxies (over 24%), whilePalomar Atlas charts were used for the remaining 439 galaxies. Thesegalaxies were divided into two groups based on classificationconditions, and data on each group are given in Tables 1 and 2,respectively. The results for each group, given in Table 3, show thatwith the transition from early types, such as C and E, to later types,such as S and Ir, the relative number of galaxies going into one group(Table 1), in which the classification was based on direct photographs,increases in comparison with the number going into the other group(Table 2).
| KISO survey for ultraviolet-excess galaxies. XI
Charts of UV-excess galaxies detected on multicolor plates with the KisoSchmidt telescope are presented. A total of 10 survey field areconsidered. In a 300-sq-deg sky area, 460 objects are cataloged to aphotographic magnitude of about 18.
| A 21 CM survey of the Pisces-Perseus supercluster. IV - Addenda to the declination zone 21.5 deg to 33.5 deg
Using the 305-m Arecibo telescope, 21-cm line data on 472 disk galaxiesin the Pisces-Perseus supercluster have been obtained. Data on galaxiessmaller than 1 arcmin are presented for the declination strips coveredin previous studies (Giovanelli and Haynes, 1985 and Giovanelli et al.,1986). Tables of the 21-cm line data for this region are presented.
| Spectral observations of new galaxies with UV excess. II
Results of spectral observations of 41 galaxies with UV excess arepresented. The spectra were obtained with the 6-m telescope of theSpecial Astrophysicl Observatory. Emission lines were observed in thespectra of 36 galaxies. Four objects, 147, 214, 323, and 336 are of theSeyfert type (Sy 2), while one galaxy, 238, is a Seyfert candidate.
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