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|Bar Galaxies and Their Environments|
The prints of the Palomar Sky Survey, luminosity classifications, andradial velocities were used to assign all northern Shapley-Ames galaxiesto either (1) field, (2) group, or (3) cluster environments. Thisinformation for 930 galaxies shows no evidence for a dependence of barfrequency on galaxy environment. This suggests that the formation of abar in a disk galaxy is mainly determined by the properties of theparent galaxy, rather than by the characteristics of its environment.
|The UZC-SSRS2 Group Catalog|
We apply a friends-of-friends algorithm to the combined Updated ZwickyCatalog and Southern Sky Redshift Survey to construct a catalog of 1168groups of galaxies; 411 of these groups have five or more members withinthe redshift survey. The group catalog covers 4.69 sr, and all groupsexceed the number density contrast threshold, δρ/ρ=80. Wedemonstrate that the groups catalog is homogeneous across the twounderlying redshift surveys; the catalog of groups and their membersthus provides a basis for other statistical studies of the large-scaledistribution of groups and their physical properties. The medianphysical properties of the groups are similar to those for groupsderived from independent surveys, including the ESO Key Programme andthe Las Campanas Redshift Survey. We include tables of groups and theirmembers.
|Nearby Optical Galaxies: Selection of the Sample and Identification of Groups|
In this paper we describe the Nearby Optical Galaxy (NOG) sample, whichis a complete, distance-limited (cz<=6000 km s-1) andmagnitude-limited (B<=14) sample of ~7000 optical galaxies. Thesample covers 2/3 (8.27 sr) of the sky (|b|>20deg) andappears to have a good completeness in redshift (97%). We select thesample on the basis of homogenized corrected total blue magnitudes inorder to minimize systematic effects in galaxy sampling. We identify thegroups in this sample by means of both the hierarchical and thepercolation ``friends-of-friends'' methods. The resulting catalogs ofloose groups appear to be similar and are among the largest catalogs ofgroups currently available. Most of the NOG galaxies (~60%) are found tobe members of galaxy pairs (~580 pairs for a total of ~15% of objects)or groups with at least three members (~500 groups for a total of ~45%of objects). About 40% of galaxies are left ungrouped (field galaxies).We illustrate the main features of the NOG galaxy distribution. Comparedto previous optical and IRAS galaxy samples, the NOG provides a densersampling of the galaxy distribution in the nearby universe. Given itslarge sky coverage, the identification of groups, and its high-densitysampling, the NOG is suited to the analysis of the galaxy density fieldof the nearby universe, especially on small scales.
|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.
|Groups of galaxies. III. Some empirical characteristics.|
|Bulge-Disk Decomposition of 659 Spiral and Lenticular Galaxy Brightness Profiles|
We present one of the largest homogeneous sets of spiral and lenticulargalaxy brightness profile decompositions completed to date. The 659galaxies in our sample have been fitted with a de Vaucouleurs law forthe bulge component and an inner-truncated exponential for the diskcomponent. Of the 659 galaxies in the sample, 620 were successfullyfitted with the chosen fitting functions. The fits are generally welldefined, with more than 90% having rms deviations from the observedprofile of less than 0.35 mag. We find no correlations of fittingquality, as measured by these rms residuals, with either morphologicaltype or inclination. Similarly, the estimated errors of the fittedcoefficients show no significant trends with type or inclination. Thesedecompositions form a useful basis for the study of the lightdistributions of spiral and lenticular galaxies. The object base issufficiently large that well-defined samples of galaxies can be selectedfrom it.
|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.
|The reality of anomalous redshifts in the spectra of some QSOs and its implications.|
The evidence for the physical association of close pairs involvingbright QSOs with large redshifts and bright nearby galaxies with smallredshifts, is reviewed and, in Table 1, a list of the best cases isgiven. It is shown that in a series of statistical studies usingcatalogs of QSOs and catalogs of galaxies, very strong correlations ofhigh redshift radio QSOs have been found successively with (o) [a.] TheShapley Ames Catalog of the brightest galaxies. Here the correlation iswith powerful radio QSOs with S>=9Jy (0.4GHz). The result issignificant at the 7-10σ level. (o) [b.] The Bright Galaxy Catalog(z<=0.05). Here the QSO sample is dominated by radio emitting QSOs,largely identified from the 3CR, Molonglo, Parkes, and 4C radiocatalogs. (o) [c.] The galaxies in the Lick Catalog (m<~17,z<~0.2). Again the sample of QSOs is a radio sample. (o) [d.] TheIRAS galaxy catalogs, where some fraction of the galaxies may have z upto 0.4, and where a few galaxies may be identical in position with theQSOs, but where the larger fraction have much smaller redshifts than theQSOs. Again the QSO sample is a radio sample. (o) [e.] Finally strongcorrelations on scales <~10' have been found between opticallybright, high redshift radio loud QSOs and the diffuse X-ray emissionseen by ROSAT. Bartelmann et al. (1994) believe that this diffuse X-rayemission is due to galaxy clusters at redshifts significantly less thanthe observed redshifts of the QSOs.
|A Preliminary Classification Scheme for the Central Regions of Late-Type Galaxies|
The large-scale prints in The Carnegie Atlas of Galaxies have been usedto formulate a classification scheme for the central regions oflate-type galaxies. Systems that exhibit small bright central bulges ordisks (type CB) are found to be of earlier Hubble type and of higherluminosity than galaxies that do not contain nuclei (type NN). Galaxiescontaining nuclear bars, or exhibiting central regions that are resolvedinto individual stars and knots, and galaxies with semistellar nuclei,are seen to have characteristics that are intermediate between those oftypes CB and NN. The presence or absence of a nucleus appears to be auseful criterion for distinguishing between spiral galaxies andmagellanic irregulars.
|A revised catalog of CfA1 galaxy groups in the Virgo/Great Attractor flow field|
A new identification of groups and clusters in the CfA1 Catalog ofHuchra et al. is presented, using a percolation algorithm to identifydensity enhancements. It is shown that in the resulting catalog,contamination by interlopers is significantly reduced. The Schechterluminosity function is redetermined, including the Malmquist bias.
|The far-infrared properties of the CfA galaxy sample. I - The catalog|
IRAS flux densities are presented for all galaxies in the Center forAstrophysics magnitude-limited sample (mB not greater than 14.5)detected in the IRAS Faint Source Survey (FSS), a total of 1544galaxies. The detection rate in the FSS is slightly larger than in thePSC for the long-wavelength 60- and 100-micron bands, but improves by afactor of about 3 or more for the short wavelength 12- and 25-micronbands. This optically selected sample consists of galaxies which are, onaverage, much less IR-active than galaxies in IR-selected samples. Itpossesses accurate and complete redshift, morphological, and magnitudeinformation, along with observations at other wavelengths.
|HI observations of galaxies in nearby Zwicky clusters|
The results of a long term project of H I observations of galaxieswithin the boundaries of nearby Zwicky clusters are presented. Thedetection rate is rather low (233 out of 618, i.e., 38 percent) ascompared to other surveys carried out recently. Most of the radialvelocities of the detected galaxies are new determinations. The largespread in radial velocities for many of these clusters is a strongindication for the presence of several foreground and/or backgroundgalaxies.
|The Hubble relation - Differences between galaxy types SB and SC|
It is shown that the Sb galaxies have apparent magnitudes which varyalmost exactly as if their redshifts were a measure of the distance atwhich they are observed, while the Sc do not exhibit a linear Hubblerelation. An attempt is made to determine whether the Sc discordancefrom the Hubble law is caused by Malmquist bias operating in thisfainter luminosity class of galaxies or there are inherent fundamentalpeculiarities. To this purpose the search is undertaken for other kindsof galaxies physically associated which these deviating Sc's. It isshown that luminosity criterion (Tully-Fisher) gives much smallerdistances for these galaxies than their redshifts do. The interaction ofspecific high redshift ScI's with nearby galaxies is presented as anindependent proof that ScI's are generally small, low luminositygalaxies.
|Gaseous content of galaxies inside groups|
The gaseous content of a sample constituted of 84 Sb and 95 Sc galaxiesinside groups has been analyzed. After correcting for the luminosityeffect, no gas deficiency was found for those galaxies in spite of aspan of about 2 orders of magnitude in the galaxy density. Anyintergalactic gas present in the considered groups must have densitiessmaller than 0.0003/cu cm.
|Radio emission from supernovae. I - One to twelve year old supernovae|
All recorded optical supernovae brighter than 14.0 mag from SN 1970A toSN 1981A were observed in May 1982 using VLA at 6 cm. Apart from theknown radio supernovae (SN 1970G, SN 1979C, and SN 1980K), radioemissions were not detected from any of the objects to a limit of about0.5 mJy. Limits on mass-loss rates from the presupernova systems areestablished. It is found that Type Ia Sns originate in systems whichcontain very little circumstellar material at the time of explosion.These systems are very different from those which originate Type Ib Sns.With some exceptions, Type II SNs originate with the high presupernovamass-loss rates expected from red supergiant progenitors with originalmain-sequence masses greater than about 8 solar masses.
|The Asiago Supernova Catalogue|
A Catalogue of Supernovae (SNe) is presented which tabulates the maindata relative to all extragalactic SNe discovered up to 1988 December31, and to their parent galaxies. In total 661 SNe are listed of which267 are classified. For an easier consultation, two lists are givenwhere the SNe are ordered chronologically and by Right Ascension,respectively. The overall distribution of classified supernovae over themorphological types of their parent galaxies is also presented in asummary table.
|A case for H0 = 42 and Omega(0) = 1 using luminous spiral galaxies and the cosmological time scale test|
The two principal methods of finding the Hubble velocity-distance ratiosfor individual galaxies are compared, and it is shown that one route toH0 is flawed by selection effects when using flux-limited catalogs. Theproof is made by analyzing two sets of catalogs that reach differentapparent flux levels, so that selection effects are shown directly. Theoptical data on field spiral galaxies of the brightest van den Berghluminosity class are analyzed. Calibration using M31, M81, and M101which have Cepheid distances gives H0 = 42 + or - 11 km/s/Mpc. It isshown that all values of H0 derived by the method of assigning a fixedabsolute magnitude to any given distance indicator is subject tosystematic error, giving too large an H0 value if uncorrected for bias.The age of the globular clusters is adopted to be 13.5 + or - 1 Gyr, andthe age of the universe is put at 14.9 + or - 2 Gyr. A value of Omega(0)= 1.2 + 3 or - 0.9 with Lambda = 0 is obtained.
|Cosmology from a galaxy group catalog. I - Binaries|
A new, completely objective group-finding algorithm is described andapplied to the CfA redshift catalog. The binary galaxies are isolatedfor analysis. The assumptions underlying the analysis are (1) that lighttraces mass, (2) that our binary galaxy subsets are representative lighttracers, and (3) that the binary orbits are circular. The primary resultof the work is that the resulting bias-free binary catalogs are afunction of the assumed cosmological model. For virtually any inputvalue of Omega(0) in the range 0.01-5.00, there is a reasonablyconsistent interpretation of the CfA survey such that the specifiedvalue of Omega(0) can be derived from the binary sample obtained underthat interpretation. A secondary result is that the higher the inputvalue of Omega(0), the broader the intrinsic distribution in M/L, andhence the less valid the assumption that light traces mass.
|Arm classifications for spiral galaxies|
The spiral arm classes of 762 galaxies are tabulated; 636 galaxies withlow inclinations and radii larger than 1 arcmin were classified on thebasis of their blue images on the Palomar Observatory Sky Survey (POSS),76 SA galaxies in the group catalog of Geller and Huchra were alsoclassified from the POSS, and 253 galaxies in high-resolution atlaseswere classified from their atlas photographs. This spiral armclassification system was previously shown to correlate with thepresence of density waves, and galaxies with such waves were shown tooccur primarily in the densest galactic groups. The present sampleindicates, in addition, that grand design galaxies (i.e., those whichtend to contain prominent density wave modes) are physically larger thanflocculent galaxies (which do not contain such prominent modes) by afactor of about 1.5. A larger group sample confirms the previous resultthat grand design galaxies are preferentially in dense groups.
|A prominent string of galaxies in Bootes - Evidence for a Lagrangian singularity?|
An outstanding string of galaxies and of small groups in Bootes has beenfound during a study of bridges between the Coma and the Localsuperclusters. It lies on the boundary of a large void between theHercules and the Local superclusters, has a length of 50 Mpc, is only afew megaparsecs wide, and consists of nonelliptical galaxies. A possibleexplanation by a specific Lagrangian singularity at the formation, theimprint of which has survived in the present galaxy distribution, isproposed.
|A Checklist of Supernovae in the NGC and IC Galaxies Through 1985|
This Checklist of Supernovae in the NGC and IC Galaxies Through 1985 ispresented to assist those interested in undertaking a visual orphotographic search for extragalactic supernovae. Some galaxies appearto have had more than one or two supernovae, and these should bemonitored closely for any new outbursts.
|Circumnuclear water vapor masers in active galaxies|
The results of Very Large Array observations of the very luminousextragalactic water masers in NGC 4258 and NGC 1068 are discussed. Themasers are confined to a small region in the nucleus of each galaxy lessthan 35 mas in size, corresponding to 1.34 pc in NGC 4258 and to 3.5 pcin NGC 1068. The small size suggests that luminous water masers are notdue to a large collection of 'W49-like' masers in a starburst. The veryluminous masers imply the existence of very high density neutral gaswithin the central parsec of active nuclei.
|The Malmquist bias and the value of H0 from the Tully-Fisher relation|
A large sample (n = 395) of spiral (Sab to Sd type) galaxies havingcorrected apparent magnitudes B-zero-sub-T and 21-cm line data (HI linewidths and radial velocities) is used to investigate in a new way theinfluence of the Malmquist bias on the determination of theextragalactic distance scale and the Hubble constant derived from theapplication of the B-band Tully-Fisher relation. This effect is clearlyidentified by using relative kinematic distances derived from aclassical local velocity field model and the concept of normalizedrelative kinematic distance. It results in an unbiased estimate of theHubble constant H0 which appears quite insensitive to the parameters(mean velocity of Virgo and infall velocity of the Local Group towardVirgo) adapted for the local velocity field model. A similar effect isfound from a sample of galaxies (n = 72) which are 'sosies' of 14primary galaxies. It is suggested that the presently derived H0represents the global value of the Hubble constant.
|Catalog of CO observations of galaxies|
A series of tables summarizes all observations of CO isotopes inexternal galaxies up to spring 1984. Entries include the morphologicaltype, apparent magnitude, diameter, recession velocity, and H I contentof the galaxies, and lists for the CO observations the telescope used,the features examined, the portion of the galaxy observed, the antennatemperatures of detections and their upper limits, the detected andextrapolated integrated emission, the uncertainties in the data, and thedistribution of emission in mapped galaxies. Differences in thecalibration conventions employed by observers and notations appearing inthe literature are explained, and conversion factors are derived.
|A search for environmental effects on the optical properties of galaxies in groups|
Environmental density-related modifications of basic optical properties(luminosities, sizes, axial ratios, and colors) of galaxies belonging toGeller and Huchra's (1983) groups have been investigated. Remarkably, itis found that the broad maxima of the distributions of luminosities anddiameters of spirals and the whole corresponding distributions oflenticulars tend to move to lower values as one goes to groups of highcompactness, whereas the luminosity-diameter relationship of spiralstends to become flatter. No color and axial ratio differences betweengalaxies of high- and low-compactness groups have been detected.
|A radio continuum survey of SBC spiral galaxies at 1.465 GHz|
The radio continuum emission at 1.465 GHz of 88 Sbc spiral galaxies wasobserved with the Very Large Array. The angular resolution of theobservations is about 15 arcsec, and the detection limits are about 1mJy for pointlike sources and 5-10 mJy for extended sources. A detectionrate of 82 percent was obtained. The survey provides data on the totalintensity and on the two-dimensional brightness distribution of theradio emission of the galaxies observed.
|Morphology of spiral galaxies. I - General properties|
Red Palomar Sky Survey plates are scanned to characterize a completesample of 605 spiral galaxies north of declination -33 deg havinginclination angle less than 56 deg and blue diameter 2-15 arcmin. Theselection of the data and the reduction and parameter-extractionprocedures are explained, and the data and the results of statisticalanalysis are presented in tables and graphs. Findings reported include alow frequency of occurrence for small inclination angles (suggestingdistortion of outer structures), similar distributions of central diskbrightness for types Sa-Sc but not for types Sd-Sm (where mean valuesare smaller), fewer late-type galaxies with large exponential-disk scalelengths, no galaxies with both high central brightness and large scalelength (indicating a limit on angular momentum in galaxy formation), anda correlation between mean surface brightness and absolute magnitude forlater-type galaxies but not for types Sa-Scd.
|Structure of superclusters and superclusters formation. IV Spatial distribution of clusters of galaxies in the Coma supercluster and its large-scale environment|
The Coma-A1367 Supercluster and its large-scale environment areinvestigated. The Zwicky et al. (1961-68) clusters are used assupercluster tracers; superclusters are defined not by visual impressionbut on the basis of cluster analysis. Attention is restricted to an areaof the sky where RA is between 9h and 15h, with Dec. greater than -3deg. Clustering analysis is applied to study the spatial distribution.At neighborhood radii R = 15-25 Mpc (for Hubble constant H = 50 km per sper Mpc), the clusters form chains and superclusters of galaxies. It isnoted that at R = 26-28 Mpc, superclusters merge to a single connectednetwork. Cluster chains link the Coma-A1367 Supercluster with the LocalSupercluster, A779, and Hercules Superclusters. The Coma-A1367Supercluster comprises four cluster chains, and its diameter is greaterthan 100 Mpc. It is noted that a typical cluster chain has eight Zwickyclusters and is 80 Mpc in length. Most, if not all, of the clusters formconnected systems. Empty regions devoid of clusters have diameters up to100 Mpc in this region of the sky. The morphology distribution of brightgalaxies and the mean absolute magnitude of first ranked galaxies inZwicky clusters are found to be similar to the respective quantities inAbell clusters.
|The dependence on distance and redshift of the velocity vectors of the sun, the Galaxy, and the Local Group with respect to different extragalactic frames of reference|
The solar apex S is confirmed to move steadily from S-prime toS-asterisk, when the mean redshift of the reference frame increases fromsmall to large values, on the basis of a new analysis of the solarmotion and Hubble ratio. Most of the change takes place in the 0-4000km/sec interval. The velocity vectors increase steadily, and thedirections of the apexes drift progressively as the mean distance orredshift of the reference frame increases. The frame of referencedefined by galaxies at z greater than 0.01 is essentially at rest withrespect to background radiation, suggesting that any intrinsic dipolaranisotropy of the background radiation is probably less than about0.0001.
|A revised supernova catalogue|
Essential data for 568 supernovae, discovered since 1885 up to 1983, andtheir parent galaxies are presented. This catalogue updates and revisesprevious listings, and some of its information is summarized in tabularand graphical form and briefly discussed. An appendix listing the mainreferences to observations of supernovae outside the optical range isprovided.
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