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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.
|Lopsidedness in Early-Type Disk Galaxies|
We quantify the mean asymmetry of 54 face-on, early-type disk galaxies(S0 to Sab) using the amplitude of the m = 1 azimuthal Fourier componentof the R-band surface brightness. We find that the median lopsidedness,, of our sample is 0.11 and that the most lopsided 20% ofour galaxies have >= 0.19. Asymmetries in early-typedisks appear to be of similar frequency and strength as in late-typedisk galaxies. We have observed our early-type disks in a bandpass (Rband) in which the light is dominated by stars with ages greater than10^9 yr and therefore are seeing azimuthal asymmetries in the stellarmass distribution. The similar degree of lopsidedness seen in disks ofvery different star formation rates indicates that the lopsidedness inall galactic disks is primarily due to azimuthal mass asymmetries.Hence, 20% of all disk galaxies (regardless of Hubble type) haveazimuthal asymmetries, >= 0.19, in their stellar diskmass distribution, confirming lopsidedness as a dynamical phenomenon.
|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.
|Large-Scale Structure at Low Galactic Latitude|
We have extended the CfA Redshift Survey to low galactic latitudes toinvestigate the relation between the Great Wall in the North GalacticCap and the Perseus-Pisces chain in the South Galactic Cap. We presentredshifts for 2020 galaxies in the Catalogue of Galaxies and of Clustersof Galaxies (Zwicky et al. 1961-68, CGCG) in the following regions: 4^h^<= α <= 8^h^, 17^h^ <= α <= 20^h^, 0^deg^ <=δ <= 45^deg^. In these regions, the redshift catalogue includes1664 galaxies with B(0) <= 15.5 (of which 820 are newly measured) andis 97% complete. We also include redshifts for an additional 356galaxies in these regions with B(O) > 15.5; of these, 148 werepreviously unmeasured. The CGCG samples the galaxy distribution down tob_II_ = 10^deg^. In this paper, we discuss the acquisition and reductionof the spectra, and we examine the qualitative features of the redshiftdistribution. The Great Wall and the Perseus-Pisces chain are not simplyconnected across the Zone of Avoidance. These structures, which at firstappear to be coherent on scales of ~100 h^-1^ Mpc or more, actually formthe boundaries of neighboring voids of considerably smaller scale,approximately 50h^-1^ Mpc. The structures delineated by ouroptically-selected sample are qualitatively similar to those detected bythe far-infrared-selected IRAS 1.2 Jansky Survey (Fisher et al. 1995).Although the IRAS survey probes more deeply into the Zone of Avoidance,our optically-selected survey provides better sampling of structures atb_II_ >= 10^deg^.
|Photoelectric UBV Photometry of 179 Bright Galaxies|
This paper presents photoelectric UBV multiaperture photometry of 179bright galaxies that was used to compute total magnitudes and colorindices published in the Third Reference Catalog of Bright Galaxies(RC3). The observations were made at the McDonald Observatory from 1983December to 1986 September with an Amperex 56-DVP photometer attached tothe 0.76 and 0.91 m telescopes. The observations can also be used tocalibrate CCD images.
|Integrated photoelectric magnitudes and color indices of bright galaxies in the Johnson UBV system|
The photoelectric total magnitudes and color indices published in theThird Reference Catalogue of Bright Galaxies (RC3) are based on ananalysis of approximately equals 26,000 B, 25,000 B-V, and 17,000 U-Bmultiaperture measurements available up to mid 1987 from nearly 350sources. This paper provides the full details of the analysis andestimates of internal and external errors in the parameters. Thederivation of the parameters is based on techniques described by theVaucouleurs & Corwin (1977) whereby photoelectric multiaperture dataare fitted by mean Hubble-type-dependent curves which describe theintegral of the B-band flux and the typical B-V and U-B integrated colorgradients. A sophisticated analysis of the residuals of thesemeasurements from the curves was made to allow for the random andsystematic errors that effect such data. The result is a homogeneous setof total magnitudes BTA total colors(B-V)T and (U-B)T, and effective colors(B-V)e and (U-B)e for more than 3000 brightgalaxies in RC3.
|Arm structure in normal spiral galaxies, 1: Multivariate data for 492 galaxies|
Multivariate data have been collected as part of an effort to develop anew classification system for spiral galaxies, one which is notnecessarily based on subjective morphological properties. A sample of492 moderately bright northern Sa and Sc spirals was chosen for futurestatistical analysis. New observations were made at 20 and 21 cm; thelatter data are described in detail here. Infrared Astronomy Satellite(IRAS) fluxes were obtained from archival data. Finally, new estimatesof arm pattern radomness and of local environmental harshness werecompiled for most sample objects.
|Properties of the redshift. I - Data and calibrations|
Data at 21 cm are presented for 100 galaxies intended to be used forsystem comparisons between the NRAO 140 and 300 foot telescope and the100 m Effelsberg telescope. Data from the 300 foot telescope are alsogiven for galaxies selected for overlap comparisons with older studies.Flux calibrations and measurement uncertainties in flux, redshifts,profile width, and profile shape are discussed.
|The peculiar velocity of the Local Group. II - H I observations of SC galaxies|
H I observations of a sample of 163 Sc galaxies have been obtained usingthe Mk IA and Mk II Jodrell Bank radio telescopes. In the presentanalysis, the overall rms error in redshift determination is 5 km/s andthe rms error in velocity width determination is 10 km/s. The resultssuggest that Sc galaxies have high internal obscuration and may beoptically thicker in blue light than earlier-type spirals. An orthogonalthree-dimensional classification system based on three uncorrelatedparameters related to linear diameter, quiescent star-formation rate,and embedded starburst-type activity is shown to account for the globalproperties of Sc galaxies with an accuracy close to the limit ofmeasurement error.
|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.
|An Arecibo survey for extragalactic hydroxyl absorption. I - Presentation of results|
Hydroxyl absorption has been detected in a total of 24 galaxies;megamaser emission in six additional galaxies brings the total number ofdetections of extragalactic OH to 30. About 50 percent of theextragalactic absorption lines are asymmetrically skewed toward the red,indicating that the molecular disks could have an unusual velocity orexcitation structure. The hyperfine ratio for the 1667 and 1665 MHztransitions in most galaxies lies within the limits specified by LTEconditions.
|High signal-to-noise ratio observations of H I in 243 galaxies|
The 21 cm spectral-line system of the Arecibo Observatory was used tomeasure neutral hydrogen emission from 243 faint galaxies. Most lie nearthe plane of the Local Supercluster. All observations reach anunsmoothed signal-to-noise ratio of at least 7.0; the average for theset is 23. The resulting data are used to estimate H I masses, systemicvelocities, and accurate profile widths at 20 percent, 25 percent, 50percent, and 80 percent of peak intensity levels. The widths are used tocalibrate directly the bias introduced by popular data-smoothingoperation. The data include observations of 65 objects with previouslyunknown redshifts.
|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.
|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.
|H I line studies of galaxies. III - Distance moduli of 822 disk galaxies|
The distance scale established on the basis of a distance moduli catalog(for 822 galaxies) that was derived from 21-cm line widths via theB-band Tully-Fisher relation is compared with several independent scaleshaving a common zero point, that are based on the indicators forluminosity index, redshift, ring diameters, brightest superassociations,and effective diameters. These are in excellent systematic agreement,and confirm the linearity of the H I scale in the 24-35 modulusinterval, but indicate a small systematic zero point difference of about0.2 mag, which must be added to the H I moduli to place them on the same'short' distance scale defined by the others.
|Inner ring structures in galaxies as distance indicators. III - Distances to 453 spiral and lenticular galaxies|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983ApJS...51..149B&db_key=AST
|Corrections to the Reference Catalogue of Bright Galaxies (Third List)|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972PASP...84..462C&db_key=AST
|Photographs of nebulae with the 60-inch reflector 1911-1916.|
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