תוכן
תמונות
הוסף תמונה שלך
DSS Images Other Images
מאמרים קשורים
Redshift-Distance Survey of Early-Type Galaxies: Circular-Aperture Photometry
We present R-band CCD photometry for 1332 early-type galaxies, observedas part of the ENEAR survey of peculiar motions using early-typegalaxies in the nearby universe. Circular apertures are used to tracethe surface brightness profiles, which are then fitted by atwo-component bulge-disk model. From the fits, we obtain the structuralparameters required to estimate galaxy distances using theDn-σ and fundamental plane relations. We find thatabout 12% of the galaxies are well represented by a pure r1/4law, while 87% are best fitted by a two-component model. There are 356repeated observations of 257 galaxies obtained during different runsthat are used to derive statistical corrections and bring the data to acommon system. We also use these repeated observations to estimate ourinternal errors. The accuracy of our measurements are tested by thecomparison of 354 galaxies in common with other authors. Typical errorsin our measurements are 0.011 dex for logDn, 0.064 dex forlogre, 0.086 mag arcsec-2 for<μe>, and 0.09 for mRC,comparable to those estimated by other authors. The photometric datareported here represent one of the largest high-quality and uniformall-sky samples currently available for early-type galaxies in thenearby universe, especially suitable for peculiar motion studies.Based on observations at Cerro Tololo Inter-American Observatory (CTIO),National Optical Astronomy Observatory, which is operated by theAssociation of Universities for Research in Astronomy, Inc., undercooperative agreement with the National Science Foundation (NSF);European Southern Observatory (ESO); Fred Lawrence Whipple Observatory(FLWO); and the MDM Observatory on Kitt Peak.
| 1.65-μm (H -band) surface photometry of galaxies - VIII. The near-IR κ space at z =0
We present the distribution of a statistical sample of nearby galaxiesin the κ -space (κ 1 ~logM , κ 2~logI e 3 M /L , κ 3 ~logM /L ).Our study is based on near-IR (H -band: λ =1.65μm)observations, for the first time comprising early- and late-typesystems. Our data confirm that the mean effective dynamicalmass-to-light ratio M /L of the E+S0+S0a galaxies increases withincreasing effective dynamical mass M , as expected from the existenceof the Fundamental Plane relation. Conversely, spiral and Im/BCDgalaxies show a broad distribution in M /L with no detected trend of M/L with M , the former galaxies having M /L values about twice largerthan the latter, on average. For all the late-type galaxies, the M /Lincreases with decreasing effective surface intensity I e ,consistent with the existence of the Tully-Fisher relation. Theseresults are discussed on the basis of the assumptions behind theconstruction of the κ -space and their limitations. Our study iscomplementary to a previous investigation in the optical (B -band:λ =0.44μm) and allows us to study wavelength dependences ofthe galaxy distribution in the κ -space. As a first result, wefind that the galaxy distribution in the κ 1 -κ2 plane reproduces the transition from bulgeless tobulge-dominated systems in galaxies of increasing dynamical mass.Conversely, it appears that the M /L of late-types is higher (lower)than that of early-types with the same M in the near-IR (optical). Theorigins of this behaviour are discussed in terms of dust attenuation andstar formation history.
| 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.
| Kinematics of AWM and MKW Poor Clusters
We have measured 1365 redshifts to a limiting magnitude of R~15.5 in 15AWM/MKW clusters and have collected another 203 from the literature inMKW 4s, MKW 2, and MKW 2s. In AWM 7 we have extended the redshift sampleto R~18 in the cluster center. We have identified 704 cluster members in17 clusters; 201 are newly identified. We summarize the kinematics anddistributions of the cluster galaxies and provide an initial discussionof substructure, mass and luminosity segregation, spectral segregation,velocity-dispersion profiles, and the relation of the central galaxy toglobal cluster properties. We compute optical mass estimates, which wecompare with X-ray mass determinations from the literature. The clustersare in a variety of dynamical states, reflected in the three classes ofbehavior of the velocity-dispersion profile in the core: rising,falling, or flat/ambiguous. The velocity dispersion of the emission-linegalaxy population significantly exceeds that of the absorption-linegalaxies in almost all of the clusters, and the presence ofemission-line galaxies at small projected radii suggests continuinginfall of galaxies onto the clusters. The presence of a cD galaxy doesnot constrain the global cluster properties; these clusters are similarto other poor clusters that contain no cD. We use the similarity of thevelocity-dispersion profiles at small radii and the cD-like galaxies'internal velocity dispersions to argue that cD formation is a localphenomenon. Our sample establishes an empirical observational baselineof poor clusters for comparison with simulations of similar systems.Observations reported in this paper were obtained at the Multiple MirrorTelescope Observatory, a facility operated jointly by the University ofArizona and the Smithsonian Institution; at the Whipple Observatory, afacility operated jointly by the Smithsonian Astrophysical Observatoryand Harvard University; and at the WIYN Observatory, a joint facility ofthe University of Wisconsin-Madison, Indiana University, YaleUniversity, and the National Optical Astronomy Observatories.
| Compact groups in the UZC galaxy sample
Applying an automatic neighbour search algorithm to the 3D UZC galaxycatalogue (Falco et al. \cite{Falco}) we have identified 291 compactgroups (CGs) with radial velocity between 1000 and 10 000 kms-1. The sample is analysed to investigate whether Tripletsdisplay kinematical and morphological characteristics similar to higherorder CGs (Multiplets). It is found that Triplets constitute lowvelocity dispersion structures, have a gas-rich galaxy population andare typically retrieved in sparse environments. Conversely Multipletsshow higher velocity dispersion, include few gas-rich members and aregenerally embedded structures. Evidence hence emerges indicating thatTriplets and Multiplets, though sharing a common scale, correspond todifferent galaxy systems. Triplets are typically field structures whilstMultiplets are mainly subclumps (either temporarily projected orcollapsing) within larger structures. Simulations show that selectioneffects can only partially account for differences, but significantcontamination of Triplets by field galaxy interlopers could eventuallyinduce the observed dependences on multiplicity. Tables 1 and 2 are onlyavailable in electronic at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.125.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/391/35
| The Disk and Dark Halo Mass of the Barred Galaxy NGC 4123. I. Observations
The noncircular streaming motions in barred galaxies are sensitive tothe mass of the bar and can be used to lift the degeneracy between diskand dark matter halo encountered when fitting axisymmetric rotationcurves of disk galaxies. In this paper we present photometric andkinematic observations of NGC 4123, a barred galaxy of modest size(Vrot=130 km s-1, L=0.7L*), that revealstrong noncircular motions. The bar has straight dust lanes and an innerLindblad resonance. The disk of NGC 4123 has no sign of truncation outto 10 scale lengths, and star-forming regions are found well outsideR25. A Fabry-Perot Hα velocity field shows velocityjumps of greater than 100 km s-1 at the location of the dustlanes within the bar, indicating shocks in the gas flow. VLAobservations yield the velocity field of the H I disk. Axisymmetric massmodels yield good fits to the rotation curve outside the bar region fordisk I-band M/L of 2.25 or less, and dark halos with either isothermalor power-law profiles can fit the data well. In a companion paper wemodel the full two-dimensional velocity field, including noncircularmotions, to determine the stellar M/L and the mass of the dark halo.
| 1.65 μm (H-band) surface photometry of galaxies. III. observations of 558 galaxies with the TIRGO 1.5 m telescope
We present near-infrared H-band (1.65 μm ) surface photometry of 558galaxies in the Coma Supercluster and in the Virgo cluster. This dataset, obtained with the Arcetri NICMOS3 camera ARNICA mounted on theGornergrat Infrared Telescope, is aimed at complementing, withobservations of mostly early-type objects, our NIR survey of spiralgalaxies in these regions, presented in previous papers of this series.Magnitudes at the optical radius, total magnitudes, isophotal radii andlight concentration indices are derived. We confirm the existence of apositive correlation between the near-infrared concentration index andthe galaxy H-band luminosity Based on observations taken at TIRGO(Gornergrat, Switzerland). TIRGO is operated by CAISMI-CNR, Arcetri,Firenze, Italy. Tables 1 and 2 are only available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| 1.65 μm (H-band) surface photometry of galaxies. V. Profile decomposition of 1157 galaxies
We present near-infrared H-band (1.65 μm) surface brightness profiledecomposition for 1157 galaxies in five nearby clusters of galaxies:Coma, A1367, Virgo, A262 and Cancer, and in the bridge between Coma andA1367 in the ``Great Wall". The optically selected (mpg≤16.0) sample is representative of all Hubble types, from E to Irr+BCD,except dE and of significantly different environments, spanning fromisolated regions to rich clusters of galaxies. We model the surfacebrightness profiles with a de Vaucouleurs r1/4 law (dV), withan exponential disk law (E), or with a combination of the two (B+D).From the fitted quantities we derive the H band effective surfacebrightness (μe) and radius (re) of each component, theasymptotic magnitude HT and the light concentration indexC31. We find that: i) Less than 50% of the Ellipticalgalaxies have pure dV profiles. The majority of E to Sb galaxies is bestrepresented by a B+D profile. All Scd to BCD galaxies have pureexponential profiles. ii) The type of decomposition is a strong functionof the total H band luminosity (mass), independent of the Hubbleclassification: the fraction of pure exponential decompositionsdecreases with increasing luminosity, that of B+D increases withluminosity. Pure dV profiles are absent in the low luminosity rangeLH<1010 L\odot and become dominantabove 1011 L\odot . Based on observations taken atTIRGO, Gornergrat, Switzerland (operated by CAISMI-CNR, Arcetri,Firenze, Italy) and at the Calar Alto Observatory (operated by theMax-Planck-Institut für Astronomie (Heidelberg) jointly with theSpanish National Commission for Astronomy). Table 2 and Figs. 2, 3, 4are available in their entirety only in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| 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.
| Galaxy coordinates. II. Accurate equatorial coordinates for 17298 galaxies
Using images of the Digitized Sky Survey we measured coodinates for17298 galaxies having poorly defined coordinates. As a control, wemeasured with the same method 1522 galaxies having accurate coordinates.The comparison with our own measurements shows that the accuracy of themethod is about 6 arcsec on each axis (RA and DEC).
| The 3-D structure of the Coma-A 1367 supercluster: Optical spectroscopy of 102 galaxies
Optical spectroscopy of 117 CGCG galaxies, 102 of which are projected inthe direction of the Coma-A 1367 supercluster, is reported. These newmeasurements, added to those found in the literature, bring to 1068 thenumber of CGCG galaxies in this region with available redshift, out of atotal of 1085 objects with m_p<= 15.7. We use these data to infer the3-D structure of the Coma supercluster. Based on observations obtainedwith the Loiano telescope belonging to the University of Bologna, Italy,and with the G. Haro telescope of the INAOE, Mexico.
| 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 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.
| 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 fundamental plane of early-type galaxies: stellar populations and mass-to-light ratio.
We analyse the residuals to the fundamental plane (FP) of ellipticalgalaxies as a function of stellar-population indicators; these are basedon the line-strength parameter Mg_2_ and on UBVRI broad-band colors, andare partly derived from new observations. The effect of the stellarpopulations accounts for approximately half the observed variation ofthe mass-to-light ratio responsible for the FP tilt. The residual tiltcan be explained by the contribution of two additional effects: thedependence of the rotational support, and possibly that of the spatialstructure, on the luminosity. We conclude to a constancy of thedynamical-to-stellar mass ratio. This probably extends to globularclusters as well, but the dominant factor would be here the luminositydependence of the structure rather than that of the stellar population.This result also implies a constancy of the fraction of dark matter overall the scalelength covered by stellar systems. Our compilation ofinternal stellar kinematics of galaxies is appended.
| A Catalog of Stellar Velocity Dispersions. II. 1994 Update
A catalog of central velocity dispersion measurements is presented,current through 1993 September. The catalog includes 2474 measurementsof 1563 galaxies. A standard set of 86 galaxies is defined, consistingof galaxies with at least three reliable, concordant measurements. It issuggested that future studies observe some of these standard galaxies sothat different studies can be normalized to a consistent system. Allmeasurements are reduced to a normalized system using these standards.
| Kinematics and dynamics of the MKW/AWM poor clusters
We report 472 new redshifts for 416 galaxies in the regions of the 23poor clusters of galaxies originally identified by Morgan, Kayser, andWhite (MKW), and Albert, White, and Morgan (AWM). Eighteen of the poorclusters now have 10 or more available redshifts within 1.5/h Mpc of thecentral galaxy; 11 clusters have at least 20 available redshifts. Basedon the 21 clusters for which we have sufficient velocity information,the median velocity scale is 336 km/s, a factor of 2 smaller than foundfor rich clusters. Several of the poor clusters exhibit complex velocitydistributions due to the presence of nearby clumps of galaxies. We checkon the velocity of the dominant galaxy in each poor cluster relative tothe remaining cluster members. Significantly high relative velocities ofthe dominant galaxy are found in only 4 of 21 poor clusters, 3 of whichwe suspect are due to contamination of the parent velocity distribution.Several statistical tests indicate that the D/cD galaxies are at thekinematic centers of the parent poor cluster velocity distributions.Mass-to-light ratios for 13 of the 15 poor clusters for which we havethe required data are in the range 50 less than or = M/LB(0)less than or = 200 solar mass/solar luminosity. The complex nature ofthe regions surrounding many of the poor clusters suggests that thesegroupings may represent an early epoch of cluster formation. Forexample, the poor clusters MKW7 and MKWS are shown to be gravitationallybound and likely to merge to form a richer cluster within the nextseveral Gyrs. Eight of the nine other poor clusters for which simpletwo-body dynamical models can be carried out are consistent with beingbound to other clumps in their vicinity. Additional complex systems withmore than two gravitationally bound clumps are observed among the poorclusters.
| 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.
| Globular cluster systems associated with cD galaxies in poor clusters
We present an analysis of direct charge coupled devices (CCD) images ofthe central dominant (cD) galaxies of four poor clusters (Albert, White,& Morgan 1977; Morgan, Kayser, & White 1975) obtained at theprime focus of the Canada-France-Hawaii Telescope. A globular clustersystem (GCS) is detected in only one of the galaxies: NGC 4073 (MKW 4);it has a specific frequency of SN approximately equal 4 + or- 4, a value typical for an 'average' elliptical of no particulardistinction (Harris 1991). In the other three clusters, upper limits ofSN less than 5-10 can be set on the specific frequency of anyattendant GCS. These findings strongly suggest that mergers are notimportant in the generation of extremely populous GCSs, since thecentral galaxies in poor clusters presumably have more active merginghistories than do their counterparts in richer surroundings. It is notedthat MKW 4 has a moderate cooling flow, which may play some role in theformation of its GCS; the other poor clusters studied have neither thecooling flow nor the detected GCS. Finally, we note that the GCSassociated with NGC 4073, the cD galaxy in MKW 4, is among the leastcentrally concentrated of any studied to date. This supports asuggestion by Harris (1991) that the degree of central concentration ofa GCS is a function of the luminosity of the parent galaxy, with themost luminous galaxies having the most distended cluster systems.
| The Globular Cluster Systems of cD Galaxies in Poor Clusters
Not Available
| The surface brightness test for the expansion of the universe. III - Reduction of data for the several brightest galaxies in clusters to standard conditions and a first indication that the expansion is real
Petrosian radii, effective radii, apparent magnitudes, and averagesurface brightnesses are presented for the first few ranked galaxies in56 nearby clusters and groups. The correlations between (SB) and both Mand R are derived from the data, and a selection effect that imitates aTolman signal in these data but which is an artifact of the sample isdiscussed. Correction procedures are applied to the high-redshift galaxysample of Djorgovski and Spinrad (1981), and a well-defined Tolmansignal is found in the data. Although this appears to be strong proofthat the universe expands and therefore that the conventionalinterpretation of the redshift is correct, the reliability of theconclusion is cautioned. Methods to optimize the Tolman test in futureobservational programs are discussed.
| Statistics of galaxy orientations - Morphology and large-scale structure
Using the Uppsala General Catalog of bright galaxies and the northernand southern maps of the Lick counts of galaxies, statistical evidenceof a morphology-orientation effect is found. Major axes of ellipticalgalaxies are preferentially oriented along the large-scale features ofthe Lick maps. However, the orientations of the major axes of spiral andlenticular galaxies show no clear signs of significant nonrandombehavior at a level of less than about one-fifth of the effect seen forellipticals. The angular scale of the detected alignment effect forUppsala ellipticals extends to at least theta of about 2 deg, which at aredshift of z of about 0.02 corresponds to a linear scale of about 2/hMpc.
| A VLA 20 CM survey of poor groups of galaxies
The paper reports on VLA 20 cm observations of an extensive sample ofgalaxies in 139 poor groups. These groups, composed of galaxies down tothe limit of the Zwicky et al. (CGCG) catalog, were chosen using apercolation algorithm set at a high surface-density threshold.Approximately 50 percent of the groups have measured redshifts. Thesegroups were surveyed using a 'snapshot' mode of the VLA with aresolution of about 13 arcsec. Analysis of the resulting radio andoptical properties reveals that the presence of a nearby companiongalaxy has an important role in generating radio emission in a galaxy.CCD observations of two radio-loud, disturbed galaxies with companionsare presented and are used to discuss models of radio-source production.Nine tailed radio galaxies are found in the poor groups, which is muchmore than had been expected from previous work on rich clusters and fromtheoretical models. The paper discusses previous statistical biases andproposes a method for bending head-tail sources in poor groups. From theconfinement of extended radio features associated with tailed sources,the presence of a substantial intracluster medium that should radiatesignificantly at soft-X-ray energies is predicted.
| Photometric properties of poor clusters of galaxies
Photographic pahotometry was made for sixteen poor clusters of galaxieslisted by Morgan et al. (1975) and Albert et al. (1977). Data were fromthe V-band plates taken with the 105-cm Schmidt telescope of the KisoObservatory. Luminosity functions of individual clusters are obtained byapplying a detailed statistical field correction. The compositeluminosity function of poor clusters is found to be similar to those ofrich clusters and small groups of galaxies. The luminosity of the firstranked galaxies of the poor clusters is closely related to the amount ofhot intracluster gas and total visible mass in the systems.
| Taxonomical analysis of superclusters. II - The A1367/Coma supercluster
The nonhierarchical taxonomical method has been applied to a sample of185 galaxies, complete to m not greater than 15, in the A1367/Comaregion. Once the fore- and background galaxies have been identified, theanalysis of the A1367 cluster shows it composed by two gravitationallybound clumps at essentially the same redshift, 6396 km/s and 6562 km/s,respectively. Central Coma is traced by three different groups whosegravitational binding does not appear clearly. However, accepting theunique dynamical entity of Central Coma, some other neighboring groupswould be part of the cluster. In that case, the average radial velocityand dispersion of the Coma cluster would be 7013 and 423 km/s,respectively. The M/L ratios for the groups evidenced by the taxonomyrange from 13 to 170. The missing mass problem only appears when all thegalaxies in the sample are considered as members of a unique dynamicalstructure. The relationship found in other systems between the redshift,the morphological type and the radioemissivity is also present in thesample.
| CD galaxies of apparent supergiant sizes due to the curvature of space
Evidence for a positively curved universe is examined, and a model isdeveloped by combining two two-dimensional subspaces which are closedinto themselves due to curvature, to create a model of three-dimensionalspace of the same properties. A law of fictitious magnification isproposed. Indirect evidence for spherically curved space (and for thenonexistence of negative curvature) includes superluminal velocities,the existence of supergiant galaxies such as cD's, the superposition ofgalaxies, and the occurrence of background radiation. The theory impliesthe existence of another interpretation of spectra into redshifts. Theoccurrence of a gravitational lens effect, giving amplification of thecontours of foreground galaxy images, results in spectra beingintermixed.
| Photometry of 18 clusters of galaxies
Data accumulated in the study of the poor clusters of galaxiesidentified by Morgan, Kayser, and White (1975) and Albert, White, andMorgan (1977) as well as two rich clusters are presented. The reductionsystem developed for the present study (the Kiso Image Detection System)is described. Positions, apparent magnitudes, ellipticities, and majoraxis position angles are provided.
| Radio continuum survey of the Coma/A1367 supercluster. II - 1.5 GHz observations of 396 CGCG galaxies
1.5 GHz VLA radio continuum observations of 396 relatively isolated CGCGgalaxies in the Coma/A1367 supercluster yielded the detection of 95objects. These observations, added to the ones presented in previouspapers, form a complete sample of optically selected objects with m(p)equal to or less than 15.3. Two wide-angle-tailed sources have beenfound in smaller groups within the supercluster.
| A catalog of stellar velocity dispersions. I - Compilation and standard galaxies
A catalog of central stellar velocity dispersion measurements ispresented, current through June 1984. The catalog includes 1096measurements of 725 galaxies. A set of 51 standard galaxies is definedwhich consists of galaxies with at least three reliable, concordantmeasurements. It is suggested that future studies observed some of thesestandard galaxies in the course of their observations so that differentstudies can be normalized to the same system. Previous studies arecompared with the derived standards to determine relative accuracies andto compute scale factors where necessary.
|
הכנס מאמר חדש
לינקים קשורים
הכנס לינק חדש
משמש של הקבוצה הבאה
|
תצפית ומידע אסטרומטרי
קטלוגים וכינוים:
|
