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The PDS versus Markarian starburst galaxies: comparing strong and weak IRAS emitter at 12 and 25 μm in the nearby Universe
The characteristics of the starburst galaxies from the Pico dos Diassurvey (PDS) are compared with those of the nearby ultraviolet (UV)bright Markarian starburst galaxies, having the same limit in redshift(vh < 7500 km s-1) and absolute B magnitude(MB < -18). An important difference is found: theMarkarian galaxies are generally undetected at 12 and 25 μm in IRAS.This is consistent with the UV excess shown by these galaxies andsuggests that the youngest star-forming regions dominating thesegalaxies are relatively free of dust.The far-infrared selection criteria for the PDS are shown to introduce astrong bias towards massive (luminous) and large size late-type spiralgalaxies. This is contrary to the Markarian galaxies, which are found tobe remarkably rich in smaller size early-type galaxies. These resultssuggest that only late-type spirals with a large and massive disc arestrong emitters at 12 and 25 μm in IRAS in the nearby Universe.The Markarian and PDS starburst galaxies are shown to share the sameenvironment. This rules out an explanation of the differences observedin terms of external parameters. These differences may be explained byassuming two different levels of evolution, the Markarian being lessevolved than the PDS galaxies. This interpretation is fully consistentwith the disc formation hypothesis proposed by Coziol et al. to explainthe special properties of the Markarian SBNG.
| A catalog of warps in spiral and lenticular galaxies in the Southern hemisphere
A catalog of optical warps of galaxies is presented. This can beconsidered complementary to that reported by Sánchez-Saavedra etal. (\cite{sanchez-saavedra}), with 42 galaxies in the northernhemisphere, and to that by Reshetnikov & Combes(\cite{reshetnikov99}), with 60 optical warps. The limits of the presentcatalog are: logr 25 > 0.60, B_t< 14.5, delta (2000) <0deg, -2.5 < t < 7. Therefore, lenticular galaxies havealso been considered. This catalog lists 150 warped galaxies out of asample of 276 edge-on galaxies and covers the whole southern hemisphere,except the Avoidance Zone. It is therefore very suitable for statisticalstudies of warps. It also provides a source guide for detailedparticular observations. We confirm the large frequency of warpedspirals: nearly all galaxies are warped. The frequency and warp angle donot present important differences for the different types of spirals.However, no lenticular warped galaxy has been found within the specifiedlimits. This finding constitutes an important restriction fortheoretical models.
| 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.
| A multi-wavelength analysis of the cluster of galaxies ABCG 194
We present a morphological and structural analysis of the Richness zerocluster ABCG 194, known as a ``linear cluster''. This study is based ona catalogue of 97 galaxies with B magnitudes and redshifts belonging tothe cluster, a ROSAT PSPC image and radio data. We show that the overalllarge scale structure is rather smooth and comparable at optical andX-ray wavelengths. The cluster is elongated along PA ~ 50; however itappears as ``linear'' when taking into account only galaxies in the verycentral part (the axial ratio varies from 0.2 in the central region to0.8 for a larger region). We have obtained the galaxy density profileand despite the very low X-ray emission the X-ray emitting gas densityprofile. We have estimated the X-ray gas and dynamical masses up to thelimiting radius RL of the PSPC image (respectively 9 x 10(12)and 8 x 10(13) M_sun) and the stellar mass up to RL and to 3Mpc (3 10(12) and 7.5 10(12) M_sun). At smaller scales, the analysis ofboth positions and velocities reveals the existence of several groupsbut which are not strongly linked dynamically; however a main structurewith a nearly gaussian velocity distribution is exhibited. The velocitydispersion is small (sigma_ {los} = 360 km s(-1) ). A wavelet analysisof the X-ray image reveals no large scale substructures. Small scaleX-ray sources are detected, mainly corresponding to individual galaxies;we give an estimate of their luminosities. The lack of strongsubstructuring suggests that ABCG 194 is overall a relaxed cluster. ABCG194 is a poor and cold cluster; we compare how its characteristics fitinto various correlations found in the literature, but generally forricher/hotter clusters, such as the sigma-T_X, L_X-T_X, L_X-sigmarelations or the ratios of various kinds of masses.
| Groups of galaxies. III. Some empirical characteristics.
Not Available
| Environments of Redshift Survey Compact Groups of Galaxies
Redshift survey compact groups (RSCGs) are tight knots of N >= 3galaxies selected from the CfA2+SSRS2 redshift survey. The selection isbased on physical extent and association in redshift space alone. Wemeasured 300 new redshifts of fainter galaxies within 1 h^-1 Mpc of 14RSCGs to explore the relationship between RSCGs and their environments.Thirteen of 14 RSCGs are embedded in overdense regions of redshiftspace. The systems range from a loose group of five members to an Abellcluster. The remaining group, RSCG 64, appears isolated. RSCGs areisolated and distinct from their surroundings to varying degrees, as arethe Hickson compact groups. Among the 13 embedded RSCGs, three aredistinct from their general environments (RSCG 9, RSCG 11, and RSCG 85).
| Multicolour CCD surface photometry for E and S0 galaxies in 10 clusters
CCD surface photometry for 232 E and S0 galaxies is presented. Thegalaxies are observed in Gunn r and Johnson B, or Gunn r and g. For 48of the galaxies surface photometry in Johnson U is also presented.Aperture magnitudes in Gunn nu are derived for half of the galaxies.Galaxies in the following clusters have been observed: Abell 194, Abell539, Abell 3381, Abell 3574, Abell S639, Abell S753, HydraI (Abell1060), DC2345-28, Doradus and Grm15. The data are part of our ongoingstudy of the large-scale motions in the Universe and the physicalbackground for the fundamental plane. We use a full model fittingtechnique for analysing the CCD images. This gives radial profiles oflocal surface brightness, colour, ellipticity and position angle. Theresiduals relative to the elliptical isophotes are describedquantitatively by Fourier expansions. Effective radius, mean surfacebrightness and total magnitude are derived by fitting a de Vaucouleursr^¼ growth curve. We have derived a characteristic radius r_nsimilar to the diameter D_n introduced by Dressler et al. The derivationof the effective parameters and of r_n takes the seeing into account. Weconfirm the results by Saglia et al. that the effects of the seeing canbe substantial. Seeing-corrected values of the effective parameters andr_n are also presented for 147 E and S0 galaxies in the Coma cluster.Colours, colour gradients and geometrical parameters are derived. Thephotometry is internally consistent within 0.016 mag. Comparison withthe photoelectric aperture photometry from Burstein et al. shows a meanoffset of 0.010 mag with an rms scatter of 0.034 mag. The globalphotometric parameters are compared with data from Faber et al., Luceyet al. and Lucey & Carter. These comparisons imply that the typicalrms errors are as follows - log r_n:+/-0.015 log r_e:+/-0.045m_T:+/-0.09 mag; _e:+/-0.16 mag. The rms error on thecombination log r_e-0.35_e which enters the fundamental planeis +/-0.020. Also, comparisons with data from Saglia et al. arepresented. The accuracy of the absolute photometry, as well as thederived parameters, makes the data suitable for our investigations ofthe fundamental plane and of the large-scale motions in the Universe.
| A multifrequency radio continuum and IRAS faint source survey of markarian galaxies
Results are presented from a multifrequency radio continumm survey ofMarkarian galaxies (MRKs) and are supplemented by IRAS infrared datafrom the Faint Source Survey. Radio data are presented for 899 MRKsobserved at nu = 4.755 GHz with the National Radio Astronomy Observatory(NRAO)-Green Bank 300 foot (91 m) telescope, including nearly 88% ofthose objects in Markarian lists VI-XIV. In addition, 1.415 GHzmeasurements of 258 MRKs, over 30% of the MRKs accessible from theNational Aeronomy and Ionosphere Center (NAIC)-Arecibo, are reported.Radio continuum observations of smaller numbers of MRKs were made at10.63 GHz and at 23.1 GHz and are also presented. Infrared data from theIRAS Faint Source Survey (Ver. 2) are presented for 944 MRKs, withreasonably secure identifications extracted from the NASA/IPACExtragalactic Database. MRKs exhibit the same canonical infraredcharacteristics as those reported for various other galaxy samples, thatis well-known enhancement of the 25 micrometer/60 micrometer color ratioamong Seyfert MRKs, and a clear tendency for MRKs with warmer 60micrometer/100 micrometer colors to also possess cooler 12 micrometer/25micrometer colors. In addition, non-Seyfert are found to obey thewell-documented infrared/radio luminosity correlation, with the tightestcorrelation seen for starburst MRKs.
| 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.
| General study of group membership. II - Determination of nearby groups
We present a whole sky catalog of nearby groups of galaxies taken fromthe Lyon-Meudon Extragalactic Database. From the 78,000 objects in thedatabase, we extracted a sample of 6392 galaxies, complete up to thelimiting apparent magnitude B0 = 14.0. Moreover, in order to considersolely the galaxies of the local universe, all the selected galaxieshave a known recession velocity smaller than 5500 km/s. Two methods wereused in group construction: a Huchra-Geller (1982) derived percolationmethod and a Tully (1980) derived hierarchical method. Each method gaveus one catalog. These were then compared and synthesized to obtain asingle catalog containing the most reliable groups. There are 485 groupsof a least three members in the final catalog.
| Pairing properties of Markarian starburst Galaxies
The environmental parameters of 516 non-Seyfert Markarian galaxies werestudied in a redshift-bounded sample, supplemented by new spectra andredshift measures for possible companions, in order to evaluate theiroccurrence in galaxy pairs, defined through quantitative criteria. Itwas found that one-third of these galaxies occur in pairs (while only 6to 10 percent of optically-selected galaxies are known to be paired). Acomparison of various optical and IR properties of paired and nonpairedMarkarian galaxies showed no differences in the shape of the optical,far-IR, or H-alpha luminosity functions. It was found, however, that theMarkarian component is brighter than the other galaxy in each pair by0.66 magnitude in the mean at B.
| Neutral hydrogen observations of galaxies in superclusters
Neutral hydrogen observations of spiral galaxies in the Uppsala GeneralCatalog were made with the 91 m telescope in Green Bank. Results of theH I observations are presented for 309 objects north of declination +38deg in the right ascension range between 10 h and 22 h and for a sampleof 46 objects just south of the equator in the region around R.A.between 0 h and 3 h. Many of these objects are outlying members ofsuperclusters and may be useful in the study of deviations from Hubbleflow on supercluster scales. Velocity widths as measured by fivedifferent algorithms are presented along with a profile quality index.
| New measurements of radial velocities in clusters of galaxies. III
Redshifts have been obtained for 95 galaxies in eight Abell galaxyclusters using the multiobject spectrograph SILFID. Data on individualgalaxies are presented, and the accuracy of the determined velocities isdiscussed as well as some properties of the cluster. Near completesamples of galaxies have been obtained for the clusters A957, A2063, andA2589 in their central regions.
| Linear clusters of galaxies - A194
New measurements for 160 redshifts and previous measurements for 108other redshifts are presented for galaxies within 5 deg of A194. Thegalaxy distribution in A194 is shown to be inconsistent with aspherically symmetric King model. A mass-to-light ratio is derived usingthe virial theorem which is lower than the mean for the groups in theCfA redshift survey (Huchra and Geller, 1982; Geller, 1984). Anonparametric test for galaxy-cluster alignment and a Chi-squared testare used to search for alignment of galaxy major axes with the axis ofA194. Evidence for neither luminosity segregation nor significantdifferences in the velocity or surface distributions of galaxies as afunction of morphological type is found.
| A catalog of Markarian galaxies
A catalog of Markarian galaxies is presented which tabulates redshifts,spectral and morphological classifications, magnitudes, infrared andradio flux densities, and over 600 references to available datapublished before January 1, 1986. Redshifts are now available for 1228objects with strong ultraviolet continua, and follow-up spectroscopicand photometric observations of Markarian galaxies have providedclassifications of 115 Seyfert 1, 43 Seyfert 2, and 137 starburst and HII-type galaxies. After a description of the Markarian survey and thecurrent catalog, a summary of the general results obtained from the datais presented. A preliminary study of the infrared properties ofMarkarian galaxies as measured by IRAS reveals a number of interestingresults, including the existence of a sample of elliptical andlenticular galaxies with appreciable infrared emission.
| On the relation of Markarian galaxies with Zwicky clusters. I - Data
In the area covered by the survey of Markarian et al. (1967-1981) andthe CGCG of Zwicky et al. (1961-1968) there are 1344 Markarian galaxies,of which 597 are positioned inside the contours of Zwicky clusters. Dataon these galaxies and respective clusters are presented in differenttables, according to whether they are galaxies which are members ofclusters, or probable or possible members; projection cases areconsidered separately.
| A survey of galaxies in the field of A194
The galaxies in the field of the cluster Abell 194 have been surveyedusing glass plate copies of the Palomar Observatory Sky Survey. Thedistribution in the sky of the diameter-limited galaxy sample has aposition angle of 128 deg and an axial ratio of 0.72. These measurementssuggest that the line of bright galaxies at the cluster center could bea bar of an overall larger filamentary structure, as in a barred spiralgalaxy. Although no statistically significant deviation from random isfound, the galaxy position-angle distribution shows a tendency to lineup along the central bright galaxy line and at right angles to it. Thelatter direction coincides with the position angle determined for theentire sample. For disk galaxies, there is a statistically significantdeviation of the observed axial-ratio distribution from the BdVcomparison sample. An excess of edge-on galaxies and a deficiency ofgalaxies at intermediate axial ratios is found.
| A survey of galaxy redshifts. IV - The data
The complete list of the best available radial velocities for the 2401galaxies in the merged Zwicky-Nilson catalog brighter than 14.5mz and with b (II) above +40 deg or below -30 deg ispresented. Almost 60 percent of the redshifts are from the CfA surveyand are accurate to typically 35 km/s.
| Groups of galaxies. III - The CfA survey
A statistically homogeneous group catalog (CfA) is based on the CfAredshift survey (Huchra et al.) is presented. Groups in the catalog areall density enhancements in redshift space of a factor greater than 20.Group members are identified according to the procedure described in aprevious study (Huchra and Geller) of a shallower whole-sky sample. Allgroups contain at least three members. Of the 176 groups in the CfAcatalog, 102 have been identified in one or more previous studies.Because the utilized algorithm searches for volume rather than surfacedensity enhancements, the groups in a given region generally change onlythrough the addition of fainter members when the magnitude limit of thegalaxy catalog increases. In the region of overlap, agreement betweenthe shallow catalog and the CfA catalog is excellent.
| Accurate Optical Positions for Markarian Galaxies 1096-1302
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1981AJ.....86..816K&db_key=AST
| A catalog of morphological types in 55 rich clusters of galaxies
Data are presented from a study of 55 rich clusters of galaxies. Thedata include positions, morphological types, estimated total magnitudes,bulge sizes, and ellipticities for about 6000 galaxies, as determinedfrom high scale photographic plates. Data reduction procedures aredescribed, and a brief analysis of cluster richness, which indicatesthat Abell richness classes are only rough indicators of total clustermembership, is included.
| Linear clusters of galaxies
Seven linear clusters of galaxies from the catalog of Rood and Sastryhave been studied primarily to determine whether the principal axes ofthe member galaxies exhibit any tendency toward alignment. The majoraxes of galaxies in two of the clusters (Abell 999 and Abell 2197) showa distinct tendency to lie along the cluster major axes. Examination ofall the galaxies in our seven-cluster sample reveals that the major axesof these cluster members tend to lie either along or perpendicular tothe cluster major axis and avoid intermediate position angles. For thissample, there appears to be no correlation between E-galaxy flatteningand cluster shape, a result in contradiction to the recent study byStrom and Strom of ellipticals located in nine clusters of greaterrichness. Significant evidence of mass segregation is found in twoclusters (Abell 179 and Abell 194).
| Low-Dispersion Spectra of Galaxies III. Abell No. 194
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973PASP...85..104P&db_key=AST
| Spectra and Other Characteristics of Interconnected Galaxies and of Galaxies in Groups and in Clusters. III.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1964ApJ...139..269Z&db_key=AST
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