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NGC 451


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M/L, Hα Rotation Curves, and H I Measurements for 329 Nearby Cluster and Field Spirals. I. Data
A survey of 329 nearby galaxies (redshift z<0.045) has been conductedto study the distribution of mass and light within spiral galaxies overa range of environments. The 18 observed clusters and groups span arange of richness, density, and X-ray temperature and are supplementedby a set of 30 isolated field galaxies. Optical spectroscopy taken withthe 200 inch (5 m) Hale Telescope provides separately resolved Hαand [N II] major-axis rotation curves for the complete set of galaxies,which are analyzed to yield velocity widths and profile shapes, extents,and gradients. H I line profiles provide an independent velocity widthmeasurement and a measure of H I gas mass and distribution. I-bandimages are used to deconvolve profiles into disk and bulge components,to determine global luminosities and ellipticities, and to checkmorphological classification. These data are combined to form a unifieddata set ideal for the study of the effects of environment upon galaxyevolution.

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.

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.

GMRT and VLA observations of H I and OH from the Seyfert galaxy Mrk 1
We present Giant Meterwave Radio Telescope (GMRT) observations of the HI 21 cm line and Very Large Array (VLA) observations of the OH 18 cmline from the Seyfert 2 galaxy Mrk 1. H I emission is detected from bothMrk 1 and its companion NGC 451. The H I emission morphology and thevelocity field of Mrk 1 are disturbed. We speculate that the nuclearactivities of Mrk 1 are triggered by tidal interactions. We estimate theH I masses of Mrk 1 and NGC 451 to be 8.0(+/-0.6) x 108Msun and 1.3(+/-0.1)*E9 Msunrespectively. We have also detected the H I 21 cm line and the OH 18 cmline in absorption toward the nucleus of Mrk 1 at a blueshifted velocitywith respect to its systemic velocity indicating an outflow of atomicand molecular gas. Two OH lines, at 1665 and 1667 MHz, are detected.Each of the profiles of the H I and OH absorption consists of twocomponents that are separated by ~ 125 km s-1. Gaussianfitting gave dispersions of ~ 44 km s-1 for both thecomponents of the H I absorption. The profile of the OH absorption isqualitatively similar to that of the H I absorption. Both components ofthe OH absorption are thermally excited. The peak optical depths of thetwo components of the H I absorption are (7.3+/-0.4)*E-2 and(3.2+/-0.4)*E-2. The corresponding peak optical depths of the1667 MHz OH absorption are (2.3+/-0.3)*E-2 and(1.1+/-0.3)*E-2. The higher velocity components of the H Iand OH (1667 MHz) absorption lines are blueshifted from the [OIII]lambda5007 , [O I]lambda6300 , and the systemic velocity by ~ 100 kms-1, but are consistent with the [O II]lambda3727 velocity.We explain these velocity discrepancies as due to shock ionization of aregion which is pushed forward due to shocks in front of the radionucleus thereby giving apparent blueshift to H I, OH, and [O II]velocities. The optical depth ratios tauH I/tauOH1667 of both the components of the H I and OH absorption are~ 3, indicating their origin in dense molecular clouds. UsingOH/Av values for the Galactic molecular clouds, we obtain 9< Av< 90 toward the line of sight of Mrk 1.

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

Circumnuclear Stellar Population, Morphology, and Environment of Seyfert 2 Galaxies: An Evolutionary Scenario
We investigate the relation between the characteristics of thecircumnuclear stellar population and both the galaxy morphology and thepresence of close companions for a sample of 35 Seyfert 2 nuclei.Fifteen galaxies present unambiguous signatures of recent episodes ofstar formation within ~300 pc of the nucleus. When we relate thisproperty to the Hubble type of the host galaxy, we find that theincidence of recent circumnuclear star formation increases along theHubble sequence; it seems to be greater than that in non-Seyfertgalaxies for the early Hubble types S0 and Sa but similar to that innon-Seyfert galaxies for later Hubble types. In both early-type andlate-type Seyfert galaxies, the presence of recent circumnuclear starformation is related to the galaxy morphology in the inner fewkiloparsecs, as observed in Hubble Space Telescope images through thefilter F606W by Malkan et al., who have assigned a late ``inner Hubbletype'' to most Seyfert 2 galaxies with recent circumnuclear starformation. This new classification is due to the presence of dust lanesand spiral structures in the inner region. The presence of recent starformation around Seyfert 2 nuclei is also related to interactions: amongthe 13 galaxies of the sample with close companions or in mergers, ninehave recent star formation in the nuclear region. These correlationsbetween the presence of companions, the inner morphology, and theincidence of recent star formation suggest an evolutionary scenario inwhich the interaction is responsible for sending gas inward, which bothfeeds the active galactic nucleus and triggers star formation. Thestarburst then fades with time and the composite Seyfert 2+starburstnucleus evolves to a ``pure'' Seyfert 2 nucleus with an old stellarpopulation. This scenario can reconcile the hypothesis that the activenucleus in Seyfert galaxies is triggered by interactions with theresults of previous studies, which find only a small excess ofinteracting galaxies in Seyfert samples when compared with non-Seyfertsamples. The large excess can only be found early after the interaction,in the phase in which a composite (Seyfert+starburst) nucleus isobserved.

Parsec-Scale Radio Structures in the Nuclei of Four Seyfert Galaxies
We present 18 cm radio maps of four Seyfert nuclei, Mrk 1, Mrk 3, Mrk231, and Mrk 463E, made with the European VLBI Network (EVN). Linearradio structures are present in three out of four sources on scales of~100 pc to ~1 kpc, and the 20 mas beam of the EVN enables us to resolvedetails within the radio structures on scales of less than 10 pc. Mrk 3was also imaged using MERLIN, and the data were combined with the EVNdata to improve the sensitivity to extended emission. We find anunresolved flat-spectrum core in Mrk 3, which we identify with thehidden Seyfert 1 nucleus in this object, and we also see markeddifferences between the two highly collimated radio jets emanating fromthe core. The western jet terminates in a bright hot spot and resemblesan FR II radio structure, while the eastern jet has more in common withan FR I source. In the case of Mrk 463E, we use the radio and opticalstructure of the source to argue that the true nucleus liesapproximately 1" south of the position of the radio and opticalbrightness peaks, which probably represent a hot spot at the workingsurface of a radio jet. The EVN data also provide new evidence for a 100pc radio jet powering the radio source in the Type 1 nucleus of Mrk 231.However, the Seyfert 2 galaxy Mrk 1 shows no evidence for radio jetsdown to the limits of resolution (~10 pc). We discuss the range of radiosource size and morphology that can occur in the nuclei of Seyfertgalaxies and the implications for Seyfert unification schemes and forradio surveys of large samples of objects.

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.

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.

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.

Colour-selected IRAS galaxies - A comparative investigation of their radio properties
We report the results of VLA observations of two complete samples ofIRAS galaxies, one 'normal' and the other selected to have warm FIRspectra similar to those of Arp 220 and other ultraluminous infraredgalaxies. We find that these samples are indeed significantly differentin the sense that the color-selected galaxies have more centrallycondensed, higher surface brightness, and flatter spectrum radioemission in common with high-luminosity IRAS galaxies. Their FIR/radioratios are consistent with a star formation origin for the radioemission.

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.

KISO survey for ultraviolet-excess galaxies. XIV.
The 14th list and identification charts of the UV-excess galaxiesdetected on the multicolor plates taken with the Kiso Schmidt telescopefor 10 survey fields are presented. In the sky area of some 300 sq deg,about 470 objects are cataloged down to the photographic magnitude ofabout 17.5.

Objective prism survey of emission-line galaxies. IV
The results of an objective prism survey of emission-line galaxies usingthe Beijing Observatory 60-cm Schmidt are given. The survey includes 100emission-line objects, of which 96 are emission-line galaxies, 3 areplanetary nebulae and 1 is an emission-line star. Of the emission-linegalaxies, 69-72 percent are of types s or sd; 27-28 percent are of typesd and ds. In addition to 4 known Seyfert galaxies, there are at least 5probable Seyferts. Twenty-three of the objects are IRAS sourcescharacterized by strong emission phenomena.

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.

Accurate positions of Zwicky galaxies. I
Accurate optical positions, obtained from POSS prints with the BolognaInstituto di Radioastronomia position measuring machine, are given for1007 galaxies in the 502-505, 519-523, 536-539 Zwicky Catalogue fieldsaround the Abnell cluster A 262 (0150 + 3555) region. The adoptedmeasurement procedure, with a precision of about one arcsec rms, isdiscussed, and the measurements are compared with previously obtainedpositions (Dressel and Condon, 1976). With a few exceptions, the averagedeviation of the absolute value of position is 4.5 arcsec in RA and 3.4arcsec in DEC.

KISO survey for ultraviolet-excess galaxies. III
Presented here are the third list and identification charts of theultraviolet-excess galaxies which have been detected on the multicolorplates taken with the Kiso Schmidt telescope for 10 survey fields. Inthe sky area of some 300 square degrees 712 objects are catalogued downto the photographic magnitude of about 17.5.

Spectral observations of Markaryan galaxies. IV
The results are given of spectral observations of 109 Markaryan galaxiesin lists X-XI. The radial velocities, absolute magnitudes, lineardimensions, and visual estimates of the relative intensities of theemission lines are given. Among these objects, five are identified asSeyfert galaxies: Markaryan 928, 957, 984, 1058, and 1066. The massesand mass-to-luminosity ratios are estimated for four pairs and groups ofgalaxies. A list is given of 25 Markaryan galaxies for which the authorshave not discovered emission lines.

Superassociations in spiral galaxies with ultraviolet excess. II
The characteristics of the superassociations, and nuclei, of 30 spiralgalaxies discovered by Petrosian et al. (1983) are described. All thegalaxies are listed in a table which gives the galaxy number, serialnumber of the superassociation; apparent and absolute magnitudes of thenuclei; and the colors of the nuclei superassociations and galaxies. Thesizes and distances of the galaxies are given in kiloparsecs. A seriesof photographs of the galaxies is provided.

The radio emission of Markarian galaxies at wavelength 11 CM
Four hundred sixty-four objects from Markarian lists 7 to 11 wereobserved at wavelength 11 cm with a 3 sigma detection limit of 30 mJy.Fourteen Markarian galaxies were detected. Eighteen objects from earlierstudies were also reobserved to determine spectral indices and to searchfor possible variability. The measurements show that at least four andpossibly as many as eight objects are variable.

On the gravitational radius - Velocity dispersion correlation for clusters of galaxies
It is shown that there exists a correlation between the gravitationalradius, and therefore the virial mass, of each galactic cluster and itsvelocity dispersion, and possible implications are discussed. Data from22 clusters of galaxies are used, and the logarithm of the gravitationalradius is plotted versus the log of the velocity dispersion for theseclusters. The logarithm of the virial mass of the clusters is shownversus their velocity dispersion. The correlation can be interpreted todecide between theories of galaxy formation, but the lack ofsatisfactory measurements of gravitational radii and velocity dispersionof galactic clusters precludes this use of the correlation at present.

Accurate Optical Positions for Markarian Galaxies 798-1095
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1981AJ.....86..811K&db_key=AST

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Observation and Astrometry data

Constellation:Pisces
Right ascension:01h16m12.50s
Declination:+33°03'49.0"
Aparent dimensions:0.692′ × 0.525′

Catalogs and designations:
Proper Names
NGC 2000.0NGC 451
ICIC 1661
HYPERLEDA-IPGC 4594

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