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A search for Low Surface Brightness galaxies in the near-infrared. I. Selection of the sample
A sample of about 3800 Low Surface Brightness (LSB) galaxies wasselected using the all-sky near-infrared (J, H and Ks-band)2MASS survey. The selected objects have a mean central surfacebrightness within a 5'' radius around their centre fainter than 18 magarcsec-2 in the Ks band, making them the lowestsurface brightness galaxies detected by 2MASS. A description is given ofthe relevant properties of the 2MASS survey and the LSB galaxy selectionprocedure, as well as of basic photometric properties of the selectedobjects. The latter properties are compared to those of other samples ofgalaxies, of both LSBs and ``classical'' high surface brightness (HSB)objects, which were selected in the optical. The 2MASS LSBs have aBT_c-KT colour which is on average 0.9 mag bluerthan that of HSBs from the NGC. The 2MASS sample does not appear tocontain a significant population of red objects.All tables and Figs. 2a-c are only available in electronic form athttp://www.edpsciences.org

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.

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 ( or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/391/35

Gas-rich Dwarfs from the PSS-II. III. H I Profiles and Dynamical Masses
We present Arecibo neutral hydrogen data on a sample of opticallyselected dwarf galaxies. The sample ranges in H I mass from106 to 5×109 Msolar, with a meanof 7.9×108 Msolar. Using estimated H Iradii, the H I surface densities range from 0.6 to 20 Msolarpc-2, all well below the critical threshold for starformation (Kennicutt 1998). MH I/L values of the LSB dwarfsrange from 0.3 to 12 with a mean value of 2.0. Dynamical masses,calculated from the H I profile widths, range from 108 to1011 Msolar. There is a strong correlation betweenoptical luminosity and dynamical mass for LSB dwarfs implying that thedark matter (whether baryonic or nonbaryonic) follows the detectablebaryonic matter.

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.

Investigation of Barred Galaxies. V. Surroundings of SB and SA Galaxies
Not Available

Catalogue of HI maps of galaxies. I.
A catalogue is presented of galaxies having large-scale observations inthe HI line. This catalogue collects from the literature the informationthat characterizes the observations in the 21-cm line and the way thatthese data were presented by means of maps, graphics and tables, forshowing the distribution and kinematics of the gas. It containsfurthermore a measure of the HI extension that is detected at the levelof the maximum sensitivity reached in the observations. This catalogueis intended as a guide for references on the HI maps published in theliterature from 1953 to 1995 and is the basis for the analysis of thedata presented in Paper II. The catalogue is only available inelectronic form at the CDS via anonymous ftp orhttp://cdsweb.u-strasbg.fr/Abstract.html

Gas-rich Dwarfs from the Second Palomar Sky Survey. I. Catalog and Characteristics
This project is a visual search for field dwarf galaxies using SecondPalomar Sky Survey photographic plates. A morphologically selectedsample of 310 objects yielded 145 detections of true dwarfs within aredshift search window of 0 to 10,000 km s-1. We confirm the low-mass,dwarf nature of the same by comparison of luminosity, isophotal size, HI mass and H I profile width distribution of other dwarf samples. Thegoal of this project is to use these newly discovered dwarf galaxies tomap large-scale structure as a test of biased galaxy formation. Initialindicators are that the large-scale distribution of dwarf galaxies isidentical to that of bright, high-mass galaxies, in contradiction totheory using biasing. The full analysis of the sample will be reportedin the final paper of our series.

VLA Observations of NGC 253: Supernova Remnants and H II Regions at 1 Parsec Resolution
The edge-on starburst galaxy NGC 253 has been imaged with the VLA atwavelengths ranging from 1.3 to 20 cm, with resolutions between 1 and 15pc. These images reveal a large number of compact radio sources embeddedwithin the diffuse radio structure in the inner 200 pc of the galaxy. Wehave identified approximately 64 individual compact radio sources in thegalaxy. Of the strongest 17 sources, for which the flux densities arehigh enough to measure spectral indices with moderately low errors,about half have flat spectra and half have steep spectra; this indicatesthat perhaps half of the individual radio sources are dominated bythermal radio emission from H II regions. Over an 8 yr timescale, few,if any, of the strongest sources have varied in flux density, withlimits of 1%--2% yr-1 on the rate of decrease. At the highest resolutionof 1 pc, a number of radio sources are beginning to be resolved, and atleast 15 different sources can be identified within the innermost 20 pcof the galaxy. Individual radio sources have been explored in moredetail. The strongest source, 5.79-39.0 (TH2), assumed to be at thenucleus of the galaxy, has a brightness temperature greater than 20,000K at 22 GHz and greater than 40,000 K at 15 GHz. It is unresolved at theVLA and may be either an active galactic nucleus or a very compact(nonvariable) supernova remnant. A resolved flat-spectrum source,5.72-40.1 (TH6), is located ~20 pc to the southwest. It has an apparentsize of 2.4 x 1.2 pc and appears to be an H II region similar to theinner part of 30 Doradus, containing approximately 105 Mȯ in stars,as well as ~600 Mȯ of ionized gas. Source counts, the lack ofvariability, and the lack of new sources imply that the radio supernovarate is no more than 0.3 yr-1, consistent with estimates made in otherwave bands.

Influence of a partial incompleteness of the sample on the determination of the Hubble constant.
This paper presents a study of the Malmquist bias effect in thedetermination of the Hubble constant from the method of "sosies"(look-alike) galaxies. It is shown that a bias appears when a partialincompleteness exists in the sample. A new method, based on the use ofthe completeness curve, is proposed to correct for such a bias. Afterthis correction, the Hubble constant drops of about 20% just because ofthe existence of the partial incompleteness. From the present resultsand on the acceptance of the distance modulus of primary calibrators,the value of the Hubble constant would be: H_0_=~60km/s/Mpc with aninternal statistical error of about 2km/s/Mpc.

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.

Groups of galaxies within 80 Mpc. II - The catalogue of groups and group members
This paper gives a catalog of the groups and associations obtained bymeans of a revised hierarchical algorithm applied to a sample of 4143galaxies with diameters larger than 100 arcsec and redshifts smallerthan 6000 km/s. The 264 groups of galaxies obtained in this way (andwhich contain at least three sample galaxies) are listed, with the looseassociations surrounding them and the individual members of eachaggregate as well; moreover, the location of every entity among 13regions corresponding roughly to superclusters is specified. Finally,1729 galaxies belong to the groups, and 466 to the associations, i.e.,the total fraction of galaxies within the various aggregates amounts to53 percent.

Uncertainties in 21 centimeter redshifts. I - Data
High-precision data on the 21-cm redshifts, profile widths, and shapesfor 625 galaxies are presented. Each galaxy is listed in across-identification and morphology table. High-resolution spectra arealso given for each galaxy. Internal redshift consistency is roughly 1km/s for galaxies for which the S/N is above 15. No systematic effectshave been found which might influence the observed redshift quantizationat 72.5 km/s or its submultiples.

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.

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.

H I line studies of galaxies. IV - Distance moduli of 468 disk galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...59...43B&db_key=AST

Separations of H II regions in galaxies
Separations of H II regions in a sample of 44 late type galaxies aredetermined. The distribution function of the linear separations followsan exponential law. This distribution function may be used as secondarystandard for distance determinations of galaxies. Typical values of theseparations are of the order of 300 pc; they reflect an important scalelength in the process of star formation.

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.

A catalogue of HI diameters for 238 galaxies
A large catalog of effective H I diameters for 238 galaxies has beencompiled from new measurements made with the Nancay radiotelescope (40percent of the catalog), and previously published diameters homogenizedto the same definition. A good covering both in morphological types andin luminosity within each type is thus achieved.

The radial distribution of H II regions in spiral galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983ApJ...267..563H&db_key=AST

21-cm observations of galaxies in groups and multiplets
Measures at the 21-cm line of neutral hydrogen are reported for a largesample of individual galaxies in groups as well as for interactingmultiple-component systems. The observations of single galaxies weredesigned to study differential redshifts within groups. Observations ofinteracting systems were undertaken to obtain system redshifts as wellas 21-cm profile morphology. The data, which will be used in futureanalyses, are presented here along with a discussion of interactionmorphology from the 21-cm profile point of view. Together the profilesamples encompass the full range of dynamical states in which the gascomponents of galaxies are observed, from relaxed to violentlydisrupted.

An atlas of H II regions in 125 galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983AJ.....88..296H&db_key=AST

Optical surveys of H II regions in galaxies
Optical surveys of individual galaxies now include many hundreds of H IIregions per galaxy. The present investigation is concerned with a reviewof the present status of the field. Early optical surveys areconsidered, taking into account studies conducted by Hubble,investigations of the Magellanic Clouds, a catalog of H II regions inM31, and a survey of M101. Surveys carried out in recent years usingmore refined techniques have resulted in present knowledge ofsignificant numbers of H II regions in over 150 galaxies. Thecharacteristics of some large-scale surveys of H II regions whichinclude many galaxies studied by uniform techniques are discussed. It ispointed out that optical searches for H II regions in galaxies have beenalmost overwhelmingly successful. A total of 233 searched galaxies forwhich 16,293 H II regions have been mapped is presented in a table.

21-cm line profiles of 392 spiral galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1982A&AS...50..101B&db_key=AST

The Interaction of Galaxies and the Nature of Their Arms, Spanning Filaments and Tails. The Morphology of Galaxies. V.
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Observation and Astrometry data

Right ascension:10h53m24.10s
Aparent dimensions:3.388′ × 1.995′

Catalogs and designations:
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NGC 2000.0NGC 3447

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