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NGC 2752


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Infrared Observations of Galaxies in the Local Universe. II. 391 Calibrated Images with Photometric and Structural Measurements
This paper presents empirical results from a deep imaging survey ofgalaxies in the local universe at the J and Ks wavelengths.Three hundred ninety-one images have been obtained and calibrated usingthe same camera and filter set with the Steward Observatory 1.6 m KuiperTelescope on Mount Bigelow and the 2.3 m Bok Telescope on Kitt Peak. Thelimiting magnitude is typically 22 mag arcsec-1 at J and 21mag arcsec-1 at Ks. The central surfacebrightness, apparent magnitudes, sizes, scale lengths, and inclinationsare tabulated from measurements made using these data. The purpose ofthis paper is to provide basic near-infrared data on a variety of galaxytypes.

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

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.

Infrared Observations of Galaxies in the Local Universe. I. The Survey and Some Representative Results
This paper introduces a continuing survey of galaxies in the localuniverse. Consistent deep images are being acquired for a representativesample of 321 galaxies in the Uppsala General Catalogue down to 21.7 magarcsec-2 at Ks (2.16 mu m) and 22.4 mag arcsec-2 at J (1.25 mu m) usinga NICMOS camera with a 3.'8 x 3.'8 field of view attached to the 61 inch(1.5 m) telescope on Mount Bigelow. We provide some examples of theresults being obtained by employing 64 deep images of a subset of 44galaxies. Bulge-to-disk ratios are tabulated for 30 galaxies. Thebrightness of the central region of 44 galaxies declines approximately 5mag from Hubble type S0 to Sm. An exponential vertical scale height atKs is found to be 500 pc for the disk of UGC 5173. Arm amplitudes offour nearly face-on spiral galaxies are found to range between 11% and88% compared to the interarm region. There is some evidence that the armamplitude is larger at Ks than it is at J. Color gradients are measuredfor 15 galaxies with only one showing a significant nonzero result. Ameasurement of galactic symmetry applied to 64 deep images reveals anaverage asymmetry of 7.6% ( sigma = 4.6%) for these galaxies.

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.

Magnetism in the local Virgo-centered supercluster of galaxies (radius about 24 Mpc)
The warp excess in nearby spiral galaxies is investigated as well as itsearlier interpretation in terms of a magnetic field on a distance scaleout to a redshift of 0.3 (out to 1200 Mpc, for H(0) = 75 km/s Mpc). Itis shown from a study of the rotation measure data as a function ofredshift that such a large scale is unwarranted, and that any warpexcess may be rather local and spurious with a small S/N of 1.7. It isinferred that a local intergalactic magnetic field must be less than 50microG. To facilitate studies on the local supercluster of galaxies, aVirgo-center supercluster coordinate system is proposed, where longitude0 deg goes through the center of the Virgo cluster of galaxies at thecenter of the local supercluster.

Magnetic fields in the Milky Way neighbourhood as deduced from WARPS in spiral galaxies
It is shown that warps of spiral galaxies are not randomly oriented inthe Milky Way neighborhood. By adopting a previous model, in which warpsare produced by intergalactic magnetic fields, and considering allNorthern Hemisphere warped edge-on NGC spiral galaxies, an analysis ofthe intergalactic magnetic field in the 100 Mpc neighborhood of theGalaxy is carried out. At the 100 Mpc scale the magnetic field is stillrather homogeneous, having a direction given by (alpha = 289 deg, delta= 8 deg), but a characteristic scale of about 25 Mpc is found, insidewhich the dispersion is very low. The region containing the VirgoCluster has a direction of the magnetic field different from thedirection found in adjacent regions.

Frequency of Warped Spiral Galaxies at Visible Wavelengths
A list of optical warped spiral galaxies with basic position andgeometrical parameters is presented. From this list an attempt todetermine the frequency of warped discs has been made. All northern NGChigh inclined spirals were examined in the Palomar Observatory SkySurvey. Warps were observed in about half of these galaxies, whichindicate that nearly all spiral galaxies are warped.

Statistical study of optical galactic WARPS
A list of northern spiral NGC galaxies, with inclinations higher than 74deg, and exhibiting warps have been obtained from the Palomar Sky Survey(POSS). Approximate position angles and 'warping angles' are given foreach galaxy, in order to have a first reference for statistical studiesof the warping phenomenon. When it is taken into account that warps arenot always observed (depending on their relative position with respectto the observer) the resulting frequency of warps was so high that atentative conclusion is that all disks are warped.

Periodicities in galaxy redshifts
Using new data for unassociated galaxies with wide H I profiles andvalues of period and solar motion predicted by Tifft and Cocke (1984), aperiodicity has been found which is significant at the conventional 5percent level. Together with Tifft's work on galaxy pairs and smallgroups, this result appears to provide evidence in favor of thehypothesis that measured galaxy redshifts occur in steps of a littlemore than 72 km/s or a simple multiple of this period.

CO in optically selected starburst galaxies
The results of a CO survey of optically selected starburst galaxies arepresented. CO emission was detected in nine of the 42 sample galaxies.The CO-to-blue luminosity ratio is nearly the same for this sample asfor previously detected field spirals. The CO-to-H I luminosity ratiofor starburst galaxies is perhaps a factor of 2.6 larger compared topreviously detected galaxies. The infrared-to-CO luminosity ratio instarburst galaxies is similar to that in isolated spirals, and smallerthan that in strongly interacting galaxies undergoing starbursts. Thesimilarity in global properties between Markarian starburst galaxies andnormal spirals suggests that the starbursts in optically selectedsamples of starburst galaxies occur over a much smaller region thaninfrared-selected samples.

A Study of the Largescale Structure in the Distribution of Galaxies in a Region Centered about the Cancer Cluster - Part Two - Further Observational Results
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986AJ.....91..732B&db_key=AST

Seven poor clusters of galaxies
The measurement of 83 new redshifts from galaxies in the region of sevenof the poor clusters of galaxies identified by Morgan et al (1975) andAlbert et al (1977) has been followed by an estimation of cluster massesthrough the application of both the virial theorem and the projected masmethod. For each system, these two estimates are consistent. For the twoclusters with highest X-ray luminosities, the line-of-sight velocitydispersions are about 700 km/sec, while for the five other clusters, thedispersions are of the order of less than about 370 km/sec. The D or cDgalaxy in each poor cluster is at the kinematic center of each system.

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NGC 2000.0NGC 2752
HYPERLEDA-IPGC 25523

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