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NGC 2616


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Везани чланци

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.

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.

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.

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.

Catalogue of unambiguous (Faraday-thin, one-component, spectrum-selected) rotation measures for galaxies and quasars
This all-sky catalogue of unambiguous rotation measure (from aFaraday-thin, one-component, spectrum selection) for 674 galaxies orquasars has been compiled, ordered, and edited from the availableliterature. All the known applications of the RM distribution towardforeground objects in the Galaxy (i.e., magnetic field in 4 nearbyspiral arms and in 4 nearby interstellar magnetic bubbles) have alsobeen catalogued.

Radio identifications of UGC galaxies - Starbursts and monsters
New and previously published observational data on galaxies withdeclination less than +82 deg from the Uppsala General Catalog (Nilson,1973) are compiled in extensive tables and characterized in detail.Optical positions are confirmed by measurement of Palomar Sky Survey Oprints, and radio identifications for 176 galaxies are made on the basisof 1.4-GHz Green Bank sky maps or 1.49-GHz observations obtained withthe C configuration of the VLA in November-December 1986; contour mapsbased on the latter observations are provided. Radio-selected andIR-selected galaxy populations are found to be similar (and distinctfrom optically selected populations), and three radio/IR criteria aredeveloped to distinguish galaxies powered by starbursts from those withsupermassive black holes or other 'monster' energy sources.

A VLBI survey at 2.29 GHz
VLBI observations at 2.29 GHz with fringe spacings of about 3milliarcsec have been performed on 1398 radio sources spread over theentire sky. 917 sources were detected, including 93 percent of theidentified BL Lacertae objects, 86 percent of the quasars, and 36percent of the galaxies. The resulting catalog of compact radio sourcesis useful for various astrophysical studies and in the formation of VLBIcelestial reference frames.

Magnetic field structure associated with the large 'Monogem' X-ray ring
The results of a search for evidence of the presence of an enhancedmagnetic field which might be associated with the giant, 20-deg-diameterMonogem ring in Gemini-Monoceros are reported. From polarizationobservations made earlier, the Faraday rotation measure is computed fordistant sources shining through the ring to compare with the distantsources along lines of sight adjacent to the ring. The rotation measuresare consistent with a shell model for the Monogem ring with a meanrotation measure of 25 rad/sq m above the surrounding background. This'magnetic bubble' is the fourth to be found near the sun, after theNorth Polar Spur, the Cetus Arc, and the Gum Nebula.

Optical spectroscopy of 28 southern radio galaxies
The results of an optical spectroscopic survey of 28 southern radiogalaxies including redshifts and descriptions of their spectra arepresented. One of these objects is a quasar, while five of the remainderinvolve fields where more than one galaxy has been observed because ofthe complex radio structure or uncertain identification. A Fleurssynthesis telescope map at 21 cm of PKS0114-47 and a VLA map at 6 cm ofPKS0843-33 are also presented and discussed.

A statistical VLBI study of milli-arcsecond cores in extragalactic radio sources
VLBI observations at 2.3 GHz with a baseline of approximately 8 x 10 tothe 7th wavelengths were performed on a complete sample of 103 sourcesfrom the Parkes + or - 4 deg catalog. Compact milli-arcsec cores werefound in 35 percent of all sources: in 80 percent of quasars, in 10percent of galaxies, and in 20 percent of empty field sources. It isshown that for quasars the percentage of the source flux density comingfrom milli-arcsec cores increased with increasing radio spectral index,radio variability, and optical redness. It is noted that quasars withextended radio structure (not less than approximately 10 arcsec) seemmore likely to have a detectable milli-arcsec core than do extendedradio galaxies. The absence of a strong correlation between quasarmilli-arcsec structure and redshift is found to be evidence for a lackof strong physical evolution in quasars.

Observations at 408 MHz of sources in the -4 to +4 deg declination strip of the Parkes 2700-MHz survey
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&AS...41...21G&db_key=AST

Accurate positions and identifications for a complete sample of 341 radio sources from the Parkes plus or minus 4 deg survey
Not Available

Intensity dependent radio spectral distributions in the Parkes 2700-MHz survey.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974AJ.....79..437C&db_key=AST

The Parkes 2700 MHz survey catalogues for the +/-4 declination zone and for selected regions.
Not Available

On the spectra of radio galaxies between 10 and 10 000 MHz.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971AJ.....76..970S&db_key=AST

Flux densities of radio galaxies at 8000 MHz.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971AJ.....76....1S&db_key=AST

A Determination of the Luminosity Function of Radiogalaxies at 400 and 2700 MHz
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971A&A....15...11M&db_key=AST

The Ohio Survey between 0 and -36 degrees .
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970AJ.....75..351E&db_key=AST

The Parkes catalogue of radio sources, declination zone 0° to -20°
Not Available

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Deклинација:-01°50'59.0"
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Каталог и designations:
Proper имена   (Edit)
NGC 2000.0NGC 2616
HYPERLEDA-IPGC 24129

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