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A new list of extra-galactic radio jets
A catalogue of extra-galactic jets is very useful both in observationaland theoretical studies of active galaxies. With the use of new powerfulradio instruments, the detailed structures of very compact or weak radiosources are investigated observationally and many new radio jets aredetected. In this paper, we give a list of 661 radio sources withdetected radio jets known to us prior to the end of December 2000. Allreferences are collected for the observations of jets in radio, IR,optical, UV and X-ray wave-bands. Table 1 and references to Table 1 areonly available in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr ( or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/381/757

Galaxy coordinates. II. Accurate equatorial coordinates for 17298 galaxies
Using images of the Digitized Sky Survey we measured coodinates for17298 galaxies having poorly defined coordinates. As a control, wemeasured with the same method 1522 galaxies having accurate coordinates.The comparison with our own measurements shows that the accuracy of themethod is about 6 arcsec on each axis (RA and DEC).

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.

The First Caltech--Jodrell Bank VLBI Survey. I. lambda = 18 Centimeter Observations of 87 Sources
We present the first results from the first Caltech-Jodrell Bank VLBIsurvey (the CJ1 survey). The CJ1 sample includes 135 radio sources withtotal flux density 1.3 Jy > S_6 cm_ => 0.7 Jy, declination δ=> 35^deg^, and Galactic latitude |b^II^| > 10^deg^. It extendsthe flux density limit of the complete "PR" sample studied by Pearson& Readhead from 1.3 to 0:7 Jy and increases the total number ofsources from 65 to 200. The complete survey includes VLBI images at bothλ- 18 and 6 cm of all the objects in the extended sample thathave cores strong enough to be mapped with the Mark II VLBI system.These images provide a large enough sample to study, for example, thevariety of morphologies exhibited by compact radio sources, cosmologicalevolution, superluminal motion, and misalignment between parsec-scaleand kiloparsec-scale radio structures. In this paper we presentλ-18 cm VLBI observations of 56 CJ1 and 3l PR sources made in1990-1991, including images of 82 sources. The observations were madewith a "snapshot" technique in which each source was observed in three20-30-minute scans using an array of 12-16 antennas. The images haveresolution 3-10 mas and dynamic range greater than 100:1. later papersin the series will present the remaining λ-18 cm observations,the λ-6 cm observations, and the analysis and interpretation ofthe results.

The cluster environments of powerful radio galaxies
Results in the form of the ratio of the spatial cross-correlationamplitude to the autocorrelation amplitude are given as estimates of thelocal galaxy density around about 200 powerful radio sources. Lickgalaxy counts for z of less than 0.1 are extended to z of less than 0.25using deep galaxy samples from UK Schmidt plates. Although thelow-luminosity Fanaroff-Riley class I sources lie in richer clustersthan those of class II, a real scatter in properties is found. Theresults show no statistical evidence for the difference in environmentsuggested to exist between different subclasses of the class II sources.Compact radio sources are found to lie in regions of low galacticdensity.

Decametric survey of discrete sources in the northern sky. X Spectra of some radio sources in the frequency range 12.6-1415 MHz for declinations 52 to 60 deg
The data of the latest decametric band survey performed with the UTR-2radio telescope are used along with other results obtained at higherfrequencies (below 1415 MHz) for plotting spectra of 114 radio sourceslocated in a sky strip between declinations 52° and60°. Some parameters of the source spectra in the frequencyrange 12.6-1415 MHz are presented

Decametric survey of discrete sources in the northern sky. IX - Source catalogue in the declination range 52 deg to 60 deg
Some results of a systematic survey of radio sources to the north ofdeclination -13 deg carried out with the UTR-2 radio-telescope duringthe period from 1979 to 1982 which coincided with the maximum of the11-yr solar cycle are presented. The data presented include: apparentcoordinates and fluxes of radio sources at 10, 12.6, 14.7, 16.7, 20, and25 MHz and errors; total number of observations at each frequency usedto obtain the estimates; number of inclinations of the telescope beamalong the hour angle coordinates at which the radio-source was observed;averaged values of the source positions and the fluxes at themiddle-frequency of the UTR-2 as obtained from the measured spectrum ofthe source in the range 12.6-25 MHz; spectral index and error thereof;and radio and optical identification.

A correlation between ellipticity and core-strength in extended radio galaxies
It is shown that in the case of extended radio sources a correlationexists between the fraction of the radio flux retained in the corecomponent and the ellipticity of the underlying galaxy. The correlationis in the sense that stronger cores occur in flatter galaxies. It wouldseem that there exists a class of intrinsically rounder, redder, massiveellipticals with larger velocity dispersions and metallicities, that canform extended radio sources more efficiently. Thus the occurrence of aradio source appears to be related to the dynamical and chemicalevolution of the Galaxy.

Are there correlations between radio and optical axes of radio galaxies
The relative orientations of radio and optical axes of radio galaxieshave been examined on the basis of combined material from several smallsamples. Rotation axes of some radio galaxies have been redeterminedassuming that the published measurements refer to rotational motionsonly. It is found that the rotation axis is quite different from thoseprevious determinations, where rotation-expansion models were used. Inparticular, the correlation between radio source axes and rotation axesdisappears when the allowance for expansion is dropped. No statisticallysignificant correlation between optical major axes of the galaxay imageand radio source axes is found when all existing measurements, notexceeding 140, are combined.

Extended radio sources and elliptical galaxies. III - Optical positions for galaxy centers
Optical positions measured with an accuracy to within about 0.4 arcsecare presented for the centers of 87 elliptical and S0 galaxiesidentifiable with radio sources that have been mapped either with theNRAO four-element interferometer at 2.7 and 8.1 GHz or with VLA antennasat 4.9 GHz. The optical measuring procedure is outlined, and the opticalpositions are given along with approximate apparent magnitudes and briefdescriptions of other objects in some of the fields. Fiftyidentifications are made on the basis of coincidence between asmall-diameter component in the radio source and the optical center of agalaxy. The reliability of the remaining identifications is evaluated inthe light of previously established reliability criteria.

The 5 GHz strong source surveys. IV - Survey of the area between declination 35 and 70 degrees and summary of source counts, spectra and optical identifications
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978AJ.....83..451P&db_key=AST

Variability of extragalactic sources at 2.7 GHz. II - Flux densities of 550 sources and further evidence for variations
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977AJ.....82...21B&db_key=AST

Atlas of interacting galaxies, Part. II and the concept of fragmentation of galaxies.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...28....1V&db_key=AST

Optical identification of radio sources using accurate radio and optical positions. II
Results of optical-position measurements are given for 321 objectswithin 10 arcsec (sometimes more) of 267 radio-source positions. A totalof 137 QSO and QSO-like identification plus 57 galaxy identificationsare suggested on the basis of position agreement between thesecond-of-arc radio positions and optical positions measured to about0.4 arcsec. Apparent V magnitudes, position errors, and information onmorphology, color, and previous identifications are also provided. Thereliability of the identification is evaluated, the number of chancecoincidence is estimated, and distributions of radio-minus-opticalposition differences are plotted for the various object types. About 10neutral stellar objects and red stellar objects, some of which may becompact galaxies, are included in the QSO and QSO-like identifications;the galaxy identifications include faint red objects that should proveuseful in studies of galactic evolution and the Hubble diagram. It isshown that the number of faint red and neutral stellar objects is notsufficient to explain the observed maximum in the QSO apparent-magnitudedistribution as an observational selection bias against faint QSOs butthat this effect can be explained in terms of a statistical relationbetween QSO radio and optical luminosities.

First results from the Texas interferometer: positions of 605 discrete sources.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973AJ.....78....1D&db_key=AST

A pencil-beam survey of radio sources at 178 MHz
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969MNRAS.145..181C&db_key=AST

Identifications of radio sources with bright galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1967MNRAS.135..231C&db_key=AST

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Observation and Astrometry data

Constellation:Ursa Major
Right ascension:08h47m52.90s
Aparent dimensions:1.514′ × 1.514′

Catalogs and designations:
Proper Names   (Edit)
NGC 2000.0NGC 2656

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