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A new sample of large angular size radio galaxies. III. Statistics and evolution of the grown population
We present in this paper a detailed study of a new sample of largeangular size FR I and FR II radio galaxies and compare the properties ofthe two classes. As expected, a pure morphology based distinction of FRIs and FR IIs corresponds to a break in total radio power. The radiocores in FR Is are also weaker than in FR IIs, although there is not awell defined break power. We find that asymmetry in the structure of thesample members must be the consequence of anisotropies in the mediumwhere the lobes expand, with orientation playing a minor role. Moreover,literature data and our observations at kiloparsec scales suggest thatthe large differences between the structures of FR I and FR II radiogalaxies must arise from the poorly known central kiloparsec region oftheir host galaxies. We analyze the sub-sample of giant radio galaxies,and do not find evidence that these large objects require higher corepowers. Our results are consistent with giant radio galaxies being theolder population of normal FR I and FR II objects evolving in lowdensity environments. Comparing results from our sample with predictionsfrom the radio luminosity function we find no evidence of a possible FRII to FR I evolution. Moreover, we conclude that at z 0.1, one outof four FR II radio sources has a linear size above 500 kpc, thus beingin an advanced stage of evolution (for example, older than 10 Myrassuming a jet-head velocity of 0.1c). Radio activity seems to be ashort-lived process in active galaxies, although in some casesrecurrent: five objects in our sample present signs of reactivation intheir radio structures.
| Redshift-Distance Survey of Early-Type Galaxies: Spectroscopic Data
We present central velocity dispersions and Mg2 line indicesfor an all-sky sample of ~1178 elliptical and S0 galaxies, of which 984had no previous measures. This sample contains the largest set ofhomogeneous spectroscopic data for a uniform sample of ellipticalgalaxies in the nearby universe. These galaxies were observed as part ofthe ENEAR project, designed to study the peculiar motions and internalproperties of the local early-type galaxies. Using 523 repeatedobservations of 317 galaxies obtained during different runs, the dataare brought to a common zero point. These multiple observations, takenduring the many runs and different instrumental setups employed for thisproject, are used to derive statistical corrections to the data and arefound to be relatively small, typically <~5% of the velocitydispersion and 0.01 mag in the Mg2 line strength. Typicalerrors are about 8% in velocity dispersion and 0.01 mag inMg2, in good agreement with values published elsewhere.
| Redshift-Distance Survey of Early-Type Galaxies: Circular-Aperture Photometry
We present R-band CCD photometry for 1332 early-type galaxies, observedas part of the ENEAR survey of peculiar motions using early-typegalaxies in the nearby universe. Circular apertures are used to tracethe surface brightness profiles, which are then fitted by atwo-component bulge-disk model. From the fits, we obtain the structuralparameters required to estimate galaxy distances using theDn-σ and fundamental plane relations. We find thatabout 12% of the galaxies are well represented by a pure r1/4law, while 87% are best fitted by a two-component model. There are 356repeated observations of 257 galaxies obtained during different runsthat are used to derive statistical corrections and bring the data to acommon system. We also use these repeated observations to estimate ourinternal errors. The accuracy of our measurements are tested by thecomparison of 354 galaxies in common with other authors. Typical errorsin our measurements are 0.011 dex for logDn, 0.064 dex forlogre, 0.086 mag arcsec-2 for<μe>, and 0.09 for mRC,comparable to those estimated by other authors. The photometric datareported here represent one of the largest high-quality and uniformall-sky samples currently available for early-type galaxies in thenearby universe, especially suitable for peculiar motion studies.Based on observations at Cerro Tololo Inter-American Observatory (CTIO),National Optical Astronomy Observatory, which is operated by theAssociation of Universities for Research in Astronomy, Inc., undercooperative agreement with the National Science Foundation (NSF);European Southern Observatory (ESO); Fred Lawrence Whipple Observatory(FLWO); and the MDM Observatory on Kitt Peak.
| A new catalogue of ISM content of normal galaxies
We have compiled a catalogue of the gas content for a sample of 1916galaxies, considered to be a fair representation of ``normality''. Thedefinition of a ``normal'' galaxy adopted in this work implies that wehave purposely excluded from the catalogue galaxies having distortedmorphology (such as interaction bridges, tails or lopsidedness) and/orany signature of peculiar kinematics (such as polar rings,counterrotating disks or other decoupled components). In contrast, wehave included systems hosting active galactic nuclei (AGN) in thecatalogue. This catalogue revises previous compendia on the ISM contentof galaxies published by \citet{bregman} and \citet{casoli}, andcompiles data available in the literature from several small samples ofgalaxies. Masses for warm dust, atomic and molecular gas, as well asX-ray luminosities have been converted to a uniform distance scale takenfrom the Catalogue of Principal Galaxies (PGC). We have used twodifferent normalization factors to explore the variation of the gascontent along the Hubble sequence: the blue luminosity (LB)and the square of linear diameter (D225). Ourcatalogue significantly improves the statistics of previous referencecatalogues and can be used in future studies to define a template ISMcontent for ``normal'' galaxies along the Hubble sequence. The cataloguecan be accessed on-line and is also available at the Centre desDonnées Stellaires (CDS).The catalogue is available in electronic form athttp://dipastro.pd.astro.it/galletta/ismcat and at the CDS via anonymousftp to\ cdsarc.u-strasbg.fr (130.79.128.5) or via\http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/405/5
| A new sample of large angular size radio galaxies. II. The optical data
We constructed and presented in the first paper of this series a newsample of 84 large angular size radio galaxies by selecting from theNRAO VLA Sky Survey objects with angular size >=4arcmin , declinationabove +60deg and total flux density at 1.4 GHz >= 100 mJy.In this paper we present optical spectra and images of those galaxiesassociated with the radio emission for which no redshift was known priorto our observations. Optical counterparts have been identified for all(but one) members of the sample. After our observations, a reliablespectroscopic redshift is available for 67 objects (80%) from thesample. This paper, the second of a series of three, contributes toincrease the number of well-defined samples of radio galaxies with amplespectroscopic information.
| A new sample of large angular size radio galaxies. I. The radio data
We present a new sample of 84 large angular size radio galaxies selectedfrom the NRAO VLA Sky Survey. Radio sources with declination above+60deg, total flux density greater than 100 mJy at 1.4 GHzand angular size larger than 4arcmin have been selected and observedwith the VLA at 1.4 and 4.9 GHz. The radio observations attempt toconfirm the large angular size sources and to isolate the core emissionfor optical identification. In this paper, the first of a series ofthree, we present radio maps of 79 sources from the sample and discussthe effects of the selection criteria in the final sample. 37 radiogalaxies belong to the class of giants, of which 22 are reported in thispaper for the first time. Complete Fig.~2 is only available inelectronic form at http://www.edpsciences.org
| 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.
| 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.
| Spectroscopy of 1 Jy and S5 radio source identifications. II
Low resolution spectroscopy of the optical counterparts is reported fora total of 35 radio sources from the 1 Jy and S5 catalog. We present 24new redshifts, confirm 2 uncertain redshifts and give spectroscopic datafor 6 additional objects with previously known redshifts. While two ofthe remaining sources turned out to be BL Lac objects showingfeatureless spectra, the proposed counterpart of one radio source wasfound to be a galactic star. The correct identification of the latter isa nearby QSO.
| A compendium of radio spectra and luminosities for three complete samples of radio sources
A complete sample of powerful extragalactic radio sources comprising 256objects is defined. Fits to their radio spectra are presented andluminosities and spectral indices of these objects are derived atstandard rest frequencies as well as bolometric luminosities betweememitted frequencies of 10 MHz and 100 GHz.
| The large-scale clustering of radio galaxies
An all-sky sample of radio galaxies at redshifts equal to or less than0.1 is used to study clustering in the universe on scales up to severalhundred Mpc. The two-point correlation function for these galaxies isconsistent with their high optical luminosity and location in moderatelyrich environment. Direct methods for obtaining the power spectrum of thedensity field traced by the radio galaxies are discussed taking intoaccount the selection function of the sample. The results of thepower-spectrum analysis indicate that the distribution of radio galaxiesis more uniform on very large scales than would be predicted from anextrapolation of the power-law clustering found on small scales.
| UGC galaxies stronger than 25 mJy at 4.85 GHz
UGC galaxies in the declination band +5 to +75 deg were identified byposition coincidence with radio sources stronger than 25 mJy on theGreen Bank 4.85 GHz sky maps. Candidate identifications were confirmedor rejected with the aid of published aperture-synthesis maps and new4.86 GHz VLA maps having 15 or 18 arcsec resolution, resulting in asample of 347 nearby radio galaxies plus five new quasar-galaxy pairs.The radio energy sources in UGC galaxies were classified as 'starbursts'or 'monsters' on the basis of their infrared-radio flux ratios, infraredspectral indices, and radio morphologies. The rms scatter in thelogarithmic infrared-radio ratio q is not more than 0.16 for starburstgalaxies selected at 4.85 GHz. Radio spectral indices were obtained fornearly all of the UGC galaxies, and S0 galaxies account for adisproportionate share of the compact flat-spectrum (alpha less than0.5) radio sources. The extended radio jets and lobes produced bymonsters are preferentially, but not exclusively, aligned within about30 deg of the optical minor axes of their host galaxies. The tendencytoward minor-axis ejection appears to be independent of radio-sourcesize and is strongest for elliptical galaxies.
| 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.
| 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.
| Spectroscopy and photometry of elliptical galaxies. III - UBV aperture photometry, CCD photometry, and magnitude-related parameters
Photoelectric aperture photometry of nearly 2000 individual observationsof 449 elliptical galaxies combined with published measurements usingthe self-consistent UVB color catalog developed by Burstein et al.(1987) are presented. The data are placed on a standard magnitude andcolor system, and 'total' magnitudes and effective diameters are derivedby comparison with the standard elliptical magnitude growth curve. Agraphical representation of the standard growth curve and the residualsfrom it for each galaxy are given, and a new diameter measurement Dn ispresented which can be measured reliably for elliptical galaxies andserves as an accurate distance indicator when combined with centralvelocity dispersion. Individual magnitudes, surface brightnesses,effective diameters, and values of Dn are summarized for each galaxy incatalog form.
| 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.
| Variations of the linear sizes of extragalactic radio sources with radio luminosity and redshift
The variations with radio luminosity and redshift of the characteristiclinear size of extragalactic radio sources are investigated in two ways:(1) by examining bright flux-density-limited samples in order todetermine the dependence explicitly, and (2) by comparing angularsize-flux density data from faint samples (which generally have noredshift information) with numerical predictions, using individualsources in bright samples to define the local population. Thesepredictions, using multi-frequency space-density evolution models,divide the total population into flat- and steep-spectrum components,thereby allowing populations found at different frequencies to berelated. These investigations suggest that the apparent localdistribution of linear sizes is determined by instrumental and physicalselection effects which result in a weak inverse correlation of linearsize with radio luminosity. For populations at earlier cosmologicalepochs, these effects cause an apparent decrease in linear size withredshift, although not by enough to account for the observationalresults. These may thus point to a variation in the relative proportionsof physically distinct types of source with redshift.
| 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.
| Bright extragalactic radio sources at 2.7 GHz. II - Observations with the Cambridge 5-km telescope
Observations are presented of 51 radio sources, of which only nine wereresolved, at 2.7 GHz. The large number of unresolved sources in thesample are not all, as is commonly supposed, flat-spectrum objects, andinclude 44% having steep high-frequency spectra which cannot beclassified as either extended radio sources or cm-excess compactobjects. No evidence is found that the arcsec structure or cosmologicalbehavior of these compact steep-spectrum sources differs from that ofthe flat-spectrum sources. Grounds are considered for regarding thecompact steep-spectrum sources as more closely related to extendedsources than to compact flat-spectrum sources.
| Bright extragalactic radio sources at 2.7 GHz. I - The Northern Hemisphere catalogue
This paper presents a complete sample of 168 radio sources, defined at2.7 GHz and comprising the brightest sources from the high-frequencysurveys made at ANRAO/Parkes, NRAO/Greenbank and MPIfR/Bonn. The sampleis complete to S2.7 = 1.5 Jy over an area of 4.05 sr for which delta isgreater than 10 deg and /b/ is greater than 10 deg. All members of thesample have been observed with the Cambridge 5-km telescope. The samplecontains similar numbers of resolved and unresolved sources; the latterare usually the 'flat-spectrum' objects which are poorly represented inlow-frequency surveys. Of the 168 members, 156 (93 per cent) haveoptical identifications, while 108 (64 per cent) have measuredredshifts. Brief discussions of morphologies, spectra, luminosities, andsource counts are given.
| Extended radio sources and elliptical galaxies. I - Small-diameter components in extended structures. II - A search for radio cores using the VLA
These papers report high-resolution observations of several hundredradio galaxies with the NRAO interferometer at 2.7 and 8.1 GHz and withthe VLA at 4.9 GHz. The observations were performed to study therelation between the gross features of extended radio galaxies and theirorientation relative to their parent optical objects as well as thecurrent activity of the galaxies as evidenced by radio emission withintheir optical boundaries. First, results are presented for 48 extendedradio galaxies at declinations greater than +15 deg in whichsmall-diameter (less than 3 arcsec) components were detected. Radio dataare provided for the small-diameter cores and the extended emissioncontaining them, the resulting optical identifications of 44 extendedstructures are described, and the physical properties of the smallcomponents are analyzed. Implications are discussed for identificationsof extended sources lacking detectable small-diameter components.Further observations with the VLA at 4.9 GHz are then reported whichwere made to improve the reliability of the identifications of 21 radiosources by detecting radio cores in the nuclei of the parent galaxies.Problems involved in the identification of extended radio sources areoutlined.
| 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
| 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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