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The Palermo Swift-BAT hard X-ray catalogue. II. Results after 39 months of sky survey
Aims: We present the Palermo Swift-BAT hard X-ray catalogueobtained from the analysis of data acquired during the first 39 monthsof the Swift mission. Methods: We developed a dedicated softwareto perform the data reduction, mosaicking, and source detection of theBAT survey data. We analyzed the BAT dataset in three energy bands(14-150 keV, 14-30 keV, 14-70 keV), obtaining a list of 962 detectionsabove a significance threshold of 4.8 standard deviations. Theidentification of the source counterparts was pursued using threestrategies: cross-correlation with published hard X-ray catalogues,analysis of field observations of soft X-ray instruments, andcross-correlation with SIMBAD databases. Results: The surveycovers 90% of the sky down to a flux limit of 2.5×10-11 erg cm-2 s-1 and 50% ofthe sky down to a flux limit of 1.8 ×10-11 ergcm-2 s-1 in the 14-150 keV band. We derived acatalogue of 754 identified sources, of which ˜69% areextragalactic, ˜27% are Galactic objects, and ˜4% arealready known X-ray or gamma ray emitters, whose nature has yet to bedetermined. The integrated flux of the extragalactic sample is ˜1%of the cosmic X-ray background in the 14-150 keV range.Table 2 is also available in electronic form 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/510/A48
| Kinematics of the Local Universe. XIII. 21-cm line measurements of 452 galaxies with the Nançay radiotelescope, JHK Tully-Fisher relation, and preliminary maps of the peculiar velocity field
Aims.This paper presents 452 new 21-cm neutral hydrogen linemeasurements carried out with the FORT receiver of the meridian transitNançay radiotelescope (NRT) in the period April 2003-March 2005. Methods: This observational programme is part of a larger projectaiming at an exhaustive and magnitude-complete HI extragalacticcatalogue for Tully-Fisher applications (the so-called KLUN project, forKinematics of the Local Universe studies, to end in 2008). The wholeon-line HI archive of the NRT today contains reduced HI-profiles for4500 spiral galaxies of declination δ > -40°(http://klun.obs-nancay.fr). Results: As an example of thisapplication, we used the direct Tully-Fisher relation in three (JHK)bands in deriving distances to a large catalogue of 3126 spiral galaxiesdistributed through the whole sky and sampling the radial velocity rangewell between 0 and 8000 km s-1. Thanks to an iterative methodaccounting for selection bias and smoothing effects, we show a detailedand original map of the velocity field in the Local Universe as apreliminary output.Data Tables [see full text], [see full text], and [see full text]and HI-profiles (Fig. [see full text]) are only available inelectronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/465/71
| Groups of Galaxies in the Two Micron All Sky Redshift Survey
We present the results of applying a percolation algorithm to theinitial release of the Two Micron All Sky Survey Extended SourceCatalog, using subsequently measured redshifts for almost all of thegalaxies with K<11.25 mag. This group catalog is based on the firstnear-IR all-sky flux-limited survey that is complete to|b|=5deg. We explore the dependence of the clustering on thelength and velocity scales involved. The paper describes a groupcatalog, complete to a limiting redshift of 104 kms-1, created by maximizing the number of groups containingthree or more members. A second catalog is also presented, created byrequiring a minimum density contrast of δρ/ρ>=80 toidentify groups. We identify known nearby clusters in the catalogs andcontrast the groups identified in the two catalogs. We examine andcompare the properties of the determined groups and verify that theresults are consistent with the UZC-SSRS2 and northern CfA redshiftsurvey group catalogs. The all-sky nature of the catalog will allow thedevelopment of a flow-field model based on the density field inferredfrom the estimated cluster masses.
| A catalogue of quasars and active nuclei: 12th edition
Aims.This catalogue is aimed at presenting a compilation of all knownAGN in a compact and convenient form and we hope that it will be usefulto all workers in this field.Methods.Like the eleventh edition, itincludes position and redshift as well as photometry (U, B, V) and 6 cmflux densities when available. We now give 20 cm rather than 11 cm fluxdensities.Results.The present version contains 85 221 quasars,1122 BL Lac objects and 21 737 active galaxies (including 9628 Seyfert1s), almost doubling the number listed in the 11th edition. We also givea list of all known lensed and double quasars.
| A Digital Archive of H I 21 Centimeter Line Spectra of Optically Targeted Galaxies
We present a homogeneous compilation of H I spectral parametersextracted from global 21 cm line spectra for some 9000 galaxies in thelocal universe (heliocentric velocity-200
| X-Ray Line-emitting Objects in XMM-Newton Observations: The Tip of the Iceberg
We present preliminary results from a novel search for X-rayline-emitting objects (XLEOs) in XMM-Newton images. Three sources havebeen detected in a test-run analysis of 13 XMM-Newton observations. Thethree objects found are most likely extremely absorbed active galacticnuclei characterized by a column density NH~1024cm-2. Their redshift has been directly determined from theX-ray data, by interpreting the detected emission line as the 6.4 keV Feline. The measured equivalent width of the X-ray line is, in all threecases, several keV. This pilot study demonstrates the success of oursearch method and implies that a large sample of XLEOs can be obtainedfrom the public XMM-Newton data archive.
| A Redshift Survey of Nearby Galaxy Groups: The Shape of the Mass Density Profile
We constrain the mass profile and orbital structure of nearby groups andclusters of galaxies. Our method yields the joint probabilitydistribution of the density slope n, the velocity anisotropy β, andthe turnover radius r0 for these systems. The measurementtechnique does not use results from N-body simulations as priors. Weincorporate 2419 new redshifts (included here) in the fields of 41systems of galaxies with z<0.04. The new groups have median velocitydispersion σ=360 km s-1. We also use 979 archivedredshifts in the fields of eight nearly relaxed clusters with z<0.1.Within R<~2r200, the data are consistent with a singlepower-law matter density distribution with slope n=1.8-2.2 for systemswith σ<470 km s-1 and n=1.6-2.0 for those withσ>470 (95% confidence). We show that a simple, scale-freephase-space distribution function (DF)f(E,L2)~(-E)α-1/2L-2β isconsistent with the data as long as the matter density has a cusp. Usingthis DF, matter density profiles with constant-density cores (n=0) areruled out with better than 99.7% confidence.
| The 2MASS-selected Flat Galaxy Catalog
An all-sky catalog of 18020 disc-like galaxies is presented. Thegalaxies are selected from the Extended Source Catalog of the Two MicronAll-Sky Survey (XSC 2MASS) basing on their 2MASS axial ratio a/b ≥ 3.The Catalog contains data on magnitudes of a galaxy in the J, H,KS bands, its axial ratio, positional angle, index ofluminosity concentration, as well as identification of the galaxy withthe LEDA and the NED databases. Unlike the available optical catalogs,the new 2MFGC catalog seems to be more suitable to study cosmicstreaming on a scale of z <~ 0.1. The dipole moment of distributionof the bright (K < 11m) 2MFGC objects (l = 227°, b =41° or SGL = 90°, SGB = -43°) lies within statistical errors(±15°) in the direction of the IRAS dipole and the opticalRFGC dipole.
| 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 hard medium survey with ASCA. III. a Type 2 AGN revealed from X-ray spectroscopy
In this paper we report the discovery of a hard X-ray selected Type 2Seyfert galaxy and we present and discuss its X-ray and optical spectrumtogether with the radio to X-ray energy distribution. The X-ray source -AXJ2254+1146 - is part of the ASCA Hard Serendipitous Survey (HSS). Whatmakes this discovery particularly noteworthy is the fact that the Type 2classification of this Seyfert galaxy has resulted directly from theX-ray data and has been confirmed by optical spectroscopy onlysubsequently. The X-ray spectrum of AXJ2254+1146 is best described by amodel consisting of an unresolved Gaussian line at 6.43+/- 0.1 keV plusthe so called ``leaky-absorber" continua having an intrinsic power lawphoton index of Gamma = 2.512.762.17 (1 sigmaconfidence interval). The best fit values of the absorbing columndensity (N_H = 1.852.241.47 x 1023cm-2), of the line equivalent width(0.60.840.36 keV) and of the scattering fraction(0.71.40.1%), lead us to classify it as a Type 2AGN from an X-ray point of view. Inspection of the POSS II image revealsthe presence, within the ASCA X-ray error circle, of the nearby Sbcspiral galaxy UGC 12237 (mB_o=14.26) that, even on positionalground considerations alone, is the most likely optical counterpart ofAXJ2254+1146. Subsequent optical spectroscopy of UGC 12237 has confirmedits Seyfert 2 optical nature. Based on observations performed at theEuropean Southern Observatory, Paranal, Chile
| 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.
| An Einstein X-Ray Survey of Optically Selected Galaxies. I. Data
We present the results of a complete Einstein imaging proportionalcounter X-ray survey of optically selected galaxies from theShapley-Ames Catalog, the Uppsala General Catalogue, and the EuropeanSouthern Observatory Catalog. Well-defined optical criteria are used toselect the galaxies, and X-ray fluxes are measured at the opticallydefined positions. The result is a comprehensive list of X-ray detectionand upper limit measurements for 1018 galaxies. Of these, 827 haveeither independent distance estimates or radial velocities. Associatedoptical, redshift, and distance data have been assembled for thesegalaxies, and their distances come from a combination of directlypredicted distances and those predicted from the Faber-Burstein GreatAttractor/Virgocentric infall model. The accuracy of the X-ray fluxeshas been checked in three different ways; all are consistent with thederived X-ray fluxes being of <=0.1 dex accuracy. In particular,there is agreement with previously published X-ray fluxes for galaxiesin common with a 1991 study by Roberts et al. and a 1992 study byFabbiano et al. The data presented here will be used in further studiesto characterize the X-ray output of galaxies of various morphologicaltypes and thus to enable the determination of the major sourcescontributing to the X-ray emission from galaxies.
| Extended LY alpha -absorbing Halos around Nearby Galaxies
In order to establish the Lyα absorption cross section ofpresent-day galaxies, we have identified 38 galaxies with z = 0-0.08that lie within 40-500 h^-1^ kpc of the line of sight to a QSO observedwith the Faint Object Spectrograph aboard the Hubble Space Telescope(HST). Including three galaxies in the field of 3C 273 investigated byprevious authors, we find that nine of 41 galaxies have associatedLyα absorption. If the identified Lyα absorption systems aregenuinely associated with the galaxies, then the covering factor of gasaround galaxies remains roughly constant at ~40% between 100 and 300h^-1^ kpc. Beyond 300 h^-1^ kpc, the incidence of absorption dropssharply. We conclude that (1) nearby galaxies do not possessLyα-absorbing halos beyond 300 h^-1^ kpc in radius and (2) thecovering factor of present-day galaxies between 50 and 300 h^-1^ kpc is44% at an equivalent width limit of W >= 0.3 A. For the nine galaxieswith associated Lyα absorption lines, differences in the galaxiessystemic velocities and the velocity of the absorption line, {DELTA}v,range over +/- 300 km s^-1^, consistent with the distribution found atredshifts > 0.1 by Lanzetta et al. and Le Brun, Bergeron, &Boisse. Values of {DELTA}v spanning several hundred km s^-1^ areprobably real for some of the QSO-galaxy pairs, however, and do notsimply arise from errors in measuring cz_gal_ or cz_abs_. This suggeststhat the absorbing clouds are kinematically tied to the galaxy disks andthat the distribution of {DELTA}v may arise because of the effects ofgalaxy inclination. We find no evidence for a correlation betweenLyα equivalent width and galaxy line-of-sight separation, whichweakens the argument that the identified galaxies are directlyassociated with the Lyα lines. Also, we find that absorption doesnot arise only from bright galaxies, since there are several examples inwhich low-luminosity galaxies apparently cause absorption. Yet we showthat the absorbing halos around galaxies cannot be independent of galaxyluminosity because if all low- redshift galaxies were surrounded byextended halos, the number of Lyα absorption systems found in HSTspectra would be much larger than has recently been determined. Thisresult leads us to question whether the galaxies are actuallyresponsible for the Lyα absorption lines or whether theassociation in redshift is fortuitous. Our results support the picturesuggested by others that Lyα lines arise in filaments or sheetsthat connect and contain the overdense regions that galaxies inhabit.This conclusion, however, remains at odds with the results of Lanzettaet al., who find that Lyα systems are more intimately linked withgalaxies. It may be, therefore, that we are seeing an evolution of theway in which Ly& lines associate with galaxies over the last fewbillion years. We suggest that at least some of the Lyα cloudsthat are not associated with galaxies at z ~ 0.5 have been slowlymerging with galaxies over time, creating larger but less uniform gasdistributions around the galaxies we see today.
| 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.
| KISO survey for ultraviolet-excess galaxies. XI
Charts of UV-excess galaxies detected on multicolor plates with the KisoSchmidt telescope are presented. A total of 10 survey field areconsidered. In a 300-sq-deg sky area, 460 objects are cataloged to aphotographic magnitude of about 18.
| A catalog of radio, optical, and infrared observations of spiral galaxies in clusters
The results of a major observational program on the luminosities,colors, and gas contents of spiral galaxies in clusters of galaxies arepresented. The data have been used as part of a detailed investigationinto the nature of cluster spirals and for revisions of the distancescale using the infrared Tully-Fisher relation. The observationalstrategies, reduction procedures, and sources or error are brieflydiscussed. The data include 21-cm H I observations, UBVR multiaperturephotometry, and H-band photometry of several hunderd spiral galaxies in10 clusters.
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