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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
| 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.
| The Dynamics of Poor Systems of Galaxies
We assemble and observe a sample of poor galaxy systems that is suitablefor testing N-body simulations of hierarchical clustering and otherdynamical halo models. We (1) determine the parameters of the densityprofile rho(r) and the velocity dispersion profile sigma_p(R), (2)separate emission-line galaxies from absorption-line galaxies, examiningthe model parameters and as a function of spectroscopic type, and (3)for the best-behaved subsample, constrain the velocity anisotropyparameter, beta, which determines the shapes of the galaxy orbits. Oursample consists of 20 systems, 12 of which have extended X-ray emissionin the ROSAT All-Sky Survey. We measure the 877 optical spectra ofgalaxies brighter than m_R~15.4 within 1.5 h^-1 Mpc of the systemcenters (we take H_0=100 h km s^-1 Mpc^-1). Thus, we sample the systemmembership to a radius typically three times larger than other recentoptical group surveys. The average system population is 30 galaxies, andthe average line-of-sight velocity dispersion is ~300 km s^-1. TheNavarro, Frenk, & White universal profile and the Hernquist modelboth provide good descriptions of the spatial data. In most cases anisothermal sphere is ruled out. Systems with declining sigma_p(R) arewell-matched by theoretical profiles in which the star-forming galaxieshave predominantly radial orbits (beta>0) many of these galaxies areprobably falling in for the first time. There is significant evidencefor spatial segregation of the spectroscopic classes regardless ofsigma_p(R).
| 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).
| 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.
| The reality of anomalous redshifts in the spectra of some QSOs and its implications.
The evidence for the physical association of close pairs involvingbright QSOs with large redshifts and bright nearby galaxies with smallredshifts, is reviewed and, in Table 1, a list of the best cases isgiven. It is shown that in a series of statistical studies usingcatalogs of QSOs and catalogs of galaxies, very strong correlations ofhigh redshift radio QSOs have been found successively with (o) [a.] TheShapley Ames Catalog of the brightest galaxies. Here the correlation iswith powerful radio QSOs with S>=9Jy (0.4GHz). The result issignificant at the 7-10σ level. (o) [b.] The Bright Galaxy Catalog(z<=0.05). Here the QSO sample is dominated by radio emitting QSOs,largely identified from the 3CR, Molonglo, Parkes, and 4C radiocatalogs. (o) [c.] The galaxies in the Lick Catalog (m<~17,z<~0.2). Again the sample of QSOs is a radio sample. (o) [d.] TheIRAS galaxy catalogs, where some fraction of the galaxies may have z upto 0.4, and where a few galaxies may be identical in position with theQSOs, but where the larger fraction have much smaller redshifts than theQSOs. Again the QSO sample is a radio sample. (o) [e.] Finally strongcorrelations on scales <~10' have been found between opticallybright, high redshift radio loud QSOs and the diffuse X-ray emissionseen by ROSAT. Bartelmann et al. (1994) believe that this diffuse X-rayemission is due to galaxy clusters at redshifts significantly less thanthe observed redshifts of the QSOs.
| Corrections and additions to the third reference catalogue of bright galaxies
List of corrections and additions to the Third Reference Catalogue ofBright Galaxies (RC3) are given. The corrected version of the catalogue(RC3.9b), dated April 1994, is currently available through the nationaldata centers.
| Properties of low-redshift QSO absorption systems - QSO-galaxy pairs
The chance proximity of QSOs and galaxies provides unique opportunitiesto probe the extent and content of gas in the foreground galaxiesthrough evaluation of the incidence and strength of absorption lines inthe spectra of the background QSOs. Recent results on the observedproperties of these low-redshift, heavy-element absorption systems aresummarized. These results are discussed in the context of the galaxymorphologies and environments and are briefly compared with Galacticabsorption and with the inferred properties of higher-redshift QSOabsorption systems.
| Redshifts and intrinsic time
We examine the hypothesis of the connection between quasars and galaxiesfrom the point of view of the theory of nonlinear dynamics of highlycomplex systems. It is found that complexity and nonlinearity of systemswhich are informationally disconnected may lead to different intrinsictime-scales of the systems. Systems with different intrinsic time-scalesage at different rates. This kind of aging can be measured by observingtheir different redshifts. On interpreting strongly differing redshiftsof astrophysically closely related objects as informational redshifts,we are in the position to determine their maturity ratios which aremeasures of the different nonlinear stages of the objects on thecosmological time-scale.
| Interstellar CA II in the galactic halo and in QSO absorption systems
The equivalent width distribution of Ca II K absorption lines seen inlines-of-sight through the galactic halo from an unbiased sample ofextragalactic sightlines is constructed, and the absorption by theinterstellar medium of the Galaxy is compared with that seen in thespectra of QSOs lying behind low-redshift galaxies. The Ca II absorptionseen in several QSO spectra apparently arises in material depositedinhomogeneously around the foreground galaxy, perhaps as a result ofearlier galaxy interactions or mergers. It is demonstrated that, forother QSO sightlines, such as those toward 0446 - 208 and 2020 - 370,the measured column densities of the absorbing gas can be reproduced byassuming that the quasar line-of-sight passes through the inclined diskof the intervening galaxy. In contrast, it is found that such a modelhas difficulty in explaining the nondetection of Ca II in the pair IC1746 - PHL 1226, and requires the diameter of the galaxy in theforeground of the quasar 1543 + 489 to be not less than 105/h kpc ifresponsible for the absorption. Since W-lambda(K) in the Galaxy iscorrelated with the number of components comprising the line, the largevalues of W-lambda(K) seen in most QSO-galaxy pairs can similarly beaccounted for by assuming that a line is composed of many individualabsorbers spread out over larger velocities than those found locally.This explanation is consistent with absorption attributed to a sightlinethrough an inclined disk.
| A survey of interstellar CA II absorption in the haloes of low-redshift galaxies
Results are reported from a search for Ca II absorption by the haloes ofgalaxies of redshift z less than 0.2 in the lines of sight to nine QSOs.Data obtained with the AAT or with the 2.5-m Isaac Newton Telescope atthe Observatorio del Roque de los Muchachos during 1986-1988 arecombined with previously published data and presented in tables, graphs,and sample spectra. The present observations detect no Ca II absorption,down to 2sigma limits of 38-164 mA in equivalent width, except in thecase of 1543 + 489. Analysis of previous observations which found Ca IIabsorption shows that it is confined to galactic disks orinhomogeneously distributed; i.e, present-day galaxies do not haveCa-absorbing spherical haloes with covering factor 1.
| Associations between quasi-stellar objects and galaxies
A table is presented here listing all close pairs of QSOs and galaxiesthat were found in a computer-aided search of catalogs of QSOs andbright galaxies and an extensive search of the literature. There is alarge excess of pairs with separations of 2 arcmin lor less, or about 60kpc, over the numbers expected if the configurations were accidental.The angular separation for 392 pairs adds to the evidence for physicalassociation, and it is shown that selection effects are not important. Ageneral rule is stated that QSOs tend to lie in the vicinity of normalgalaxies much more often than is expected by chance whether or not thegalaxies and the QSOs have the same redshifts. It is emphasized thatthis rule cannot be explained in terms of gravitational microlensing,and it is concluded that some part of the redshift of all classes ofactive nuclei is not associated with the expansion of the universe.
| CA II and NA I absorption in the QSO S4 0248 + 430 due to an intervening galaxy
Observations of the QSO S4 0248 + 430 and a nearby anonymous galaxy arepresented. Two absorption components are found in both Ca II H and K andNa I D1 and D2 at z(a) = 0.0515, 0.0523. Column densities of log N(CaII) = 13.29, 13.50, and log N(Na I) = 13.79, 14.18 are found for z(a) =0.0515, 0.0523 absorption systems, respectively. The column densityratios imply considerable calcium depletion and disk-type absorbing gas.At least one and possibly both absorption components are produced byhigh-velocity gas. A broadband image of the field shows an asymmetricalarmlike feature or possible tidal tail covering and extending past theposition of the QSO. The presence of this extended feature and theapparent difference between the absorption velocities and galaxyrotation velocity suggest that the absorbing gas is not ordinary diskgas, but rather is a result of tidal disruption.
| PHL 1226 and IC 1746 - A QSO-galaxy pair without CA II or NA I absorption
Spectroscopic observations of the QSO PHL 1226 show no absorption linesat the expected wavelengths of Ca II H and K and Na I D absorption atthe redshift of the nearby galaxy IC 1746 (z = 0.0176). The line ofsight to PHL 1226 intercepts IC 1746 near the galaxy major axis at aprojected separation from the galaxy nucleus of 28/h50 kpc. The 3-sigmaupper limits on equivalent width attained in the spectra are 110 mA forCa II H or K and 90 mA for either of the Na I D lines. The probable CaII K line reported by Bergeron et al. (1988) is not confirmed.
| PHL 1226-IC 1746: Another QSO-Galaxy Pair Without Ca II or Na I Absorption
Not Available
| Crowding on the sight line to the QSO PHL 1226 - The nearby galaxy IC 1746 and a galaxy cluster at Z = 0.16
Several galaxies adjacent to QSO PHL 1226, namely, a bright nearbygalaxy IC 1746 and a galaxy cluster at z = 16, were observed at the ESOwith the 3.6 m telescope and the Danish 1.5 m telescope, and at MaunaKea with the 3.6 m Canadian-French-Hawaiian Telescope. The results ofthe observations reveal that the IC 1746 galaxy is an edge-on spiralgalaxy 28/(50) kpc away from the line of sight at z = 0.01760 + or -0.0002. A weak Ca II K absorption line was detected in the QSO spectrumwhich is considered as having originated from the gaseous disc of IC1746. Two other galaxies, one at z = 0.1592 + or - 0.0020 and the otherat z = 0.1597 + or - 0.0010 were found to be only 24/h(50) kpc and41/h(50) kpc from the QSO line of sight, respectively. A strongsaturated Mg II absorption line doublet at z(abs) of about 0.1602 wasdiscovered in the QSO spectrum. It is believed that this Mg IIabsorption is associated with either of these galaxies.
| A search for QSOs in the fields of nearby galaxies. II - NGC 55, 253, 300 and 5364
The results of a search for QSOs in the fields of NGC 55, 253, 300, and5364, using low-dispersion objective-prism plates (obtained in 20-minexposures with the UK Schmidt Telescope Unit at Coonabarabran,Australia, during 1979-1982) and low-dispersion spectroscopy (obtainedusing the 1.9-m reflector at SAAO in August 1983), are reported. Data on12 candidate objects, of which nine are identified as QSOs with Bmagnitudes 16.1-18.6, are compiled in extensive tables and graphs andbriefly characterized; finding charts are provided.
| H I line studies of galaxies. III - Distance moduli of 822 disk galaxies
The distance scale established on the basis of a distance moduli catalog(for 822 galaxies) that was derived from 21-cm line widths via theB-band Tully-Fisher relation is compared with several independent scaleshaving a common zero point, that are based on the indicators forluminosity index, redshift, ring diameters, brightest superassociations,and effective diameters. These are in excellent systematic agreement,and confirm the linearity of the H I scale in the 24-35 modulusinterval, but indicate a small systematic zero point difference of about0.2 mag, which must be added to the H I moduli to place them on the same'short' distance scale defined by the others.
| 21-cm line profiles of 392 spiral galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1982A&AS...50..101B&db_key=AST
| Isophotal tracings of galaxies near quasars
Three cases where quasars fall close to large galaxies on the plane ofthe sky are investigated. In all three cases, disturbances in the innerisophotes of the galaxies are found. In all cases, the isophotaldisturbances are extended fairly closely in the direction of the quasarand could be interpreted as due to an event that occurred in the galaxyat a time of the order of 10 million years previously.
| Two new quasars near galaxies
A quasar of magnitude V = 19.2 and redshift z = 1.94 is reported at adistance of 1.6 minutes of arc from a galaxy whose apparent diameter isabout 2.0 minutes. A second quasar of magnitude V = 17.6 and redshift z= 0.71 is reported at a distance of 1.3 minutes from a galaxy whoseapparent diameter is about 1.5 minutes. Both quasars were discovered bynoticing blue stellar objects close to galaxies which were companions oflarger nearby galaxies.
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