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A sample of X-ray emitting normal galaxies from the BMW-HRI Catalogue
We obtained a sample of 143 normal galaxies with X-ray luminosity in therange 1038{-}1043 erg s-1 from thecross-correlation of the ROSAT HRI Brera Multi-scale Wavelet (BMW-HRI)Catalogue with the Lyon-Meudon Extragalactic Database (LEDA). We findthat the average X-ray properties of this sample are in good agreementwith those of other samples of galaxies in the literature. We selected acomplete flux limited serendipitous sample of 32 galaxies from which wederived the log N-log S distribution of normal galaxies in the fluxrange 1.1{-} 110 × 10-14 erg cm-2s-1. The resulting distribution is consistent with theEuclidean -1.5 slope. Comparisons with other samples, such as theExtended Medium Sensitivity Survey, the ROSAT All Sky Survey, theXMM-Newton/2dF survey, and the Chandra Deep Field Survey indicate thatthe log N -log S distribution of normal galaxies is consistent with aEuclidean slope over a flux range of about 6 decades.
| Principal component analysis of International Ultraviolet Explorer galaxy spectra
We analyse the UV spectral energy distribution of a sample of normalgalaxies listed in the International Ultraviolet Explorer (IUE) NewlyExtracted Spectra (INES) Guide No. 2 - Normal Galaxies using a principalcomponent analysis. The sample consists of the IUE short-wavelength (SW)spectra of the central regions of 118 galaxies, where the IUE apertureincluded more than 1 per cent of the galaxy size. The principalcomponents are associated with the main components observed in theultraviolet (UV) spectra of galaxies. The first component, accountingfor the largest source of diversity, may be associated with the UVcontinuum emission. The second component represents the UV contributionof an underlying evolved stellar population. The third component issensitive to the amount of activity in the central regions of galaxiesand measures the strength of star-formation events.In all the samples analysed here, the principal component representativeof star-forming activity accounts for a significant percentage of thevariance. The fractional contribution to the spectral energydistribution (SED) by the evolved stars and by the young population aresimilar.Projecting the SEDs on to their eigenspectra, we find that none of thecoefficients of the principal components can outline an internalcorrelation or can correlate with the optical morphological types. In asubsample of 43 galaxies, consisting of almost only compact and BCDgalaxies, the third principal component defines a sequence related tothe degree of starburst activity of the galaxy.
| 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
| Hot and Cold Gas in Early-Type Spirals: NGC 3623, NGC 2775, and NGC 1291
We have studied the distribution of cool, warm, and hot interstellarmatter in three of the nearest bright Sa galaxies. New X-ray data forNGC 1291, the object with the most prominent bulge, confirm earlierresults that the ISM in the bulge is dominated by hot gas. NGC 3623 hasa lesser amount of hot gas in the bulge but has both molecular gas andionized hydrogen in the central regions. NGC 2775 has the leastprominent bulge; its X-ray emission is consistent with an origin inX-ray binary stars, and there is a strict upper limit on the amount ofmolecular present in the bulge. All three galaxies have a ring ofneutral hydrogen in the disk. NGC 3623 and NGC 2775 each have inaddition a molecular ring coincident with the hydrogen ring. We concludethat even within the morphological class Sa there can be significantdifferences in the gas content of the bulge, with the more massivebulges being likely to contain hot, X-ray-emitting gas. We discuss thepossibility that the X-ray gas is part of a cooling flow in which coolgas is produced in the nucleus.
| 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 amorphous galaxy NGC 2777 - H I evidence for tidal interaction with a faint companion
NGC 2777 is an amorphous galaxy possessing the classic signature of anA-type spectrum with superposed emission lines. There is no opticalevidence for an interaction, but observations of the neutral hydrogen inthis system reveal an H I bridge between NGC 2777 and U3, a companionthat is 3 mag fainter. FIR observations indicate that the current rateof massive star formation in NGC 2777 is low, but the optical spectraindicate that it must have been significantly higher in the recent past.We were unable to detect CO in either galaxy. We also consider a sampleof 10 amorphous galaxies, all showing A-type absorption spectra: ninefrom the Revised Shapley-Ames Catalog, plus NGC 2777. All show optical/HI interaction and/or peculiar velocity fields, supporting the view thatamorphous characteristics are the result of interaction. For some of thegalaxies, the interacting companion is much fainter than the amorphoussystem, which indicates that previous concerns raised by the existenceof isolated amorphous galaxies may have been premature.
| 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.
| Large-Scale Structures in the Zone of Avoidance: The Galactic Anticenter Region
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJ...449..527L&db_key=AST
| Apparent magnitudes of galaxies behind the Milky Way
There are many Infrared Astronomy Satellite (IRAS) Uppsala GeneralCatalogue of Galaxies (UGC) and IRAS/Catalogue of Galaxies and ofClusters of Galaxies (CGCG) galaxies with measured redshifts in theMilky Way region at absolute value of b less than 15 deg. We compare themagnitudes of these galaxies with those of IRAS/UGC and IRAS/CGCGgalaxies located at b = 30 deg to 45 deg having similar redshift values.Eighteen redshifts of the latter objects were newly measured by us. Thebrightnesses of the galaxies systematically decrease with Galacticlatitude at the Milky Way region. It is shown that IRAS galaxies withincz less than 10000 km/sec are mostly detected in the regions behind theMilky Way with N(H I) less than 5 x 1021/sq cm if theredshifts are measured down to 21 mag in blue magnitude.
| An X-ray catalog and atlas of galaxies
An X-ray catalog and atlas of galaxies observed with the EinsteinObservatory imaging instruments (IPC and HRI) are presented. The catalogcomprises 493 galaxies, including targets of pointed observations, andRSA or RC2 galaxies serendipitously included in Einstein fields. A totalof 450 of these galaxies were imaged well within the instrumentalfields, resulting in 238 detections and 2123 sigma upper limits. Theother galaxies were either at the edge of the visible field of view orconfused with other X-ray sources. For these a rough measure of theirX-ray emission is also given. The atlas shows X-ray contour maps ofdetected galaxies superposed on optical photographs and givesazimuthally averaged surface brightness profiles of galaxies detectedwith a high signal-to-noise ratio.
| Radial velocities of galaxies in the neighborhood of groups of galaxies. III
New determinations of the radial velocities for 31 galaxies in theneighborhood of groups of galaxies are reported. The observations aredescribed, and data are given for the galaxies in a table, including thenumber of spectra used, the radial velocity of each galaxy corrected forthe motion of the sun and the earth, the internal error in themeasurement, estimates of the quality of the spectra, the spectral linesused in the calculation of the velocities, the radial velocitiesdetermined by other authors, and the membership of the objects ingalactic systems. The data from other authors are used to determine thereal (external) accuracy of the present determinations, and goodagreement is found.
| X-ray observations of peculiar galaxies with the Einstein Observatory
The results of X-ray observations with the Einstein Observatory of 33galaxies are presented. Almost all of these galaxies, some of which liein groups and in interactive pairs, display disturbed morphologies. Nouniform, well-defined selection criterion can describe the samplegalaxies, but almost all lie in a region of the optical color/colordiagram that suggests that they are experiencing bursts of starformation. This region is compatible with the locus of Markariangalaxies. The observed sample and the X-ray data are presented, and theX-ray data are discussed and compared with the optical and radioproperties of the galaxies. It is concluded that nuclear activity is notthe predominant source of X-rays in late-type peculiar galaxies and thatthe X-ray emission is likely to originate from the Population I galacticcomponent, in particular binary sources and possible young SNR's.
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