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The ISOPHOT 170 μm Serendipity Survey II. The catalog of optically identified galaxies%
The ISOPHOT Serendipity Sky Survey strip-scanning measurements covering≈15% of the far-infrared (FIR) sky at 170 μm were searched forcompact sources associated with optically identified galaxies. CompactSerendipity Survey sources with a high signal-to-noise ratio in at leasttwo ISOPHOT C200 detector pixels were selected that have a positionalassociation with a galaxy identification in the NED and/or Simbaddatabases and a galaxy counterpart visible on the Digitized Sky Surveyplates. A catalog with 170 μm fluxes for more than 1900 galaxies hasbeen established, 200 of which were measured several times. The faintest170 μm fluxes reach values just below 0.5 Jy, while the brightest,already somewhat extended galaxies have fluxes up to ≈600 Jy. For thevast majority of listed galaxies, the 170 μm fluxes were measured forthe first time. While most of the galaxies are spirals, about 70 of thesources are classified as ellipticals or lenticulars. This is the onlycurrently available large-scale galaxy catalog containing a sufficientnumber of sources with 170 μm fluxes to allow further statisticalstudies of various FIR properties.Based on observations with ISO, an ESA project with instruments fundedby ESA Member States (especially the PI countries: France, Germany, TheNetherlands and the UK) and with the participation of ISAS and NASA.Members of the Consortium on the ISOPHOT Serendipity Survey (CISS) areMPIA Heidelberg, ESA ISO SOC Villafranca, AIP Potsdam, IPAC Pasadena,Imperial College London.Full Table 4 and Table 6 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/422/39
| 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
| Correlations among Global Photometric Properties of Disk Galaxies
Using a two-dimensional galaxy image decomposition technique, we extractglobal bulge and disk parameters for a complete sample of early-typedisk galaxies in the near-infrared K band. We find significantcorrelation of the bulge parameter n with the central bulge surfacebrightness μb(0) and with effective radiusre. Using bivariate analysis techniques, we findthat logn, logre, and μb(0) are distributed ina plane with small scatter. We do not find a strong correlation of nwith bulge-to-disk luminosity ratio, contrary to earlier reports. Forthese early-type disk galaxies, re and the diskscale length rd are well correlated, but withlarge scatter. We examine the implications of our results for variousbulge formation scenarios in disk galaxies.
| 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.
| Near-infrared surface photometry of bulges and disks of spiral galaxies. The data
We present optical and near-infrared (NIR) surface brightness and colourprofiles, in bands ranging from U to K, for the disk and bulgecomponents of a complete sample of 30 nearby S0 to Sbc galaxies withinclinations larger than 50 deg. We describe in detail the observationsand the determination of colour parameters. Calibrated monochromatic andreal-colour images are presented, as well as colour index maps. Thisdata set, tailored for the study of the population characteristics ofgalaxy bulges, provides useful information on the colours of inner disksas well. In related papers, we have used them to quantify colourgradients in bulges, and age differentials between bulge and inner disk.
| Ages of Galaxies Bulges and Disks From Optical and Near-Infrared Colors
We compare optical and near-infrared colors of disks and bulges in adiameter-limited sample of inclined, bright, nearby, early-type spirals.Color profiles along wedge apertures at 15^deg^ from the major axis andon the minor axis on the side of the galaxy opposite to the dust laneare used to assign nominal colors for the inner disks (at 2 scalelength) and for the bulges (~0.5r_eff_), respectively. We estimate thatthe effects of dust reddening and the cross-talk between the colors ofthe two components is negligible. We find that color differences(bulge-disk) are very small: {DELTA}(U-R) = 0.126+/-0.165,{DELTA}(R-K)=0078+/-0.165. Disks tend to be bluer by an amount threetimes smaller than that reported by Bothun & Gregg [ApJ,350,73(1990)] for S0s. Color variations from galaxy to galaxy are muchlarger than color differences between disk and bulge in each galaxy.Probably, the underlying old population of disks and bulges is much moresimilar than the population paradigm would lead us to believe. Impliedage differences, assuming identical metallicities, are less than 30%.
| 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 Shape of the Luminosity Profiles of Bulges of Spiral Galaxies
Using a 2D generalization of Kent's model-independent decompositionmethod, we extract the K-band light profiles of the bulges of a sampleof field galaxies with morphological types ranging from S0 to Sbc. Wethen examine the shape of the bulge profiles, by means of fitting aseeing-convolved power law of the form μ(r) is proportional tor^1/n^, where the exponent n is allowed to vary. The best-fittingexponent n is found to vary systematically from values around 1(exponential) to 6 from late- to early- type bulges; the profiles tendto fall off more steeply in the outer parts for the later types. Thesame trend is seen as a function of bulge to disc ratio. Application ofthe method to artificial data proves that this result is not caused bydisc-light contamination. There are also indications that n becomeslarger with increasing total luminosity and radius of the bulge. Asimilar relation has recently been found for elliptical galaxies. Thesmooth trend of n with morphological type shows that the formation of orinteraction with the disc has affected the density distribution of thebulge.
| Colors and color gradients in bulges of galaxies
We have obtained surface photometry in U, B, R, and I for a completeoptically selected sample of 45 early-type spiral galaxies, toinvestigate the colors and color gradients of spiral bulges. Colorprofiles in U-R, B-R, U-B, and R-I have been determined in wedgesopening on the semiminor axes. Based on several criteria, like thesmoothness of the color profiles, the absence of dust lanes, and thecentral colors, we have defined a subsample of 18 objects whose colorsare largely unaffected by dust. We believe such colors are suitable forinferring properties of the stellar populations of bulges. We find thatthe colors of bulges are predominantly bluer than those of ellipticals.This result holds even when bulges are compared to ellipticals of thesame luminosity, and indicates that bulges are younger and/or more metalpoor than old elliptical galaxies. Most bulges do not reach solarmetallicities. Bulges show predominantly negative color gradients (blueroutward). For bright bulges (MBulgeR is less than-20.0), the magnitude of the gradient increases with bulge luminosity.For fainter bulges, gradients scatter around large negative values. Thebehavior of color gradients as a function of bulge luminosity suggestsdifferent formation mechanisms for faint and bright spheroids. Forbright bulges, the scaling of gradients with luminosity suggests aformation process involving dissipation. The similarity with ellipticalssuggests that the formation of the disk did not affect the stellarpopulations of the bulge in a major way. For small bulges (MRis greater than -20), the existence of pronounced color gradientssuggests a different formation mechanism. For these objects, thepresence of the disk may have severely affected the radial populationdistribution in the bulge.
| The 12 micron galaxy sample. I - Luminosity functions and a new complete active galaxy sample
An all-sky 12 micron flux-limited sample of active galaxies was selectedfrom the IRAS Point Source Catalog. Most of the sample galaxies are inexisting catalogs, and 99 percent have measured redshifts. The 12-micronand the far-infrared luminosity functions of active and normal galaxiesare derived using IRAS co-added data. A total of 22 percent of thesample galaxies harbor active nuclei. The sample consists almost equallyof Seyfert 1, Seyfert 2, and LINER nuclei. The derived luminosityfuctions for Seyfert 1 and Seyfert 2 galaxies are indistinguishable fromthose of the optically selected CfA sample. Thus, 12 micron selection isthe most efficient available technique for finding complete activegalaxy samples.
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