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Correlations among multiwavelength luminosities of star-forming galaxies
It has been known for two decades that a tight correlation existsbetween global far-infrared (FIR) and radio continuum (1.4 and 4.8 GHz)fluxes/luminosities from star-forming galaxies, which may be explainedby formation activities of massive stars in these galaxies. For thisvery reason, a correlation might also exist between X-ray and FIR/radioglobal luminosities of galaxies. We analyse data from the ROSAT All-SkySurvey and from IRAS to show that such correlation does indeed existbetween FIR (42.5-122.5μm) and soft X-ray (0.1-2.4 keV) luminositiesLX and LFIR in 17 normal star-forming galaxies(NSFGs), including 16 late-type galaxies and one host-dominant Seyfertgalaxy, as well as in 14 active star-forming galaxies (ASFGs) consistingof starburst-dominant Seyfert galaxies. The quantitative difference insuch correlations in NSFGs and in ASFGs may be interpreted in terms ofevolutionary variations from classic starburst galaxies tostarburst-dominant Seyfert galaxies. Meanwhile, some low-luminosityactive galactic nuclei (LLAGNs) tend to exhibit such a correlation thatwe infer for star-forming galaxies, implying that star-formingactivities might be more dominant in LLAGNs. In contrast, AGN-dominantSeyfert galaxies do not show such a LX versus LFIRcorrelation; this is most likely related to accretions towardssupermassive black holes (SMBHs) in galactic nuclei. In order toestablish a physical connection between theLX-LFIR correlation and global star formation rate(SFR) in galaxies, we empirically derive bothLX-LB and LFIR-LB relationswith the blue-band luminosity LB roughly representing themass of a galaxy. It appears that the more massive galaxies are, themore star formation regions exist in these galaxies. The global SFR isnot only associated with the mass of a galaxy but also closely relatedto the level of star-forming activities therein. We propose a relationbetween soft X-ray luminosity and SFR in star-forming galaxies. In orderto probe the LX-LFIR relation, we construct anempirical model in which both FIR and X-ray emissions consist of twocomponents with one being closely associated with star formation and theother one not. Based on this model, we infer a linear relation betweenFIR/soft X-ray in star formation regions and radio luminosities, and geta linear relation between LX and LFIR forstar-forming regions.
| 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.
| ROSAT All-Sky Survey observations of IRAS galaxies. I. Soft X-ray and far-infrared properties
The 120 000 X-ray sources detected in the RASS II processing of theROSAT All-Sky Survey are correlated with the 14 315 IRAS galaxiesselected from the IRAS Point Source Catalogue: 372 IRAS galaxies showX-ray emission within a distance of 100 arcsec from the infraredposition. By inspecting the structure of the X-ray emission in overlayson optical images we quantify the likelihood that the X-rays originatefrom the IRAS galaxy. For 197 objects the soft X-ray emission is verylikely associated with the IRAS galaxy. Their soft X-ray properties aredetermined and compared with their far-infrared emission. X-ray contourplots overlaid on Palomar Digitized Sky Survey images are given for eachof the 372 potential identifications. All images and tables displayedhere are also available in electronic form.
| 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.
| Galaxy structures in the Hercules region
216 redshifts have been obtained in a region of 981 sq deg south of theHercules supercluster. 172 of these redshifts are of galaxies withmpg less than or equal to 15.1, 110 of which had no previousvelocity measurement. 44 new redshifts are of galaxies fainter thanmpg = 15.1. With these new data we have been able to define asample in a vast region (approximately 1700 sq deg) around Herculeslimited to mpg less than or equal to 15.1 with a velocitycompleteness of 81.5%. 189 galaxies have been morphologically classifiedso that all galaxies in the sample with known velocity now also haveknown morphology. The magnitude limited sample, including 556 galaxies,is then used to identify and describe galaxy structures in the region.We find that the overdense volume is small, that its overall appearanceis that of a coral branch floating in a sea of nothing and that earlyand late type galaxies defined different structures.
| The far-infrared properties of the CfA galaxy sample. I - The catalog
IRAS flux densities are presented for all galaxies in the Center forAstrophysics magnitude-limited sample (mB not greater than 14.5)detected in the IRAS Faint Source Survey (FSS), a total of 1544galaxies. The detection rate in the FSS is slightly larger than in thePSC for the long-wavelength 60- and 100-micron bands, but improves by afactor of about 3 or more for the short wavelength 12- and 25-micronbands. This optically selected sample consists of galaxies which are, onaverage, much less IR-active than galaxies in IR-selected samples. Itpossesses accurate and complete redshift, morphological, and magnitudeinformation, along with observations at other wavelengths.
| Probes of large-scale structure in the Corona Borealis region
The present redshift survey of the Corona Borealis region encompassesredshifts, magnitudes and positions for 83 galaxies covering a 16.4 sqdeg region; a complementary survey covers 39.2 sq deg, is complete tom(B)0 of 15.5, and encompasses 37 galaxies. The combined surveyfurnishes further support for the 'bubble-like' geometry revealed by theshallower CfA survey. The redshift distribution obtained is noted to bevery similar to that in the neighboring Bootes region. The structure ofvoids and surfaces in the galaxy distribution is insensitive toluminosity for M(B)0 of less than about -17.4.
| A survey of galaxy redshifts. IV - The data
The complete list of the best available radial velocities for the 2401galaxies in the merged Zwicky-Nilson catalog brighter than 14.5mz and with b (II) above +40 deg or below -30 deg ispresented. Almost 60 percent of the redshifts are from the CfA surveyand are accurate to typically 35 km/s.
| Accurate Optical Positions of Arakelian Galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1981AJ.....86..820K&db_key=AST
| Galaxies of high surface brightness
Two lists are presented which contain 621 galaxies whose surfacebrightness, as derived from their apparent magnitudes, is at least 22.0magnitudes from an area of 1 sq arcsec. The lists were compiled in anattempt to verify observationally a possible correlation between surfacebrightness and nuclear activity. Four percent of all the galaxies in anarea of 4.5 sr at declinations higher than -3 deg and galactic latitudesgreater than 20 deg are listed, including 30 Markarian, 29 Zwicky, and 7blue Haro galaxies. A morphological study of 130 of the galaxiesindicates that about half are elliptical or lenticular, 50 are compactor peculiar, and that there is an excess of elliptical and lenticularobjects in comparison with a random sample. Notes on the morphologicaltypes and colors of the galaxies are provided along with identificationcharts.
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