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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.
| Optically bright active galactic nuclei in the ROSAT-Faint source catalogue
To build a large, optically bright, X-ray selected AGN sample we havecorrelated the ROSAT-FSC catalogue of X-ray sources with the USNOcatalogue limited to objects brighter than O=16.5 and then with the APSdatabase. Each of the 3212 coincidences was classified using theslitless Hamburg spectra. 493 objects were found to be extended and 2719starlike. Using both the extended objects and the galaxies known frompublished catalogues we built up a sample of 185 galaxies withO_APS<17.0 mag, which are high-probability counterparts of RASS-FSCX-ray sources. 130 galaxies have a redshift from the literature and foranother 34 we obtained new spectra. The fraction of Seyfert galaxies inthis sample is 20%. To select a corresponding sample of 144high-probability counterparts among the starlike sources we searched forvery blue objects in an APS-based color-magnitude diagram. Forty-onewere already known AGN and for another 91 objects we obtained newspectra, yielding 42 new AGN, increasing their number in the sample to83. This confirms that surveys of bright QSOs are still significantlyincomplete. On the other hand we find that, at a flux limit of 0.02count s-1 and at this magnitude, only 40% of all QSOs aredetected by ROSAT.Tables 2, 3 and 4 are only available in electronic form athttp://www.edpsciences.org
| 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 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.
| Accurate positions of Zwicky galaxies. I
Accurate optical positions, obtained from POSS prints with the BolognaInstituto di Radioastronomia position measuring machine, are given for1007 galaxies in the 502-505, 519-523, 536-539 Zwicky Catalogue fieldsaround the Abnell cluster A 262 (0150 + 3555) region. The adoptedmeasurement procedure, with a precision of about one arcsec rms, isdiscussed, and the measurements are compared with previously obtainedpositions (Dressel and Condon, 1976). With a few exceptions, the averagedeviation of the absolute value of position is 4.5 arcsec in RA and 3.4arcsec in DEC.
| A 21 CM survey of the Pisces-Perseus supercluster. I - The declination zone +27.5 to +33.5 degrees
Neutral-hydrogen 21 cm line data for a sample of galaxies in the regionbounded by 22 h less than R.A. less than 04h, + 27 deg 30 arcmin Dec.less than + 33 deg 30 arcmin are presented as the first installment of asurvey of galaxies in the region of the Pisces-Perseus supercluster. Ofthe 415 galaxies observed in this strip with the Arecibo 305 mtelescope, 342 have been detached in the 21 cm line; another ten haveuseful upper limits to their H I content. The sample includes mostspiral, irregular, and dwarf galaxies larger than 1 arcmin; in selectedareas, spirals to a limiting magnitude of + 15.7 have been observed. Thevelocity distribution of the 511 galaxies with known redshift in thiszone deviates markedly from that expected for a similar sample ofrandomly placed objects. The region contains significant clustering inall three dimensions.
| 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.
| Double galaxy investigations. I - Observations
Redshift information from 240 A/mm spectrograms is presented for 370double arcsec galaxy systems from the Karachentsev (1972) catalog,including all pairs in that catalog with separation less than 80 arcsec.An extensive error discussion utilizing internal and external (21 cm)comparisons provides calibration of systematic error and determines theuncertainty for a typical high weight optical redshift to be plus orminus 65 km/sec. Internal differential redshifts within single spectrausing common lines achieve accuracies of 18-30 km/sec, depending uponseparation, and are available for about 200 pairs. Extensive informationon emission and other properties is also provided.
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