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Searching for X-Ray Luminous Starburst Galaxies
The existence or otherwise of X-ray luminous star-forming galaxies hasbeen an open question since the era of the Einstein satellite. Variousauthors have claimed the discovery of X-ray luminous star-forminggalaxies but in many cases more careful spectroscopic studies of theseobjects have shown that many of them are in fact obscured AGN. In orderto investigate the possibility that such a class of galaxies do exist,we have carried out a cross-correlation between optical and IRAS samplesof galaxies which are known to contain large numbers of star-forminggalaxies and catalogues of sources detected in X-ray surveys. Theselection criteria for the optical follow-up observations was based ontheir X-ray and infrared (IRAS) colours and their X-ray luminosities. Wenote that this sample is by no means complete or uniformly selected andhence cannot be used for statistical studies; nevertheless, confirmationof the existence of such a class of objects would be an important stepand would require us to understand the physical process responsible forsuch powerful X-ray emission. We have initiated an optical spectroscopicsurvey in order to obtain accurate spectroscopic classifications for allthe objects which are claimed to be starburst galaxies. Here we presentpreliminary results from this survey. We have discovered a number ofstarburst galaxies with X-ray luminosities above ~ 10^41 erg s^-1 (forH_0=50 km s^-1 Mpc^-1). We investigate possible origins for the X-rayemission in individual cases.
| 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.
| Neutral hydrogen observations of galaxies in superclusters
Neutral hydrogen observations of spiral galaxies in the Uppsala GeneralCatalog were made with the 91 m telescope in Green Bank. Results of theH I observations are presented for 309 objects north of declination +38deg in the right ascension range between 10 h and 22 h and for a sampleof 46 objects just south of the equator in the region around R.A.between 0 h and 3 h. Many of these objects are outlying members ofsuperclusters and may be useful in the study of deviations from Hubbleflow on supercluster scales. Velocity widths as measured by fivedifferent algorithms are presented along with a profile quality index.
| Forbidden O III emission in two magnitude-limited field-galaxy surveys
The paper presents emission-line strengths for 394 galaxies from thefield-galaxy redshift surveys of Kirshner, Oemler, and Schechter (1978)and Kirshner et al. (1983) as part of a study of the nature of field andvoid galaxies. These data are 95 percent complete in their coverage ofthe forbidden O III 5007, 4959 A emission lines. It is found that 8.8 +or - 1.5 percent of a J magnitude-limited data set have forbidden O III5007 A emission equivalent widths greater than 10 A. There is noevidence that the spatial distribution of emission-line galaxies in eachfield differs from that of galaxies without emission. However, there isa significant increase in the fraction of galaxies with strong forbiddenO III emission in the southern fields of the Kirshner, Oemler, andSchechter (1978) survey as compared with the other survey fields. Theresults are consistent with the conclusion that the fraction of galaxieswith emission is larger in the Bootes void than in the general field,but tighter constraints on the void normal galaxy population are neededto improve the statistics.
| A study of field galaxies. I - Redshifts and photometry of a complete sample of galaxies
As a first step towards a redetermination of the luminosity function andspace distribution of field galaxies, data are presented on amagnitude-limited sample of galaxies in eight fields in the north andsouth galactic polar caps. Redshifts, accurate to about 100 km/s havebeen obtained for 164 of 184 galaxies brighter than J=15.0 (Bapproximately equal to 15.5). Magnitudes and colors have also beenmeasured for a large sample of 807 galaxies, complete to J approximatelyequal to 15.7.
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