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Публикации по объекту
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.
| Galaxy coordinates. II. Accurate equatorial coordinates for 17298 galaxies
Using images of the Digitized Sky Survey we measured coodinates for17298 galaxies having poorly defined coordinates. As a control, wemeasured with the same method 1522 galaxies having accurate coordinates.The comparison with our own measurements shows that the accuracy of themethod is about 6 arcsec on each axis (RA and DEC).
| Supernovae discovered in the period of July 1996-June 1997 at the BAO.
Not Available
| Kinematics of the local universe. VII. New 21-cm line measurements of 2112 galaxies
This paper presents 2112 new 21-cm neutral hydrogen line measurementscarried out with the meridian transit Nan\c cay radiotelescope. Amongthese data we give also 213 new radial velocities which complement thoselisted in three previous papers of this series. These new measurements,together with the HI data collected in LEDA, put to 6 700 the number ofgalaxies with 21-cm line width, radial velocity, and apparent diameterin the so-called KLUN sample. Figure 5 and Appendices A and B forcorresponding comments are available in electronic form at thehttp://www.edpsciences.com
| Parameters of 2447 Southern Spiral Galaxies for Use in the Tully-Fisher Relation
I-band luminosities, rotational velocities, and redshifts of 1092 spiralgalaxies have been measured by CCD photometry and Hα spectroscopyusing the 1 m and 2.3 m telescopes at Siding Spring Observatory,respectively. The results are tabulated. Luminosity profiles andHα rotation curves are given for the galaxies. When these resultsare combined with similar data for 1355 spiral galaxies publishedpreviously (Mathewson, Ford, & Buchhorn, hereafter Paper I), itprovides a large, uniform, and unique data set with which to measure,via the Tully-Fisher relation, the peculiar velocities of galaxies inthe local universe to a distance of 11,000 km s^-1^ (Mathewson &Ford). Taking advantage of the opportunity for publishing this data inmachine-readable form, in the CD-ROM, we have also included similar datafor the 1355 galaxies in Paper I.
| Kinematics and dynamics of the MKW/AWM poor clusters
We report 472 new redshifts for 416 galaxies in the regions of the 23poor clusters of galaxies originally identified by Morgan, Kayser, andWhite (MKW), and Albert, White, and Morgan (AWM). Eighteen of the poorclusters now have 10 or more available redshifts within 1.5/h Mpc of thecentral galaxy; 11 clusters have at least 20 available redshifts. Basedon the 21 clusters for which we have sufficient velocity information,the median velocity scale is 336 km/s, a factor of 2 smaller than foundfor rich clusters. Several of the poor clusters exhibit complex velocitydistributions due to the presence of nearby clumps of galaxies. We checkon the velocity of the dominant galaxy in each poor cluster relative tothe remaining cluster members. Significantly high relative velocities ofthe dominant galaxy are found in only 4 of 21 poor clusters, 3 of whichwe suspect are due to contamination of the parent velocity distribution.Several statistical tests indicate that the D/cD galaxies are at thekinematic centers of the parent poor cluster velocity distributions.Mass-to-light ratios for 13 of the 15 poor clusters for which we havethe required data are in the range 50 less than or = M/LB(0)less than or = 200 solar mass/solar luminosity. The complex nature ofthe regions surrounding many of the poor clusters suggests that thesegroupings may represent an early epoch of cluster formation. Forexample, the poor clusters MKW7 and MKWS are shown to be gravitationallybound and likely to merge to form a richer cluster within the nextseveral Gyrs. Eight of the nine other poor clusters for which simpletwo-body dynamical models can be carried out are consistent with beingbound to other clumps in their vicinity. Additional complex systems withmore than two gravitationally bound clumps are observed among the poorclusters.
| The nature of unidentified far-infrared point sources
Sources discovered by the Infrared Astronomical Satellite with spectrathat rise steeply from 60 to 100 microns are a mixed sample of externalgalaxies, condensations in the interstellar medium, and potentiallyunknown astronomical objects. Sources in regions of low total H I columndensity (as determined with the all-sky 21-cm line surveys), and with nonearby cataloged external galaxy, were observed for presence of 20-cmcontinuum emission (with the NRAO VLA), enhanced 21-cm H I line emission(with the NAIC Arecibo 305 m), and molecular line emission (with theNRAO 12 m, HCRO 6 m, and FCRAO 14 m). Based on the CO detection rate, 70percent of our sample are small interstellar molecular clouds. Theremainder are mostly faint external galaxies. The dust column densitiesof the interstellar condensations were determined from the IR flux,using a spherical-cloud model for the radiative transfer of theinterstellar radiation field (ISRF). The CO column densities weredetermined using the large-velocity-gradient model for the excitationand radiative transfer of the rotational transitions. About half of theinterstellar sources have normal dust-to-gas ratios and ISRF heating.Sources with excess infrared emission, compared to the molecular columndensity, are protostellar candidates.
| IC 2006 - an elliptical galaxy with a polar ring
IC 2006 is surrounded by a ring in which the direction of gas motion isopposite to the rotation of the galaxy's stellar body. This peculiaritycan be explained easily if it is assumed that the ring lies in the polarplane. The parameters of the ring are determined, and it is found thatthe ring has an elliptical shape.
| H I observations of galaxies in the Hercules supercluster. II - Additional UGC galaxies and galaxies in selected CGCG fields
The second installment of a H I redshift survey in the region of theHercules supercluster is presented. This part of the survey presents 218H I spectra of galaxies selected from the UGC which extends thepreviously begun survey of UGC galaxies in that region. In addition,spectra of 136 galaxies from selected CGCG fields are given. The CGCGfields were chosen to cover the projected position of the Hercules void.Measured H I parameters from the spectra are given. This survey wasconducted for application of the Tully-Fisher relation to search forstreaming motion around the void in front of the supercluster. Theselection effects affecting such a search are discussed in detail.
| 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.
| 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.
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