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|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).
|The Updated Zwicky Catalog (UZC)|
The Zwicky Catalog of galaxies (ZC), with m_Zw<=15.5, has been thebasis for the Center for Astrophysics (CfA) redshift surveys. To date,analyses of the ZC and redshift surveys based on it have relied onheterogeneous sets of galaxy coordinates and redshifts. Here we correctsome of the inadequacies of previous catalogs by providing (1)coordinates with <~2" errors for all of the 19,369 catalog galaxies,(2) homogeneously estimated redshifts for the majority (98%) of the datataken at the CfA (14,632 spectra), and (3) an estimate of the remaining``blunder'' rate for both the CfA redshifts and for those compiled fromthe literature. For the reanalyzed CfA data we include a calibrated,uniformly determined error and an indication of the presence of emissionlines in each spectrum. We provide redshifts for 7257 galaxies in theCfA2 redshift survey not previously published; for another 5625 CfAredshifts we list the remeasured or uniformly rereduced value. Among ournew measurements, 1807 are members of UZC ``multiplets'' associated withthe original Zwicky catalog position in the coordinate range where thecatalog is 98% complete. These multiplets provide new candidates forexamination of tidal interactions among galaxies. All of the newredshifts correspond to UZC galaxies with properties recorded in the CfAredshift compilation known as ZCAT. About 1000 of our new measurementswere motivated either by inadequate signal-to-noise in the originalspectrum or by an ambiguous identification of the galaxy associated witha ZCAT redshift. The redshift catalog we include here is ~96% completeto m_Zw<=15.5 and ~98% complete (12,925 galaxies out of a total of13,150) for the right ascension ranges 20^h>=alpha_1950<=4^h and8^h>=alpha_1950<=17^h and declination range-2.5d<=delta_1950<=50^deg. This more complete region includes allof the CfA2 survey as analyzed to date. The Great Wall structurepersists throughout the northern survey region. Dedicated to the memoryof Jim Peters, whose friendship, skill, and dedication were essential tothis work.
|The CFA Redshift Survey: Data for the South Galactic CAP|
We present redshifts for a sample of 4391 galaxies with magnitudem_B(0)<=15.5 covering 20^h<=alpha<=4^h in right ascension and-2.5d<=delta<=90^deg in declination. This sample is complete forall galaxies in the merge of the Zwicky et al. and Nilson catalogs inthe south Galactic cap. Redshifts for 2964 of these were measured aspart of the second CfA Redshift Survey. The data reveal large voids inthe foreground and background of the Perseus-Pisces Supercluster. Thelargest of these voids lies at a mean velocity ~8000 km s^-1, hasdiameter ~5000 km s^-1, and is enclosed by a complex of densestructures. The large structure known as the Perseus-Pisces Superclusterforms the near side of this complex. On the far side of this large void,at a mean velocity ~12,000 km s^-1, there is another coherent densewall. The structures in this survey support the view that galaxiesgenerally lie on surfaces surrounding or nearly surrounding low-densityregions or voids.
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