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We present the third installment of HI sources extracted from the Arecibo Legacy Fast ALFA extragalactic survey. This dataset continues the work of the Virgo ALFALFA catalog. The catalogs and spectra published here consist of data obtained during the 2005 and 2006 observing sessions of the survey. The catalog consists of 578 HI detections within the range 11h 36m < R.A.(J2000) < 13h 52m and +08 deg < Dec.(J2000) < +12 deg, and cz_sun < 18000 km/s. The catalog entries are identified with optical counterparts where possible through the examination of digitized optical images. The catalog detections can be classified into three categories: (a) detections of high reliability with S/N > 6.5; (b) high velocity clouds in the Milky Way or its periphery; and (c) signals of lower S/N which coincide spatially with an optical object and known redshift. 75% of the sources are newly published HI detections. Of particular note is a complex of HI clouds projected between M87 and M49 that do not coincide with any optical counterparts. Candidate objects without optical counterparts are few. The median redshift for this sample is 6500 km/s and the cz distribution exhibits the local large scale structure consisting of Virgo and the background void and the A1367-Coma supercluster regime at cz_sun ~7000 km/s. Position corrections for telescope pointing errors are applied to the dataset by comparing ALFALFA continuum centroid with those cataloged in the NRAO VLA Sky Survey. The uncorrected positional accuracy averages 27 arcsec ~(21 arcsec ~median) for all sources with S/N > 6.5 and is of order ~21 arcsec ~(16 arcsec ~median) for signals with S/N > 12. Uncertainties in distances toward the Virgo cluster can affect the calculated HI mass distribution.
We present the first installment of HI sources extracted from the Arecibo Legacy Fast ALFA (ALFALFA) extragalactic survey, initiated in 2005. Sources have been extracted from 3-D spectral data cubes and then examined interactively to yield global HI
We present the catalog of ~31500 extragalactic HI line sources detected by the completed ALFALFA survey out to z < 0.06 including both high signal-to-noise ratio (> 6.5) detections and ones of lower quality which coincide in both position and recessi
We present a second catalog of HI sources detected in the Arecibo Legacy Fast ALFA Survey. We report 488 detections over 135 square degrees, within the region of the sky having 22h<RA<03h and +26deg<Dec<+28deg. We present here the detections that hav
We report the results of an HI blind survey of 80deg^2 of the Virgo cluster, based on the 08deg < delta < 16 deg strip of ALFALFA, the Arecibo Legacy Fast ALFA Survey. 187 HI sources of high significance are found providing a complete census of HI so
We present a current catalog of 21 cm HI line sources extracted from the Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) survey over ~2800 square degrees of sky: the alpha.40 catalog. Covering 40% of the final survey area, the alpha.40 catalo