#  a70 version 16.06.24  by mph
See changelog at bottom

DISCLAIMER: 
As the ALFALFA catalog is completed (in 2016) its dataset is revised, most notably to account for overlapping
grids but also wherever we are able to make improvements. This dataset therefore supercedes the 40% data
release but itself will be superceded by datasets posted after this date (11 Nov 2015).

Please address questions/comments/suggestions to Martha Haynes (haynes _At& astro.cornell.edu).

    Column entries are:

    Col  1     AGCnr      I6       Entry number in the AGC ("Arecibo General Catalog"), our internal database
    Col  2     Name       A8       A common name from the NGC/IC/CGCG or other catalog (abbreviated to 8 characters)
    Col  3     HIra       F11.6    Right ascension (J2000) of the centroid of the ALFALFA HI signal, in degrees
    Col  4     HIdec      F11.6    Declination (J2000) of the centroid of the ALFALFA HI signal, in degrees
    Col  5     OCra       F11.6    Right ascension (J2000) of the assigned optical counterpart, in degrees, where applicable
    Col  6     OCdeg      F11.6    Declination (J2000) of the assigned optical counterpart, in degrees, where applicable
    Col  7     v21        I5       Heliocentric velocity of the HI line emission, in km/s
    Col  8     w50        I3       Width of the HI line measured at 50% of the peak flux, in km/s
    Col  9     werr       I3       Error on w50, in km/s
    Col 10     flux       F6.2     HI line flux density, in Jy-km/s
    Col 11     fluxerr    F4.2     Error on flux, in Jy-km/s
    Col 12     snratio    F5.1     Signal-to-noise ratio of HI signal
    Col 13     rms        F5.2     RMS noise at 10 km/s, in mJy
    Col 14     dist       F6.1     Distance in Mpc as assigned
    Col 15     loghimass  F5.2     Logarithm of the HI mass in solar units
    Col 16     detcode    I1       Code for HI line detection status
                                   Code 1 = High signal to noise ratio, extragalactic source
                                   Code 2 = Lower signal to noise ratio HI signal coincident with optical counterpart
                                            of unknown redshift
                                   Code 9 = High signal to noise ratio source with no optical counterpart and
                                            likely Galactic high velocity cloud

Notes:  
    -- The AGC number refers both to the location of optical counterpart (where applicable) and the properties of 
       the HI emission.
    -- The resolution of the ALFA receiver is 3.3 x 3.8 arcmin. The HI centroid position is accurate only to about
       18" in the median, and depends on the signal-to-noise ratio and the source extent (particularly relevant
       for the high velocity clouds and the largest galaxies).
    -- Distances are assigned using a combination of primary distance indicators, assignments to known groups and
       clusters, a local flow model or the CMB reference frame.
 
The columns are labelled accordingly in the first line of the CSV file
AGCNr,Name,HIra,HIdec,OCra,OCdec,v21,w50,werr,flux,fluxerr,snratio,rms,dist,loghimass,detcode


CHANGE LOG
16.06.24    Found incorrect AGC assignment:  123324 should be 124324    fixed; mh
            Found incorrect AGC assignment:  123594 should be 124954    fixed; mh