Data Set Overview
  =================
  The Asteroid Polarimetric Database (APD) is compiled by D.F.
  Lupishko and S.V. Vasiliev of Karazin Kharkiv National University,
  Ukraine.  This database tabulates the original data comprising
  degree of polarization as a function of phase angle of the asteroid,
  and additional parameters where available.  The data included are
  published asteroid polarimetry for which observation dates are
  available, and unpublished asteroid polarimetry data which are
  provided to Lupishko along with the dates of observation.  The last
  column of the APD file is a reference code consisting of the
  publication year and name of the first author.  The full citations
  for the papers may be found in the accompanying reference list file.
  For unpublished data, the code Unpubl. along with the name of the
  observer is used.  This version of the APD is current through
  January 22, 2008.
 
  Modification History
  ====================
  This data set was first reviewed and ingested in 1996, and was
  updated in 1997 with additional polarimetric data published since
  then, as well as an added table of derived polarimetric parameters
  including polarization curves and polarimetric albedos of selected
  asteroids.  In 1999, 2000, and 2006 the data set was updated again
  with
  additional polarimetric observations published since the previous
  version.  This version created in 2008 represents the addition of
  additional results from the literature and  from individual
  researchers.
 
  Parameters
  ==========
  The parameters tabulated in 'apd.tab' are filter, phase angle,
  degree of polarization, polarization position angle, position angle
  of the scattering plane, and both degree of polarization and
  position angle in the proper coordinate system measured from the
  perpendicular to the scattering plane.
 
  Ancillary Data
  ==============
  Parameters of the polarimetric curve for individual asteroids, as
  well as polarimetric albedos, are compiled in the file
  'apdcurv.tab'.  This file reproduces the data in Table 2 of Lupishko
  and Mohamed (1996) [LUPISHKO&MOHAMED1996], and has not been updated
  since that time.
 
  The entries in 'apd.tab' include a reference to the published paper
  in which the data appeared, and to the observatory and telescope
  where the observations were made.  The full references of the papers
  cited mat be found in the file 'apdrefs.tab' in the data directory.
  A general compilation of asteroid polarimetry papers is also
  included in the file 'polrefs.txt' in the document directory.  The
  telescopes and observatories are listed in the document
  'polobs.txt'.
 
  References
  ==========
 
  Lupishko, D.F., and R.A. Mohamed, A New Calibration of the
  Polarimetric Albedo Scale of Asteroids, Icarus 119, 209-213, 1996.

Confidence Level Overview
  =========================
  This is a compilation of asteroid polarimetry results from the
  published literature.  The user is referred to the individual
  publications for information on the confidence level of any given
  observation.
 
  The table of polarimetric parameters and polarimetric albedos,
  'apdcurv.tab', provides no error values, but instead gives a quality
  code as an assessment of the quality of the data.