On the Nature of the Apparent Ring Galaxy SDSS J075234.33+292049.8
  (abridged) An object classified as a galaxy in on-line data bases and
revealed on sky survey images as a distant ring galaxy is a rare case of polar
ring galaxy where the ring is only slightly inclined to the equatorial plane of
the central body. SDSS imaging indicates that the diameter of the ring is about
36 kpc. The SDSS data was combined with long-slit spectroscopic observations
and with Fabry-Perot Interferometer H-beta mapping obtained at the Russian
Academy of Sciences 6-m telescope. We derived the complex morphologies of this
presumed ring galaxy from a combination of SDSS images and from the kinematical
behaviour of the central body and of the ring, and determined the stellar
population compositions of the two components from SDSS colours, spectroscopy,
and evolutionary stellar synthesis models. The ring metallicity is slightly
under-abundant. The total luminosity and the total mass of the system are not
extreme, but the rather high M/L~20 indicates the presence of large amounts of
dark matter. Two alternative explanations of this object are proposed (1) a
ring formed by two semi-circular and tight spiral arms at the end of a central
bar with a warp or precession of the ring material. The object could,
therefore, be explained as an extreme SBa(R) galaxy, or (2) a Polar Ring Galaxy
where the inner object is an S0 and the ring is significantly more luminous
than the central object. The compound object would then be similar to the NGC
4650A galaxy, being a rare object with a polar component only modestly inclined
to the equatorial plane of the central body. Arguments for (and against) both
explanations are given and discussed, with the second alternative being more
acceptable.
