Extended Gaseous Disk in the S0 galaxy NGC 4143
  We present our results of the spectroscopic study of the lenticular galaxy
NGC 4143 - an outskirt member of the Ursa Major cluster. Using the observations
at the 6-m SAO RAS telescope with the SCORPIO-2 spectrograph and also the
archive data of panoramic spectroscopy with the SAURON IFU at the WHT, we have
detected an extended inclined gaseous disk which is traced up to a distance of
about 3.5 kpc from the center, with a spin approximately opposite to the spin
of the stellar disk. The galaxy images in the H-alpha and [NII]6583 emission
lines obtained at the 2.5-m CMO SAI MSU telescope with the MaNGaL instrument
have shown that the emission lines are excited by a shock wave. A spiral
structure that is absent in the stellar disk of the galaxy is clearly seen in
the brightness distribution of ionized-gas lines (H-alpha and [NII] from the
MaNGaL data and [OIII] from the SAURON data). A complex analysis of both the
Lick index distribution along the radius and of the integrated colors,
including the ultraviolet measurements with the GALEX space telescope and the
near-infrared measurements with the WISE space telescope, has shown that there
has been no star formation in the galaxy, perhaps, for the last 10 Gyr. Thus,
the recent external-gas accretion detected in NGC 4143 from its kinematics, was
not accompanied by star formation, probably, due to an inclined direction of
the gas inflow onto the disk.
