On the Interaction in a Quartet of Galaxies
  We performed the Fabry-Perot scanning interferometry of the quartet of
galaxies NGC 7769, 7770, 7771 and 7771A in Ha line and studied their velocity
fields. We found that the rotation curve of NGC 7769 is weakly distorted. The
rotation curve of NGC 7771 is strongly distorted with the tidal arms caused by
direct flyby of NGC 7769 and flyby of a smaller neighbor NGC 7770. The rotation
curve of NGC 7770 is significantly skewed because of the interaction with much
massive NGC 7771. The rotation curves and morphological disturbances suggest
that the NGC 7769 and NGC 7771 have passed the first pericenter stage, however,
probably the second encounter has not happened yet.
