A& A Supplement series, Vol. 121, January 1997, 1 - 9
Received November 7; accepted April 9, 1996
O.K. Sil'chenko - A.V. Zasov - A.N. Burenkov - J. Boulesteix
Send offprint request: O.K. Sil'chenko
Sternberg Astronomical Institute, University av. 13,
Moscow 119899, Russia
Special Astrophysical Observatory, Nizhnij Arkhyz, Karachaj-Cherkess
Republic, 357147 Russia
Observatoire de Marseille, 2 Place Le Verrier,
F-13248 Marseille Cedex 04, France
The Sc galaxy NGC 6181 was observed at the 6m telescope of SAO RAS with the scanning Perot-Fabry interferometer in the H emission line and at the 1m telescope of SAO RAS in BVRI broadband filters with CCD. Subtraction of the mean circular rotation curve from the two-dimensional velocity field has revealed a ring-like zone with a diameter about of 2 kpc where strong radial gas motions are present. The form of the ring is almost perfectly circular in the plane of the galaxy. It is located closer to the center than the beginning of the well-defined spiral structure, but outside of the central bulge-dominated region. The detected radial velocity reduced to the plane of the galaxy is about and probably is azimuthally dependent. The very inner region of the galaxy, or 0.5 kpc, shows a turn of the dynamical major axis by about . Central continuum isophotes are also twisted which suggests the presence of small nuclear bar.
keywords: galaxies: spirals, kinematics -- scanning Perot-Fabry interferometry