SIMBAD references

The results of H_α and [NII]λ6583 observations of the spiral galaxy NGC 1084 at the SAO 6m telescope with a Fabry-Perot interferometer are presented. The complex structure of the emission line profile has revealed the presence of giant star formation regions (``spur'') in the NE part of the galaxy. In this region the H_α line shows two distinct components, with line-of-sight velocity differences of ±(100-150)km/s. The first component corresponds to normal circular rotation. The second velocity component may be a signature of non-circular motions of the ionized gas in shock wave fronts. An increase of the [NII]/H_α line ratio confirms the shock wave interpretation of these features. The ionized gas kinematics in this galaxy is discussed.