# Strong non-circular motions of gas in the spiral galaxy NGC 1084

Authors
Publication Date
Sep 01, 1999
Source
INSPIRE-HEP
Keywords
The results of $H_\alpha$ and [NII]$\lambda 6583$ 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 $H_\alpha$ line shows two distinct components, with line-of-sight velocity differences of $\pm(100-150)\km$. 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 ${[NII]}/H_\alpha$ line ratio confirms the shock wave interpretation of these features. The ionized gas kinematics in this galaxy is discussed.