Title | A comprehensive study of the peculiar spiral galaxy NGC 1808. II. VLA HI line observations. |
Authors | Koribalski, B.; Dahlem, M.; Mebold, U.; Brinks, E. |
Bibcode | 1993A&A...268...14K Search ADS ↗ |
Abstract | Here we report results of H I line observations of the starburst galaxy NGC 1808 with the Very Large Array (VLA) in its CnD hybrid configuration. The analysis of the global HI distribution and the velocity field revealed new details in the kinematics of this peculiar galaxy. We find 1) the clear signature of a warp in the outer gas layer, and 2) outflow of neutral hydrogen gas from the nuclear region. The Warp has been deduced from the near-circular shape of the HI gas distribution ({angular size} ~ 10' > optical size) which is in contrast to the ellipticity of the disk. Through a `tilted-ring model' fit we derive a warp angle of about i_w_ = 23^deg^. In the northeastern part of the disk, where prominent dust filaments seem to emerge from the nuclear region, we find a velocity anomaly which indicates outflow of HI gas into the halo of the galaxy. This means that we determined the flow direction of the dust filaments which have long been known from optical observations. Finally we discuss the possibility that the warp and the outflow of gas have been caused by interactions with the neighbour galaxy NGC 1792. |
Objects | 6 Objects Search NED ↙ |