NGC 7468 a galaxy with an inner polar disk(8)

We present our spectroscopic observations of the galaxy NGC 7468 performed at the 6-m Special Astrophysical Observatory telescope using the UAGS long-slit spectrograph, the multipupil fiber spectrograph MPFS, and the scanning Fabry-Perot interferometer (IF

8Shalyapina et al.:NGC7468:a galaxy with an inner polar disk

the central region of the galaxy,the stars and the ionized gas belong to different subsystems.(

3)The arc-shaped lobes on the northern and southern sides of the galaxy are not kinematically decoupled to an extent that the presence of the polar ring suggested by Whitmore et al.(1990)be confirmed.They are probably either tidal structures or weakly developed spiral arms.

(4)The intensity ratio of the forbidden and permitted lines confirms that the emission in HII regions results from photoionization.The derived metallicity is lower than the solar value(∼0.3Z⊙).

(5)The detected inner disk allows the galaxy NGC7468to be classified as belonging to PRGs.The cen-tral collision with a dwarf galaxy and its capture could be responsible for the formation of the inner polar disk. The velocityfield we derived shows that there is no reason to believe that the arc-shaped lobes on the northern and southern sides of the galaxy,which belong to the putative polar ring(Whitmore et al.1990),are a kinematically de-coupled ring.These are probably either tidal structures or weakly developed spiral arms.

Acknowledgements.We are grateful to the Large Telescopes Program Committee(LTPC)for allocating observational time on the6-m telescope.This study was supported by the Russian Foundation for Basic Research(project nos.02-02-16033and 03-02-06766)and the Russian Ministry of Education(project no.E02-11.0-5).

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