Radial velocities of four LSB galaxies

We present integral-field spectroscopy of the ionized gas in the central regions of four galaxies with a low surface brightness disk taken with the Visible Multi Object Spectrograph at the Very Large Telescope and aimed at testing the accuracy in the determination of the central logarithmic slope alpha of the mass density radial profile rho(r){prop.to}r^alpha^ in this class of objects. For all the sample galaxies we subtracted the best-fit model of gas in circular motions from the observed velocity field and derived the residuals.

Only ESO-LV5340200 is characterized by a regular velocity field. We extracted the velocity curves of this galaxy along several position angles, in order to estimate the uncertainty in deriving the central gradient of the total mass density from long-slit spectroscopy.