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We present integral field spectroscopy of NGC 5033, a low luminosity Seyfert galaxy. The observations were made with INTEGRAL, a fiber based system operating at the WHT. The intensity map of the Hβemission line represents a spiral or ring-like pattern of HII regions. On the contrary, the [OIII] intensity map morphology is markedly anisotropic. The strong morphological differences imply that the [OIII] emitters represent highly ionized gas illuminated by the central source. The [OIII] map morphology is compatible with a biconical structure of ionization induced by strong extinction in the galaxy disc that also obscures half of the spheroidal stellar bulge. We identify the spectrum corresponding to the Seyfert 1 nucleus from the presence of Hβbroad emission lines. This spectrum is located in a region where strong extinction is expected but exhibits the bluest spectral energy distribution. The Seyfert 1 nucleus seems to be offcenter with respect to the stellar rotation center. This result has been also found in other Seyfert galaxies and interpreted in terms of a past merger. The offcentering could indicate the presence of nonsymmetric departures in the gravitational potential which could be fueling the active nucleus. The kinematics of the [OIII] emitters show important deviations at a kpc scale with respect to the stellar velocity field and show features related to the asymmetrical morphology of the high ionization region.

Integral field spectroscopy in the central $16''\times 12''$(2.4 kpc $\times$1.8 kpc, if H0= 75 km s-1Mpc-1) of the Seyfert 1.9 galaxy NGC 2992has been obtained using the fibre system INTEGRAL. The data are mainly used to study the stellar and ionized gas kinematics. In spite of the photometric disruptions in the outer parts ($r > $6 kpc) produced by the interaction with its close companion (NGC 2993), the present stellar velocity field shows regular rotation. The ionized gas presents several kinematically distinct components. Apart from the outflowing component already reported by other authors, we found an additional (high ionization) kinematic component which seems to be associated with the boundaries of the figure-of-eight-shaped emission detected in the 6 cm radio map. We locate the hidden nucleus in the apex of the biconical structure defined by the [O iii] emission, coincident with the outflow origin and with the center of the dust lane. We do not find any clear evidence of direct influence of the interaction in the kinematics of the stars or the ionized gas in the circumnuclear region of NGC 2992.

The basic concepts for determining the effect of differential atmospheric refraction on integral-field (two-dimensional) spectroscopic observations are presented, and a method for correcting the spectra from this effect is given. The method is demonstrated with real data.

We have developed a new technique to decouple the spectra of the host and the nucleus of type I AGNs using integral field spectroscopy (IFS) data. The technique is a simple extension of methods widely tested in 2D imaging. We present here the results from applying the technique to data taken with INTEGRAL at the 4.2 m WHT telescope on the Seyfert 1 radio-galaxy 3C 120. We obtained, for the first time, a clean spectra of the host galaxy, without contamination from the nuclear source. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We summarize the main conclusions derived from integral field spectroscopy, with optical fibres, of six Seyfert galaxies. More than 95 spectra around the active nucleus have been obtained showing asymmetric emission-line profiles at different positions. Continuum and emission-line intensity maps and ionized gas velocity fields have been derived for these six galaxies. We also present the stellar velocity field for NGC 1068, NGC 3516 and NGC 985.

We present bidimensional spectroscopy of the central region (94 × 122) of the Seyfert galaxy NGC 3516 in the two spectral ranges 4186-5839 Å and 6110-7890 Å. The data (95 × 2 spectra) were simultaneously obtained with an optical fibre system (2D-FIS). The two-dimensional velocity map of the stellar component was obtained from the Mg Ibabsorption lines. The kinematic axes of this stellar velocity field agree very well with the geometrical axes determined from the outer isophotes. In consequence, despite the existence of an outer ring and a bar, the stars in the circumnuclear region rotate regularly. New accurate value for the systemic velocity (2593 ± 15 km s-1), the orientation of the line of nodes (53° ± 5°), and the amplitude of the velocity field (~80 km s-1) are presented. The center of rotation has also been determined and could be spatially displaced with respect to the active nucleus. We have performed an emission-line profile decomposition and identified several components. In addition to the component responsible for the Z-shaped morphology of the line-emission region, gaseous systems showing large widths (FWHM ~ 10-20 Å) and extreme blueshift (-900 km s-1) have been found. The comparison between the stellar and ionized-gas velocity maps favors the precessing twin-jet model over the bent-outflow hypothesis to explain the Z-shaped morphology and two-dimensional kinematics of the line-emission region.