A b s tra c t. -Optical emission line velocities in NGC 1365 are presented along 35 slit positions, of which 18 have not been published earlier. Diagrams of emission line velocities as function of distance along the slits are presented, and separate velocity fields are derived for the disc as given by the low excitation lines, combined with H i 21 cm VLA data, and for the nuclear outflow cone as given mainly by the high excitation lines. An algorithm for creating a velocity field and contour maps based on measurements along randomly oriented spectrograph slits is given in the Appendix. Detailed discussions and interpretations of these velocity fields are given elsewhere. The combined optical and 21 cm disc velocity field is available by an anonymous ftp.

Abstract. The Cloverleaf quasar, H1413+117, has been photometrically monitored at ESO (La Silla, Chile) and with the NOT (La Palma, Spain) during the period [1987][1988][1989][1990][1991][1992][1993][1994]. All good quality CCD frames have been successfully analysed using two independent methods (i.e. an automatic image decomposition technique and an interactive CLEAN algorithm). The photometric results from the two methods are found to be very similar, and they show that the four lensed QSO images vary significantly in brightness (by up to 0.45 mag), nearly in parallel. The lightcurve of the D component presents some slight departures from the general trend which are very likely caused by micro-lensing effects. Upper limits, at the 99% confidence level, of 150 days on the absolute value for the time delays between the Send offprint requests to: rolf.stabell@astro.uio.no Based on observations collected at the European Southern Observatory (La Silla, Chile) and with the Nordic Optical Telescope (La Palma, Spain). photometric lightcurves of this quadruply imaged variable QSO, are derived. This is unfortunately too large to constrain the lens model but there is little doubt that a better sampling of the lightcurves should allow to accurately derive these time delays. Pending a direct detection of the lensing galaxy (position and redshift), this system thus constitutes another good candidate for a direct and independent determination of the Hubble parameter.

Nuclear regions of galaxies generally host a mixture of components with different excitation, composition, and kinematics. Derivation of emission line ratios and kinematics could then be misleading, if due correction is not made for the limited spatial and spectral resolutions of the observations. The aim of this paper is to demonstrate, with application to a long slit spectrum of the Seyfert 2 galaxy NGC 1358, how line intensities and velocities, together with modelling and knowledge of the point spread function, may be used to resolve the differing structures. In the situation outlined above, the observed kinematics differs for different spectral lines. From the observed intensity and velocity distributions of a number of spectral lines, and with some reasonable assumptions about structure of different subcomponents to diminish the number of free parameters, the true line ratios and velocity structures may be deduced. A preliminary solution for the nuclear structure of NGC 1358 is obtained, involving a nuclear point source and an emerging outflow of high excitation, ending with shock and postshock cloud as revealed by the velocities, as well as a nuclear emission line disk rotating in the potential of a stellar bulge and expressing a radial excitation gradient. The method results in a likely scenario for the nuclear structure of the Seyfert 2 galaxy NGC 1358. For definitive results an extrapolation of the method to two dimensions combined with the use of integral field spectroscopy will be necessary.

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