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International audience; We report the results of a kinematical H alpha survey of the Large Magellanic Cloud (LMC) presented in the form of a kinematical and photometric catalogue of 210 H ii regions. The observations have been obtained with a scanning Fabry-Perot interferometer that produced data cubes corresponding to 66 different pointings over this galaxy, each with a field of view of 38 arcmin, covering almost the whole extent of the LMC. We find a bimodal distribution of the H alpha luminosity of LMC H ii regions. We also derive the local star formation and star formation rate (SFR) per unit area of the nebulae, concluding that star formation in the LMC has proceeded until the present time at an average rate of roughly 0.11 M-aS (TM) yr(-1). Also, we do not find any correlation between the SFR or I (SFR) pound with Delta V (full width at half-maximum for a single Gaussian profile and the difference in velocities for multiple-components velocity profiles), the diameter, the distance to the kinematical centre of the LMC and age of the nebulae. Over most of the LMC Delta V appears to be of the order of 30 km s(-1). However, in a few regions the Delta V of the velocity profiles is as large as 50-100 kms(-1), corresponding to identified supernova remnants and superbubbles undergoing expansion motions.

We present the detailed velocity field of the central 2 kpc of the LINER galaxy NGC 1672. The iso- velocity map shows a rotational pattern with a velocity gradient of 50 km s-ˡ arcsec-ˡ in the inner 6" (1"≈ 70 pc), indicating a mass of ≈ 9x 108 Mʘ inside a radius of 125 pc, equivalent to a density of ≈ 2 x 1011 Mʘ kpc-³. It also shows some asymmetries on a larger scale. An o†set of ≈ 60 pc between the nuclear continuum barycenter and the kinematical center is also found. Satoh"s model Ðtting to the observed velocity Ðeld reveals several nonaxisymmetric residuals, which do not correlate well with the bar or the circumnuclear ring of H II regions. The inner rotation curve of NGC 1672 reveals that the circumnuclear ring of star formation is located on an inner Lindblad resonance (ILR), and not near the peak of the Lindblad curve, Ω − (k/2), as suggested by previous works, which also claimed that the ring rotates faster than its ambient. This motion is not conÐrmed by the two-dimensional residual- velocity map.

The results of an optical monitoring campaign on the active nucleus in the luminous Seyfert 1 galaxy Fairall 9 are presented. This campaign was undertaken in parallel with ultraviolet spectroscopic moni- toring with the IUE satellite which is described in a separate paper. The primary purpose of this program is to measure the response times (or "" lags II) of the emission lines to continuum variations and thus to extend the range in luminosity of active galactic nuclei (AGNs) for which such measurements have been made. The main conclusions of this work are as follows: 1. Continuum (at 5340 variations of amplitude D12% are detected on timescales as short as D20 Ae ) days. These variations are much larger than the typical uncertainties in the measurements, which are of order D2%. Over D94 days, a factor of 2 change in the nuclear continuum was observed. 2. The optical continuum light curve resembles that of the UV continuum, showing two "" events II of low-amplitude variations with a duration of D70 days and with no measurable lag between the UV and optical continuum light curves. The UV data show a third larger amplitude event that occurred after the optical monitoring had terminated and unfortunately went unobserved in the optical. 3. The Hb emission-line Nux also underwent signi-cant, low-amplitude ("20%) variations. Cross- correlation analysis reveals that Hb lags behind the UV continuum by about 23 days, a value much smaller than what was previously suggested by earlier variability studies. However, this small lag is con- sistent with the lags for the UV lines during this campaign in the sense that the Hb lag is approximately 50% larger than that of Ly aj 1216, as it has been found for lower luminosity AGNs. 4. The Hb di†erence pro-le produced by subtracting the low-state from the high-state data can be described as a two-component structure with blue and red components of similar width (D2500 km s~1) and that appear to vary in phase. Subject headings: galaxies: active E galaxies: individual (Fairall 9) E galaxies: nuclei E galaxies: Seyfert

The Galactic plane has been observed between l = 337 and l = 342 in the frame of an H Survey of the Southern Milky Way. This area is known to be rich in radio sources but poor in H emission. The analysis of high resolution proles of the H emission observed in this direction nevertheless enabled to distinguish 6 dierent velocity components: 2 faint layers of diuse ionized hydrogen at 0 and 12 km s 1 (VLSR), 2 brighter layers at 28 and 39 km s 1 including individual HII regions, a faint patch at 50 km s 1 and two isolated bright HII regions at 61 km s 1 . Combining these H observations with stellar and radio data we conclude about the most probable distances for the dierent components.

The LMC is being surveyed in the Hα emission line with a scanning Fabry-Perot interferometer, attached to the 36 cm telescope of the Observatoire de Marseille. The present results concern the kinematical mapping of bright nebulae; it shows that the kinetic energy involved in the gas motion is closely related to the evolutionary stage of the embedded stars. In particular, in the 30 Dor nebula, a few one-peaked line profiles remain at the boundaries of the shells, among the numerous split areas. The 50-100 pc shells exhibit a relatively usual spherical expansion, with velocities in the same range at the boundaries. On the contrary, the 10-20 pc shells of the central core show different velocities of the one-peak sides of the shells.

The new observational facility available at Bosque Alegre Station (Cordoba Observatory, ARGENTINA) is described. The spectrograph is mounted on the 1.54m Nasmyth reflector. The detector is a CCD camera (Photometrics AT 200), equipped with a 1024×1024 chip (Thomson CH 7896). The deviations from linearity of response are below 0.1%, the readout noise is 4 electrons pixel-1 and the dark noise is about 6 electrons pixel-1 hour-1. The quantum efficiency of the camera has a 45% peak in 650nm and is enhanced in the blue by a Metachrome II coating. The spectrograph consists of a Maksutov-type collimator system of 600mm focal length (f/12) and an apochromatic camera lens of 200mm focal length (f/3.5). The pixel size projected onto the sky is 0.38“, which corresponds to an equivalent focal length of 10.38m. Three gratings are available for the spectroscopic modes: 300 g/mm, 600 g/mm and 1,200 g/mm. This spectrograph is of a modular design, intended to allow different configurations and observing modes during the same night. The configurations available, either imaging or spectroscopic, are: direct image, with the possibility of using coloured or interference filters, field of view: 5.7 x 5.7 arcmin multi-pupil image with lens array (by using field-pupil inversion), with or without filters long-slit grating spectroscopy, slit length: 4 arcmin on the sky integral field spectroscopy, with grating and lens array (Tiger type, Courtes 1980) two-dimensional, scanning Fabry-Perot spectrometry (high spectral resolution) (Cigale type, Boulesteix et al. 1984) cross-dispersion (Fabry-Perot + grating) spectrometry (high spectral resolution) (Pytheas type, le Coarer 1992) Echelle spectroscopy (high spectral resolution).

We report the results of a kinematic Hα survey of the Large Magellanic Cloud (LMC) in the form of a kinematic and photometric catalogue of 210 HII regions, the radial velocity field of the ionized hydrogen in this galaxy, and the LMC Rotation Curve obtained from the velocity field. These data aim at understanding the LMC HII regions, bubbles and superbubbles in a global (galactic) scale so that we could have a 3D view and separate the rotation due to gravitational potential from other motions such as expansions.

In 1990 we began an Hα survey of the Milky Way and the Magellanic clouds at ESO La Silla with a 36 cm telescope. The main goal of this survey is to study in detail complexes of HII regions, as well as the global spiral structure of our Galaxy.