We report the discovery of WASP-4b, a large transiting gas-giant planet with an orbital period of 1.34 days. This is the first planet to be discovered by the SuperWASP-South observatory and CORALIE collaboration and the first planet orbiting a star brighter than 16 th magnitude to be discovered in the Southern hemisphere. A simultaneous fit to high-quality lightcurves and precision radial-velocity measurements leads to a planetary mass of 1.22 +0.09 −0.08 M Jup and a planetary radius of 1.42 +0.07 −0.04 R Jup . The host star is USNO-B1.0 0479-0948995, a G7V star of visual magnitude 12.5. As a result of the short orbital period, the predicted surface temperature of the planet is 1761 K, making it an ideal candidate for detections of the secondary eclipse at infrared wavelengths.

Aims. We present two-dimensional spectroscopy of the extremely metal-deficient blue compact dwarf (BCD) galaxy SBS 0335-052E to study physical conditions, element abundances and kinematical properties of the ionised gas in this galaxy. Methods. Observations were obtained in the spectral range λ3620-9400 Å with the imaging spectrograph GIRAFFE on the UT2 of the Very Large Telescope (VLT). These observations are the first ones carried out so far with GIRAFFE in the ARGUS mode which allows one to simultaneously obtain 308 spectra covering a 11. 4×7. 3 region. 3726,3729 Å, coincides with the youngest south-eastern star clusters 1 and 2, the emission of He II 4686 Å line is offset to the more evolved north-west clusters 4, 5. This suggests that hard ionising radiation responsible for the He II λ4686 Å emission is not related to the most massive youngest stars, but rather is related to fast radiative shocks. This conclusion is supported by the kinematical properties of the ionised gas from the different emission lines as the velocity dispersion in the He II λ4686 Å line is systematically higher, by ∼50-100%, than that in other lines. The variations of the emission line profiles suggest the presence of an ionised gas outflow in the direction perpendicular to the galaxy disk. We find a relatively high electron number density N e of several hundred cm −3 in the brightest part of SBS 0335-052E. There is a small gradient of the electron temperature T e and oxygen abundance from the East to the West with systematically higher T e and lower 12+log O/H in the western part of the galaxy. The oxygen abundances for the whole H II region and its brightest part are 12 + log O/H = 7.29 ± 0.02 and 7.31 ± 0.01, respectively. We derive the He mass fraction taking into account all systematic effects. The He mass fraction Y = 0.2463 ± 0.0030, derived from the emission of the whole H II region, is consistent with the primordial value predicted by the standard Big Bang nucleosynthesis model. We confirm the presence of Wolf-Rayet stars in cluster 3.

Abstract. The F5 subgiant Procyon A (α CMi, HR 2943) was observed with the C fiber-fed echelle spectrograph on the 1.2-m Swiss telescope at La Silla in February 1999. The resulting 908 high-accuracy radial velocities exhibit a mean noise level in the amplitude spectrum of 0.11 m s −1 at high frequency. These measurements show significant excess in the power spectrum between 0.6-1.6 mHz with 0.60 m s −1 peak amplitude. An average large spacing of 55.5 µHz has been determined and twenty-three individual frequencies have been identified.

Abstract. We present a wide multi-wavelength database of most observations of the quasar 3C 273 obtained during the last 30 years. This database is the most complete set of observations available for an active galactic nucleus (AGN). It contains nearly 20 000 observations grouped together into 70 light curves covering 16 orders of magnitude in frequency from the radio to the γ-ray domain.The database is constituted of many previously unpublished observations and of most publicly available data gathered in the literature and on the World Wide Web (WWW). It is complete to the best of our knowledge, except in the optical (UBV ) domain where we chose not to add all observations from the literature. In addition to the photometric data, we present the spectra of 3C 273 obtained by the International Ultraviolet Explorer (IUE) satellite. In the X-ray domain, we used the spectral fit parameters from the literature to construct the light curves.Apart from describing the data, we show the most representative light curves and the average spectrum of 3C 273. The database is available on the WWW in a homogeneous and clear form and we wish to update it regularly by adding new observations.Send offprint requests to: M. Türler (ISDC)

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