We present accurate B, V, R photometry of the Sculptor dwarf spheroidal galaxy. The data have been collected with the Wide Field Imager available at 2.2 m ESO/MPI telescope and cover an area of about 100×40 arcmin2 around the Sculptor center. The final catalogue includes 100,000 stars. We found that blue and red Horizontal Branch stars present

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Microquasars are in many ways similar to their massive counterparts, the radio loud population of AGNs. One aspect that is just beginning to receive the due amount of attention is their interaction with the interstellar medium. This interaction is similar on a qualitative level, but different quantitatively: The interstellar medium provides a much

We present our first results for a sample of southern high-amplitude delta Scuti stars (HADS), based on a spectrophotometric survey started in 2003. For CY Aqr and AD CMi, we found very stable light and radial velocity (RV) curves; we confirmed the double-mode nature of ZZ Mic, BQ Ind and RY Lep. Finally, we detected gamma -velocity changes in RS

The global parameters of the Pleiades cluster are derived from the comparison of observed and computed frequencies of six multi-periodic delta Scuti stars. The best frequency fits lead to a distance modulus of 5.70 in good agreement with the pre-Hipparcos MS fitting methods.

We present abundance measurements, based on high resolution optical spectroscopic data obtained with the UVES at VLT, for 10 stars in the blue horizontal branch (BHB) of the Galactic globular cluster NGC 1904 (M79). In agreement with previous findings for other clusters, we obtain normal abundances for stars cooler than Te. ~ 11000 K, and largely