Context. Found within the central molecular zone, the Quintuplet is one of the most massive young clusters in the Galaxy. As a consequence it offers the prospect of constraining stellar formation and evolution in extreme environments. However, current observations suggest that it comprises a remarkably diverse stellar population that is difficult

A high resolution spectrum (Δλ = 0.2 Å) of the Population II star HD 76932 from the archive of the IUE satellite has been analysed in a search for measurable resonance absorption lines due to 9Be. Matching the observations by a synthesized model of the wavelength region around the doublet at 3130 Å gives a conservative upper limit for the abundance

We are performing a survey of a sample of 17 radio jets with Chandra and HST, with the aim of finding their X-ray and optical counterparts. In this paper, we present the preliminary Chandra results for the first six sources observed and analyzed so far. In four of them an X-ray jet is clearly detected. We compare the X-ray morphologies to the radio

We observed the neutron star X-ray transient 2S 1803-245 in quiescence with the X-ray satellite XMM-Newton, but did not detect it. An analysis of the X-ray bursts observed during the 1998 outburst of 2S 1803-245 gives an upper limit to the distance of

Aims: We present the abundance analysis of 12 planetary nebulae ionized by [WC]-type stars and weak-emission-line stars (wels) obtained from high-resolution spectrophotometric data. Our main aims are to determine the chemical composition of the nebulae and to study the behaviour of the abundance discrepancy problem (ADF) in this type of planetary

This project sought to consider two important aspects of the planetary nebula NGC 3242 using new long-slit HST/STIS spectra. First, we investigated whether this object is chemically homogeneous by spatially dividing the slit into different regions and calculating the abundances of each region. The major result is that the elements of He, C, O, and