We present spatially resolved echelle spectroscopy, obtained at high spectral resolution, for 15 multiple-shell planetary nebulae. Most exhibit faint detached halos (IC 1295, MA 3, M 2-2, M 2-40, NGC 6804, NGC 6826, NGC 6884, NGC 6891, NGC 7662, PM 1-295, and Vy 2-3). Furthermore, we have included some with attached shells (IC 1454, K 1-20, K 3-73

In recent years the view of Galactic globular clusters as simple stellar populations has changed dramatically, it is now thought that basically all globular clusters host multiple stellar populations, each with its own chemical abundance pattern and colour-magnitude diagram sequence. Recent spectroscopic observations of asymptotic giant branch

This paper reports on the fifth STEPHI multi-site photometric campaign in 1993 devoted to the δ Scuti star BDS 1269A (VW Ari). The observation yielded a data set of 150.7 hours. Our analysis has resulted in 7 identified frequencies. These frequencies exhibit three couple-frequency character, and also fit the previous investigations quite well. An

While testing a Strömgren spectrophotometer attached to the 1.5 m telescope at the San Pedro Mártir observatory, Mexico, a number of A-type stars were observed, one of which, HD 207331, presented clear indications of photometric variability. CCD photometric data acquired soon after, confirmed its variability. In order to determine its pulsation

P Cygni is one of the most luminous variable stars in our Galaxy. It is the only luminous blue variable which does not show photometric variability on a scale of 1 - 2m. In this paper a possible interpretation of the small-scale photometric variability of ΔV ≍ 0.2m for this peculiar supergiant is discussed.

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