Context. Luminous Galactic OH/IR stars have been identified as massive (>4-5 M⊙) asymptotic giant branch (AGB) stars experiencing hot bottom burning and Li production. Their Rb abundances and [Rb/Zr] ratios, as derived from classical hydrostatic model atmospheres, are significantly higher than predictions from AGB nucleosynthesis models, posing a

The Magellanic Clouds (MCs) offer a unique opportunity to study the stellar evolution and nucleosynthesis of massive Asymptotic Giant Branch (AGB) stars in low metallicity environments where distances are known. Rubidium is a key element to distinguish between high mass AGB stars and low mass AGB stars or other types of astronomical objects such as

RXTE PCA Bulge scans detected activity of what appeared to be a known source. However, based on the results presented below, and the report of a new INTEGRAL source IGR J17511-305 (Baldovin et al. ATEL #2196), the activity detected by RXTE is due to a new 245 Hz X-ray pulsar. The source was initially detected on 2009-09-11 at 17:50 UT as a rising

The chemical content of the planetary nebula NGC 3918 is investigated through deep, high-resolution (R ˜ 40 000) UVES (Ultraviolet-Visual Echelle Spectrograph) at VLT (Very Large Telescope) spectrophotometric data. We identify and measure more than 750 emission lines, making ours one of the deepest spectra ever taken for a planetary nebula. Among

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IAUC 5341 available at Central Bureau for Astronomical Telegrams.