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The 3s(2)3p(2 3)P(1.2)-3s3p(3) S-5(2) intercombination lines for Si-like Rh have been investigated using the techniques of beam-foil spectroscopy. Two lines have been identified as belonging to these transitions having, however, different wavelengths from what would be expected based on published iso-electronic trends. The identifications suggested here are strengthened by requirements on (a) the

We consider the origin of the so-called S stars orbiting the supermassive black hole at the very center of the Galaxy. These are usually assumed to be massive main-sequence stars. We argue instead that they are the remnants of low-to-intermediate mass red giants that have been scattered into near-radial orbits and tidally stripped as they approach the central black hole. Such stars retain only low

We report on experimental branching fractions (BFs) for 19 transitions from the three 3d 5( 6S)4s4p( 3P) y6P levels in Fe II, measured in Fourier transform spectra of a Penning discharge lamp and a hollow cathode lamp. The transition wavelengths span the interval between 1600 and 2850 Å. Absolute oscillator strengths ( f-values) have been derived by combining the BFs with experimental radiative li

The conceptual design of the Large Earth-based Solar Telescope (LEST)has evolved through the years. In 1995-97 it was discussed whether atechnology demonstration telescope could be built at a lower cost thanthe LEST originally proposed. In 1997, a de-scoped LEST design, theso-called "Mini-LEST", was conceived and proposed to the LEST community.The telescope has an innovative design with a small fi

We prove the existence of the old and metal-rich moving group HR 1614. This is done using the new Hipparcos parallaxes in combination with metallicities derived from Strömgren photometry, supported by dynamical simulations of the evolution of old moving groups in the galactic potential. A new selection criterion for this moving group is presented as well as a new, extended sample of probable membe

We present new results on a study of the weak s-process elemental abundances in the M supergiant alpha Ori (M2Iab). We have conducted the abundance analysis through comparison of synthetic with observed spectra in the two infrared spectral regions 0.7 - 1.1 mu m and 2.1 - 2.3 mu m, where the molecular and atomic line densities are less than in the optical region and where many of the relevant elem

We present an analytical algorithm for deriving the shapes of the deformable mirrors to be used for multiconjugate adaptive correction on a large telescope. The algorithm is optimal in the limit where the overlap of the wave-front contributions from relevant atmospheric layers probed by the guide stars is close to the size of the pupil. The fundamental principle for correction is based on a minimi

We report on the observation of the bright, long gamma-ray burst, GRB 090926A, by the Gamma-ray Burst Monitor and Large Area Telescope (LAT) instruments on board the Fermi Gamma-ray Space Telescope. GRB 090926A shares several features with other bright LAT bursts. In particular, it clearly shows a short spike in the light curve that is present in all detectors that see the burst, and this in turn