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CHARM2: An updated Catalog of High Angular Resolution Measurements
We present an update of the Catalog of High Angular ResolutionMeasurements (CHARM, Richichi & Percheron \cite{CHARM}, A&A,386, 492), which includes results available until July 2004. CHARM2 is acompilation of direct measurements by high angular resolution methods,as well as indirect estimates of stellar diameters. Its main goal is toprovide a reference list of sources which can be used for calibrationand verification observations with long-baseline optical and near-IRinterferometers. Single and binary stars are included, as are complexobjects from circumstellar shells to extragalactic sources. The presentupdate provides an increase of almost a factor of two over the previousedition. Additionally, it includes several corrections and improvements,as well as a cross-check with the valuable public release observationsof the ESO Very Large Telescope Interferometer (VLTI). A total of 8231entries for 3238 unique sources are now present in CHARM2. Thisrepresents an increase of a factor of 3.4 and 2.0, respectively, overthe contents of the previous version of CHARM.The catalog is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/431/773
| Infrared and visual lunar occultations measurements of stellar diameters and new binary stars detections at the Calar Alto 1.5 m telescope
We present a program of routine lunar occultations, at optical andnear-IR wavelengths, recently started at the 1.5 m Spanish telescope atthe Calar Alto Observatory. Both a CCD and an infrared array detectorare used. The program is aimed mainly at the detection and investigationof binary systems, although results in other areas of stellar researchare also anticipated. Occultations are reported for a total of 40 stars.Among these, SAO 164567, SAO 78258and AG+24 788 have been discovered to be binaries,with projected separations as small as 0.006 arcsec. Furthermore,binarity is suspected in the case of SAO 78119 andSAO 79251. Additionally, the angular diameter of thelate-type giant 30 Psc and of the infrared starV349 Gem have been accurately measured, the latterfor the first time. We finally evaluate the instrumentation performancein terms of the limiting magnitude and angular resolution, and discussapplications to larger telescopes.Appendix A is only available in electronic form athttp://www.edpsciences.org
| Metal-abundance determinations from near-UV spectra - Application to the mean metal abundance of M32
Near-UV spectra for the nucleus of the elliptical galaxy M32 and for 60field stars have been obtained which cover the wavelength interval3200-3900 A at a resolution of 2.5 A FWHM. A depression in thepseudocontinuum shortward of 3504 A is found to be quite sensitive tometal abundance. The results indicate that the luminosity-weighted meanmetal Fe/H abundance ratio for M32 at 3500 A is about -0.1, and that thegiant branch contributes slightly less than 30 percent of the light at4000 A. The luminosity-weighted N/Fe abundance ratio is shown to beapproximately equal to that of solar neighborhood stars.
| Red horizontal-branch stars in the galactic disk
A quantitative, three-dimensional spectral classification systemdeveloped by Rose (1984), which uses 2.5-A resolution spectra in theblue, has been used to identify a class of red horizontal branch (RHB)stars in the Galactic disk that are similar to those in the 'metal rich'globular cluster M 71. The RHB are denoted as evolved stars by their SrII 4077 line, and are distinguished from post-main sequence starsevolving through the same region of the HR diagram on the basis of theunique appearance of their CN 3883 and 4216 A bands. The RHB starsconsitute at least 5 percent of the entire giant branch population ofthe disk.
| Objective-prism discoveries in the northern sky. I
Attention is given to 175 northern hemisphere stars whose newlyrecognized peculiar, or otherwise prepossessing characteristics havebeen noted in a preliminary inspection of moderate dispersion objectiveprism plates. The plates were obtained with a 10-deg prism. The starlist gives HD or BD, alpha and delta values, magnitude, and type.
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