Contents
Images
Upload your image
DSS Images Other Images
Related articles
Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| A search for previously unrecognized metal-poor subdwarfs in the Hipparcos astrometric catalogue
We have identified 317 stars included in the Hipparcos astrometriccatalogue that have parallaxes measured to a precision of better than 15per cent, and the location of which in the(MV,(B-V)T) diagram implies a metallicitycomparable to or less than that of the intermediate-abundance globularcluster M5. We have undertaken an extensive literature search to locateStrömgren, Johnson/Cousins and Walraven photometry for over 120stars. In addition, we present new UBV(RI)C photometry of 201of these candidate halo stars, together with similar data for a further14 known metal-poor subdwarfs. These observations provide the firstextensive data set of RCIC photometry ofmetal-poor, main-sequence stars with well-determined trigonometricparallaxes. Finally, we have obtained intermediate-resolution opticalspectroscopy of 175 stars. 47 stars still lack sufficient supplementaryobservations for population classification; however, we are able toestimate abundances for 270 stars, or over 80 per cent of the sample.The overwhelming majority have near-solar abundance, with theirinclusion in the present sample stemming from errors in the colourslisted in the Hipparcos catalogue. Only 44 stars show consistentevidence of abundances below [Fe/H]=-1.0. Nine are additions to thesmall sample of metal-poor subdwarfs with accurate photometry. Weconsider briefly the implication of these results for clustermain-sequence fitting.
| Radial velocities in selected B-G stars
Spectroscopic observations of a sample of nearby B-G stars are reported.The observations were obtained at resolution 19 km/s in the spectralregion near the 448.1228-nm line of Mg II using a CCD-detectorspectrograph on the coude-feed telescope at KPNO on April 16-20, 1986.The data are presented in extensive tables and briefly characterized.
|
Submit a new article
Related links
Submit a new link
Member of following groups:
|
Observation and Astrometry data
| Constellation: | Ophiucus |
| Right ascension: | 16h50m28.88s |
| Declination: | -11°18'55.8" |
| Apparent magnitude: | 9.51 |
| Proper motion RA: | 57.2 |
| Proper motion Dec: | -23 |
| B-T magnitude: | 10.179 |
| V-T magnitude: | 9.566 |
Catalogs and designations:
|
