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Spectral Classification of Stars in A Supplement to the Bright Star Catalogue
MK spectral types are given for about 584 stars in A Supplement to theBright Star Catalogue. These are compared with Hipparcos parallaxes tocheck the reliability of those classifications. The estimated errors are+/-1.2 subtypes, and 10% of the luminosity classes may be wrong.
| First radial velocities for 146 bright F- and G-type stars
We have obtained an average of 5.7 radial velocities for 146 northernstars of types F and G (all luminosity classes) listed in 'A Supplementto the Bright Star Catalogue' as having no previously known radialvelocity measures. Those were obtained with charge coupled devices(CCDs) and a cross-correlation technique; the intrinsic velocityaccuracy, based on stars of apparently constant velocity, is probablyless than +/- 0.3 km/s per mean. Of those stars 14% are newly discoveredSB2 stars. The prevelance of rapid profile variations (in minutes orhours) in most of the broad-lined F-type stars makes it difficult toobtain accurate measures for them.
| Interstellar polarization from observations of A and F stars in high and intermediate galactic latitudes, and from stars in the Mathewson and Ford polarization catalogue
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986A&AS...64..487K&db_key=AST
| A magnitude limited stellar X-ray survey and the F star X-ray luminosity function
An X-ray survey has been conducted of stars brighter than visualmagnitude 8.5 that have serendipitously fallen into the fields of viewof the Imaging Proportional Counter of the Einstein Observatory. Thesurvey includes 227 separate 1 x 1 deg fields, containing 274 stars witha visual magnitude of no more than 8.5 and covering a wide range ofspectral types and luminosity classes. X-ray emission was detected from33 stars, and upper limits have been determined for the remainder of thesample. F type stars dominate the detected sample, and most of these areshown to be dwarfs. An X-ray luminosity function for dF stars has beendeduced, and reveals that the average 0.2-4.0 keV luminosity of thesestars is around 10 to the 29th erg/sec. Constraints have been placed onthe high luminosity tails and medians of the X-ray luminosity functionsfor other types of stars.
| UVBY beta photometry of 210 B, A, and F stars in ten areas centered on extragalactic radio sources at high northern galactic latitudes
As part of a study of the reddening properties of the interstellarmedium at the South Galactic pole and particularly along the southernpart of the galactic plane, a catalog of ubvy beta photometry of 210 B,A, and F stars in 10 areas of equal size covering 160 sq deg atlatitudes higher than +30 deg is presented. Each of the observed areasis centered at radio sources that have emission or absorption in the21-cm line; and the main aim of the study is to obtain color excessesfor a comparison of neutral hydrogen column densities, tentativelyassociated with distinct clouds and with the occurrence of dust in theseclouds. V, (b-y), m1, c1, and beta are presented for the 210 stars.
| Estimation of spectral classifications for bright southern stars with interesting Stromgren indices
This paper investigates the degree of success with which uvby photometrycan be applied to predict spectral classifications for 947 A, F, and Gstars brighter than an apparent magnitude of 8.3 and with four-colorindices indicating some kind of interesting, unusual, or peculiarspectrum. One or several possible spectral classifications are estimatedfor each star from photometry alone, double stars are distinguished, andthe estimates are compared with published classifications. The resultsshow that the framework provided by uvby photometry can be extended toinclude most G and K stars, reddened stars, peculiar stars, and certaintypes of double star.
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Datos observacionales y astrométricos
| Constelación: | Serpiente |
| Ascensión Recta: | 15h24m19.84s |
| Declinación: | +08°28'53.6" |
| Magnitud Aparente: | 7.063 |
| Distancia: | 155.521 parsecs |
| Movimiento Propio en Ascensión Recta: | -12.3 |
| Movimiento Propio en Declinación: | -12.2 |
| B-T magnitude: | 7.991 |
| V-T magnitude: | 7.14 |
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