Contenidos
Imágenes
Subir su imagen
DSS Images Other Images
Artículos relacionados
Einstein Observatory magnitude-limited X-ray survey of late-type giant and supergiant stars Results are presented of an extensive X-ray survey of 380 giant andsupergiant stars of spectral types from F to M, carried out with theEinstein Observatory. It was found that the observed F giants orsubgiants (slightly evolved stars with a mass M less than about 2 solarmasses) are X-ray emitters at the same level of main-sequence stars ofsimilar spectral type. The G giants show a range of emissions more than3 orders of magnitude wide; some single G giants exist with X-rayluminosities comparable to RS CVn systems, while some nearby large Ggiants have upper limits on the X-ray emission below typical solarvalues. The K giants have an observed X-ray emission level significantlylower than F and F giants. None of the 29 M giants were detected, exceptfor one spectroscopic binary.
| Radial velocities of southern stars obtained with the photoelectric scanner CORAVEL. III - 790 late-type bright stars Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...59...15A&db_key=AST
| The sun among the stars. V - A second search for solar spectral analogs: The Hyades' distance A five-part search for a match of the solar spectrum throughout the sky,down to the limit of the Bright Star Catalog, is completed by 20A-resolution comparisons of G-type star photoelectric violet spectrawith those of Jupiter satellites and the blue sky. It is confirmed thatsolar analogs are rare. The strengths, relative to the sun, of theabsorption features at 3850 and 3740 A are measured quantitatively forall 164 stars observed. Their dependence on B-V and U-V leads to thesame solar colors previously derived from the solar analogs alone, withB-V equals 0.66 and U-B equals 0.20. Giants and subgiants are excludedfrom consideration, and stellar metal content dependence was closelyobserved. The sun is found to fit the mass-luminosity relation of theHyades within 0.16 m, independent of the assumed helium abundance, ifevolutionary and metal abundance effects are taken into account.
|
Enviar un nuevo artículo
Enlaces relacionados
- - No se han encontrado enlaces -
En viar un nuevo enlace
Miembro de los siguientes grupos:
|
Datos observacionales y astrométricos
Constelación: | Centauro |
Ascensión Recta: | 13h36m50.50s |
Declinación: | -34°28'04.0" |
Magnitud Aparente: | 6.5 |
Distancia: | 159.236 parsecs |
Movimiento Propio en Ascensión Recta: | -6.6 |
Movimiento Propio en Declinación: | -37 |
B-T magnitude: | 7.773 |
V-T magnitude: | 6.589 |
Catálogos y designaciones:
|