Contingut
Imatges
Carregar la teva Imatge
DSS Images Other Images
Articles Relacionats
An Einstein Observatory SAO-based catalog of B-type stars
About 4000 X-ray images obtained with the Einstein Observatory are usedto measure the 0.16-4.0 keV emission from 1545 B-type SAO stars fallingin the about 10 percent of the sky surveyed with the IPC. Seventy-fourdetected X-ray sources with B-type stars are identified, and it isestimated that no more than 15 can be misidentified. Upper limits to theX-ray emission of the remaining stars are presented. In addition tosummarizing the X-ray measurements and giving other relevant opticaldata, the present extensive catalog discusses the reduction process andanalyzes selection effects associated with both SAO catalog completenessand IPC target selection procedures. It is concluded that X-rayemission, at the level of Lx not less than 10 exp 30 ergs/s, is quitecommon in B stars of early spectral types (B0-B3), regardless ofluminosity class, but that emission, at the same level, becomes lesscommon, or nonexistent, in later B-type stars.
| Search for Short Time Scale Light Variation in HD 183339 and HD 184927
Not Available
| Radial velocity measurements. II - Ground-based observations of the program stars for the HIPPARCOS satellite
New radial velocities for 446 stars of magnitude 9.0 or brighter in 1616-sq-deg fields of the Northern Hemisphere are determined by automaticPDS measurement of 80-A/mm-dispersion spectra obtained at theObservatoire de Haute Provence using a 17-cm-diameter objective prism.The fields were selected to provide data for the input catalog of theESA Hipparcos astrometric satellite. The measurement techniques andprecision are discussed, and the results are presented in extensivetables and graphs.
| Visual multiples. VIII - 1000 MK types
A total of 1000 new classifications are given for stars brighter than B= 8.0 mag in the Aitken double star catalog. The classificationssupplement 865 classifications obtained in 1981 and 1984. Among thenewly discovered stars are 12 new Ap stars, eight Lambda Bootis stars,one Ba II star, and 60 Am stars. A detailed list of the newclassifications is given.
| 66th Name-List of Variable Stars
Not Available
| Search for light variability among eight stars with anomalous helium content
A search for periodic light variability was carried out among eightstars with anomalous helium content. No variability was detected duringthe observation period for HD 178993, HD 207538, and HD 209339. Theperiod obtained for HD 184927 by Bond and Levato (1977) was confirmed.For HD 191980, HD 208266, and HD 217833, photometric variability wasdetected and periods were obtained.
| Stellar Spectra in Milky way Regions. II. a Region in Cygnus.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1950ApJ...112...90M&db_key=AST
|
Enviar un nou article
Enllaços Relacionats
- - No s'ha trobat enllaços -
Enviar un nou enllaç
Membre dels grups següents:
|
Dades d'Observació i Astrometria
| Constel·lació: | Cygnus |
| Ascensió Recta: | 19h36m52.19s |
| Declinació: | +30°19'30.1" |
| Magnitud Aparent: | 7.639 |
| Distancia: | 341.297 parsecs |
| Moviment propi RA: | 0.9 |
| Moviment propi Dec: | -3.1 |
| B-T magnitude: | 7.547 |
| V-T magnitude: | 7.632 |
Catàlegs i designacions:
|
INHABITED SKY
