Tartalom
Képek
Kép feltöltése
DSS Images Other Images
Kapcsolódó cikkek
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.
| Radial-velocity measurements. III - Ground observations accompanying the HIPPARCOS satellite observation program: Measurements of the radial velocities of 391 stars in 12 fields
The radial velocities of 391 stars, obtained with the Fehrenbachobjective prism associated to the Schmidt telescope of the Observatoirede Haute-Provence are presented. These stars belong to fields speciallychosen for containing several Hipparcos input catalog star members. Eachfield is presented independently. The list includes HD and BDidentifiers when available, 1950 coordinates, spectral type, and B and Vmagnitudes as they appear in the CSI catalog, the radial velocity, theprobable error, the number of independent measurements and commentariessuch as known radial velocity and their origin.
| Optical identification of the millisecond pulsar 1937 + 214
A 20th magnitude red object, undetectable on the Palomar Sky Surveyprints, is proposed as an optical identification candidate for themillisecond pulsar. The image containing the object was obtained fromthree CCD exposures, one of 300 s and two of 600 s, which were filteredto remove cosmic ray events, offset into coincidence, and digitallystacked together to increase the signal-to-noise ratio. The part of theresulting image containing the object is shown, and several stars in thefield are listed. The procedure for locating the optical candidate isdescribed; the candidate is about one sigma error box from the radioposition.
|
Új cikk hozzáadása
Kapcsolódó hivatkozások
- - (nincs kapcsolódó hivatkozás) -
Új link hozzáadása
Besorolás csoportokba:
|
Pozíciós és asztrometriai adatok
| Csillagkép: | Kis Róka |
| Rektaszcenzió: | 19h39m58.70s |
| Deklináció: | +21°34'04.9" |
| Vizuális fényesség: | 8.311 |
| Távolság: | 211.416 parszek |
| RA sajátmozgás: | 2 |
| Dec sajátmozgás: | -10.6 |
| B-T magnitude: | 8.5 |
| V-T magnitude: | 8.327 |
Katalógusok és elnevezések:
|
