Ýçindekiler
Görüntüler
Resim Yükleyin
DSS Images Other Images
Ýlgili Makaleler
Contribution to the search for binaries among Am stars - VI. Orbital elements of ten new spectroscopic binaries, implications on tidal effects
We present the results of a radial-velocity study of 10 Am stars (HD19342, 19910, 36360, 102925, 126031, 127263, 138406, 155714, 195692 and199360) observed at Observatoire de Haute-Provence with the CORAVELinstrument. We find that these systems are spectroscopic binaries whoseorbital elements are determined for the first time. Both components weremeasured for HD 126031, an eclipsing binary, whereas the other systemswere detected as single-line binaries only. Physical parameters wereinferred from this study for the primaries of all systems, and for thesecondary of HD 126031. We observed a higher incidence ofsynchronized/circularized systems than predicted by the theoreticalmodels of the radiative dissipation of dynamical tides.
| The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.
| Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
| Miscellaneous spectroscopic notes
Results of slit-spectrograph observations are reported for approximately260 stars. The data presented range from recognition of many new Ap, Am,and other unusual stars to H-alpha observations of early-typesupergiants and Be stars. The material discussed was obtained over thepast 40 years at a number of U.S. observatories and at the DominionAstrophysical Observatory in Victoria, B.C.
| The frequency of Ap-stars with long rotation periods
Light variability was observed over time intervals of months to years inthe stars HD 55540, HD 71066, HD 94660, and HD 187474. The significanceof these results is discussed in terms of the frequency of chemicallypeculiar CP2 stars showing (light) variability with periods longer thanone month. This frequency, relative to the whole CP2 population, mustlie somewhere between 4 and 16 percent. Observations, properlydistributed in time, of a small subgroup of CP2 stars will be sufficientto obtain an accurate ratio of the number of LP-CP2 stars to the totalnumber of CP2 stars. These observations, when continued until theperiodicity is detected, could contribute also to the discussion whetherthese long periods should be identified with the rotation period.
|
Yeni bir Makale Öner
Ýlgili Baðlantýlar
Yeni Bir Baðlantý Öner
sonraki gruplarýn üyesi:
|
Gözlemler ve gökölçümü verileri
| Takýmyýldýz: | Ejderha |
| Sað Açýklýk: | 15h28m39.26s |
| Yükselim: | +61°43'36.0" |
| Görünürdeki Parlaklýk: | 6.895 |
| Uzaklýk: | 281.69 parsek |
| özdevim Sað Açýklýk: | -0.9 |
| özdevim Yükselim: | 7.2 |
| B-T magnitude: | 7.045 |
| V-T magnitude: | 6.908 |
Kataloglar ve belirtme:
|
INHABITED SKY
