תוכן
תמונות
הוסף תמונה שלך
DSS Images Other Images
מאמרים קשורים
A Photometric and Spectroscopic Study of 3 Vulpeculae: An Observer's Nightmare
We describe photometry of 3 Vulpeculae obtained with the Four CollegeAutomated Photoelectric Telescope and spectroscopy obtained with the1.22 m telescope of the Dominion Astrophysical Observatory. We haveanalyzed differential uvby photometric observations obtained over 7 yr.Three main frequencies (f1=0.9719, f2=0.7923, andf3=0.8553 cycles day-1) were found, as well as asum frequency (f1+f2=1.76420 cyclesday-1). A study of the photographic region usinghigh-dispersion spectrograms obtained with a Reticon detector at thecoudé spectrograph confirms the variable nature of 3 Vul as a 53Persei star and indicates that the star's abundances are normal formain-sequence band B stars. The new spectra were combined with thosepreviously published to confirm an orbital period very close to 1 yr.Finally, comparison with models yielded both a mass (4.16Msolar) and an age (25 Myr), and a mass range for thecompanion (0.6-1.1 Msolar). With an orbital period of almost1 yr and a pulsation period of almost 1 day, this star is indeed anobserver's nightmare.
| 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.
| A New B Variable, HD182865
The suspected 53 Persei type variable 3 Vulpeculae has been on theobserving program of the Four College Consortium Automatic PhotoelectricTelescope (FCCAPT) for three years. When reducing the data it wasnoticed that the standard deviation of the check (HD182865) andcomparison (HD181164) star measures was significantly higher thanexpected on the basis of results from other observing programs. Aperiodogram analysis of these observations revealed a strong peak at0.156 c/d (6.43 days). In order to determine which of the two stars wasvarying separate periodogram analyses were performe on the variableminus comparison and the variable minus check data. Since the period ofthe variable is significantly shorter than 6 days it was hoped that oneof these two periodograms would have the 6.43 day period present whilethe other one would not. Indeed, this proved to be the case. We identifythe previously undetected variable as the check star HD182865. Theperiod is rather long to be a pulsational one for a B8 star. A search ofthe SIMBAD data base revealed no other information on this star otherthan the HD spectral type. The amplitude of variation is greatest in theStromgren u filter and least in the Stromgren y filter. This, togetherwith the B8 HD spectral type, and its rather long period lead us tosuspect that the variation is a rotational phenomenon with the period ofvariation equal to its rotational period. This would suggest that it islikely a chemically peculiar star. This work has been supported in partby NSF grants AST86-16362, AST91-15114, and USE-9156184 to the Collegeof Charleston.
| 3 Vulpeculae - A nonradial pulsator in a one-year binary system
3 Vul is found to be a single-lined spectroscopic binary with a periodof 367 days, very nearly equal to one year. Velocity observations overtwo decades, in combination with archival data, have producedsufficiently good phase coverage to yield a well-defined orbit.Nonetheless, residuals from a Keplerian velocity curve are large thanexpected for the sharp-lined B6 III primary: Night-to-night and possiblymore rapid non-Keplerian radial-velocity variations occur.High-resolution observations of Si II lines reveal marked line-profilechanges during single and successive nights. Preliminary evidencesuggests that low-amplitude photometric variations may be present also.It is suggested that the primary is a member of the nonradiallypulsating '53 Persei' class of variable stars.
| Catalog of O-B stars observed with Tokyo Meridian Circle
A catalog of the O-B stars, selected from 'Blaauw-Parenago' list andRubin's catalog, has been compiled on the FK4 system by the observationsmade with Gautier 8-inch Meridian Circle at the Tokyo AstronomicalObservatory during the period, 1971 to 1979. It contains 1059 stars andwas compiled for the future establishment of high precision propermotions of O-B stars.
| H-beta photometry of northern intermediate galactic latitude early-type stars and galactic structure away from the plane
Photoelectric H-beta photometry is presented for 255 early-type stars atintermediate galactic latitudes. Absolute magnitudes and distances arederived for the more luminous stars. Those with visual magnitudes lessthan or equal to 2.5 and at distances of up to 1 kpc from the galacticplane may follow the spiral structure in the plane.
| On the origin of intermediate-latitude OB stars
An attempt is made to trace the origin of early-type stars observed atappreciable distances from the galactic plane. Because uncertainties inthe proper motions make space motions and hence dynamical lifetimesrather inaccurate, a theory of oscillations normal to the plane has beenused to compute radial velocities for 138 intermediate-latitude OBstars. These theoretical values are then compared with the observedradial velocities, and it is found that the low-velocity stars wereprobably ejected from the plane some time after formation, while thehigh-velocity stars were ejected very soon after formation. Velocitiesof ejection perpendicular to the plane are computed and show a narrowdistribution with a mean absolute value of 7 km/s together with a spreadof velocities from about 40 to over 200 km/s. The data are in reasonableagreement with a 'sling' effect and 'runaway' origin for the stars inthe sample.
| UBV photometry and MK spectral classification of northern early-type stars at intermediate galactic latitudes
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977MNRAS.180..691H&db_key=AST
| Photoelectric distances of 461 Northern OB-stars and galactic structure from Hγ- luminosities Author: Beer, A.
Abstract image available at:http://adsabs.harvard.edu/abs/1964MNRAS.128..261B
|
הכנס מאמר חדש
לינקים קשורים
הכנס לינק חדש
משמש של הקבוצה הבאה
|
תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | נבל |
| התרוממות ימנית: | 19h18m28.19s |
| סירוב: | +26°03'25.6" |
| גודל גלוי: | 7.536 |
| מרחק: | 1000 פארסק |
| תנועה נכונה: | 0.1 |
| תנועה נכונה: | -2.9 |
| B-T magnitude: | 7.484 |
| V-T magnitude: | 7.532 |
קטלוגים וכינוים:
|
