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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.
| The 74th Special Name-list of Variable Stars
We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.
| 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.
| Mesures de vitesses radiales. VII. Accompagnement AU sol DU programme d'observation DU satellite Hipparcos. Radial velocities. VII. Ground based measurements for Hipparcos.
We publish 734 radial velocities of stars distributed in 28 fields of4x4deg. We continue the PPO series (Fehrenbach et al. 1987; Duflot etal. 1990 and 1992), using the Fehrenbach objective prism method.
| 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.
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