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Time series analysis of V 368 Cephei photometry
Our time series analysis of {{V 368 Cep}} photometry ascertains therotation period of 2.74d uniquely. The manifestations of starspotinduced luminosity variations in this chromospherically active starinclude rapid light curve changes and differential rotation of about 3%.We conclude that the single rapidly rotating variable {{V 368 Cep}} is ahigh inclination K1{v} post T Tauri star. Table~5 is only available inelectronic form at CDS via anonymous ftp to edarc.u-strasbg.fr(130.79.1285) or via http://cdsweb.u-strasbg.fr/Abstract.html
| Photospheric activity of HD 220140, the optical counterpart of the X-ray source H 2311+77
We present and discuss the photoelectric observations of HD 220140obtained at Merate Observatory and compare them with the ones obtainedby Bianchi et al. (1991). The star shows a variable light activity witha fundamental period of 2.766 d. At the epoch of our observations thelight curve was double-wave shaped, while at the epoch of the Bianchi etal. (1991) data it was essentially a single wave. The light curvevariability as well as the changing mean brightness of the star observedin our data can be explained by the rotation of a star with at least twogroups of photospheric dark spots, whose extent and/or location ischanging with characteristic time-scales of a few rotational cycles.
| The nature of HD220140 from optical and IUE observations
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Osservazione e dati astrometrici
| Costellazione: | Cefeo |
| Ascensione retta: | 23h14m18.90s |
| Declinazione: | +77°56'58.0" |
| Magnitudine apparente: | 8.263 |
| Distanza: | 109.769 parsec |
| Moto proprio RA: | 16.5 |
| Moto proprio Dec: | -1 |
| B-T magnitude: | 9.04 |
| V-T magnitude: | 8.328 |
Cataloghi e designazioni:
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