¹ Hvar Observatory, Faculty of Geodesy, Zagreb University, 10000 Zagreb, Croatia
² Astronomical Institute of the Charles University, V Holesovickach 2, CZ-180 00 Praha 8, Czech Republic
³ Astronomical Institute, Academy of Sciences, CZ-251 65 Ondrejov, Czech Republic
⁴ Department of Physics and Astronomy, University of Victoria, P.O. Box 3055 STN CSC, Victoria, B.C., Canada V8W 3P6
⁵ Astronomical Institute of the Slovak Academy of Sciences, SK 059 60 Tatranska Lomnica, Slovak Republic
⁶ Erindale Campus and Department of Astronomy and Astrophysics, University of Toronto, Mississauga, ON, L5L IC6, Canada
⁷ Association des Utilisateurs de Detecteurs Electroniques (AUDE), 28, rue du Pic du Midi, F-31130 Quint-Fonsegrives, France

Photometric and spectroscopic monitoring of the B star HD 6226 resulted in the finding that this object is a new bright Be star with a clear positive correlation between the brightness and emission-line strength. The emission-line episodes are relatively short and seem to repeat frequently which make this star an ideal target for studying the causes of the Be phenomenon. The general character of the light variations, the low v sin i = 70 km s^-1 and the very pronounced line asymmetries of the HeI 6678 line, seen both outside and during emission-line episodes, are all attributes which make HD 6226 phenomenologically similar to the well-known Be star  CMa. Radial velocities of the deepest parts of the metallic and HeI 6678 absorption lines vary with a strict period of 2.61507 d over the whole time interval covered by the observations, and the velocities of the broad outer wings of the same lines varying in anti-phase and with a lower amplitude. This periodicity could not be found in the radial-velocity variations of the sharp core of H. There is some indication of variability on a time scale of 24-29 days but our data are insufficient to prove that conclusively. A comparison of the line spectrum obtained outside emission episodes with synthetic spectra, standard dereddening of UBV magnitudes and Hipparcos parallax all agree with the conclusion that HD 6226 is a star with the following basic properties: T_eff = 17,000 K, log g = 3.0[cgs], mass of 5 M and radius of 11 R. The strong emission-line episodes may appear regularly, in a cycle of 630 days but with different durations of individual cycles. HD 6226 is probably one of the first Be stars for which the Be nature was predicted on the basis of the character of its light and colour changes.

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