C. Bartolini, A. Bonifazi, A. Guarnieri and A. Piccioni, Istituto di Astronomia, University of Bologna; and A. Giangrande and F. Giovannelli, Istituto di Astrofisica Spaziale, Frascati, telex: "A preliminary inspection of spectra of HDE 245770 = A0535+26 obtained with the Bologna l.5-m telescope at Loiano between Oct. 31 and Dec. 17 reveals unusual activity for this star. H-alpha, H-beta, H-gamma and He I 587.6-nm lines are strongly in emssion. The emission features have weakened in recent days, but Ha and He I remain strong. UBV photoelectric photometry during the same period shows a fading of ~ 0.2 mag with respect to the practically constant luminosity of the last five years. It seems probable that the Be star is experiencing a shell ejection. This hypothesis is also supported by the presence of unusual absorption features, which were particularly strong on Dec. 6."
International Astronomical Union Circular
- Pub Date:
- December 1981