Rapid simultaneous observations of Fe II and Balmer emission lines of X OPH

Abstract

Sudden brightening of Fe II and Balmer (Hβ and Hα) lines of X Oph was observed on 28 - 29 May, 1986. Equivalent width of Fe II and Hβ lines increased by a factor of two and that for Hα line by a factor of four, during the brightening phase of the star. This brightening phenomenon has been explained in the framework of "Coronal Radiative Instability".