1997A&A...319..886S

An analysis of the minima timings covering more than a century showed that two seasons of activity can be established (JD=2410000-2423000 and JD=2435000-2450000), separated by an interval about 12000 days (33 years) long in which the period was almost invariable. Most period variations in each season have character of episodes of abrupt changes of both signs and are separated by intervals of almost constant period. The length of interval separating the episodes is more than a thousand days. The net result of the respective episodes was shortening of the orbital period. The episodes of the period decrease in 1982 and 1987 coincide with the minimum brightness of the loser (photometry of Olson and Etzel 1993AJ....106..342O). It is concluded that variations of the orbital period in RW Tau are not evolutionary and probably are not directly related to the mass transfer events. Instead, an alternative interpretation incorporating changes of the internal structure of the convective loser is offered.