He II $\hat{I}»$4686 emission from the massive binary system in $\hat{I}\cdot$ Car: constraints to the orbital elements and the nature of the periodic minima

M. Teodoro, A. Damineli, B. Heathcote +27

η Carinae is an extremely massive binary system in which rapid spectrum variations occur near periastron. Most notably, near periastron the He II $\hat{I}»4686$ line increases rapidly i…