Discovery of metal line emission from the Red star in IP Peg during outburst maximum

Observations of the eclipsing dwarf nova IP Peg during outburst reveal metal lines in emission, such as Mg II 4481 A. Analysis using Doppler tomography locates emission of helium and metal lines on the inner Roche lobe of the secondary star. Such multi-line Roche-lobe imaging presents a new tool in mapping the red star’s ionization structure.