Direct Evidence for Modulated Irradiation of Secondary Components in Dwarf Novae during Superoutbursts

Contribution from the irradiated secondary component is detected in the light curves of five dwarf novae observed during superoutbursts. Their superhump light curves show that irradiation is modulated with the superhump phase. This strengthens the new interpretation of superhumps (Smak 2009) as being due to irradiation controlled mass transfer rate resulting in modulated dissipation of the kinetic energy of the stream.