Alex Gianninas - Univ of OK

Gravitational Waves and Underluminous Supernovae Explosions from ELM White Dwarfs

Extremely low mass (ELM) white dwarfs have masses < 0.25 Msol and represent the end point of the evolution of compact binary systems. They are the possible progenitors of type Ia supernovae, .Ia supernovae, AM CVn systems, and are sources of gravitational waves. The nature of these short period systems (P < 1 day) also gives rise to physical phenomena such as ellipsoidal variations due to tidal distortions and Doppler beaming, not to mention the detection of pulsations and eclipsing systems. These effects are important as they provide completely independent measurements of fundamental parameters such as the stellar radius and mass. I will present a progress report on our ongoing efforts to discover, analyze and understand these extreme stellar remnants through the ELM survey. In particular, I will present our latest results for the entire ELM survey sample and discuss 2 unique systems, the eclipsing system J0651 and the metal-rich J0745.