A Gravitational Wave Source in Hiding

Mukremin Kilic (University of Oklahoma), Warren Brown (Smithsonian Astrophysical Observatory), and collaborators have recently identified one of the best (and perhaps the most powerful) gravitational wave sources – a binary white dwarf system with a 20-minute period. In this close orbit, the stars are losing angular momentum rapidly to produce gravitational waves, and the pair are predicted to merge on a timescale of less than 9 million years. This work, based on observations from Gemini North and the MMT, is described in a Gemini web feature. A preprint is also available, with the paper to be published in Monthly Notices of the Royal Astronomical Society.

Gemini time-resolved spectroscopy of H-beta lines over 45 minutes, clearly showing a 20 minute periodicity.