Gravitational wave verification sources

Abstract

Ultra-compact binary systems containing white dwarfs dominate the gravitational wave foreground in the mHz frequency range. Many of these binaries are weak gravitational wave sources. However, there are nine systems where the gravitational wave strain is strong enough to make them verification sources for gravitational wave missions, e.g. the evolved Laser Interferometer Space Antenna (eLISA). Here we present a summary of the physical characteristics of these nine systems, including the observed rate of orbital decay. In addition, we present the recent discoveries from the ELM Survey, which identified two verification sources in the last 3 years. We also discuss the future prospects for increasing the sample of verification binaries.