Gravitational-Wave Lensing Fringes by Compact Dark Matter at LIGO [CEA]

Utilizing gravitational-wave (GW) lensing opens a new way to understand the history and structure of the universe. In spite of coarse angular resolution and short duration of observation, we show that LIGO can detect the GW lensing induced by small structures, in particular by compact dark matter (DM) of $10 – 10^5 M_{\rm sun}$, which remains an interesting DM candidate. The lensing is detected through GW frequency chirping, creating the natural and rapid change of lensing patterns: frequency-dependent amplification and modulation of waveforms. As a highest-frequency GW detector, LIGO is a unique GW lab to probe such light compact DM. With design sensitivity of Advanced LIGO, one-year observation can detect as many as 1000 lensed GWs and constrain compact DM fraction as small as $f_{\rm DM} \gtrsim 10^{-3}$.

Read this paper on arXiv…

S. Jung and C. Shin
Wed, 6 Dec 17

Comments: 6 pages, 5 figures