We use data from the second science run of the LIGO gravitational-wave detectors to search for the gravitational waves from primordial black hole binary coalescence with component masses in the range 0.2–1.0M⊙. The analysis requires a signal to be found in the data from both LIGO observatories, according to a set of coincidence criteria. No inspiral signals were found. Assuming a spherical halo with core radius 5 kpc extending to 50 kpc containing nonspinning black holes with masses in the range 0.2–1.0M⊙, we place an observational upper limit on the rate of primordial black hole coalescence of 63 per year per Milky Way halo (MWH) with 90% confidence.
Diaz, Mario C.; Johnston, Wm. R.; Mukherjee, Soma; Mohanty, Soumya; and Torres, Cristina V., "Search for gravitational waves from primordial black hole binary coalescences in the galactic halo" (2005). Physics and Astronomy Faculty Publications and Presentations. 348.
Physical Review D