Search for gravitational waves from intermediate mass binary black holes

We present the results of a weakly modeled burst search for gravitational waves from mergers of nonspinning intermediate mass black holes in the total mass range $100–450{\mathrm{M}}_{\odot }$ and with the component mass ratios between $1:1$ and $4:1$. The search was conducted on data collected by the LIGO and Virgo detectors between November of 2005 and October of 2007. No plausible signals were observed by the search which constrains the astrophysical rates of the intermediate mass black holes mergers as a function of the component masses. In the most efficiently detected bin centered on $88+88{\mathrm{M}}_{\odot }$, for nonspinning sources, the rate density upper limit is 0.13 per ${\mathrm{Mpc}}^3$ per Myr at the 90% confidence level.

Figure 1

False alarm density rate vs $\eta$ for the background events (H1H2L1V1—solid line, H1H2L1—dashed line) and the foreground events (H1H2L1V1—black squares, H1H2L1—open squares).

Figure 2

The effective range $R_{\mathrm{eff}}$ in Mpc (values and white-gray scale) per component mass bin: H1H2L1V1 (left plot), H1H2L1 (right plot). The overall uncertainty on the ranges quoted here is 20%. IMBH systems with mass ratios of greater than $4:1$ are excluded since their waveforms are not verified with the NR calculations.

Figure 3

The rate density upper limits in ${\mathrm{Mpc}}^{-3}{\mathrm{Myr}}^{-1}$ (values and white-gray scale) calculated over the component mass plane. These rate limits include all sources of error.