Gravitational Radiation, Inspiraling Binaries, and Cosmology
**Previous
abstract** **Next
abstract**

**Session 67 -- Cosmology and Distance Indicators**
*Oral presentation, Thursday, January 13, 2:15-3:45, Crystal Forum Room (Crystal City Marriott)*

## [67.05] Gravitational Radiation, Inspiraling Binaries, and Cosmology

*L.S.Finn (Northwestern University), D.F.Chernoff (Cornell University)*
We show how to measure cosmological parameters using observations
of inspiraling binary neutron star or black hole systems in one
or more gravitational wave detectors. To illustrate, we focus on
the case of fixed mass binary systems observed in a single Laser
Interferometer Gravitational-wave Observatory (LIGO)-like
detector. Using realistic detector noise estimates, we
characterize the rate of detections as a function of a threshold
signal-to-noise ratio $\rho_0$, the Hubble constant $H_0$, and
the binary ``chirp'' mass. For $\rho_0 = 8$, $H_0 = 100\,\mbox{km
s}^{-1}
\mbox{Mpc}^{-1}$, and $1.4 \mbox{M}_{\sun}$ neutron star
binaries, the anticipated sample has a median redshift of
$0.22$. Under the same assumptions but independent of $H_0$, a
conservative rate density of coalescing binaries
($8\times10^{-8}
\,\mbox{yr}^{-1}
\,\mbox{Mpc}^{-3}$) implies LIGO
will observe $\sim 50\,\mbox{yr}^{-1}$ binary inspiral events.

The precision with which $H_0$ and the deceleration parameter
$q_0$ may be determined depends on the number of observed
inspirals. For fixed mass binary systems, $\sim 100$
observations with $\rho_0 = 10$ in the LIGO detector will give
$H_0$ to 10\% in an Einstein-DeSitter cosmology, and 3000 will
give $q_0$ to 20\%. For the conservative rate density of
coalescing binaries, 100 detections with $\rho_0 = 10$ will
require about 4~yrs.

**Thursday
program listing**