6 research outputs found
LISA observations of massive black hole mergers: event rates and issues in waveform modelling
The observability of gravitational waves from supermassive and
intermediate-mass black holes by the forecoming Laser Interferometer Space
Antenna (LISA), and the physics we can learn from the observations, will depend
on two basic factors: the event rates for massive black hole mergers occurring
in the LISA best sensitivity window, and our theoretical knowledge of the
gravitational waveforms. We first provide a concise review of the literature on
LISA event rates for massive black hole mergers, as predicted by different
formation scenarios. Then we discuss what (in our view) are the most urgent
issues to address in terms of waveform modelling. For massive black hole binary
inspiral these include spin precession, eccentricity, the effect of high-order
Post-Newtonian terms in the amplitude and phase, and an accurate prediction of
the transition from inspiral to plunge. For black hole ringdown, numerical
relativity will ultimately be required to determine the relative quasinormal
mode excitation, and to reduce the dimensionality of the template space in
matched filtering.Comment: 14 pages, 2 figures. Added section with conclusions and outlook.
Matches version to appear in the proceedings of 10th Annual Gravitational
Wave Data Analysis Workshop (GWDAW 10), Brownsville, Texas, 14-17 Dec 200
Phenomenological template family for black-hole coalescence waveforms
Recent progress in numerical relativity has enabled us to model the
non-perturbative merger phase of the binary black-hole coalescence problem.
Based on these results, we propose a phenomenological family of waveforms which
can model the inspiral, merger, and ring-down stages of black hole coalescence.
We also construct a template bank using this family of waveforms and discuss
its implementation in the search for signatures of gravitational waves produced
by black-hole coalescences in the data of ground-based interferometers. This
template bank might enable us to extend the present inspiral searches to
higher-mass binary black-hole systems, i.e., systems with total mass greater
than about 80 solar masses, thereby increasing the reach of the current
generation of ground-based detectors.Comment: Minor changes, Submitted to Class. Quantum Grav. (Proc. GWDAW11
Proposal for gravitational-wave detection beyond the standard quantum limit through EPR entanglement
Proposal for gravitational-wave detection beyond the standard quantum limit through EPR entanglement
The Standard Quantum Limit in continuous monitoring of a system is given by
the trade-off of shot noise and back-action noise. In gravitational-wave
detectors, such as Advanced LIGO, both contributions can simultaneously be
squeezed in a broad frequency band by injecting a spectrum of squeezed vacuum
states with a frequency-dependent squeeze angle. This approach requires setting
up an additional long base-line, low-loss filter cavity in a vacuum system at
the detector's site. Here, we show that the need for such a filter cavity can
be eliminated, by exploiting EPR-entangled signal and idler beams. By
harnessing their mutual quantum correlations and the difference in the way each
beam propagates in the interferometer, we can engineer the input signal beam to
have the appropriate frequency dependent conditional squeezing once the
out-going idler beam is detected. Our proposal is appropriate for all future
gravitational-wave detectors for achieving sensitivities beyond the Standard
Quantum Limit.Comment: 16 pages, 7 figure