L. S. Finn

LIMITS ON THE STOCHASTIC GRAVITATIONAL WAVE BACKGROUND FROM THE NORTH AMERICAN NANOHERTZ OBSERVATORY FOR GRAVITATIONAL WAVES

We present an analysis of high-precision pulsar timing data taken as part of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) project. We have observed 17 pulsars for a span of roughly five years using the Green Bank and Arecibo radio telescopes. We analyze these data using standard pulsar timing models, with the addition of time-variable dispersion measure and frequency-variable pulse shape terms. Sub-microsecond timing residuals are obtained in nearly all cases, and the best rms timing residuals in this set are ~30-50 ns. We present methods for analyzing post-fit timing residuals for the presence of a gravitational wave signal with a specified spectral shape. These optimally take into account the timing fluctuation power removed by the model fit, and can be applied to either data from a single pulsar, or to a set of pulsars to detect a correlated signal. We apply these methods to our data set to set an upper limit on the strength of the nHz-frequency stochastic supermassive black hole gravitational wave background of h_c (1 yr^(–1)) < 7 × 10^(–15) (95%). This result is dominated by the timing of the two best pulsars in the set, PSRs J1713+0747 and J1909–3744.

Observing binary inspiral in gravitational radiation: One interferometer

Close binary systems of compact objects with less than ten minutes remaining before coalescence are readily identifiable sources of gravitational radiation for the United States Laser Interferometer Gravitational-Wave Observatory (LIGO) and the French-Italian VIRGO gravitational-wave observatory. As a start toward assessing the full capabilities of the LIGO-VIRGO detector network, we investigate the sensitivity of individual LIGO-VIRGO-like interferometers and the precision with which they can determine the characteristics of an inspiralling binary system. Since the two interferometers of the LIGO detector share nearly the same orientation, their joint sensitivity is similar to that of a single, more sensitive interferometer. We express our results for a single interferometer of both initial and advanced LIGO design, and also for the LIGO detector in the limit that its two interferometers share exactly the same orientation. We approximate the secular evolution of a binary system as driven exclusively by its leading-order quadrupole gravitational radiation. Observations of a binary in a single interferometer are described by four characteristic quantities: an amplitude

The last three minutes: Issues in gravitational-wave measurements of coalescing compact binaries

\mathcal{A}

Detection, measurement, and gravitational radiation.

, a chirp mass

Bounding the mass of the graviton using binary pulsar observations

\mathcal{M}

Gravitational waves from a compact star in a circular, inspiral orbit, in the equatorial plane of a massive, spinning black hole, as observed by LISA

, a time

Determining gravitational radiation from Newtonian self-gravitating systems

T

Detecting an association between gamma-ray and gravitational wave bursts

, and a phase

Black Hole Spectroscopy: Testing General Relativity through Gravitational Wave Observations

\ensuremath{\psi}

Binary inspiral, gravitational radiation, and cosmology

. We find the amplitude signal-to-noise ratio (SNR)