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2008

Gravitational waves

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Full-Text Articles in Physics

Towards A Fully Nonlinear Cauchy Characteristic Extraction, Maria Babiuc-Hamilton Sep 2008

Towards A Fully Nonlinear Cauchy Characteristic Extraction, Maria Babiuc-Hamilton

Physics Faculty Research

The artificial finite outer boundary present in Cauchy codes introduce two sources of error: The outer boundary condition and waveform extraction at an inner worldtube. The problem of proper boundary condition for a radiating system can be solved only by extension to Ι+ (conformal compactification). Cauchy Characteristic Extraction (CCE) offers a means to avoid these errors.


Beating The Spin-Down Limit On Gravitational Wave Emission From The Crab Pulsar, Ligo Scientific Collaboration, Nelson Christensen, Jan 2008

Beating The Spin-Down Limit On Gravitational Wave Emission From The Crab Pulsar, Ligo Scientific Collaboration, Nelson Christensen,

Faculty Work

We present direct upper limits on gravitational wave emission from the Crab pulsar using data from the first nine months of the fifth science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). These limits are based on two searches. In the first we assume that the gravitational wave emission follows the observed radio timing, giving an upper limit on gravitational wave emission that beats indirect limits inferred from the spin-down and braking index of the pulsar and the energetics of the nebula. In the second we allow for a small mismatch between the gravitational and radio signal frequencies and interpret …