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Measurement of gravitational spin-orbit coupling in a binary-pulsar system
I H Stairs1, S E Thorsett, Z Arzoumanian
1Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1, Canada. stairs@astro.ubc.ca
Physical Review Letters
|November 5, 2004
Summary
Spinning pulsars exhibit relativistic gravity effects like precession and aberration as they orbit companion stars. Observations of PSR B1534+12 confirm these effects, aligning with general relativity predictions.
Area of Science:
- Astronomy
- Astrophysics
- General Relativity
Background:
- Pulsars are rapidly rotating neutron stars emitting beams of radiation.
- In binary systems, pulsars orbit compact companion stars, leading to relativistic effects.
Purpose of the Study:
- To measure the precession of a spinning pulsar (PSR B1534+12) due to relativistic gravity.
- To detect special-relativistic aberration of the pulsar beam caused by orbital motion.
- To determine system geometry and test general relativity predictions.
Main Methods:
- Observing the average shape and polarization of radiation from PSR B1534+12.
- Analyzing pulsar beam aberration due to orbital motion.
Main Results:
- Measured the effect of pulsar precession on radiation.
- Detected pulsar beam aberration with limited precision.
- Fixed system geometry, including spin-orbit misalignment.
- Measured a precession time scale consistent with general relativity.
Conclusions:
- The observed precession and aberration effects in PSR B1534+12 validate predictions of general relativity.
- The study provides precise constraints on the geometry of relativistic pulsar systems.
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