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Radio-quiet neutron star 1E 1207.4-5209: a possible strong gravitational-wave source
1Department of Astronomy, Nanjing University, People's Republic of China.
Physical Review Letters
|February 21, 2006
Summary
Pulsar 1E 1207.4-5209
Area of Science:
- Astronomy
- Astrophysics
- Pulsar research
Background:
- The pulsar 1E 1207.4-5209 presents four significant puzzles.
- These include age discrepancies, magnetic field inconsistencies, non-monotonic spin-down, and variable frequency derivative.
Purpose of the Study:
- To propose a unified explanation for the four observed puzzles of pulsar 1E 1207.4-5209.
- To investigate the potential of this pulsar as a source for gravitational-wave detectors.
Main Methods:
- Analysis of pulsar spin-down properties.
- Modeling of binary system interactions.
- Gravitational wave amplitude calculations.
Main Results:
- An ultracompact binary system with a 0.5–3.3 min orbital period can resolve all four puzzles.
- The pulsar system is located at a close distance of 2 kpc.
- A characteristic gravitational wave amplitude of approximately 3 x 10(-21) is predicted.
Conclusions:
- The ultracompact binary model provides a natural explanation for the observed anomalies of pulsar 1E 1207.4-5209.
- This system represents a promising target for future gravitational-wave observatories like the Laser Interferometer Space Antenna.
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