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Updated: May 28, 2026
16:20
Hyperpolarized Xenon for NMR and MRI Applications
Published on: September 6, 2012
Revealing the physics of R modes in low-mass x-ray binaries
Wynn C G Ho1, Nils Andersson, Brynmor Haskell
1School of Mathematics, University of Southampton, Southampton, SO17 1BJ, United Kingdom.
Physical Review Letters
|October 11, 2011
Summary
Astrophysical constraints on neutron star r-mode instability in low-mass X-ray binaries are examined. Current models conflict with observations, suggesting a need to revise our understanding of neutron star physics.
Area of Science:
- Astrophysics
- Nuclear Physics
- Gravitational Wave Astronomy
Background:
- Accreting neutron stars in low-mass X-ray binaries are subject to gravitational-wave-driven instabilities.
- The r-mode instability is a key phenomenon affecting the evolution and observable properties of these systems.
Purpose of the Study:
- To investigate astrophysical constraints on the r-mode instability in accreting neutron stars.
- To reconcile theoretical predictions with observational data, particularly for rapidly rotating neutron stars.
Main Methods:
- Utilizing recent findings on superfluid and superconducting properties to estimate neutron star core temperatures.
- Comparing inferred core temperatures and rotation rates with theoretical r-mode instability criteria.
Main Results:
- Analysis reveals a diversity in the observed neutron star population.
- Many systems appear to be within the r-mode instability region, contradicting expectations.
- A significant disagreement exists for rapidly rotating neutron stars.
Conclusions:
- The current understanding of physics relevant to the r-mode instability is insufficient.
- Further research is required to resolve the discrepancy between theoretical models and observations.
- Reevaluation of superfluidity, superconductivity, and microphysics in neutron star cores is necessary.
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