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Updated: Jun 23, 2026
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A 100 KW Class Applied-field Magnetoplasmadynamic Thruster
Published on: December 22, 2018
Hydrodynamical trigger mechanism for pulsar glitches.
Kostas Glampedakis1, Nils Andersson
1SISSA/International School for Advanced Studies and INFN, via Beirut 2-4, 34014 Trieste, Italy.
Physical Review Letters
|April 28, 2009
Summary
A new superfluid instability in spinning neutron stars can cause vortex unpinning, transferring angular momentum to the crust. This model aligns with observed neutron star glitch data.
Area of Science:
- Astrophysics
- Nuclear Physics
- Condensed Matter Physics
Background:
- Neutron stars are rapidly spinning remnants of supernovae.
- Superfluidity in neutron star cores is crucial for understanding their rotational dynamics.
- Observed 'glitches' in neutron star rotation suggest sudden changes in angular momentum transfer.
Purpose of the Study:
- To introduce and describe a novel instability mechanism in superfluid neutron stars.
- To explain the global unpinning of vortices and its effect on angular momentum transfer.
- To provide a theoretical model that explains observed neutron star glitch phenomena.
Main Methods:
- Development of a simple theoretical model for superfluid neutron stars.
- Analysis of the role of inertial r-modes in the instability.
- Comparison of model predictions with observational data from neutron star glitches.
Main Results:
- Identification of a new instability triggered by critical rotational lag.
- Demonstration of angular momentum transfer from the superfluid to the crust.
- Successful agreement of the model with observed neutron star glitch data.
Conclusions:
- The proposed instability offers a plausible explanation for neutron star glitches.
- Further research should incorporate crustal shear stresses and magnetic fields for more comprehensive models.
- This work stimulates new avenues for theoretical and observational studies of neutron stars.
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