Hyperon bulk viscosity is the most significant transport coefficient affecting the growth or decay of any neutron-star mode of oscillation which has, even to second order in its amplitude, a periodic density fluctuation. This paper evaluates both the direct Urca and strangeness-changing four-baryon weak-interaction terms in the coefficient.

No abstract

The properties of tectonic earthquake sources are compared with those deduced here for fault planes in solid neutron-star matter. The conclusion that neutron-star matter cannot exhibit brittle fracture at any temperature or magnetic field strength is significant for current theories of pulsar glitches, and of the anomalous X-ray pulsars and soft-gamma repeaters.

The transition to a type II proton superconductor which is believed to occur in a cooling neutron star is accompanied by changes in the equation of hydrostatic equilibrium and by the formation of proton vortices with quantized magnetic flux. Analysis of the electron Boltzmann equation for this system and of the proton supercurrent distribution formed at the transition leads to the derivation of a simple expression for the transport velocity of magnetic flux in the liquid interior of a neutron star. This shows that flux moves easily as a consequence of the interaction between neutron and proton superfluid vortices during intervals of spin‐down or spin‐up in binary systems. The differences between the present analysis and those of previous workers are reviewed and an error in the paper of Jones is corrected.

No abstract