Superfluid Turbulence and Pulsar Glitch Statistics

Abstract

Experimental evidence is reviewed for the existence of superfluid turbulence in a differentially rotating, spherical shell at high Reynolds numbers (Re greater than or similar to 10(3)), such as the outer core of a neutron star. It is shown that torque variability increases with Re, suggesting that glitch activity in radio pulsars may be a function of Re as well. The Re distribution of the 67 glitching radio pulsars with characteristic ages tau(c) = 1-3.9 x 10(-3). The conclusion holds for ( modified) Urca and nonstandard cooling, and for Newtonian and superfluid viscosities.