Flute Instability Effects for Disk Accretion onto Neutron Stars with Strong Magnetic Fields

Abstract

The flute instability at the inner edge of a thin diamagnetic accretion disk is analyzed. The magnetic field configuration model from Aly (1980) is used. We have analyzed a modified dispersion relation for the flute instability that takes into account the Keplerian disk rotation. We have derived the inner radius of the accretion disk within our analysis of the flute instability. We show that the inner radius does not differ from the Alfvén radius for spherical accretion to within a dimensionless coefficient, with the proportionality coefficient depending only on the turbulence alpha parameter and the relative disk thickness (\(h/r\)).