ON THE KELVIN-HELMHOLTZ INSTABILITY OF THE NOSE PART OF THE HELIOPAUSE .1. AXISYMMETRICAL DISTURBANCES

The Kelvin-Helmholtz instability of the nose part of the heliopause wi th respect to linear axisymmetric disturbances is investigated in the short-wavelength approximation. The solar wind and interstellar medium flows in this region are considered to be incompressible. An evolutio n equation containing the effects of curvature of the heliopause and n onuniformity of the velocity field is derived. Growth rates of unstabl e disturbances propagating along the nose part of the heliopause are s hown to be smaller then those in the case of a plane tangential discon tinuity divided two uniform incompressible fluids.