Stabilization of the flute oscillation first mode in a long axisymmetric open magnetic trap

The first mode of plasma flute instability with β << 1 in the trap with a simple mirror field-shift of the plasma filament as a whole - can be suppressed if the trap is connected with a circular axially-symmetric trap filled with plasma so that there exists a rather sharp maximum of the magnetic field outside the external boundary of bell-shaped plasma in the circular trap. If in this case the simple magnetic mirror is so long that all the rest flute modes are stabilized by the effect of final Larmor radius then plasma turns to be stable relatively to flute perturbations