(a) Mach 1.2

(b) Mach 1.5

(c) Mach 2.0

(d) Mach 2.5

 Diffusion of contact discontinuity in shock contact interaction problem in 2D case : Variation of growth rates with  Mach numbers. Plots are for resolution 0.001 taking a slice at y/ymax = 0.5