Left: parametric regions of the wave damping enhancement (I), suppression (II), and thermal over-stability (III). Grey-shaded regions indicate the values of τ_1, 2 where the q-factor is in between 1 (the green line) and 2 (the blue line, Ia), and in between 2 and 3 (the purple line, Ib). The red, green, and blue symbols indicate some arbitrary values of τ_1, 2 chosen for the numerical solutions shown in Fig. 4. Right: heating/cooling times τ_1, 2 (see Eq. (6), black and red contours, respectively) determined for the CHIANTI radiative cooling, and the heating function in the form H(ρ, T) ∝ ρ^aT^b for the varying temperature and density power indices a and b. The grey-shaded areas indicate the values of a and b where 1 < q-factor < 2 (light grey) and 2 < q-factor < 3 (dark grey). The green, blue, and purple lines show q-factor equals 1, 2, and 3, respectively.