Profiles of Γ₁ and l/r in the envelopes of the canonical TPAGB star (cyan solid line) and the cases with all three effects included and a = 10 R_⊙ (blue solid line), 20 R_⊙ (green dashed line), 40 R_⊙ (red dash-dot line), and 80 R_⊙ (black dotted line) at a time between two thermal pulses (t = 3500 yr). The horizontal dashed line in panel a is the critical . Panels b and c are similar, but for different widths of transition region.