at high density limit. That of $\bar{\nu}_e$ is the smallest. The flavor conversion between $\nu_e$ ($\bar{\nu}_3$) and $\bar{\nu}_{\mu,\tau}$ ($\nu_3$) occurs at RSF-H resonance. We see MSW-H and MSW-L resonances similar to the case of $Y_e = 0.49$. There is no resonance corresponding to RSF-L or RSF-X resonance. This is due to a nonlinear dependence of the squared masses on the density.

The correspondence between flavor and mass eigenstates at the high density limit is recognized using the effective potentials. The effective potential of $\nu_e$ is $$V_{\nu_e} = \frac{\sqrt{2}}{2} G_F \frac{\rho}{m_u} (3 Y_e -1) .$$ That of $\bar{\nu}_{\mu,\tau}$ is $$V_{\bar{\nu}_{\mu,\tau}} = \frac{\sqrt{2}}{2} G_F \frac{\rho}{m_u} (1 -Y_e) .$$ The satisfying inequalities hold: $V_{\nu_e} < V_{\bar{\nu}_{\mu,\tau}}$ for $Y_e < 0.5$ and $V_{\nu_e} > V_{\bar{\nu}_{\mu,\tau}}$ for $Y_e > 0.5$. Therefore, the effective squared mass of $\nu_e$ is the largest at the high density limit in $Y_e > 0.5$. In the case of $Y_e = 0.5$, the equality $V_{\nu_e} = V_{\bar{\nu}_{\mu,\tau}}$ is satisfied and there are no RSF-H and RSF-L resonances.

Figure 3 shows the density dependence of the effective squared masses in the inverted mass hierarchy. In the case of $Y_e = 0.49$, $\nu_e$ and $\bar{\nu}_e$ correspond to the mass eigenstates $\nu_1$ and $\bar{\nu}_1$, 