Hydrogen-only Saha equation
= Hydrogen-only Saha equation
When $Y_p=0$, $\mathcal F=X_{H^+}$, and
$$
\frac{X_{H^+}^2}{1-X_{H^+}}
=\frac1{n_B}\left(\frac{2\pi m_ek_BT}{h^2}\right)^{3/2}
e^{-I_H/(k_BT)}.
$$
= Hydrogen-only Saha equation
When $Y_p=0$, $\mathcal F=X_{H^+}$, and
$$
\frac{X_{H^+}^2}{1-X_{H^+}}
=\frac1{n_B}\left(\frac{2\pi m_ek_BT}{h^2}\right)^{3/2}
e^{-I_H/(k_BT)}.
$$