# Star Opacity and Balmer Break

desperate_student
Homework Statement:
Write an expression for κ(3647+)/κ(3647−), the ratio of the opacities just above and below the Balmer break for (i) low-temperature atmospheres where the opacity above the Balmer break is due to the H− ion, and (ii) high-temperature atmospheres where the opacity above the Balmer break is due to the n = 3 level of neutral hydrogen. Your results should show that at low temperatures, the Balmer discontinuity depends on both temperature and electron pressure, while at high temperature, it depends only on temperature.
Relevant Equations:
Saha Equation, Boltzmann Equation, Kramers Opacity for free-free and free-bound and any other relevant equations.
I am not sure where to start for this. Considering it needs to be demonstrate Balmer Break, I am assuming it needs to be wavelength based. As a result I am assuming I cannot use mean (Kramers) Opacity but rather express in terms of Opacity k= n*sigma/rho.
My thoughts are to use Boltzmann Equation to obtain n_h,n=2,3 and Saha Equation to find n_h- and sub into n*sigma/rho and find k ratio based on that