Slices through the input limit spectrum (black) and observational spectrum averaged over one Carrington rotation (gray), which was used to obtain the input parameters, at θ = 0 and a few different values of k. Vertical dashed lines indicate the fitting ranges and the models are plotted only within these ranges. Lower limits for all k are fixed at 0.4 mHz, while the upper limits depend on the initial guess for each k, and they are the highest peak frequencies plus the widths of the peak. For the cases of ℓ = 328 and 492 (k_pix = 14 and 21, respectively), the peaks with the radial order, n, from 0 to 7 are used in the fitting, while for the case of ℓ = 984 (k_pix = 42), 0 ≤ n ≤ 3.