Folded PS in normalized units in the case of Δν = 29.56 μHz. The overlaid ridges represent the result for ℓ = 2,0,1 mode degrees as derived by a least-squares fit to the asymptotic relation, which are marked as dotted, dashed and dot-dashed lines, respectively. The daily side-lobes for  ± 11.57 in the case of ℓ = 0,2 are also clearly visible and marked with the same line-style for each mode degree.