Peak bagging analysis of the low-luminosity RGB star KIC 6117517 by degrading the frequency resolution of the stellar PSD. Left panels: échelle diagrams obtained for four different frequency resolutions, with same description as in Fig. 15. The literature frequencies and the folding Δν value are those by C15. Right panels: three most central chunks of the stellar PSD (in gray) as seen from GLOBAL for each test performed, with ℓ = 2, 0 regions in yellow. The purple arrows mark the position of ν_max obtained from a background fit to each test PSD. Only global radial mode frequencies are indicated (vertical dotted lines). The smoothing of the PSD is coinciding with the PSD itself for the two bottom panels because of the low frequency resolution.