Hello everybody, I am new on this website and I hoppe I choosed the right section. If I am correct, the linewidth of a resonator 2Δf must be defined by the product of its damping rate γ and its resonance frequency f : 2Δf = 2.γ.f In my case, I want to consider a strongly nonlinear oscillator, the frequency varies a lot with the oscillation amplitude. I already know that this nonlinearity will increase a lot the linewidth of the power spectra. I wonder if such large the nonlinearity can also affect the linewidth of the oscillator when it is not excited (it becomes a resonator), and then be higher than 2.γ.f. If you have seen this problem in any type of system I would be very happy :) Thank you very much in advance !