"- Often, in the literature, we can find a parameter reported to evaluate the quality of a QPO signal. It is defined in Fourier space: $Q = f/\\Delta f$.\n",
"\n",
"- Given an observing length $T$, at a given frequency $f$, we can have $N = f * T$ oscillations during our observations. Since the frequency resolution is, as we have seen, $\\Delta f \\ge 1/T$ it turns out that the \"quality factor\" is always $Q \\le N$."
