a follow-up of Irene's post (29458). I attach the time-frequency plot since May 10 and two distributions, the first one calculated on the data up to May 24 and the second from May 24 to yesterday.
It seems that in the last days the 23Hz line is much more persistent; the +-0.2 Hz sidebands look more or less the same (persistency 0.06); furthermore, you can see new small lines, roughly equally spaced by ~0.05 Hz.
Alberto
