From August 11th 2011 07:00 UTC to August 18th 08:00 UTC, the glitches associated to the fluctuating line around 2 kHz have disappeared (see plots 1,2,3,4). Plot 5 shows the spectrogram of Pr_B1_ACp_diff23 where a fluctuating line is present around 2 kHz while it is absent in Pr_B1_ACp. Plot 6 shows the spectrogram of Pr_6MHz_ACq which is noisier during this less glitchy period. There also some hint of change in Em_RFBDCE01_tmp spectrogram but it is less evident. No other spectrogram shows any change during this period.

The 2 kHz line and the glitches disappeared in coincidence with B1 phases changes by Gabriele (elog 30081 and 30082). The glitches reappeared in coincidence with "B1 setup moved back to External Detection Bench" by Gabriele and Julien (elog 30123 and 30124).

This may give some hint for an action to remove the 2 kHz glitches which represent about 30% of the HF glitches.