- realignment of the beam into the AOM: the 1st order was optimized to 3% of the total power while the rampauto offset was set to 2.5V.
- the Pstab rampauto was swapped and tuned to have the right gain.
- the RF driver of the AOM was swapped.
Currently, PSTAB is at its nominal value (see figure 1) but undergoes some glitches (see figure 2) which corresponds to an increase of the noise of 1 to 3 orders of magnitude. This saturates the Pstab electronics which makes the power (PMC_TRA, IMC_TRA,...) to oscillate by 2-3%pp over few seconds. The origin of these glitches is still unknown but seems to be correlated with the IMC loop gain. Another test to be conducted is to use on of the 2 other photodiodes for the Pstab loop.
