Tonight we worked at the optimization of the TCS working point, tuning accordingly the ITF alignment working point step by step. Hereafter a short summary of what we did (a longer and more detailed log will be posted tomorrow):
- started with the TCS OFF and locked the ITF in LN3. The BS loop was left open.
- switched on both the DASes at lower values with respect to the previous ones. The BS loop was closed after we found a good working point
- increased the power on the WI DAS
- switched off the WI DAS
- switched back on the WI DAS and increased the power on the NI outer ring
We optimized the alignment working point by maximizing the sidebands on B4 and minimizing B1p. The new values of the offsets have been saved in metatron. The CMRF seemed to improve a bit when the NI outer ring was switched on, but it was not possible to find an alignment working point minimizing the CMRF at the same time.