NAOJ GW Elog Logbook 3.2
Michael and Yuhang
Yesterday, we locked AA, Zcorr, pointing and CCFC and performed a FDS measurment. The lock last for almost one hour. 6 measurements were performed during this time (with a separation of almost 10min).
The result is shown in the attached figure 1.
Within this 1 hour, all measurements overlap very well. Even the low frequency back scattering seems to be more stable.
(50:50 BS was used for CCSB pick-off. 30mW pump power is used for SQZ production.The detuning was expected to be 104Hz according to elog2353.)
(Figure 2 shows a FDS measurement of detuning smaller than 100Hz, it seems backscattering makes FDS not reaching shot noise level. This is also why we took several measurement with higher detuning.)
(Figure 3 shows a fit for higher detuning. Since the detected detuning is 145Hz, we expect all the frequencies to be increased by 40Hz in elog2353. )