[Cheryl V., Chris M., Kiwamu I., Keita K., Michael R., Rick S., Paul F.]

This afternoon the input modecleaner was locked!

Effectively the same feedback filters as in L1 were used.  The lock was achieved as soon as the VCO feedback path was enabled, at a visibility of roughly 70%. This is shown in the attached stime series; the first lock occurred at around GPS time 1041991500. Soon after, the alignment was adjusted to try to improve the visibility, probably causing the loss of lock. After relocking, the alignment was adjusted, bringing the visibility to around 94%.

One of the LVEA cameras is currently pointing at a TV monitor which shows the IMC_REFL beam (a very temporary solution until we can get the signal directly to the control room). The embedded youtube video shows the IMC_REFL beam at the best visibility so far achieved.

The second attached file shows the power spectrum of the PSL frequency control signal, calibrated in the same way as for L1. The character of the H1 IMC and L1 IMC frequency feedback signals are quite different below about 60Hz. Next week we can look at this, and many more features of the locked IMC, in more detail.