A. Effler, J. Kissel

Attached is a comparison between the first two aLIGO BSFMs built. Encouragingly, the look strikingly similar!

The most significant difference is in Pitch (who's surprised?), where the first pitch mode for L1 SUS BSFM06 is 0.46, and 0.47 for H2SUSFMY. If you remember, we battled quite hard to get H2 SUS FMY where it is, see 
1297
974,
and in the end, decided that the last iteration of physical parameters on H2 SUS FMY (formerly BSFM01), resulting in the pitch mode of 0.47 was good enough. Here, with BSFM06, I know that we've incorporated all of the fixed changes (wire lengths, M3 prisms), and have built the only adjustable parameter (the blade tip heights, which determine/directly effect d1) has been set to the H2 SUS FMY value of 23.6 mm. However, the DC magnitude of the pitch transfer function is lower by a bit, and the highest resonant frequency is higher at 1.51 Hz.

We must bare in mind, that these BSFM06 measurements where taken on 111112, before it was known that the oplev mirror was causing DC pitch errors. This has sense been corrected, and data is pending, see Anamaria's entry for further details.

Further comments / recommendations to come, once we see a new set off data from BSFM 06, after OpLev mirror adjustment.