SRM & SR2 Phase 3b Acceptance TFs were presented in LHO aLOG entries 17633 and 17634, however, there was an issue affecting the scaling of the plots of the lower suspension stages.

The discrepancy in the scaling was as a consequence of the recent modifications to the Triple Coil Driver actuation strength carried out only at H1 (ECR E1400369) not being taken account of in the Matlab calibration script. Therefore, I've updated the Matlab (calib_hsts.m) script to support different calibrations factors for suspensions at both sites.

The aforementioned TFs have been re-processed using the updated Matlab scripts. Measurements for each stage have been compared with similar L1 and H1 Suspensions at Phase 3b (in-vacuum), as follows:-

- SRM & SR2 M1-M1 undamped & damped results (allhstss_2015-04-09_Phase3b_H1HSTSs_M1_D*_ALL_ZOOMED_TFs.pdf)
- SRM & SR2 M2-M2 undamped & damped results (allhstss_2015-04-09_Phase3b_H1HSTSs_M2_D*_ALL_ZOOMED_TFs.pdf)
- SRM & SR2 M3-M3 undamped & damped results (allhstss_2015-04-09_Phase3b_H1HSTSs_M3_D*_ALL_ZOOMED_TFs.pdf)

Summary:

M1-M1, undamped TFs are consistent with model and similar suspensions. Very minor shift of H1 SRM pitch modes above 3 Hz. Damped TFs demonstrate variation in damping between sites. However, just to note that H1 SRM vertical DOF peaks still remain relatively high Q.

M2-M2, both undamped and damped TFs taken are consistent with model and simialr suspensions. However, H1 SR2 can be seen to be weaker due to failed UL actuator (Integration Issue #930).

M3-M3, despite suffering poor coherence below 0.5 Hz, both undamped and damped TFs taken are very consistent with model and similar suspensions.

Therefore, these TFs raise no concerns for SRM & SR2 suspensions, other than the failed SR2 M2 stage actuator noted above.

All data, scripts and plots have been committed to the sus svn as of this entry.