Displaying report 1-1 of 1.
Reports until 18:32, Wednesday 23 July 2014
H1 SUS
jeffrey.kissel@LIGO.ORG - posted 18:32, Wednesday 23 July 2014 (12956)
H1 SUS BS -- Free After Wire Baffle Install TFs Look Good*
J. Kissel, S. Aston, A. Pele, B. Weaver, T. Sadecki

Looking to get a "did the new baffles screw up the suspension?" answer sooner, rather than later, Betsy and Travis unlocked H1 SUS BS and and I ran a full suite of transfer functions. The results looked reasonably clean, except for some reduced Qs on the first L/T/P modes, and an out-standing mode at 1.69 [Hz] in vertical (see first attachment). 

With the "undamped ISI!" bug in my ear from SR3, and the help of the notes in the "plotall" comparison script, 
${SusSVN}/sus/trunk/BSFM/Common/MatlabTools/plotallbsfm_tfs_M1.m
we recalled that we've seen this same feature 1.69 [Hz] before on a BSFM when the SEI system was free, but undamped (see LHO aLOG 7305). Sure enough, the SEI system had been tripped since who-cares-when during the measurement. A follow-up measurement of V to V with the SEI system back online (with HPI "pos" loops ON, and ISI damped), the 1.69 [Hz] mode disappeared (see second attachment), and Qs were restored on the lowest modes (not shown -- I only captured a T to T before being interrupted by Jim who has priority).

Apologies for the errant calibration on the single, good-looking, V to V TF -- I went to fix it after I found the error, but the site has lost connection with it's Matlab license server. #facepalm

We will assess again, officially, after first contact is removed -- but the new baffles are free of the suspension, or vice versa.

Note: I've created a new script,
${SusSVN}/sus/trunk/BSFM/Common/MatlabTools/plotbsfm_dtttfs_M1_singleDOF.m
to create the second attachment, for those times when we only have time for a before-and-after DTT TF in one DOF such as this.

Today's data:

2014-07-23_1841_H1SUSBS_M1_L_WhiteNoise.xml
2014-07-23_1841_H1SUSBS_M1_P_WhiteNoise.xml
2014-07-23_1841_H1SUSBS_M1_R_WhiteNoise.xml
2014-07-23_1841_H1SUSBS_M1_T_WhiteNoise.xml
2014-07-23_1841_H1SUSBS_M1_V_WhiteNoise.xml
2014-07-23_1841_H1SUSBS_M1_Y_WhiteNoise.xml

2014-07-23_2313_H1SUSBS_M1_T_WhiteNoise.xml
2014-07-23_2313_H1SUSBS_M1_V_WhiteNoise.xml

where the latter two files are while the ISI was damped (and the V file is what's used for the second attachment).
Non-image files attached to this report
Displaying report 1-1 of 1.