Over the past two days, B&K hammering measurements have been carried out on the ITMX and ETMX.

For the two measurements, the suspensions were fully payloaded, vibration absorbers were mounted on the structure, and the ISI was still locked.

A tri-axis accelerometer has been mounted on the corner of the structure, and the hit was given with a hammer at two different locations (front and side) as showed on the two pictures attached (1) for ITMX and (2) for ETMX. The pls template SimpleHammerDisplay3 from T1000697 was used to take the data, with a force threshold set at 10N.

Plots in "2013-09-13_H1ETMX_H1ITMX_ISI_Locked.pdf " are showing a comparison between the results for H1 ETMX, H1 ITMX, and L1 ITMY X resp to X exc on the 1st plot and Y resp to Y exc on the 2nd plot. The main resonnance below 150 Hz is well damped in both directions, for both suspensions.

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Data (ascii and pls files) are located in /QUAD/H1/${ETMX/ITMX}/BandK, plotting script (BandK_plot.m) is located in /Common/Matlabtools/, and pdf results are located in /Common/Data/BandK. They have been commited to the svn.