Virgo Logbook

AdV-COM (AdV commissioning (1st part) )

Allocca, chiummo, Fiori - 9:34 Wednesday 07 June 2017 (37875)

Preparation for noise injections on DET tower

As follow-up of the tapping test investigations we are performing these days, we prepared -yesterday around noon- the setup to shake the West flange of the DET tower, a spot that showed some sensitivity (see 37856).

In the first picture there is the shaker installed so to shake the West DET tower flange along z, and the accelerometer (closer to the flange center) that will be used to monitor the vibration. This accelerometer is the one formerly sitting on the finger of the DET small cryotrap, measuring along y (see second picture). Its position will be restored after a clean injection is performed.

The injections foreseen by yesterday night were long prevented by the issues of the lock acquisition described in 37871.

Images attached to this report

Comments to this report:

martynov - 22:15 Wednesday 07 June 2017 (37884)

Since OMC RIN at 300 - 1000 Hz is flat in frequency, we should expect that accelerometer signal should grow as f^2 in units of [m/s^2]. With the current location of accelerometers, only a few channels satisfy this requirement. All of them are located on the cryostats (see attached plot). It would be useful to excite all of them with a shaker.

Non-image files attached to this comment

gddcanvas.pdf

fiori - 15:54 Friday 09 June 2017 (37925)

To be consistent the accelerometer that os now temporarely on DT West flange for the purpose of noise injections has been renamed:

ENV_DT_W_FLANGE_ACC_Z

(consequently channel ENV_DT_CT_FINGER_Y is temporarely unavailable)