cms motion measurements

CMS Motion Measurements

Mechanical Measurement Lab, 2009.21.09EDMS no. 1027459

2Mechanical Measurement Lab Michael.Guinchard@cern.ch2009.09.07

Equipment

• Two geophones and the MKII acquisition system were used for the measurements.

• To measure the ground vibration, two geophones were placed close together on the floor under the detector

• To discover the behaviour of different parts of the experiment reference geophone was placed on the ground and other one was placed on the appropriate part.

3Mechanical Measurement Lab Michael.Guinchard@cern.ch2009.09.07

Ground motion measurement• To measure the ground vibration, two geophones were placed close together on the

floor under YB0.• The measurements were provided while the cooling systems were off.

4Mechanical Measurement Lab Michael.Guinchard@cern.ch2009.09.07

1 10 100Hz

OOR

OOR

OOR

OOR

1000z

10a

100a

1000a

10f

100f

1p

10p

((m)²/Hz)GP_Ref (V)GP (V)

YB0 motion measurement

PSD of the signals Vertical direction

Geophones

1 10 100Hz

OOR

OOR

OOR

OOR

1000z

10a

100a

1000a

10f

100f

1p

10p

((m)²/Hz)GP_Ref (N/S)GP (N/S)

PSD of the signals Beam direction

Cooling system OFF

5Mechanical Measurement Lab Michael.Guinchard@cern.ch2009.09.07

HF structure motion measurementPSD of the signals Vertical direction

Geophones

PSD of the signals Beam direction100m 1 10 100Hz

OOR

OOR

OOR

OOR

1000z

10a

100a

1000a

10f

100f

1p

10p

((m)²/Hz)GP_Ref (V)GP (V)

100m 1 10 100Hz

OOR

OOR

OOR

OOR

1000z

10a

100a

1000a

10f

100f

1p

10p

((m)²/Hz)GP_Ref (N/S)GP (N/S)

Cooling system OFF

6Mechanical Measurement Lab Michael.Guinchard@cern.ch2009.09.07

Next Step

• Measurement of the motions of rotating shielding.

Geophones