Reports until 13:34, Tuesday 11 June 2013
H1 SEI
vincent.lhuillier@LIGO.ORG - posted 13:34, Tuesday 11 June 2013 (6698)
Current performance of the ISIs (vs OAT)

ETMY:
I have attached spectra of ETMY stage 2 motion in the Y direction measured during the single arm and a month ago while working on a new set of filters. Isolation was improved except around 1Hz (Blend filters are different) but stage 2 motion is close from the requirements. It is a better tradeoff.

The conditions of the measurements are specified below:

OAT:
- ISI
    - Damping
    - UGF 15Hz on all DOFs
    - Stage 1 Blend frequency at 100mHz with T240s in super sensors in X, Y and blend frequency at 750mHz in the other directions
    - Stage 2 Blend frequency at 250mHz in X, Y and blend frequency at 750mHz in the other directions

- HEPI
    - IPS-L4C blend frequency at 800mHz in all DOFs
    - UGF 10Hz on all DOFs
    - Sensor correction in X, Y and Z directions

2013 05 14 - Measurements starting at 1052610960 - 100s sample - 10 averages - 50% overlap
- ISI
    - Damping
    - UGF 40Hz on all DOFs of stage 1 and 32Hz in all DOFs of stage 2
    - Stage 1 Blend frequency at 250mHz with T240s in super sensors (all DOFs)
    - Stage 2 Blend frequency at 250mHz (all DOFs)
    - Sensor correction from ground (STS-2) to stage 1 in the X, Y and Z directions
    - Sensor correction from stage 1 (T240s) to stage 2 in the X, Y and Z directions

- HEPI
    - Pure position control - No blend
    - UGF 100mHz on all DOFs
    - No sensor correction


ITMY:
Damping and isolation filters installed on BSC1 (ITMY) are those installed during the OAT (minor tweaks were necessary since HEPI is locked). Isolation performance is similar to OAT. New set of filters will be designed when the HEPI will be unlocked.

Images attached to this report