Reports until 21:28, Monday 08 December 2014
H1 SYS
daniel.sigg@LIGO.ORG - posted 21:28, Monday 08 December 2014 - last comment - 11:59, Tuesday 09 December 2014(15500)
Commissioning calendar for next 2 weeks

We are in the process of preparing a cleaning of ETMY. Even so, it is not conclusive, ETMY has a clear problem as indicated by the green ring type absorption pattern which is thought to be due to first contact material left behind. At least 2 of the bright spots are extended and do not look like single point defects. A vent in EY is planned to start Monday next week. The opening of HAM1 has been delayed to next week as well to allow us to keep working with the Y-arm this week. Since we do not want to "bake" contaminants to the TMs, we decided to postpone any locking attempts and instead concentrate on a couple of task which previously had second priority.

Here is the list of commissioning task for the next 7-14 days:

Y-arm loss investigation:

  1. Make another wider scan on ETMY.
  2. Make a similar scan on ETMX.
  3. Try to understand the ITMY scan.
  4. Ring down measurements.
  5. Mode matching measurements.

Seismic:

  1. Investigate why the LHO performance is still lagging behind the LLO one.

Length team:

  1. Characterize PRMI power build-ups.
  2. RFAM measurements (including a EOM bias voltage).
  3. Measurement of the Schnupp asymmetry using the aux. laser on IOT2R.
  4. A good set of RFAM length measurements.
  5. Commission updated tidal compensation/length relief strategy.

Alignment team:

  1. DMRI WFS: add SRM alignment loops.
  2. Make EY green WFS work again.
  3. Add triggers to the auto-centering system, so it can be engaged automatically.
  4. Add a "bleed" feature to the auto-centering system, so it automatically resets when it looses the beam.
  5. Commission an arm alignment controls topology which can be used for initial alignment.
  6. Integrate green WFS into initial alignment.
  7. Revise initial alignment scheme.
  8. Investigate the temperature dependence of the TM orientation (T step in EX with cavity locked).

Miscellaneous:

  1. Fine tune Michelson contrast defect using ITMY TCS/CO2 laser.
  2. Set up the HWS to check the thermal lens.
  3. Investigate the long-term alignment stability of the mode cleaner ISS.
  4. Add an "ISS engaged" state to the IMC guardian.

RF:

  1. Revive the EOM driver.
  2. Make an assessment of RF cross talk into the IMC AOM.
  3. Investigate EMI radiation by the VCOs and the fixed frequency OCXO.
Comments related to this report
jeffrey.kissel@LIGO.ORG - 11:59, Tuesday 09 December 2014 (15511)
Link 

J. Kissel, H. Radkins, K. Venkateswara, J. Warner

To expand on Daniel's Seismic point, we *know* why LHO's seismic performance is lagging behind LLO. Here're our action items to fix it:
(1) Get sensor correction running on all DOFs of all chambers.
     (a) Assess functionality of STS-2s in the corner station, now that they've been iglooed.
     (b) Figure out why X&Y HAM2 / HAM3 sensor correction is only intermittently successful, get it implemented on all other HAMs
     (c) Use Rich's tilt-free IIR filter for Z on all HAMs instead of Hua filter.
     (d) Import LLO's X&Y BSC-ISI "0.43 [Hz]- only" sensor correction filter, see if it works for our seismic environment
     (e) Make sure CPS / IPS, low-frequency tilt-decoupling matrix elements (for HEPI and ISIs) are doing us good, if not fix them

(2) Figure out what's limiting each platform's motion at all frequencies using a NoiseBudget
     (a) Re-update Rich's BSC-ISI noisebudget model to be better organized, and to include getting live data and live filters like the full IFO's noise budget 
     (b) Make it produce plots that tell us what's limiting the BSC platform motion after sensor correction is turned on. We know that residual RY motion is limiting the performance, but we're hoping that the noise budget will help us reveal *why*.
     (c) Create / Update a HAM-ISI noise budget model in the same vein
     (d) Make it produce plots that tell us what's limiting HAM-ISI noise performance.