PSL Checklist was OK Before 8 AM: - Balers were removing tumbleweeds up and down the X-arm. 9:23AM - 9:45AM Richard M in the PSL to install Lighthouse dust monitor 9:24AM - 9:56AM Kiwamu rotates the HWP in the PSL to dial down power to 100 mW 9:30AM - 9:45AM Gerardo in the LVEA to survey viewports at HAM2 11:11AM - 3:35PM Fil and crew in LVEA pulling cables to ISC racks. 1:14PM - 4:00PM SEI at HAM4 1:36PM - 3:00PM Corey at EY in TMS lab.
[Jeff K, Stefan B, + detchar] The bitmask defining the summary bit for the Input Mode Cleaner state-vector (ODC) has been trimmed to respond to only those bits recording the ASC WFS switch (bit 1), and the relative power indicators (bits 11 and 12). In this mode glitches in the WFS alignment will be recorded by the relevant bits 2-9 but won't affect the summary bit, and a low-power mode will still result in summary=GOOD. This was tested first at LLO and logged here. This hasn't been set in the safe.snap, but will be monitored and coordinated over the next few days.
The table extension for HAM 4 has been added.
Tour of visiting scientists
Searching for parts.
Work finished at 3:09 PM PT
Craning to shift the cable trays around HAM2 and HAM3.
This morning the masses were added to the Keel of the BSC at EY. All SEI serial numbers need to be double checked before cartridge install.
So instead of having the closed loop we implemented last Friday. We manually drove the offsets to get to the target position. Fringes seen and locking was possible (short stuff). I'll note the time as soon as I get back to the control room. As soon as, Ha! The transition started at 1655utc and finished around 1745utc.
HEPI is still floating and it still could be moving. Maybe we should put the HEPI on stops...
Cable pulling from H1 Electronics room to ISC-R1
Finished work at 3:35 PM PT
Written by Giles:
The attached document summarises the modal frequencies taken on the ETMy at LHO. The first tab provides a summary of the modes and measurement line width. The subsequent tabs in the spreadsheet provide the data and also plots of the data.
Giles, Betsy, Travis
Thanks all for posting this data. It should help the modeling a great deal.
Fibers stretched approximately 5.7 mm on both sides during the hanging process.
Due to the higher than expected cavity pole we are using the first boost stage (pole at 100 Hz and zero at 1 kHz) as part of the compensation. The second boost stage is too high in frequency. This morning we modified the second boost stage to be identical to the first one with a pole at 100 Hz and a zero at 1 kHz. This is serial number S1102630. In detail:
The removed parts are in a bag taped to the inside of the chassis.
Stefan, Yuta, Kiwamu
We are currently in a low power state for performing the PRM parking beam search.
Power decreased:
We decreased the IMC incident to approximately 100 mW by rotating the motorized half wave plate. We unlocked the interlock to allow us to rotate it while blocking the main laser pipe just in case. Currently the incident power is at 116 mW at the monitor channel, H1:PSL-PERISCOPE_A_DC_POWERMON. Then we locked the interlock back so that nobody can change the power.
Autolocker modified:
We then changed the ISC_IMC guardian script to adapt it to this lower power configuration. The threshold and in1 gain are increased by a factor of 10. Also all the LSC and ASC triggers are lowered by a factor of 10. We found that increasing the ASC common gain by a factor of 10 made the loops unstable. Therefore we set the common gain to be back at 1 as usual. So far it seems locking fine and stable enough to proceed with the parking beam mission.
Now we are back to 1W since we are done with the PRM parking search. We restored all the settings that we changed.
Turning down the output power to 100 mW.
Work finished at 9:56 AM PT.