|
Size: 3617
Comment:
|
Size: 2738
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 2: | Line 2: |
| Line 6: | Line 5: |
| ==== Report for week of 11/12 ==== | ==== Report for the week of 3/18 ==== |
| Line 8: | Line 7: |
| * Kozu-kun noticed the BS OL was out of range, and Fabian and Fujii-kun investigated. It turns out that the temperature has risen by over 2°C, so all the GAS filters have sagged and several stages are touching. Miyoki-san and Furuta-san are looking at what can be done. * We ordered three more geophone cables in the standard (non-flipped pinout) to save time during the December vent, where we will replace at least two of the preamps to fix issues and take the opportunity to put in non-flipped ones. |
* Terrence notice that one of the IP LVDTs was not working. We traced it to an unplugged cable, plugged it back in and screwed it together to prevent a recurrence. * Simon helped us rebuild the damaged LEN OL QPD stage and Terrence reinstalled it. We removed a C-clamp that we had been using to immobilize the breadboard because it interfered with the QPD stage, and replaced it with a more elegant solution using a dog clamp underneath. * We noticed that the BS IP had fallen over in +L at some time shortly before Nakano-san aligned the optic on 3/18. Terrence tried to recenter it but it was unstable. We decided to remove the tank lid one more time and remove some arc weights. The IP frequency had been 39 mHz the last time it was measurable, and we increased it to a much-safer 80 mHz by removing 9 kg. We believe we were able to recover Nakano-san's alignment fairly closely. * Terrence then recalibrated and diagonalized both the TILT and LEN OL. * SR2 * Terrence recalibrated the OL. * SR3 * Mark pulled out unused cables leading into the SR3 cleanbooth. |
| Line 11: | Line 16: |
| * We cabled all the SF/... through to the rack and checked that all items worked. * We did the vertical height survey and found that as with SR2 and SR3, the chain is longer than the CAD, this time by ≈7 mm, and again mostly between the SF and BF. We decided on a keystone height of 11.5 mm (5 mm higher than CAD), which can be achieved with 1 kg more on the SF and 1 kg in reserve for a yaw stepper mechanism. We reset the height of the yoke to give near-zero LVDT output for the new nominal height, and corrected the sensing and actuation signs, but still need to do the calibration. * The final SRM small glass mirror became available, so we had Hirose-san ship it to us so we can install it while the suspension is still on the assembly frame. Hirata-san ordered shims to make up the new recommended thickness of 1.4 mm and a micrometer to check the combination, which should arrive on Monday 11/26. * Enzo took calibration data for the last batch of geophones, for SRM. We had to borrow cables from SR2 because one cable was missing and another was miswired. And it turned out that one of the SR2 cables was defective as well. But if we can find two possibly borrowed by Okutomi-san and rewire one, we should have enough for SR2 and SRM. The geophones appear to be healthy and we will seal them next week. * We raised the PI clear of the assembly frame and unlocked and centered the IP. We calibrated the IP LVDTs, and reversed connections to get positive LVDT output for positive yaw. We borrowed a HPCD from SR3-IM-V for the SRM IP but haven't checked the actuation yet. * SR2 * While we were grabbing geophone cables from SR2, we added extra arc weights to get the IP frequency below 0.1 Hz. * Akutsu-san showed us how to install the OL transmitter support pillar, receiver shelf and viewports. We believe we have the parts to finish setting up the SR2 OL. ==== To-Do Lists, Schedule ==== * [[KAGRA/Subgroups/VIS/TypeB/ToDoBS]] * [[KAGRA/Subgroups/VIS/TypeB/ToDoSR]] * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=7779|JGW-L1807779 Type B Schedule (SR)]] |
* Terrence set up the SRM Guardian. * Etc/All * Mark did an audit of the OL whitening/dewhitening system and fixed a bunch of problems: the SRM chassis was the wrong type, with no actual whitening card; SR2 and SRM needed whitening filters turned on; BS LEN needed the dewhitening turned on; SR2, SR3 and SRM needed dewhitening filters installed and turned on; SRM needed more gain. * Terrence weeded out a minor error from his OL diagonalization scheme and got L, T and Y independent at the 1% level for SR2 and SRM. He will do SR3 next. * Fabian measured the gain resistor values and other settings of the LVDT drivers, in case a card or chassis fails and we have to approximate the original state without the chance to recalibrate from scratch. * Fabian monitored the pumpdown. |
| Line 26: | Line 23: |
| ==== Plan for week of 11/26 ==== * SRM * Clean tools and metal parts for final SRM glass mass. * Swap in final glass mass. * Adjust SF trim mass. * Check/adjust alignment of SS. * Calibrate IP LVDTs. * Add arc weights and geophones. * Improve centering/tuning of IP and SS alignment. * Disconnect cables at feedthroughs, lock suspension. * Crane into tank. * SR2 * Finish OL setup * TFs. * Control loops. |
==== Plan for week of 3/25 ==== * Mark, Fabian, Terrence at Kamioka Mon-Thu. * Assist with alignment. * Work on Type B paper. * Tidy up. * Throw out foil and other garbage. * Gather and clean tools. * Gather and organize unused parts and fasteners. * Return all unused cables to tent. * Tidy up cables in rear of SR2 rack. |
| Line 42: | Line 34: |
| ==== Plan for week of 12/3 ==== * f2f Meeting at NAOJ - no Kamioka work. ==== Plan for week of 12/10 ==== * Prepare for vent of BS. * BS work - see [[KAGRA/Subgroups/VIS/TypeB/ToDoBS]]. ==== Vacation/Event Info ==== * Hirata-san at Mitaka, Fri 11/30 (medical check for solvent use). * Enzo at Mitaka, Fri 11/30 (Mitaka day). |
==== Vacation/Travel Info ==== * Enzo's final vacation till 3/29. * Terrence's last day for now, 3/29. * Mark compensation day for 3/21: 3/29. * Type B going-away party for Terrence/Enzo, 3/29 in Tokyo. * Terrence's next visit from 4/18. * Fabian's vacation 4/26 to 5/10. * Mark's final day ≈6/28 (TBD). |
Scraps of text for incorporation in the VIS Meeting Minutes
KAGRA/Subgroups/VIS/MeetingNAOJ
Type B (Mark)
Report for the week of 3/18
- BS
- Terrence notice that one of the IP LVDTs was not working. We traced it to an unplugged cable, plugged it back in and screwed it together to prevent a recurrence.
- Simon helped us rebuild the damaged LEN OL QPD stage and Terrence reinstalled it. We removed a C-clamp that we had been using to immobilize the breadboard because it interfered with the QPD stage, and replaced it with a more elegant solution using a dog clamp underneath.
- We noticed that the BS IP had fallen over in +L at some time shortly before Nakano-san aligned the optic on 3/18. Terrence tried to recenter it but it was unstable. We decided to remove the tank lid one more time and remove some arc weights. The IP frequency had been 39 mHz the last time it was measurable, and we increased it to a much-safer 80 mHz by removing 9 kg. We believe we were able to recover Nakano-san's alignment fairly closely.
- Terrence then recalibrated and diagonalized both the TILT and LEN OL.
- SR2
- Terrence recalibrated the OL.
- SR3
- Mark pulled out unused cables leading into the SR3 cleanbooth.
- SRM
- Terrence set up the SRM Guardian.
- Etc/All
- Mark did an audit of the OL whitening/dewhitening system and fixed a bunch of problems: the SRM chassis was the wrong type, with no actual whitening card; SR2 and SRM needed whitening filters turned on; BS LEN needed the dewhitening turned on; SR2, SR3 and SRM needed dewhitening filters installed and turned on; SRM needed more gain.
- Terrence weeded out a minor error from his OL diagonalization scheme and got L, T and Y independent at the 1% level for SR2 and SRM. He will do SR3 next.
- Fabian measured the gain resistor values and other settings of the LVDT drivers, in case a card or chassis fails and we have to approximate the original state without the chance to recalibrate from scratch.
- Fabian monitored the pumpdown.
Plan for week of 3/25
- Mark, Fabian, Terrence at Kamioka Mon-Thu.
- Assist with alignment.
- Work on Type B paper.
- Tidy up.
- Throw out foil and other garbage.
- Gather and clean tools.
- Gather and organize unused parts and fasteners.
- Return all unused cables to tent.
- Tidy up cables in rear of SR2 rack.
Vacation/Travel Info
- Enzo's final vacation till 3/29.
- Terrence's last day for now, 3/29.
- Mark compensation day for 3/21: 3/29.
- Type B going-away party for Terrence/Enzo, 3/29 in Tokyo.
- Terrence's next visit from 4/18.
- Fabian's vacation 4/26 to 5/10.
- Mark's final day ≈6/28 (TBD).