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| ==== Report for week of 7/23 ==== * We finished adding cable clamps to the SR2 PI and SF. * We craned in the SR2 PI and installed the PI-SF rod. As expected, there was not quite enough load capacity for even a 2 Cu-segment SF. * We changed the CuBe spring on the SR2 PI from an F2 type to an F1 and got about an extra 2 kg, which is plenty for 2 Cu segments. * We moved the feedthroughs from the SR3 assembly frame to the SR3 tank. Mirapro then moved the assembly frame to the SRM area. Mirapro also moved the duct on the +Y side of the SR3 tank to give us access to that side. * We laid a new set of SR3 in-air cables running directly to the tank. (We will repurpose the original set for SRM.) * We reconnected the SR3 cables on both sides of the feedthroughs. We had to adjust the routing of the in-vacuum ones several times to stop them touching the tank, but we finally found a good solution. * With help from Ohishi-san we removed the First Contact and then unlocked the whole suspension by stages. We need to check the optic pitch and do a little more mechanical adjustment but we were able to take TFs and implement IM and GAS control filters. * Hirata-san and Fujii-kun received most of the SRM metal mass parts, did inventory and practiced some of the key steps in the assembly, especially inserting the Sol-Black coated parts without touching the delicate surfaces. * Mark did inventory of the BIO stuff for the WD and of the OL parts. |
==== Report for the week of 3/11 ==== * Fabian mostly helped Fujii-kun with the PRM. * Fabian monitored the SRM yaw drift. It gradually reversed but so far remained small. * Mark and Hirata-san debugged the BS: * We inspected the payload section and quickly found the problem: two RM EQ stops were touching, on the +L (-X,+Y) side at the top. This was probably because the stops had been adjusted with the IP unlocked and sitting a few mm to -L, whereas now we have the DCCTRL running and have been locking the IP at the LVDT zero. We drove the IP to L=+1.5 mm as a near-worst case, and backed off all the stops to give several mm of margin. Then we zeroed the IP pitch, roll and yaw with the picos. * We also opened the top of the BS and confirmed that the mechanical zero defined by the locking mechanism agreed with the LVDT zero. It was very close in L and T, but -728 µrad in Y, driven mostly by a -805 µm offset in H3. That much is probably not a dumb error but just a difference in technique among the three people using calipers to take data for the calibration. * We then prepared the BS for close-up: * We wiped and inspected the O-ring for the lid and replaced the lid. * We wiped all accessible surfaces in the lower half of the tank, rescued some dropped items (some PEEK tube and a small nut) and un-immobilized the LBB. * After all the above, the OL was a bit off-center but still on the QPD, and Nagano-san fairly quickly recovered the original alignment. * Terrence rebuilt the BS OL according to a new layout suggested by Simon, which avoids scrambling the pitch/yaw at the first steering mirror and greatly reduces the amount of diagonalization required. * Terrence noticed some anomalous cross coupling on the SR2 (but not the SR3) and we investigated. * We suspected it might be an odd position of the beam spot on the optic, so we took pictures through the camera and LED viewports of SR3, and opened the SR2 tank and used a white target, but the beam spots were in very similar positions - close to central vertically and about 3 cm to the left of center horizontally. * We suspected it might be something touching at the IRM (because the IM OSEM TFs were fine), so we checked using a stick mirror with the IP centered, but all EQ stops were well backed off. * We suspected it might be a ghost beam from the LEN/TILT beamsplitter (and one was clearly visible on the SR2 TILT QPD) so Terrence set up a beam block, which improved things slightly but not completely. * Finally Terrence discovered that the problem was mainly uneven sensitivities of the QPD quadrants, and devised a new calibration and diagonalization procedure which allowed for it. * Enzo and Terrence did a health check of the SRM and it was fine except for some apparent electrical noise around 240 Hz. They put in a notch filter to get rid of it for now. |
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| ==== Plan for week of 7/30 ==== * Mark, Enzo, Hirata-san, Fabian, Kozu-kun, Terrence, Panwei at Kamioka Mon-Fri. * Kozu-kun works at Mozumi Mon, Fri, and Thu afternoon. |
==== Plan for week of 3/18 ==== * Mark, Fabian, Terrence at Kamioka full week. * More OL stuff. * SRM controls and Guardian. * Reset SRM yaw and continue monitoring yaw drift. * Assist with pump down. * Work on Type B paper. * Tidy up. * Throw out foil and other garbage. * Gather and clean tools. * Gather and organize unused parts and fasteners. * Pull out unused cables in cable tray near SR3. * Return all unused cables to tent. * Tidy up cables in rear of SR2 rack. * |
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| ===== SR3 ===== * Finalize optic pitch, OSEM alignment. * Hook LBB, add ballast mass, set up temporary OL (horizontal beam, pitch/yaw only). * Identify/acquire items required for final OL (steering mirrors, second QPD, lens, collimator). |
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| ===== SR2 ===== * Fix issue with PI/SS/chain alignment. * Put magnets on SR damper ring (2 Cu segment pattern). * Remove PI-SF rod temporarily, install Cu segments and damper ring. * Do vertical height budget; choose optimum F0 keystone height. * Add estimated final ballast mass. * Do PI cable routing. * Adjust ballast/trim mass, with reserve for cables. ===== SRM ===== * Set up filter tuning area. * Tune F0 for SRM. * Add LBB blade units, cable clamps etc. * Check PI coil connections, IP LVDT magnets. |
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| ==== 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)]] ==== Vacation Info ==== * Terrence: 8/24-26 f2f, then returns to Hong Kong. * Enzo: 9/14 JPS, 9/15 through 10/8 vacation in Chile. |
==== Vacation/Travel Info ==== * Enzo at JPS then final vacation, 3/13-29 * Terrence's last day, 3/29. |
Scraps of text for incorporation in the VIS Meeting Minutes
KAGRA/Subgroups/VIS/MeetingNAOJ
Type B (Mark)
Report for the week of 3/11
- Fabian mostly helped Fujii-kun with the PRM.
- Fabian monitored the SRM yaw drift. It gradually reversed but so far remained small.
- Mark and Hirata-san debugged the BS:
- We inspected the payload section and quickly found the problem: two RM EQ stops were touching, on the +L (-X,+Y) side at the top. This was probably because the stops had been adjusted with the IP unlocked and sitting a few mm to -L, whereas now we have the DCCTRL running and have been locking the IP at the LVDT zero. We drove the IP to L=+1.5 mm as a near-worst case, and backed off all the stops to give several mm of margin. Then we zeroed the IP pitch, roll and yaw with the picos.
- We also opened the top of the BS and confirmed that the mechanical zero defined by the locking mechanism agreed with the LVDT zero. It was very close in L and T, but -728 µrad in Y, driven mostly by a -805 µm offset in H3. That much is probably not a dumb error but just a difference in technique among the three people using calipers to take data for the calibration.
- We then prepared the BS for close-up:
- We wiped and inspected the O-ring for the lid and replaced the lid.
- We wiped all accessible surfaces in the lower half of the tank, rescued some dropped items (some PEEK tube and a small nut) and un-immobilized the LBB.
- After all the above, the OL was a bit off-center but still on the QPD, and Nagano-san fairly quickly recovered the original alignment.
- Terrence rebuilt the BS OL according to a new layout suggested by Simon, which avoids scrambling the pitch/yaw at the first steering mirror and greatly reduces the amount of diagonalization required.
- Terrence noticed some anomalous cross coupling on the SR2 (but not the SR3) and we investigated.
- We suspected it might be an odd position of the beam spot on the optic, so we took pictures through the camera and LED viewports of SR3, and opened the SR2 tank and used a white target, but the beam spots were in very similar positions - close to central vertically and about 3 cm to the left of center horizontally.
- We suspected it might be something touching at the IRM (because the IM OSEM TFs were fine), so we checked using a stick mirror with the IP centered, but all EQ stops were well backed off.
- We suspected it might be a ghost beam from the LEN/TILT beamsplitter (and one was clearly visible on the SR2 TILT QPD) so Terrence set up a beam block, which improved things slightly but not completely.
- Finally Terrence discovered that the problem was mainly uneven sensitivities of the QPD quadrants, and devised a new calibration and diagonalization procedure which allowed for it.
- Enzo and Terrence did a health check of the SRM and it was fine except for some apparent electrical noise around 240 Hz. They put in a notch filter to get rid of it for now.
Plan for week of 3/18
- Mark, Fabian, Terrence at Kamioka full week.
- More OL stuff.
- SRM controls and Guardian.
- Reset SRM yaw and continue monitoring yaw drift.
- Assist with pump down.
- Work on Type B paper.
- Tidy up.
- Throw out foil and other garbage.
- Gather and clean tools.
- Gather and organize unused parts and fasteners.
- Pull out unused cables in cable tray near SR3.
- Return all unused cables to tent.
- Tidy up cables in rear of SR2 rack.
Vacation/Travel Info
- Enzo at JPS then final vacation, 3/13-29
- Terrence's last day, 3/29.