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| ==== Report for week of 9/17 ==== * Monday 9/17 was holiday. * We optimized the trim mass on the SF to get more balance torque with less total mass. We now have a reserve of 480 g for the yaw pico. * We set the SF damper gap to 6 mm. * We set the SR2 pitch with the optic lever, aligned the IRM and set all the OSEMs to have good clearance and midrange output. * We locked the SR2 suspension (except for the SF) and craned it into the tank. * We moved the vacuum feedthroughs over to the tank. * With help from Ohishi-san, we removed the First Contact from SR2. * Mark did an audit of all the electronics boxes and updated the item list and S-number file cards on JGWDoc. * Mark did an inventory of some thin arc weights and finalized the number to order (8*38 mm + 9*10 mm). * Panwei copied control filters over from the SR3. ==== Plan for week of 9/24 ==== * Monday 9/17 is holiday (Respect for the Aged Day). * Enzo on vacation. * Mark, Hirata-san, Fabian, Panwei at Kamioka Tue-Fri. ===== SR2 ===== * Remove First Contact. * Move SR2 in-air cables. * Unlock and realign suspension. ===== SRM ===== * Set pitch of SRM and RM, tighten clamps, remove winch system. * Weigh IM/... section. * Build up SS to BF level. * Add BF. |
==== Report for the week of 3/11 ==== * Fabian mostly helped Fujii-kun with the PRM. * 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 9/24 ==== * Monday 9/24 is holiday (Autumn Equinox). * Mark, Hirata-san, Fabian, Panwei at Kamioka Tue-Fri. * Suspend IM and tweak height/balance. ===== SRM ===== * Cable/test BF. * Install IRM. * Install/cable/test IM OSEMs. |
==== Plan for week of 3/11 ==== * Mark at Kamioka full week. * Enzo at Kamioka Mon, Tue, then JPS. * Hirata-san at Kamioka from Monday lunchtime through Friday. * Fix BS. * Final test of stepper remote enable system (someone in cleanroom checks the lights go on/off). * Continue monitoring SRM yaw drift. * More mode Q measurements. * Work on Type B paper. |
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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)]] |
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| ==== Vacation Info ==== * Mark: 9/10-14 (job interview in US). * 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.
- 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 3/11
- Mark at Kamioka full week.
- Enzo at Kamioka Mon, Tue, then JPS.
- Hirata-san at Kamioka from Monday lunchtime through Friday.
- Fix BS.
- Final test of stepper remote enable system (someone in cleanroom checks the lights go on/off).
- Continue monitoring SRM yaw drift.
- More mode Q measurements.
- Work on Type B paper.
Vacation/Travel Info
- Enzo at JPS then final vacation, 3/13-29
- Terrence's last day, 3/29.