Scraps of text for incorporation in the VIS Meeting Minutes

KAGRA/Subgroups/VIS/MeetingNAOJ

Type B (Mark)

Report for week of 10/29

• SRM
  • Enzo realized that he could cover the next round of needed cables (all except geophones) with more cable soldering and did another batch. Because Yamamoto-san's lab was running low on isopropanol, Hirata-san washed them with ethanol at Mozumi.
  • Enzo worked out the optimum output resistance for the LPCDs to substitute for HPCDs with the horizontal IM OSEMs. The value was quite close to that already chosen for modified LPCDs by the cryogenic group, so we're going to standardize on 680 Ω. The modified LPCDs will have to be operated with the internal watchdog disabled for now because it was hard-wired to 2 mA.
  • Fabian finished adding the TM OSEM cables out to the rack and tested them.
  • We ran DC power and network to the second SRM stepper driver. We still need to get one more DC power cable to replace one we borrowed from SR3. We added the remaining steppers to the Python driver and MEDM screen.
  • We reconfigured the top of the assembly frame in preparation for the PI (removing crossbars and moving jacks down).
  • Hirata-san put the magnets on the SF damper and we hooked it to the PI, craned the PI into the assembly frame and joined it to the security structure.

  • We installed the F0-SF rod and flying saucer and suspended the SF/... section. We had plenty of spare load capacity, so we changed the CuBe spring to a weaker one and put 2.3 kg of ballast on the SF cap. This leaves 1.2 kg reserve for cables and an F0 yaw stepper mechanism.

  • We reduced the trim mass on the BF to compensate for the mass of the TM OSEM cables.
  • We measured all the bounce frequencies.
  • Hirata-san put magnets on the LBB damper magnet ring, put the pieces into the tank and assembled them into a sandwich ready for craning. He also did the fixed ring on the ceiling of the tank.
  • Fabian noticed that the DSub9 connectors on the PTFE cables are highly magnetic and need to be kept away from the magnets on the SF damper. This
• SR2
  • Hirata-san unclamped the LBB damper rings and suspended the LBB. It still needs ballast mass and is currently sitting high, with the blades at their upper stops.

To-Do Lists, Schedule

• KAGRA/Subgroups/VIS/TypeB/ToDoBS

• KAGRA/Subgroups/VIS/TypeB/ToDoSR

• JGW-L1807779 Type B Schedule (SR)

Plan for week of 11/11

• Mark, Enzo, Hirata-san and Fabian at Kamioka Mon-Fri.

SRM

• Main sequence
  • Cable/test IP LVDTs.
  • Cable/test IP FRs.
  • Unlock IP and center roughly.
  • Calibrate IP LVDTs.
  • Check/adjust alignment of SS.
  • Add arc weights and geophones (or extra mass equivalent to geophones).
  • Cable/test geophones.
  • Improve centering/tuning of IP and SS alignment.
• LBB
  • Crane LBB damper ring sandwich to top of lower section of tank.
  • Set tank jacks to nominal height.

Plan for week of 11/19

• Friday 11/23 is Labor Thanksgiving Day.
• Mark, Enzo and Fabian at Kamioka Mon-Thu.
• Hirata-san at Kamioka Tue-Thu (Mitaka on Mon for Engineering Promotion Office meeting).

SRM

• Unlock IP and center roughly.
• Calibrate IP LVDTs.
• Check/adjust alignment of SS.
• Add arc weights and geophones (or extra mass equivalent to geophones).
• Cable/test geophones.
• Improve centering/tuning of IP and SS alignment.
• Crane into tank.

Plan for week of 11/26

• Move SRM in-air cables over to tank.
• Unlock and align SRM.

Plan for week of 12/3

• f2f Meeting at NAOJ - no Kamioka work.

Vacation/Event Info

• Hirata-san at Mitaka, Mon 11/19 (Engineering Promotion Office meeting).