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• VISMinutes20180713

Agenda/Minutes of the VIS Meeting on 2018/7/13

2018/7/13 13:30 - 15:10

Zoom Meeting

Participants: Mark, Sato, Takahashi, Aso, Terrence, Enzo, Hirata, Kozu, Shoda, Okutomi, Fujii, Ishizaki, Tanaka

Progress report

Schedule Chart

Type-A : (PDF/MPP)

Type-B: (PDF/MPP)

Type-A (Takahashi)

Past week report

[X-end]

• The keystone of F2 has gone to the upper side of bi-stable during the venting.
• Opened the cross tube and pulled down the filters, but the keystone of F2 (only) did not move.
• Opened the top chamber and set the height of F0 keystone to 4mm lower by the additional weight.
• Closed the cross tube and the top chamber to start evacuation.

[Y-front]

• Calibrated the LVDT in the F2.
• Measured the transfer function of F2 without additional load. The proper frequency was 0.63Hz
• Made more compression for the 6 blades. The proper frequency became 0.32Hz.
• Checked the range of FR. The FR can cover the full range of keystone height.
• Closed the cup and suspended the filter chain by the crane. The proper frequency changed to 0.40Hz (corresponding to the tuning frequency of 0.28Hz).
• Cabled around the F2. Checked the cable connections.
• Confirmed the signals of LVDT for the BF, the F3, and the F2 using the digital system.
• Lifted down the EQ stop into the corrugate tube. The end plate for F2 sit on the frame lock.
• Started the assembly of F1 stage. Assembled the end plate and embedded the FR onto the F1.
• Cabling in the F1.
• Started the preparation for swapping of IPs.

[X-front]

• Evaluated the ACCs.

Plan for coming weeks

• Setting of the F1.
• Transportation of the IPs from/to the first floor.

Type B (Mark)

Report for week of 7/9

• We cleaned up after the heavy rain. There was no significant damage but some cardboard boxes of parts got wet and the contents needed to be moved to other containers and the boxes discarded. Water collected on the SR2 crane slot cover and had to be vacuumed away before the cover could be opened. A new section of corrugated roof was installed to minimize the problem for the future.
• Enzo and team got all of the in-vacuum and in-air cables for the SF/... and PI properly routed and tested except (so far) for the geophones.

• Hirata-san and team finished tuning of the F0 for SR2 and moved the PI into the SR2 cleanbooth. It turns out to be about 8 kg weaker than for SR3, whereas the SR2 chain is only 3 kg lighter, so we will have to do some combination of decompression, removing Cu segments and using a stronger CuBe spring (e.g., a Type A F0 FR blade instead of the F2 one in SR3). We closed the floor in the SRM area for safety, but we will probably reopen it as soon as next week for the SRM F0 build.

• Hirata-san opened the SR3 tank, craned the LBB damper ring sandwich up to the top of the tank and suspended it.

• Enzo and team corrected a lot of flipped connections on the SR3 PI LVDTs (primary<->secondary on the horizontal, primary<->actuation on the F0).

• We added the arc weights and geophones and re-centered the IP. It seems stable and very soft, which is good.
• Fujii-kun worked on testing and repairing geophones and was able to give us a set of three for SR3.

Plan for week of 7/16

• Monday 7/16 is Sea Day.
• Mark, Hirata-san, Fabian, Kozu-kun, Terrence, Panwei(?) at Kamioka Tue-Fri.
• Enzo Wed-Fri.

Main Sequence

• Check/restore alignment of payload, especially optic pitch.
• Testing, TFs.
• Lock suspension.
• Crane into tank.
• Unlock suspension.
• Rearrange cables.
• Test.

F0/LBB Stuff

• Install correct IP in PI #2.
• Crane PI #2 to second floor.
• Rebuild top filter of PI #2 for SRM.

Plan for week of 7/23

• Mark, Enzo, Hirata-san, Fabian, Kozu-kun, Terrence, Panwei(?) at Kamioka Mon-Fri.

Main Sequence

• Start on suspending SF/... section of SR2.
• Try building SRM metal mass.

F0/LBB Stuff

• Continue preparation of PI #2 for SRM (F0 tuning, cable clamp installation, LBB blade installation).
• Get Mirapro to move AF from SR3 to SRM area.

To-Do Lists, Schedule

• KAGRA/Subgroups/VIS/TypeB/ToDoBS

• KAGRA/Subgroups/VIS/TypeB/ToDoSR

• 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.

Type-Bp (Shoda)

Past week report

Plan for coming weeks

OMMT & OSTM (Ohishi)

Past week report

Plan for coming weeks

VIS electronics (Tanaka)

Past week report

Plan for coming weeks

Other site works

• July 26 11:30 - 12:30: Monthly crane inspection
• Sept 10(Mon): Planned power outage

Safety

• Incidents:
• Foreseen risks
  • Type-A:
  • Type-B:

Discussion

X-End F2 problem

• We need to confirm if F2 is really fixed or not from transfer function measurements.
• Will ask Miyamoto-kun to work with Okutomi-kun on this.
• When the next time we open the X-End vacuum, we will try to lower F2 using the fishing rod.
• Fixing the F2 stage is a possible solution.

Type-A accelerometers/geophones

• According to Fujii-kun's measurement, the accelerometers with embedded pre-amplifier are also noisy.
• We should consider to use geophones also for ITM suspensions.
• Aso will check available money

SR2 TF optimal weight

• There will be up to 2kg of weight excess after removing 1 Cu segment.
• Stronger fishing rod blades will be delivered on July 27th. Probably too late.
• The best solution at this moment seems to be making the Cu segments thinner. (From 8mm to 6mm)
• Actual strategy will be determined after the SR2 PI is set on the assembly frame and the rest of the suspension chain is connected.

Missing cables for SRM

• Since the cabling scheme changed for SR suspensions, we need more in-vac cables.
• Enzo has a list of extra cables and working with Sato-san to order them

• We may not have enough cable material -> We will recycle broken or unused cables.

• We will buy more PTFE cable (100m) as spare.

Travel Plans

• Travel (Week of 7/16):
  • Takahashi: 17 - 20
  • Okutomi:
  • Sato: 17 - 19
  • Lucia 17 - 20
  • Ishizaki:
  • Mark: 17 - 20
  • Hirata: 17 - 20
  • Enzo: 18 - 20
  • Terrence: 17 - 20
  • Shoda:
  • Ohishi:
  • Fujii: 17 - 20
  • Tanioka:
  • Tanaka:
  • Kozu (ICRR): 17 - 20
  • Arai (ICRR):
• Travel (Week of 7/23):
  • Takahashi: 23 - 27
  • Okutomi:
  • Sato: 23 - 27
  • Lucia: 23 - 27
  • Ishizaki:
  • Mark: 23 - 27
  • Hirata: 23 - 27
  • Enzo: 23 - 27
  • Terrence: 23 - 27
  • Shoda:
  • Ohishi:
  • Fujii: 24 - 27
  • Tanioka:
  • Tanaka:
  • Kozu (ICRR): 23 - 27
  • Arai (ICRR):

Next meeting

On 2018/7/20(Fri)