Scraps of text for incorporation in the VIS Meeting Minutes

KAGRA/Subgroups/VIS/MeetingNAOJ

Type B (Mark)

Report for week of 8/13

KAGRA was closed Mon/Tue 8/13-14.

SR3

• Enzo and team debugged an issue with height of the SR3 keystone coupling to yaw of the payload as measured by the OL. We suspect a ferromagnetic item on the SF damper, but we're not sure.

Report for week of 8/20

SR3

• Hatoya-san and Enzo gathered date for a study of yaw mode Q damping time as a study of damper ring height.

SR2

• We continued with cabling work.
• We configured the second pico driver and connected it.
• We assembled the LBB damper rings in the tank, craned them to near the top and hooked them. While the tank was open we also set the jacks below the mushroom that will support the suspension to nominal height.

SRM

• We reserved and configured two pico drivers.
• We checked the prism gluing and all the jigs came away successfully.
• Fabian assembled the RM.
• Hirata-san added ballast masses to the IM and we weighed it, as well as the RM and the optic in the mirror box.
• We suspended the optic and RM.

Report for week of 8/27

• We did an inventory of arc weights to see if we had enough for SRM and found that we had only enough for a basic allocation for all of type B (172 kg for BS and 103.2 kg per SR) and almost no spare for tuning. We did a quick study of the IP frequency as a function of the number of arc weights using SR3, to see how much more we might need. If SR3 is typical we would need about 27 kg extra per suspension.

SR3

• After the IP study, we left the SR3 with 6 10-mm arc weights and measured its frequency (with the digital system instead of a stopwatch).

SR2

• We finished routing the the in-vac

SRM

• We moved the SRM assembly frame into its final position, reset it to the initial configuration, double-checked the heights of the crossbars, and lowered the optical table by 3 mm (to give margin for the optic to rise during hanging, which we had kept forgetting to do). We cleaned it up with the airgun and wet-wipes. We installed the IM ring and IM.
• We assembled the SRM metal mass. Hirata-san made a jig from a plate with 4 screws which could safely hold the delicate front Sol-Black-coated ring upside down while the rest of the components were mounted on it.
• We moved the metal mass to the mirror box and added the prisms and magnet standoffs. We applied the EP30 on Friday morning, but probably won't be able to check the result until after Obon.

Plan for week of 8/13

• KAGRA closed Mon, Tue.
• Mark on vacation Mon-Thu, then Mitaka on Friday.
• Enzo, Fabian, Terrence, Panwei, Rikako at Kamioka Wed-Fri.
• Hirata-san on vacation all week.
• Fujii-kun to help part-time with crane work and/or the IP tuning.
• Diagonalization of new OL.
• TFs with new OL.
• Test of SF damper ring.
• Controls work.
• Tune SR3 IP.

Plan for week of 8/20

• Mark, Enzo, Hirata-san, Fabian, Kozu-kun, Terrence, Panwei at Kamioka Mon-Fri.
• Enzo, Hirata-san, Fabian, Kozu-kun, Terrence, Panwei at Kamioka Mon-Thu, then f2f.
• Kozu-kun works at Mozumi Mon.

SR3

• Hook LBB, add ballast mass.
• Tune IP.

SR2

• Adjust ballast/trim mass, with reserve for yaw stepper.
• Cable/test PI items (LVDTs, steppers, geophones).
• Set damper height.
• Add arc weights, adjust IP.
• Stage LBB damper rings in tank.

SRM

• Check gluing result - redo if necessary.
• Assemble RM.
• Add IM ballast masses (we forgot this before).
• Get parts from AOL and set up new pitch-setting OL.
• Hang metal mass.
• Hang RM.

To-Do Lists, Schedule

• KAGRA/Subgroups/VIS/TypeB/ToDoBS

• KAGRA/Subgroups/VIS/TypeB/ToDoSR

• JGW-L1807779 Type B Schedule (SR)

Vacation Info

• Mark: 8/13-16.
• Hirata-san: 8/13-17
• Terrence: 8/24-26 f2f, then returns to Hong Kong.
• Enzo: 9/14 JPS, 9/15 through 10/8 vacation in Chile.