20180125

http://klog.icrr.u-tokyo.ac.jp/osl/?r=4030

Today's activities

Workers: Akutsu, Simon, Miyo, Hasegawa

Brought small parts which was sent to Simon.
Brought several photosensor parts.
Brought a QPD board #032.
Discussed several points:
- Simon said that the suspended load was designed so that it should sit on the EQ stop just before cooling down, and the design was that it will be pulled up during the cooling due to shrinking of the parts and changing of the spring constant of the vertical blades. About this process, we were concerned that
  - In usual experience by VIS, once the suspended load will be released, the alignment would change, so Akutsu likes to have the load floated from the room temperature to cryogenic temperature.
  - Another concern is that the touching section might be frozen, and might not be lifted up while cooling down.
  - So we like to have larger gaps around the load in the vertical direction for the actual WABs.
  - And... what should we do in this test??
Located the WAB suspension to its nominal position in the first time!
- First we somehow input the WAB suspension in the cryostat. To do so, two persons were inside, two outside. Then outside two passed the WAB suspension to the inside two. On the optical table in the cryostat, I have already put a teflon sheet, on which the load was put down. During the process, due to narrow space in the chamber, it seemed difficult not to touch the workers body against the WAB's edges! Need to re-consider the installation procedure.
- Because the half of the base plate of the WAB suspension should be outside of the optical table when it should be in its nominal position, it seemed dangerous to leave the load without screwing the base plate to the optical table. So we put two misumi bars which are originally considered to be used as making a place to escape the WAB for installing the cryopayload. For this work, two folks were this side, and the other two opposite, and somehow moved the load. Due to about 50kg weight of the load, it was hard. Need to re-consider the procedure.
[Ongoing] Need cares of water springs from anchor bolts for oplev pylons.
[Ongoing] Need to confirm what are the scratch lines made by the measurement by the KEK team last week.

Tomorrow's plan

Try the saving mode (make WAB escaped).
Check the reproducibility of the alignment of the suspension among several modes.
Take the WAB suspension back to the table and detach some guard parts and check the balance, and attach them back;
Attach heater plates?
Try to connect bundy pins to the heaters??
Place bundy cables toward outside?
[Slightly done] Check tilt of the basement optical table in the IYC chamber.
Check heights of several points.
Wash the coil in ethanol at Univ. of Toyama...?
Pick up OptoSigma parts sent to Akutsu.
Take care of water spring??

Wanted!

Stages in the chamber
Chain block? to support the load in the chamber.
Cutters and scissors!!
A clock to know the time easily.
A fiber cleaner to connect oplev source parts; need to get back from Yend.
M6 screw set.