NAOJ GW Elog Logbook 3.2
[Takahashi, Aritomi, Yuhang]
Today we opened the input chamber and checked the suspension of input mirror. Because of misunderstanding, we vented not only the input chamber, but also the PR/BS chambers.
Takahashi-san found that one magnet of the input mirror fell down. According to Takahashi-san, the magnet could touch the coil holder and the input mirror could be tilted because of it. In this situation, we tried to recover the tilt by picomotor and then the magnet could fall down. Takahashi-san will fix the magnet and close the input chamber next Monday.
After Takahashi-san adjusted the suspension, we could move the picomotor for input mirror and the green reflection overlaps with the injection now.
Finally, we started to evacuate the PR/BS chambers.
Takahashi-san glued the magnet to the input mirror and closed the input chamber. Since it takes one day for the glue to be fixed, we will evacuate the input chamber after tomorrow.
Pictures of gluing.
I started the evacuation of input chamber. First I used rotary pump until the pressure in the input chamber reaches below 0.1mbar. After I removed the rotary pump, I closed the small gate valve close to arm and opened the small gate valve close to the input chamber. I will wait until the pressure in the input chamber reaches the similar one in the BS chamber.
Before I opened the gate valves between input/BS and input/arm, the pressures in input, BS, arm was 1.3e-6 mbar, 9.9e-10 mbar, 3.1e-8 mbar, respectively.
First I opened the gate valve between input/BS. After 1 hour, the pressures in input and BS chambers became 5.5e-7 mbar and 1.9e-8 mbar, respectively.
Then I opened the small/large gate valves between input/arm. The pressures in input, arm became 5.4e-7 mbar,4.5e-7 mbar, respectively.