R&D (Cryogenic)
SatoshiTanioka - 22:19, Friday 31 July 2020 (2133)
Q-mass operation check

What I did

Today I checked the operation of Q-mass which was installed on the cryostat.
It seems that Q-mass can measure some data as attached.
However, the pressure was not good enough to  measure reasonable data by Q-mass.
I tried to improve the vacuum level,  but could not reach below 0.3 Pa with Q-mass.

Notes

At first, there was a leakage around the tube between the cryostat and Q-mass which prohibited vacuum evacuation, though Q-mass operation requires less than 10-2 Pa.
Actually, it could not reach below 20 Pa.
This was due to the poor workability around Q-mass.
The bolts were not tightened well.
I somehow tightened them and the vacuum level was improved but not enough.

Next Step

I will try one more time to measure the residual gass by Q-mass.
After that, since indium sheet arrived, I will install temperature sensors and adjust the input optics and then start cooling down the cavity.

Images attached to this report
2133_20200801101309_20200731qmass.jpg