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2023/04/26 (Wednesday)

Previous Day

  • Lab in-personnel: Zach
Status Run 78 Preparation. Tower Installation complete. IVC closed, turbo pumping overnight
1010 Turbo pump failed, looks like the IVC is back up to 1atm.
1040 Valve out turbo and restart it, Matt has confirmed that it has its own roughing pump
1043 Pump out IVC with scroll pump again
1052 Scroll on IVC = 0.16 mbar, valve out scroll pump and turn off, will let the IVC sit and see how much it goes up
1149 IVC stable at 2.2 mbar, seems reasonable. Pump down again with scroll pump
1157 Tried switching over to turbo, the pressure went down to ~40 ubar but after valving out the scroll pump it slowly started increasing. The turbo pump makes a slightly noticeable high pitch sound and reads the warning F097, is this the usual warning?
Isolate IVC for now
1223 Try pumping out just the pump manifold, starting with scroll pump and switching to turbo
1225 Turbo seems to be running fine, already down to 0.25 ubar
The problem is likely to be with the indium seals then
1557 Turbo valved out, IVC at 1.4 mbar. Start scroll pump
1603 After 3 minutes, pressure on the trubo gauge is < 1e-1 mbar, so switching to turbo , but keeping scroll still ON since turbo might not hold up because of the leak
1612 Turned off scroll pump, IVC at 1.9e-3 mbar
1616 When I open the line to the Leak detector, the turbo gauge starts to read higher and went up slowly to 4e-2 mbar. I close the valve to the leak detector and turned on the scroll pump to stablize the pressure. During this time, leak detector made a jump from 1e-12 to 4e-8 and back to 1e-12 mbar L/s

1627 I wanted to reattach the valve to the leak detector, in case it was leaky. After I removed it from the leak detector port (with the line valved out), in a minute of two, i hear the turbo making a hissing sound, the pressure was going up(even with the scroll ON), and I quickly valved it out. I switched off the turbo power, valved out scroll as well.
1632 Restarted turbo, close the line to the IVC
1654 Turbo on IVC (scroll valved out) = 1.2 ubar. Start leak detector, connect to IVC, valve out Turbo pump. LD at 1.3e-10 mbarL/s, (With Turbo)LD at 2.5e-9 mbar L/s, (Turbo valved out) LD settles around 1.1e-8 mbarL/s
1710 Pressure stable at 1.9e-2 mbar. Leak detector doesn't show any signal when I squirt He around the joints
1730 Turbo valved out, keep the video recording for overnight and see the change by morning

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