2019/12/02 (Monday)

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Status	Warming up. All mixture in dump. LN2 trap 2 and LHe should be checked when warm. 1K Pot needle valve open, should be closed when warm before dropping cryostat. Some helium in cryostat vacuum jacket and IVC.
0940	MC(Cernox) = 289 K
0945	IVC = 7.4 mbar. Let 1 atm nitrogen into IVC.
0950	Close 1K Pot needle valve
0950	Close helium recovery valve for main bath
1000	Endstop1 to chassis resistance: 61 Ω. So after warming, the source holder is still in contact with the endstop. This is expected - the brass threaded rod will expand more than the copper plate, so if anything it should be pressing harder against the endstop.
1025	Cryostat vacuum jacket = 0.14 mbar. Start pumping out cryostat vacuum jacket, first with scroll then turbo.
1040	Turbo on cryostat vacuum jacket = 0.63 μbar. With turbo valved out, cryostat vacuum jacket = 46 μbar
1100	Turbo on cryostat vacuum jacket = 0.86 μbar. With turbo valved out, cryostat vacuum jacket = 34 μbar
1200	Turbo on cryostat vacuum jacket = 0.46 μbar. With turbo valved out, cryostat vacuum jacket = 25 μbar
1240	Turbo on cryostat vacuum jacket = 0.34 μbar. With turbo valved out, cryostat vacuum jacket = 22 μbar
1350	Turbo on cryostat vacuum jacket = 0.30 μbar. With turbo valved out, cryostat vacuum jacket = 16 μbar better than Sep 11, which was considered good enough to start Run 71.
1510	Turbo on cryostat vacuum jacket = 0.22 μbar. With turbo valved out, cryostat vacuum jacket = 12 μbar
1620	Turbo on cryostat vacuum jacket = 0.14 μbar. With turbo valved out, cryostat vacuum jacket = 10 μbar
1625	Stop pumping out cryostat vacuum jacket.
1635	Check contents of warm LN2 Trap 2: 20.8 mbar. Pump out with scroll pump.
1645	Check contents of warm LN2 Trap 1: 1.5 mbar. (This wasn't used during the run.) Pump out with scroll pump.
1650	Check contents of warm LHe Trap (by opening V1 and reading G1): 57 mbar. Wow, pretty high. Pump out with scroll pump.
1655	Lowered Dewar and erected clean tent.

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