Ta tube was coated with TaC and wrapped with Ta heat-shields (3 layers)

Note:  placed tantalum foil heatshield on both sides of the copper heatshield assembly.

Desired temperature = 1800 C (expected TGHT ~430 A), TBHT will be set fixed at 230A (max).

Evap 2 was pumped down yesterday

Good vacuum = 3.00 e-03Torr

Bad vacuum = 5.00 e-02 Torr

Wednesday, November 03, 2021, 09:27

Start autoramp at 1A/min to 40A on both TGHT and TBHT

IGP1 initial:  5.3 e-07 Torr

Wednesday, November 03, 2021, 10:22

IGP1= 1.1 e-05 Torr

TGHT = 40 A, 0.5 V 

TBHT= 38.5 A, 0.41 V

Will keep while monitoring pressure at 0.5 A/min to 60A

Wednesday, November 03, 2021, 10:35

IGP1 pressure trending down

IGP1= 6.7 e-06 Torr 

Start ramp up to 60A at 0.5A/min

Wednesday, November 03, 2021, 11:24

IGP1 2.6 e-06 Torr and trending down

Start ramp up to 400A on TGHT and 230A on TBHT at 1A/min

Wednesday, November 03, 2021, 13:28 

 IGP1= 1.4e-05 Torr and trending down slowly.  Will increase ramp speed to 1.5A/min on both TGHT and TBHT to the same final current as before.

Wednesday, November 03, 2021, 15:56 

 IGP1= 2.1 e-05 Torr

TGHT = 400 A,  6.9 V

TBHT = 233 A, 4.1 V

 OMEGA = 1645 C

Will manually ramp up to 1800 C

Wednesday, November 03, 2021, 16:43 

 TGHT = 450 A, 7.9 V

TBHT = 233 A, 4.1 V

OMEGA = 1770 C

IGP1 increasing in Pressure.  Will leave for 4 hours at this current.

Wednesday, November 03, 2021, 20:48

IGP1= 1.0 e-05 Torr

TBHT= 233A, 4.1 V

TGHT = 450 A, 7.9 V

OMEGA = 1751 C

Starting ramp down at -2A/min on TGHT and -1A/min on TBHT