new ion guide laser ion source installed. Pure target container without targetmaterial and without surface ion source.
Heat up to 580A for heat test of all components. Distance between target and repeller < 1mm
13:15 start heating TGHT, 1A per 30sec vacuum below 2E-7T
14:50 reached 200A at TGHT (1.5V readback same as frontpanel), vacuum now 2.9E-7T, proceed on to 400A
16:10 TGHT 350 A (setpoint, readback stopped at 269A) and 3.4V readback, sudden increase in vacuum from 4E-7T to 5.5E-7T and larger fluctuations, give it 10min
16:22 vacuum back to 4.4E-7T but some occasional vacuum spikes , proceed to 400A
17:00 at 400A / 4.13V, vacuum hit 2E-6T in between which delayed the heating, now decreasing, will goto 410A for half an hour and then 385A over night
Dec 12th
8:30 3.3E-7T Vac at 385A, goto 420A
8:50 7.5E-7T Vac at 420A, goto 450A
9:20 1.7E-6T Vac at 450A, goto 470A
10:00 1.5E-6T Vac at 470A / 4.5V
11:30 1.1E-6T at 520A/4.56V
Wednesday, December 12, 2012, 11:46 1.7E-6T at 550A/4.58V
Wednesday, December 12, 2012, 14:31
580A reached, Vacuum dropped from 1.8E-6T to 5.8E-7T in 2h
voltage read back is wrong as well Panel readings are 572A/6.99V (read back values in EPICS are 248A/ 4.6V)
Wednesday, December 12, 2012, 14:47 6.5E-7T at 592A/ 7.31V (Panel readings)
Wednesday, December 12, 2012, 15:01 there is no contact of the target to HV GND (especially the repeller), the target can still be biased to 5V
Wednesday, December 12, 2012, 19:48 5.9E-7Tvacuum is slowly going down now
Thursday, December 13, 2012, 00:23 5.5E-7T, start cooling down
Short summary on results of first heating teest with the Ion Guide Ion source:
The Ion source is still in good shape, nothing was effected by the heat. Just some deposition in the repellers and the exit electrode
The capton wires used for wiring the electrodes had some problem with heat and went black and got brittle - for the next test we will ad a Ta schield at the side of the source to prevent radiation inside the source. |