4 - Compare sweeps this morning and last night
5 - System only did 4 sweeps and stopped, because I forgot to replace "for i in range(0, 4)" with "while true"
6 - Can still take sweeps this morning, but don't have the full slowly changing set
7 - FIRST: Fixed dodgy connection on ADC/DAC box. The initial energy appears more stable. DAC = 4000 corresponds to 16.98V.
8 - Previously DAC = 4000 corresponds to 15-16V, varied if I moved the cable. Now it is stable.
10 - Current this morning ~1/3 of current yesterday
11 - Chamber and gun values from 2012-09-12 (yesterday) at 18:28
13 # Chamber Pressure = 8.55e-08
14 # Venault Voltage = 10.55
15 # Accelerating Voltage = 185.3
16 # Focus Voltage = -20.7
17 # Deflection Voltage = 6.76
18 # Initial Voltage = sweep
19 # Heating Current = 1.135
20 # Heating Voltage (across filament) = 1.165
21 # Heating Voltage (across power supply) = 1.52
23 - Electrode values from 2012-09-13 (today) at 10:06
25 # Chamber Pressure = 6.45e-08 ( - 2.10e-8 )
26 # Venault Voltage = 10.58 ( + 0.03 )
27 # Accelerating Voltage = 185.3 ( same )
28 # Focus Voltage = -20.7 ( same )
29 # Deflection Voltage = 6.76 ( same )
30 # Initial Voltage = sweep
31 # Heating Current = 1.135 ( same )
32 # Heating Voltage (across filament) = 1.155 ( - 0.010 )
33 # Heating Voltage (across power supply) = 1.498 ( - 0.03 )
35 - Very little change (except in chamber pressure)
37 - Comparison of plots; generate by running "compare.plt"
38 - Max current decreases over time. Decrease is significant in 2012-09-12 plots, small in 2012-09-13 plots.
39 - 2012-09-13 plots ~1/3 max level
40 - Level of increase moved slightly to left in 2012-09-13 plots.
41 - This is probably because the ground levels of DAC and power supply are closer now.
42 - Width of increase appears the same
43 - Plateau is flatter in 2012-09-13 plots
45 - Take a few more sweeps, then prepare Black Au.
46 - Hopefully will actually get it done this time.
48 - Had to go to tutorial at 11:00, then had lunch... then QFT Tutorial... didn't get back until 14:08
49 - Sweeps all appear similar, slight downward drift in maximum current
50 - I really hope the filament doesn't die.
53 - pressure monitored in 1408.pressure.dat every 5s
54 - Evaporate at 3.1A - entire ball melts after 18mins
56 - Decrease pressure; turn turbo pump back on. Pressure still in 1408.pressure.dat (pump turned on after t = ~2580s)
57 - Turn on filament (2980s) monitor sample current with max initial energy, wait for stabilise, then take TCS
59 - Note shift in work function from ~500 to ~800 counts
62 - Take TCS of Black Au
63 - Evaporate shiny Au on top
64 - See if TCS returns to original form
65 - Then vent chamber, turn off everything for electricians on Friday