On 28/11/2018:

At 13:35: Far S2 bias = -130.0V, leak I = 1.55uA. Diode bias = -70.1V, leak I = 0.00uA.

Pressures (mBar):

• TPU1 = 3.3e-6
• TPU2 = 9,3e-7
• TPD1 = 1.2e-6
• TPD2 = 1.3e-6
• CHUP = Sensor Off
• CHDW = No Sensor

Switched off detectors, switched off pumps, closed manual and T1600 backing valves. Vented chamber.

Removed 0.9um mylar from far S2 - see attached picture 1 for mylar pre-removal. Removed far iris arm from downstream lid -> set iris to open position. Replaced far iris actuator with blank flange.

Remounted far S2 and far preamp - preamp still draws correct currents.

In air: Far S2 bias = -130.0V, leak I = 1.65uA. Diode bias = -70.1V, leak I = 0.01uA. Rate meter ~ 5500Hz.

Detectors bias off.

15:05 Ecodry 1 and 2 on, started opening manual valve.

15:20 Manual valve fully opened, T1600 backing valve opened, turbos on

15:30 Pressures (mBar):

• TPU1 = 2.2e-5
• TPU2 = 4.4e-6
• TPD1 = 4.0e-6
• TPD2 = 4.7e-6
• CHUP = Sensor Off
• CHDW = No Sensor

Far S2 biased to 130.0V, leak I = 1.59uA. Diode biased to -70.1V, leak I = 0.00uA. Ratemeter ~ 7000Hz.

Run numbers 181128153642, 181128161647, and 181128161758 are all alpha calibration runs. However DAQ connection was lost before the first run was started so the run time is not recorded for these.

Run # 181128162552

• Run time: 1408s
• Pulser ON, as before
• Alpha source
• S2 mylar: NONE
• DT ~ 20%
• See attached picture 2 for sample spectra from ADC2 Ch7 (ADC 3 in FAIR DAQ file browser)

16:45 Far S2 bias = -130.0V, leak I = 1.61uA. diode bias = -70.1V, leak I = 0.00uA.

Pressures (mBar):

• TPU1 = 2.8e-6
• TPU2 = 8.8e-7
• TPD1 = 1.2e-6
• TPD2 = 1.2e-6
• CHUP = Sensor Off
• CHDW = No Sensor

Switched off detectors, closed valves, turned off pumps, vented chamber.