On 27/11/2018:
Started tuning for 1.5MeV 6Li 1+. Set ladder to position #2 - Blank 10mm. Far S2 iris closed.
Run # 181127151653
- Run time: N/A
- Pulser ON, as before
- Target: Blank 10mm
- Beam: 1.5MeV 6Li 1+
Moved ladder to position #5 - natC III
Run # 181127152055
- Run time: N/A
- Pulser ON, as before
- Target: natC III
- Beam: 1.5MeV 6Li 1+
- DAQ Crashed
Restarted FAIR DAQ
Run # 181127153422
- Run time: N/A
- Pulser ON, as before
- Target: natC III
- Beam: 1.5MeV 6Li 1+
- Run stopped incorrectly by user
Run # 181127153506
- Run time: 489s
- Pulser ON, as before
- Target: natC III
- Beam: 1.5MeV 6Li 1+
Run # 181127155040
- Run time: 187s
- Pulser ON, as above
- Target: natC III
- Beam: 1.5MeV 6Li 1+
Moved ladder to position #3 - CH2 XVI
Run # 181127155607
- Run time: 908s
- Pulser ON, as above
- Target: CH2 XVI
- Beam: 1.5MeV 6Li 1+
- DT ~ 15%
Struggling to see beam in diode for all of these past runs.
Opened iris to use far S2 as diagnostic tool - beam is stopped in thick CH2 targets so detector is safe even at its small angular coverage (~5 - 15 degrees)
Run # 181127161508
- Run time: 14s
- Pulser ON, as before
- Target: CH2 XVI
- Beam: 1.5MeV 6Li 1+
No high rate seen
Run # 181127161656
- Run time: 194s
- Pulser ON, as before
- Target: CH2 XVI
- Beam: 1.5MeV 6Li 1+
- DT ~ 12%
Still struggling to see beam on diode
Found lemo cable used for diode timing between CFD and Logic OR has exposed cabling -> replaced lemo. See attached picture 1 for old lemo.
Run # 181127163416
- Run time: 106s
- Pulser ON, as before
- Target: CH2 XVI
- Beam: 1.5MeV 6Li 1+
Far iris opened
Run # 181127163848
- Run time: N/A
- Pulser ON, as before
- Target: CH2 XVI
- Beam: 1.5MeV 6Li 1+
Realised we were making a mistake when looking at the DAQ spectra. We were looking at ADC 2 (labelled as 3 on DAQ file browser) channel 16 (an S2 back strip) when we should have been looking at ADC 3 (labelled as 4 on DAQ browser) channel 16 for the diode
Closed iris, checked beam current. Using 10mm aperture FCC = 1pA.
Opened iris, moved ladder to position #3 - CH2 XVI
Run # 181127164749
- Run time: 556s
- Pulser ON as before
- Target: CH2 XVI
- Beam: 1.5MeV 6Li 1+
Ready to mount thin CH2 target.
At 16:55: Far S2 bias = -130.0V, leak I = 1.75uA. Diode bias = -70.1V, leak I = 0.00uA.
Pressures (mBar):
- TPU1 = 9,2e-7
- TPU2 = 3.4e-7
- TPD1 = 6.4e-7
- TPD2 = 6.8e-7
- CHUP = Sensor Off
- CHDW = No Sensor
Switched off detector biases, switched off preamps. Closed FCC valve. Closed line valve. Turbos off. T1600 backing and manual valves closed. Ecodry 1 and 2 off.
Vented chamber. Mounted thin target CH2 50 ~ 50mm from Far S2 - see attached picture 2.
Left 0.9um mylar in front of far S2.
Remounted far S2 and far preamp. With detectors on in air trigger rate ~ 9kHz.
19:00 Ecodry 1 and 2 on. Started opening manual valve.
19:15 pressures below 10 mBar, manual valve fully opened. T1600 backing valve opened. Turbos on.
19:25 Pressures (mBar):
- TPU1 = 3.2e-5
- TPU2 = 8.1e-6
- TPD1 = 6.0e-6
- TPD2 = 8.3e-6
- CHUP = Sensor Off
- CHDW = No Sensor
Far S2 biased to - 130.0V, leak I = 1.52uA. Diode biased to -70.1V, leak I = 0.00uA.
Closed iris, set ladder to position #2 - blank 10mm
See 1 -> 2 pA beam on FCC, opened iris ready for measurement. |