On 24/11/2018:
At 8:35 the chamber pressures read (mBar):
- TPU1 = 2.2
- TPU2 = 2.2
- TPD1 = 2.2
- TPD2 = 2.0
- CHUP = Sensor Off
- CHDW = No Sensor
The chamber was vented and the CH2 XV target replaced with new ones.
See picture 1 for target ladder after dismounting - the beam spot from 7Li is clearly visible on CH2 XV.
The target ladder configuration is now:
| Target # |
Target |
| 1 |
Blank 3mm Aperture |
| 2 |
Blank 10mm Aperture |
| 3 |
CH2 XVI (840 +/- 40 ug/cm^2) |
| 4 |
CH2 XVIII (820 +/- 40 ug/cm^2) |
| 5 |
natC III (590 ug/cm^2) |
| 6 |
CH2 XX (880 +/- 40 ug/cm^2) |
| 7 |
CH2 XIX (890 +/- 40 ug/cm^2) |
See picture 2 for the new configuration.
The target ladder was remounted and at 9:15 the chamber pumped down. The far S2 still has the 12um mylar protective foil.
By 9:30 the pressures read (mBar):
- TPU1 = 4.6e-5
- TPU2 = 7.4e-6
- TPD1 = 6.8e-6
- TPD2 = 8.7e-6
- CHUP = Sensor Off
- CHDW = No Sensor
The Far S2 was biased to -130V, leak I = 1.38 uA. The diode biased to -70V, leak I = 0.00uA
A beam of 7Li 2+ 4.0MeV was focused onto the target position.
After focussing, FC4 = 260 pA, FCA = 250 pA. Both of these faraday cups are before the target chamber.
After focussing with the 10mm aperture, FCC = 195 pA. Focussing with the 3mm aperture, FCC = 190 pA. Faraday cup C (FCC) is after the target chamber.
A spectrum was collected for 7Li 4.0MeV
Run # 181124101041
- Run time: 717s
- Pulser ON, 25 Hz, as before
- Target: CH2 XVI
- Beam: 4.0 MeV 7Li 2+
- Trigger rate: 3285/s
- DT ~ 6%
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