AIDA
GELINA
BRIKEN
nToF
CRIB
ISOLDE
CIRCE
nTOFCapture
DESPEC
DTAS
EDI_PSA
179Ta
CARME
StellarModelling
DCF
K40
CIRCE
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Entry time:
Sat Nov 24 16:39:22 2018
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<p>On 23/11/2018:</p> <p>Tuned beam for 4.0 MeV 7Li, charge state 2+</p> <p>Measured transmission of beam through FCC using 3 mm and 10 mm size collimators: 66 pA with 10 mm -> 60 pA with 3 mm -> 91% transmission</p> <p>FC4 = (330 - 263) pA = 127 pA</p> <p>Set target ladder to position 3 - CH2 target 15 (880 +/- 40 ug/cm^2)</p> <p>Start run</p> <ul> <li>Run # 181123130304</li> <li>Pulser: 70000 amplitude, x10 attenuation, 25Hz frequency (250Hz minimum fine setting), positive polarity</li> <li>Run time ~30 minutes</li> </ul> <p>Start run</p> <ul> <li>Run # 181123134943</li> <li>Pulser: as above</li> <li>Run time 588 seconds</li> </ul> <p>Moved to position #2 on target ladder, 10mm collimator. Increasing beam intensity -> have to refocus</p> <p>Moved ladder to position #1 (3mm collimator). Closed iris. Refocusing.</p> <p>Beam intensity after refocus: ~140pA with 10mm, ~90pA with 3mm. Trigger rate ~ 5500 counts/s</p> <p>Moved ladder to position #3: CH2 target 15</p> <p>Run # 181123142805</p> <ul> <li>Pulser: as above</li> <li>Run time: 1034</li> </ul> <p>We found high rates on ADC 1 -> swapped input cables between ADC 1 and ADC 2 (modules #2 and #3)</p> <p>Run # 181123144810</p> <ul> <li>Run time: 417</li> <li>Pulser: as above</li> </ul> <p>Set RAL thresholds to 20mV for first 8 modules</p> <p>Run # 181123150803</p> <ul> <li>Run time: 398</li> <li>Pulser: as above</li> </ul> <p>Did not help with ADC 1 counting less than ADC 2. Swapping ADC 1 with ADC 4.</p> <p>Run # 181123151711</p> <ul> <li>Run time: 324</li> <li>Pulser: as above</li> </ul> <p>Swapping back ADC 4 -> ADC 1. Found ECL cable between the MALU module corresponding to ADC 1 and OR not plugged in. Trigger rate now 44000. Re-optimising noise.</p> <p>RAL first 6 modules thresholds set to 30 mV. DT ~ 44%, high trigger rate.</p> <p>First 3 RAL thresholds set to 35 mV, next 3 RAL thresholds set to 20 mV. Preamp box lid removed.</p> <p>Run # 181123162236</p> <ul> <li>Run time: 348</li> <li>Pulser OFF</li> </ul> <p>Run # 181123163138</p> <ul> <li>Run time: 1561</li> <li>Pulser: ON, rate: 2.5 Hz, other settings unchanged</li> </ul> <p>Run # 181123165817</p> <ul> <li>Run time: 3731</li> <li>Pulser as previous run</li> </ul> <p>Run # 181123180118</p> <ul> <li>Run time: 1971</li> <li>Pulser ON, as before</li> </ul> <p>Run # 181123183556</p> <ul> <li>Run time: 1638</li> <li>Pulser ON, as before</li> </ul> <p>Checking beam intensity:</p> <ul> <li>Beam intensity = 197pA in FC4 at 18:34</li> <li>Beam intensity = 100 pA (91->105 pA) in FCC at 19:00</li> </ul> <p>Run # 181123191153</p> <ul> <li>Run time: 7029</li> <li>Pulser ON, as before</li> </ul> <p>Checking beam intensity:</p> <ul> <li>Beam current = 167 pA in FC4 at 21:00</li> <li>Beam current = 83 pA in FCC at 21:00</li> </ul> <p>Lowering RAL thresholds:</p> <ul> <li>RAL #1 and 2 thresholds set to 25mV</li> <li>RAL #3 threshold set to 20mV</li> <li>RAL #4, 5, and 6 thresholds unchanged at 20mV</li> </ul> <p>Now trigger rate ~ 5kHz, dead time ~ 8 - 10%</p> <p>Run # 181123212726</p> <ul> <li>Run time: 807</li> <li>Pulser ON, as before</li> <li>Target: CH2 XV</li> <li>RAL #3 threshold increased to 25mV during this run</li> </ul> <p>After previous run (# 181123212726) pulser frequency setting set to 25Hz, other settings unchanged</p>
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