The DR setup was put into operation yesterday and first spectra recorded (see below).
Particle detector behind cooler ("SA_SZ") presently has voltage of 1350. The threshold at the CAEN CFD was set to 100 and changed to 150 today. There is a huge gap between noise and signal, however, today it seemed in DR that we had a burst of higher pulses.
Position is -45
Drifttube cooling first was tested with 200 mA.
The Cathode voltage of the cooler is therefore 905V higher than the actual cooling energy. The value measured with the precision HV probe is 205970 V
This is compensated by a -900V at the drifttube to decelerate the electrons.
A ramp is created: 208Bi01.dat that scans the CM energy range from 21 eV to 11 eV where the Bi79+ (1s2 2p_1/2 n=20) DR resonance is located. 1001 steps DEcm = 0.01 eV. Scanning direction high to low.
Times 40 ms measurement, 40 ms cooling ,
SubTrigs:
1 : 5000
2: 8200
3: 8400
4: 8600
Schottky files are recorded on NTCAP:
NTCAP 2025-05-10_19-09-35 (10 injections first 2 injections missing in NTCAP)
Bunched 200mA, run6.lmd, run7.lmd, run9.lmd (run8.lmd is empty).
First DR Peaks visible
Bunched 500 mA (new range) 24 to 4 eV stepwidth 0.02 eV high to low
NTCAP 2025-05-11_13-19-38, run10.lmd
run12.lmd (figure of DR peak attached, please note low channels are high energies)
not Bunched 500 mA, run11.lmd
run12.lmd (figure of DR peak attached, please note low channels are high energies)
run13.lmd is empty
19:10 changed the Go4 code
The measurements with bunched beam should be repeated. |