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ID Date Author Categorydown Subject
  223   Wed Apr 13 14:29:04 2022 Carsten, Rodolfo, Sarper, David, Pierre-Michel, Max, SebastianRunsAfternoon - morning shift runs 13.+14.04.
Changed the wavelength scan range from 321.62 - 321.10 nm to 321.12 - 320.60 nm after one scan.

TimeSIS-intensitycooler-HVLMD-DAQ2 file nr LMD-DAQ1 file nr scan range(nm)step width(nm)dwell time(s)particles countedcomments
14:28 1.9e9 209618 0254 7983 321.62 - 321.10 0.002 5s 7950
15:35 1.7e9 209613 0255 7984 321.12 - 320.60 0.002 5s 7100 Wavelength range has changed starting from this scan
16:21 1.8e9 209612 0256 7985 321.12 - 320.60 0.002 5s 6900
17:11 1.8e9 209619 0257 7986 321.12 - 320.60 0.002 5s 7950
17:57 2.0e9 209618 0258-0259 7987 321.12 - 320.60 0.002 5s 8900
18:48 2.1e9 209620 0260-0261 7988 321.12 - 320.60 0.002 5s 9260 After the scan was complete, we have realized that TCL 1064 computer is crashed.. fixed @ 20:05
20:07 2.1e9 209621 0262 7989 321.12 - 320.60 0.002 5s 7800
20:56 2.0e9 209620 0263 7990 321.12 - 320.60 0.002 5s 8190 After closing file, we replaced the dye from the laser.
22:10 0 209620 0264 7991 321.12 - 320.60 0.002 5s 0 No beam due to failures in Unilac and SIS. NTCAP stopped 01:44, restarted 02:15
02:20 1.5e9 209620 0265 7992 321.12 - 320.60 0.002 5s 0 Electron cooler problem during scan, bad file.
02:52 1.4e9 209624 0266-0267 7993 321.12 - 320.60 0.002 5s 3076 --> CU mirror in all time !!!
03:44 1.6e9 209625 0268-0269 7994 321.12 - 320.60 0.002 5s 5156 --> CU mirror in all time !!!
04:35 1.7e9 209624 0270-0271 7995 321.12 - 320.60 0.002 5s 3430 --> CU mirror in all time !!!
05:27 1.6e9 209621 0272-0273 7996 321.12 - 320.60 0.002 5s 3200 --> CU mirror in all time !!!
06:17 1.6e9 209621 0274-0275 7997 321.12 - 320.60 0.002 5s 3371 low particle count since 22:00, see ID:225, --> CU mirror in all time !!!
07:24 1.5e9 209622 0276-0277 7998 321.12 - 320.60 0.002 5s 3366 --> CU mirror in all time !!!
08:33 1.6e9 209621 0278-0279 7999 321.12 - 320.60 0.002 5s 2940 ecooler jumped to 209615 during measurement, --> CU mirror in all time !!!
09:26 1.5e9 209618 0280 8000 321.12 - 320.60 0.002 5s aborted, request of Carsten
09:46 1.6e9 209621 0283-285 8003 321.12 - 320.60 0.002 5s 2950 small ecooler current changes (300mA injection and 50mA @ measurement), fragments survive in schottky @ lower frequencies (see attached pic1 and pic2), it seems to be that the cooler does not work correctly in "phase 1" (pic 1), --> CU mirror in all time !!!
11:28 1.75e9 209624 0287 8005 321.12 - 320.60 0.002 5s ~1800 ESR cooler back to 450mA (injection), 40mA (measurement), additional manual waiting time of 15s in machine 3 (after injection before ramping); ABORT laserscan on Carstens request after ~1 loop; Sergey arrived and we get some time for ion beam adjustements, --> CU mirror in all time !!!
12:23 1.5e9 209623 0289-0290 8007 321.12 - 320.60 0.002 5s 8100 Cu mirror is again automated and intensity in ESR is back up ; @12:42 increase of the width of the ion beam (pic3) @12:43 again normal width, intensity dropped significantly over time afterwards
13:09 1.55e9 209622 0291-292 8008 321.12 - 320.60 0.002 5s 4852 beam killed @ loop 2 scan nbr 253 (8 steps missed)
14:00 1e9 209622 0293-0294 8009 321.12 - 320.60 0.002 5s 5509
14:48 9.5e8 209622 0295-0296 8010 321.12 - 320.60 0.002 5s 5477
15:47 1e9 209622 0297-298 8011 321.12 - 320.60 0.002 5s 6336
16:42 7e8 209619 0299 8012 321.12 - 320.60 0.002 5s 2424
17:45 9.9e8 209620 0300 8013 321.12 - 320.60 0.002 5s 5133
  230   Thu Apr 14 17:47:55 2022 Carsten, Rodolfo, Konstantin, SarperRunsAfternoon shift runs 14.04 changing the wavelength scan range
The new scan range is changed from 321.12 - 320.60 nm to 320.62 - 320.10 nm

TimeSIS-intensitycooler-HVLMD-DAQ2 file nr LMD-DAQ1 file nr scan range(nm)step width(nm)dwell time(s)particles countedcomments
18:36 9.5e8 209618 0301 8014 320.62 - 320.10 0.002 5s 6270
19:45 9.4e8 209615 0302 8015 320.62 - 320.10 0.002 5s 5400
20:44 8.4e8 209618 0303 8016 320.62 - 320.10 0.002 5s 4210
21:37 8.9e8 209616 0304 8017 320.62 - 320.10 0.002 5s 4550
  232   Thu Apr 14 22:44:40 2022 Patrick, Simon, Danyal, MaxRunsRuns night shift 14./15.04.
Runs of the night shift. The wavelength range is 320.62 - 320.10 nm.

TimeSIS-intensitycooler-HVLMD-DAQ2 file nr LMD-DAQ1 file nr scan range(nm)step width(nm)dwell time(s)particles countedcomments
22:38 9.5e8 209621 0305 8018 320.62 - 320.10 0.002 5s 5000 laser scan was started 1 min late
23:38 9.8e8 209622 0306 8019 320.62 - 320.10 0.002 5s 5550
00:32 1.0e9 209621 0307 8020 320.62 - 320.10 0.002 5s 4000 After ~4000 counted particles (second scan, 1:04 am) the e-cooler went off.
01:21 1.1e9 209622 0308 8021 320.62 - 320.10 0.002 5s 6700
02:12 1.2e9 209623 0309 8022 320.62 - 320.10 0.002 5s 6400
03:03 1.1e9 209624 0310 8023 320.62 - 320.10 0.002 5s 5500
03:55 1.3e9 209622 0311 8024 320.62 - 320.10 0.002 5s 7700
04:47 1.2e9 209622 0312 8025 320.62 - 320.10 0.002 5s 5300
05:36 1.2e9 209620 0313 8026 320.62 - 320.10 0.002 5s 6666
06:25 1.2e9 209619 0314 8027 320.62 - 320.10 0.002 5s 6500 change of shift crew (Danyal & Max)
07:16 1.2e9 209618 0315 8028 320.62 - 320.10 0.002 5s 5230
08:13 1.2e9 209620 0316 8029 320.62 - 320.10 0.002 5s 6600
09:04 1.1e9 209619 0317 8030 320.62 - 320.10 0.002 5s 6660
09:54 1.2e9 209619 0318 8031 320.62 - 320.10 0.002 5s 5950
10:49 1.1e9 209619 0319 8032 320.62 - 320.10 0.002 5s 6580
11:38 1.1e9 209617 0320 8033 320.62 - 320.10 0.002 5s 5380
  236   Sat Apr 16 04:19:05 2022 Patrick, Simon, Alex, SarperRunsRuns night + morning shifts 16.04.
Runs of the night shift 16.04. after changing the wavelength range. The new range is 320.12 - 319.859 nm. The step size was decreased from 0.002 nm to 0.001 nm.
The goal was to have the same number of scans as before (261), however, the scan range in the labview program could not be set accordingly. We decided to go with 262 scans after the first run.


TimeSIS-intensitycooler-HVLMD-DAQ2 file nr LMD-DAQ1 file nr scan range(nm)step width(nm)dwell time(s)particles countedcomments
04:24 1.28e9 209616 0338 8051 320.12 - 319.86 0.001 5s 6750 This run had only 260 scans
05:18 1.20e9 209615 0339 8052 320.12 - 319.859 0.001 5s 6300 First run with 262 scans
06:09 1.36e9 209615 0340 8053 320.12 - 319.859 0.001 5s 6910 laser scan started 2 min late at 650 counts
07:03 1.24e9 209615 0341 8054 320.12 - 319.859 0.001 5s 6330
07:59 1.23e9 209615 0342 8055 320.12 - 319.859 0.001 5s 5712
08:51 1.1e9 209615 0343 8056 320.12 - 319.859 0.001 5s 4380
09:44 1.28e9 209615 0344 8057 320.12 - 319.859 0.001 5s 5135
10:39 1.25e9 209615 0345 8058 320.12 - 319.859 0.001 5s 5860
11:30 1.2e9 209615 0346 8059 320.12 - 319.859 0.001 5s 6500
12:22 1.23e9 209618 0347 8060 322.41 - 322.00 0.002 5s 5200 Laser wavelength scan range is changed to 322.41 - 322.00 nm and increment to 0.002 nm.
13:04 1.2e9 209616 0348 8061 322.41 - 322.00 0.002 5s 4411
13:50 1.2e9 209616 0349-0351 8062-8063 322.41 - 322.00 0.002 5s 10651 last scan / 10 loops ~ 3 hours of scan -- Ecooler failed, realized at 16:05 we were on loop8, laser is turned off at 16:10
  1   Mon Jul 26 17:15:47 2021 RodolfoLaserQuanta Ray - Water leak
On Thursday afternoon (22.07.2021) a water connector has broken and water has been spilled in the laser head.
  2   Mon Jul 26 17:58:52 2021 RodolfoLaserWater Filters
The water filters (deioninzing and particle) have been replaced.
  4   Mon Aug 2 10:54:44 2021 RodolfoLaserQuanta Ray - Water leak in the power supply
After fixing the broken water connector in the laser head a new water leak appeared in the Quanta-Ray power supply.

We found the leak in the water pump flow line (arrow up). We took the water connectors appart, rebuilt the teflon seeling and put the water connectors back again.

Laser is back in operation.
  11   Thu Mar 3 13:50:45 2022 RodolfoLaserDye cell cracket
The "20 mm" dye cell used for the Oscillator and Pramplifier got damage. I supposed it was produced by the pump beam hitting on a very "old" dye solution (DCM / Ethanol, concentration 0,3 g/l). The solution in the dye reservoir was more 12 months old.
  13   Thu Mar 3 17:34:42 2022 RodolfoLaserPump Laser
We have issues with our Pump Laser (Spectra Physics - Quanta Ray Pro). After the service made on mid Dezember (2021) the laser does not get started. After contacting the service many times, the technicians think it can be an issue with the flashlamps.

- Flashlamps installed technician on 15.12.2021: FAILED.
- Flashlamps installed by Rodolfo on 21.01.2022: FAILED.
- Flashlamps installed by Rodolfo on 08.02.2022: WORK, however

the power is dropping extremelly fast. The measured power on 08.02.2022 was 21.6 W. On 01.03.2022 we measured 17,8 W (for 2.7 Millon shots). The flashlamps should stand 30 Millon shots without losing too much power.
  14   Thu Mar 3 21:39:21 2022 RodolfoLaserDye solution, DCM in Ethanol and DMSO
I have prepared a new dye solution of DCM in Ethanol and DMSO (1:1). The concentration of the "oscillator + preamplifier" is 0,3 g/l. The concentration of the "main amplifier" is 0,0375 g/l or "1/8" the concentration of the "oscillator".

Using 500 mJ pump energy (@ 532 nm) I get 120 mJ ouf of the dye laser (@ 640 nm). After the Frequency Conversion Unit I get 32 mJ (@ 320 nm).

Because the Biochemielabor will be not accessible during the first days of the Thorium beamtime, I have prepared enough reservoir for 7 days (assuming the laser system will run 24/7).
  33   Thu Mar 24 16:59:35 2022 RodolfoLaserPhotodiode signal SO
Fast Photodiode signal at the "SO-Bogen" (South-east arc).

- Average made over 250 samples.
- The photodiode is placed after two HR (high reflexion) mirrors.
  35   Fri Mar 25 14:31:24 2022 RodolfoLaserPhotodiode signal SO in the Messhütte
Measured at the Panel "Messhütte - Laserhütte", BNC "Fast PD / SO".

- Average over 256 samples
  36   Tue Mar 29 12:01:08 2022 RodolfoLaserLaser targets
I have installed two targets* (size: 2 inches) to monitor the position of the laser beam.

- The internet cameras can be accessed from any browser, but only inside the GSI-Campus network. Benutzername: admin. Kennwort: 1234

- Target SO (UV-Laser IN). Internet camera: atpdev005.gsi.de **
- Target NO (UV-Laser OUT). Internet camera: apdev17.gsi.de
- To move a specific target "in" or "out" the way just choose the target in the "target control box" and press the green bottom.


* The material of the target is Frosted Glass (Thorlabs: DG20-15ß00-H2-MD).
** The camera hang sometimes.
  38   Tue Mar 29 21:37:13 2022 RodolfoLaserPump Laser
The gold "reflectors and end plates" of our pump laser (Quanta-Ray PRO) have been exchanged by new ones.

- Output power after Oscillator and Amplifier (@ 1064 nm): 41 W.
- Output power after Second harmonic crystal (@ 532 nm): 18.2 W.
- Aditionally, we (Simon and I) have replaced the axial blowers in the power supply.

The picture shows the "old" gold reflectors.
  80   Sun Apr 3 13:05:08 2022 CarstenLaserDistance of Partilce detecotrs wr.t. to electron cooler
As of Yuris post in the elog the positions (Info from H. Weick):

The postion of the particle counter behind the cooler is 21.6 m behind the middle of the cooler.
This correspond to 21.6m /108,4m = 1 / 5.02 of a full revolution (please check the present revolution frequency, i.e. for 2MHz, i.e. 500ns we have the signal approx 100ns after the ion is in the middle of the cooler).
If the detecot Nord would be used for bunch timing (only planned if detctor south is defect) the distance  is half a ring + 21.4m, beind the center  of the cooler, i.e. (54.2m+21.6m)/108.4m ~ 0.7
  82   Sun Apr 3 18:41:11 2022 Konstantin and RodolfoLaserBeam Position Stabilization
We (Konstantin and I) have optimized the TEM "laser-beam position stabilization".

- I took some pictures (screenshots) about the current setting*.
- In order to be able to move the laser position faster we increase the P-Factor of both stages to 5 (maximum value).
- In "TriggerSignals_f_MRC_04-04-2022" the fast PD defines the origin (t = 0 s).
  101   Tue Apr 5 20:16:13 2022 RodolfoLaserDiscriminator for HF reference signal
For the laser trigger we need to generate a few ns NIM-puls from the HF reference signal. Therefore we (Wilfried, Konstantin and me) have changed the constant fraction descriminator (CFD) to generate this kind of pulse.

- We are using now the module N843 from CAEN, see picture below. With this we could now produce ~20 ns long pulse.
- This signal is also used as STOP trigger for the VUPROMs
  102   Tue Apr 5 20:58:53 2022 WilfriedLaserTrigger for Laser
Electronic for the timing of the laser puls optimized. The problem with the broad photodiode histograms is solved.
The photo of the oscilloscope picture shows in magenta the pulses from the (discriminated RF)/2, in yellow the pulses that are generated to open the Q-Switch. The latter are generated by the coincidence of the 30-Hz trigger (2 microsec long) to
allow for the Q-Switch to be fired. Within this period are usually 2 pulses from the RF and both generate a 100 ns long coincidence puls. The first one of those creates a 50 microsec long window (light blue) that is send to the Q-switch. The length
and the delay of this pulse can be changed. While the length is kept fixed, the delay can be changed in order to shift the arrival time of the laser pulse at the electron cooler to coincide with the ion bunch.
The problem of the wide photodiode histograms and the background was caused by a too large pulsewidth of the discriminated RF. The magenta pulses were about 100 ns long. Any pulse that arrives within a timespan between 99 and 0 ns before the 30-Hz
trigger of the Q-switch "allowance" will trigger a laser pulse immediately at the start of this trigger and therefore a jitter of up to 100 ns can occur. Therefore it is important that the CFD pulses are as short as possible, we set them to 20 ns
and the width of the photodiode histogram was just 3 bins wide (at the foot maybe 5 bins).

I (Rodolfo) just added the picture with the cabling configuration. The colors of cables match together with the colors show in the oscilloscope.
  118   Thu Apr 7 00:15:11 2022 PatrickLaserLaser timing adjusted
We have adjusted the laser timing using PMT-middle. Bunching freq. is 3.90362 MHz.

PD NO: 7.79
PD SO: 43.37
mean: 25.08

PMT middle: 25.02

Delta = 0.6 bins * 3.3 ns = 0.2 ns

New injection:
PMT middle: 25.48 / 101.91
ParDet south: 74.31 / 151.31

ParDet south - PMT middle (furthest / closest distance) = 161.1 ns / 91.1 ns
  120   Thu Apr 7 01:19:05 2022 PatrickLaserLaser scanning
We did some laser scans. The wavemeter shows spikes during scans. This may be just while the frequency changes. See picture.
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