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ID Date Author Categorydown Subject
  117   Wed Apr 6 22:29:55 2022 PatrickAcceleratorECooler voltages
ECooler voltages:

06.04:
22:30: 209676 V
00:14: 209647 V

07.04.:
00:46: 209647 V
04:06: 209648 V
  132   Thu Apr 7 08:43:19 2022 Danyal, Yuri, RaganAcceleratoragain no injection in ESR - ESR kicker problem
we had no injections in the ESR again 

it turned out that the injection kicker of the ESR has a problem 
  134   Thu Apr 7 09:58:55 2022 Ragan, Yuri, DanyalAcceleratorKicker problem solved
The kicker problem is solved and the beam is back in the ESR.
  135   Thu Apr 7 10:10:31 2022 Ragan, Yuri, DanyalAcceleratorProblem in UNILAC
The power supply of the UNILAC magnet is broken. The repair will take up to 6-7 hours.
  154   Fri Apr 8 09:13:38 2022 Ragan, DanyalAcceleratorNo beam
Cathode is being changed at the ion source. So no beam for the moment.

Sergey has been contacted to change from two ion bunches to a single ion bunch in the ESR.
  167   Fri Apr 8 15:42:20 2022 YuriAcceleratorSlits in the TE line
At around 15:00, The slits in the TE line were changed to :
TE4DS5HL -12 mm -> -20 mm
TE5DSAH 0 mm -> +15 mm
  173   Sat Apr 9 02:55:38 2022 CarstenAcceleratorKühlerausfall und Gründe dazu
Wir hatten heute Abend eine Kühlerausfall, der uns mehrere Stunden beschäftigt hat, weil gem. Anzeige in Device Control kein Netzteil mit „rot“ angezeigt/ausgefallen war (siehe unten).
Nach Rufbereitschaft Serge, dann Regina sowie Controls konnte zunächst gefunden werden, dass das Netzteil einer Clearingelektrode (GECEKD2D) keinen korrekten Wert hat. Problem mittels Operateur (Christoph ?) und Rufbereitschaft Contrls gelöst.
Kühler ist trotzdem jedes Mal ausgefallen, wenn man versucht hat, auch nur den geringsten Strom zu ziehen (mit Hilfe Telefonunterstüzung Regina).
Rufbereitschaft Jon.

Mit ihm haben wir dann herausgefunden, dass im Device-Control, bei Auswahl „Kühler“ UND wenn das Fenster nicht vollständig maximiert ist, die letzten drei Netzteile (ECEBG8T, ECEBG3D, ECEBG4D) nicht angezeigt werden und man auch den Scrollbalken nicht dorthin bewegen kann (ergo: nicht vorhanden sind…). Ist das Fenster von DC maximiert, tauche die Geräte wieder auf und ACH WUNDER ECEBG8T (Kollektor) ist rot, lässt sich einfach wieder zuschalten und auch der Rest wieder anschalten. Ein Fehler, den ich leicht hätte selber beheben können, wenn er denn nur angezeigt worden wäre.

Soll heißen: Man weiß zwar, das irgendwo ein Fehler ist, kriegt aber in diesem Modus das Gerät gar nicht angezeigt…
  175   Sat Apr 9 03:46:31 2022 CarstenAcceleratorSlits in TE line
Changed GTEDSAH Rechts to 10mm
  176   Sat Apr 9 03:57:10 2022 CarstenAcceleratorNew Cooler voltage after the crash of the cooler
After the restart of the cooler the Ohmlabs divider showed a voltage 16V lower than before. This could also be seen as a slight shift in the Schottky lines w.r.t to the bunching frequency and the marker. Corrected
the voltages at injection to DeltaU +3963V and in Sc 5/7 to + 3943V. Now perfect match with the old Schottky frequency.

Note: During the crash we found out that the device GECEKD2D did not show proper values. GECEKD2D is responsible for clearing the cooler of slow trapped ions ("clearing electrode").
Hence, the 16V may be due to partial filling of the space charge potential of te elctron beam.
  201   Sun Apr 10 15:29:37 2022 Carsten,SarperAcceleratorEcooler failed
Ecooler failed @15:23 Carsten is fixing it
Fixed @16:00
  205   Mon Apr 11 07:54:37 2022 Danyal, Alexandre, Kristian, SebastianAcceleratorJump in E-cooler voltage
We saw a jump in the E-cooler voltage at about 7:50. 
jump from 209619 to 209610 V 

At 7:56 it jumped back to 209619 V
seems stable now  
  206   Mon Apr 11 10:17:01 2022 DanyalAcceleratorInterlock - reset
10:17 
Wie heutemorgen in der Sitzung (morning briefing) vereinbart, 
führt Herr Florenkowski einen Interlock und danach einen Reset von E02MK durch. 
Das dauert nur ca. 15 min. 

nach dem interlock wurde der ESR "rot" 

Um 10:21 war das problem gelöst und der ESR war wieder "blau"
  209   Mon Apr 11 12:50:22 2022 KristianAcceleratorTh lifetime
We used the counter to measure the lifetime. During the 30 min scan time dropped only slowly. 

During a longer break, e.g., when the laser flash lamps are changed, one could take data over a longer time.
  216   Tue Apr 12 12:41:20 2022 Alexandre, SebastianAcceleratorno beam in SIS18
  225   Thu Apr 14 06:29:18 2022 Max, SebastianAcceleratorlesser ESR injection intensity
We now have less ESR injection intensity (see screenshot attached).

This can also be seen in the count rate after "UNILAC/SIS failures".
Before failure: ~7k-8k
Now: 3k

The stored particles in the SIS are only in the range between 1.4 and 1.7e9 
  226   Thu Apr 14 08:41:42 2022 CarstenAcceleratorLow intensity at the experiment after series of failures during the night
After the recovery from the failures during the night, we see much lower intensity at the experiment (measured with the particle detector count rate).
Instead of 8000-10000 cts we see only 3000-4000cts at comparable SIS intensities.
Also ESR cooler seems to be slightly unstable (wiggling lines) during injection. However, it is visually evident from the Schottky that the injected intensity already is much lower than yesterday evening.

All devices in ESR are (seem to run ) runnng properly, and also slit position (PN devices) are ok.

I am going to open the slits iin the SIS ESR transfer beamline. It would be useful to check for the SIS-ESR timing.
  227   Thu Apr 14 10:57:11 2022 CarstenAcceleratorMaintanence UNILAC / Op training
We had no beam since about 1000. Also, we are still trying to find out why we have such a low intensity in the expereimnt.
Presently, there is a planned maintenance in the UNILAC, beam is expected back in 25-30 mins.
The profile grid TE3 in the transfer beamline in front of the target will be used to check if the extracted SIS beam has changed compared to before the crash of the SIS.
All devices in the ESR seem to work normally including ramping of cooler current/voltage, dipole correction windings and sextupoles (all checked).
As we observed that coolng performace after injection is much worse Markus (Steck) suggested that we could try a longer manual cooling in machine 3 (pleae no cahnges in timimng) to see whether the SIS energy has changed (similar to about 1 week ago).
Cooler elctron current iis put back to 450ma (inejection / 40mA measurement).
  37   Tue Mar 29 12:47:26 2022 Ken Ueberholz Parameter setting for XUV and copper mirror detector
Some Default Settings for the XUV 
Detector. The copper 
mirror should always move fully in.

Possible positions: Between 0mm and 147mm. 
Background was 
very high for anything higher than 100mm 
in the last 
experiment. 50mm was optimal. This should 
be tested again 
with repaired and modified shields. 

Good default values for the XUV detector 
parameters have 
been proven before to be:

Cathode: -5V
Movable shield: 0V
Fixed shield: 0V
Main coil: 8A
Secondary coil: -2.4A

(negative values set in hardware, only 
positive software 
inputs are possible)
  47   Fri Apr 1 00:27:27 2022 Carsten Settings Particle Detectors /Tests with primary beam
All the beam settings will be given in a separate post.

We have 238U92+ centered in the ring with typically a few times 10⁷ ions.

SA_SZ (GE02DD2_G): Voltage 1200 V, Recomnied peak was scraped at about -50 mm, set the detector position to -25 mm 
We see very clean signals with amplitude 1,5V (Foto will follow). Threshhold: CFD "25" arb. units. count rate 8kHz - 10 kHz
Rise time 6ns (with all the cables).

NA_SZ (GE01DD2AG): No signals - cables in the ESR need to be checked

NI_SZ (GE01DD2IG): Can not be positioned, error from Control system: "Auftr. Stattus position set value out of range", Drive can however be positioned to the "Endlage innen" and "Endlage außen".

The Test above were with a DC beam. With a bunched beam we more rapidly loose the ions with the particle detector.
  50   Fri Apr 1 02:29:40 2022 Carsten ESR Cooler crashed
ESR cooler crashed. We could not restart the cooler. Since we had several other problems, we stop now.
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