Start of the modulator at 9h45

11h30 Problem with water regulation. Probably falseread of GUN PT100. Hayg and Viktor is tryig to adjust manually the temperature of the chiller for RF gun. We stopped at the settings as attached.

12h20 Trying to set-up the beam

13h Problem with the Linac Trigger Laser delay, laser pulse is after the RF pulse end (see screenshot attached). We tried to ajust the delays but inthis case the dark current is very large ~80 pC, bigger then the actual beam charge. We came back to the initial settings.

Not clear what has been changed since yesterday. Need help from the injector team.

15h30 Problem is solved. It was the wrong value of the Largeur pulse HT. The nominal value is 5 us.

16h Setting the injector and try to inject in the ring

Optimization of the TL. It would be really good to have the

- Closed dispersion

- Beam centered in the QUADs (at least 2 last ones)

The TL was set, so that we can inject with almost no losses (see screenshot)

Was difficult to get several turns. It turnned out that the kicket timig was not correct. Not clear who chqnge it.

19h We reistablished the storage and try to optimize it.

8H15 demarrage chauffage Klystron et chiller

9h15 bunker ouvert (intervention société extérieure jusqu'à 9H30)

10H injection dans l'anneau avec recette 20221020-1420

14.20 come back to shift after seminar

-adjust TL 154.7 and Ring dipoles 156.56

- injection optimization  with RCDS  . 7parameters: dpi, Kicker, Septum, H,V steeres 3 and 4 of TL

- orbit correction

-data taking

ri-c2 /BPM 01-Lib04, need to be checked. Horizontal Orbit is always around 4 mm at that position.

Start of the machine by KD

11h20 The beam is in the ring

Optimization of the injection with the RCDS

Off-momentum injection from the injector

Based on the observation (attached here), it seems that there is a resonant excitation of the beam by the RF cavity. Difficult to scan with the dipole field.

=> The RF cavity should be checked and during the runs detuned.

=> Probably the priority to the RF cavity conditioning should be given to progress on the Ring comissioning

The BPM.04-LIB.03 (just before the FPC) gives a strange vertical orbit. This should be checked and further invetigated.

Test of the script to swotch off the machine by KD.

18h45 End of the shift

8h25 : Mise en chauffe (pression eau toujours OK)

 Intervention casemate :

- Sextupoles SP02 resseré

- Mesure au gaussmètre de DPI et DPE (la sonde est très abimée) : pour 2A on a 0.444 kG pour DPi et 0.424 kG pour DPE ce qui est égale au vu des incertitudes de mesures

Mise en chauffe modulateur et refroidissements

Résistivité : 3.53 MOhm et Pression eau : 3.7

9:40: Cyclage des aimants. Problemes habituels.

10:20 Beam ON

10:30 Scan charge phase

10:40 Chargement recette LI+TL 05/01 11h07

10:44 Chargement recette 11/01 17h31 LE non optimum

Phase section: 118 degrees

Faisceau bien centre sur TL/DG/SST.02 mais bouge beaucoup (cf images)

11:10 Reglage des fentes (15mm;25mm)

TL/DG/SST.03: Le faisceau bouge de 0.2 tache focale.

Tentative d 'injection dans la ligne d 'extraction: cela ne marche pas.

 Explication de Hayg: il faut aussi aller EL/PS/DPI qui n'etait pas dans la recette.

Le changement d' energie du faisecau pose probleme pour l'anneau: nous devons tout reajuster.

Tentative de chargement des recette anneau precedentes.

Nouvelle valeur pour RI-C1/PS/DP.01: 176.42A

13:25 RF section phase is now 111

Nouveau reglage des fentes: 10;34mmm

Apres midi: Tentative de stockage du faisceau sans succes...

Sur health check: le laser est passe en rouge.

17h57 Machine OFF

9h22 mise en chauffe

Pb site elog; autres sites web OK

Health check OK

10:00 Cyclage aimants 0K

10:59 Demarrage

12:00 Emittance scan

Transport beam through TL. Attenuator 1.6dB. Check that beam is similar in simulation and on the screens.

Beam image at each screen station for current transport (images to attach).

Transport till ring with nominal TL optics. All charge is transported.

Check dispersion to be nonzero for later compensation in dpi and septum.

TL QP5 changed to from 2.2 to 1.5. Impoved injection stability, this value is far from; the theoretical one. to be studied.

Optimisation of injection with RCDS.

Undure curernt conditions beam SPX = 2 and SpY = 1 @ ric1 / BPM.02 stable.

Libera 4 freezed. Restart did not helped to recover BPM05-Lib04; Others after restart working well. Sever restart with astor solved the problem.

Saved data to reconstruct orbit

17:00 Arrêt machine

9:15 Mise en chauffe

10:30 Ronde casemate

10:40 Start beam

RF laser vs section phase: 113

11:50 Le faisceau bouge de 2 taches focales sur TL/SST.03

12:10 Beam in the ring

13:00 Etude injection dans l 'anneau vs RF gun phase (cf plot). La phase de -52 degrees par rapport a la chute de charge semble bonne.

15:30 Etude de l'effet des fentes sur le pic a l'injection

Fente cote mur tue le pic a l'injection tout en laissant stocker vers 21mm

Fente cote anneau: tue l 'injection tout en laissant passer de la charge vers 14mm

Explication des graphes:

- ligne bleue = charge avant injection (bruit de fond)

- ligne orange = charge a l'injection

- ligne verte = charge apres 10 tours

- ligne rouge = charge apres 50 tours

- ligne magenta = charge apres 100 tours

17:00 Arret machine

8:50 Mise en chauffe

10h Starting the beam

Tuning of the TL

We started from the last Friday setting and the beam storage was not succefull.

Optimization of the storage. The RF freq was set to 500.424 MHz. RF voltage was 40-100 kV

After several optimizations, the good storage was obtained ~15h

The final RF freq 500.4099 MHz

The data was taken concerning the betatron oscillations. Should be analysed offline.

16h40 Shift finished.

~9h Start of the modulator

10h Tuning of the injector with KD

11h Try to inject in the ring. Only 1-2 turns after optimization. We tried previous injector settings, the situation is the same. We retuned the injector based on our previous experience with

Isolenoid = 234 ->220 A,

Laser phase = 289 -> 288 

LIL phase = 114 -> 110 (Att = 2.04 dB)

Settings are saved.

We found that the injection kicker timing was not good (-7.19 us). We put the previous setting -7.23 us

Problem to start RF Cavity. IP adress problem . A lot of Debug with Jean Noel. Working when not connected to THomx network. Philip is informed.

Machine stay in standby till tomorrow. 

8h30 : accès casemate controlé 

==> septum et kickers OFF et cavité RF OFF

==> problème cavité RF, mux 3 défaut de communication

==> impossible d'acquité les interlocks et redémarrer la cavité.

Morning restart of machine was easy for the same parameters from day before.

Problem with network was fixed by G. Philippon, it was due to the limited number of allowed ports in the new swith that was recently replaced.

Still we cannot start RF Cavity with Jean Noel. Ampli is working, but no communication of Consigne from Tango to LLRF hardware.

14.30 Cavity on, getting power.

Frequency 500.41->500.4094, and phase manual optimisation.

Power in cavity is changing from 60 kV to 80kV for  80kV setpoint.

Saving data for postprocess. Orbit correction.

Beam is stable and stored. Orbit is positive. energy is about 50.075MeV, ring dipoles 160A. Sextupoles on.

Extraction kicker started to extract just before injection.

10:00 Machine warm up

Magnets cycling

11:00 Start machine

Health check: problems with Red Pitaya and Vacuum

11:30 Scan charge phase: Charge too high (-118pC).

Laser attenuator was at 300mm => 295mm (-95pC)

RF section phase 112°

Attenuator 1.98dB

12:10 load recipe good_20230504_13_46_27

13:00 Intervention by Mohamed to start the cavity and record data points

16:42 Some storage at 500.3600MHz, Phase -30

17:15 Some storage at 500.3072MHz at Phase -29

17:20 Stop beam

9:33 Start warming up

9:45 Ducre is working on the plumbing but it shuld not affect operations

11:00 Intervention JNC pour problemes refroidissement

12:00 Start beam

12:30 Sweeping of frequencies on RF cavity in ring, found local maxima at:

-500.0441MHz

-500.0371MHz

-500.0186MHz

Ring optimisation at 500.0186MHz

Slits position: 10mm/31.5mm (no improvement) => removed

16:30 Beam stop (access by Ducre)

Modulator left on standby, laser Gated, Magnets ON

Summary of the search:

Recipe used: all_20230516_15_45_01 (LI+TL+RI, all_recipes)

Attached plot shows ring at f=500.0202MHz.

RF Cavity: 45kV, fundamental = 114276mm; Plunger 15.420mm.

We ramped the cavity up to 50kV. Going from 40kV to 50 kV decreases orbit quality => some parameters still to be optimised.

Effect seen for:

RI/PS/DP: +/- 1A kills the beam. Changes by 0.1A can improve the beam.

RF cavity phase: acceptable values are on a wide range (-20degrees => +40 degrees) still very wide. We should probably set the cavity around +10 degrees (center of the range) begore increasing the voltage

RF Frequency: we had more than 100 turns in a band of about 10kHz

No effect seeing for:

injection steerers (no change in stored beam orbit)

Suggestion:

Try to optimise the quadrupoles with current settings

Then optimise the RF cavity phase (check that manual changes and software changes have similar effects) and ramp slowly the voltage.

8:40 Start warming up, problem with PSS. It was restarted.

Problems to start and tune the RF cavity. A clear working procedure and reliable tuning should b defined to optimize the Ring comissioning progress.

Feedback for teh RF has the suspicious behavior. At motor position close to the nominal, the feedback ofsets the motor in the negative direction for 100k steps and then, comes back from negative to the requested position.

Sometimes the we lost the power in the RF cavity.

Start of the ring. RF power is ~10-30 kV and freq = 500.0202 MHz. We loaded the machine with the yesterday's setting.  Optimizattion of the storage and orbit/tune. No stored beam achived. Only a few tens of turns achieved.

We decided to ramp the RF frequency up to 100 kV. We could not tune the RF cqvity to our previous value 500.41. We found the plunger position only for 500.38 MHz, so we started to work on this frequency.

After optimization work, we have achieved the storage (see the figs attached) with a reasonable orbit.

By setting the sextupoles and optimizing the quadrupoles we achived to have the kind of clean storage, stable orbit. 

By injector optimization we reduced the betattron oscilation at the injection. From time to time, the RF section phase ans power should be corrected. The further orbit correction should be done.

The estimated tunes are  (~0.19, ~0.66).

Then, we started to go back to the nominam RF freauency 500.0202 MHz.

Tuning of the cavity. Power is 40 kV.

The difference in orbit is attached in the scrennshot. Then, after the optimization it was almost the same as this morning.

By calculating the FFT on the mixed signal with the scope (see screenshot), we found the following frequency 16.68*30 = 500.4 MHz.

Without RF power, it was not possible to measure the revolution frequency as the FFT had two-peak strucutes, which is complicated to interpratate/understand.

At the nominal frequency, no storage is achieved. We wants to measure the revolution frequency operating at 500.4 MHz. Start of the ramping the power at this frequency. Big problem to tune the RF cavity. We can not inject the power in the cavity.

=> The clear observation that the ring is more stable and the storage is possible with the frequency around 500.4 MHz. it means that the circumference normally is shorter by ~ 10 mm. Investigations arer ongoing.

In the morning, after the start-up pf the machine, scan phase-charge and small tuning it was possible to store the beam with the settings from previous day.

The storage was optimize withthe dipole current of 159.9 (best storage up to now). RF cqvity voltqge 20-100 kV.

Work on the orbit correction and BPM.

The the dipole current was tuned to the nominal current 159.3 A with sufficient storage. AT ~18h the RF cavity went down.

To be continued.

The main task for today is to measure the revolution frequency without RF cavity with the spectrum analyzer.

Start-up of the machine.

After setting the previous setting, the orbit was very different. We checked the injector, the beam also was different (based on the beam images) and based on the RF plots we suspected that the timing of the laser has changed.

We changed the delays, reworked the transport but then it needed much more time to optimize the injection. We made the reseanoble storage but decided  to come back to the original settings (to be consistent in oour studies). After that, not clear why, the orbit came back to the expected values (as it was on Friday).

Start of the spectrum analyzer. Machine is set to the seetings from last Friday. Beam in the ring is not very stable. We had a few kV in the RF cavity for a short period of time.

Measurements without the RF power and one measurement with a small power (a few kV). Plots are attached. The screenshot was done for the different oribt (dipole values).  Prelimenary conclusions: At nominal lattice (with some scaling), we can keep the beam in the ring in the energy range, which corresponds to the attenuation of the RF section of 1.97-2.14 dB (nominal is 2.03 dB). This coresponds to the revolution frequency range of x30 => 500.33 - 500.47 MHz.

At this frequency, the  mean orbit changes from about ~-3 to +3 mm.

Taking into acount this freauency/orbit change (70 kHz - ~3mm), it means that to come to the nominal RF frequency of 500.02 MHz, the mean value of the orbit in radial direction should be increased by about ~18 mm. The calculations show also that to reach teh nominal frequency due to the energy change ~5-7%, the larmor radius in dipoles should be increased by ~20 mm. All this is in agreement with what we have measured today.

=> All this estimations are certainly prelimenary.

Problem with RF cavity. Mohamed tried to solve it during the day, No storing power. We need the RF cavity to continue our studies.

Goal: understanding of teh beam natural revolution frequency. Study the effect of the dipoles.

We have started from the previous setting of the machine. Then we loaded the settings from last december and received better storage. RF cavity is OFF.

By working with the spectrum analyzer, we understood that previous measurements very probably were affected by the noise coming from the synthetizer, so the frequency measured corresponded to the synthetizer frequency.

At the same time, during the investigation, apart of the false peak given by the synthetizer frequency, there was some signals (difficult to interpratete) aroung 500.4 MHz. Investigations are ongoing.

In parallel, we are checking the BPM cabling convention by using the beam to be sure about the orbit readings.

Study of signal on scope:

Yellow: Losses monitor

Green: Sum of 4 electrodes RIC2/BPM.06

Blue: Long open cable (background pickup)

Screenshot from 2023-05-31 15-14-12.png Beam stored only for 1 turn not reaching

Screenshot from 2023-05-31 15-18-05.png: Green (BPM sum) cable disconnected

Screenshot from 2023-05-31 15-19-40.png: Green (BPM sum) cable reconnected

15:30 Checking BPM polarities

16:30 Created IHM to lock position on TL/DG/BPM.02 :  Diags/BPM/lock_position_tl_bpm_02.py

16:32 reload ring recipe

Screenshot from 2023-05-31 16-35-21.png : BPM signal with current in ring

Screenshot from 2023-05-31 16-49-49_I_159_3.png

Screenshot from 2023-05-31 16-51-58_I_161_90.png

Screenshot from 2023-05-31 16-56-12_I_157_90.png

Screenshot from 2023-05-31 17-02-41_I_159_90.png

Screenshot from 2023-05-31 17-03-15_I_161_90.png

Screenshot from 2023-05-31 17-10-02_I_157_90.png

Screenshot from 2023-05-31 17-11-53_I_161_90.png

Screenshot from 2023-05-31 17-13-59_I_157_90.png : We see the markers at the two node position. Delta X = 900ps

Screenshot from 2023-05-31 17-21-18_I_157_90.png : 3ns/div

When we change the dipole current we confirm that time to come back to the BPM change...

17h25: Machine stop

Bonjour,

Pouvez vous enregistrer les images de l'oscilloscope et le donnée brute à la place des screenshots. Il y a une option dans l'interface web pour enregistrer l'oscillogramme "proprement". De même pour les images, cela permet de faire des traitements à posteriori.

Merci.

Goal of the shift: Reestablish the good storage at 500.38 and then try to optimize the storage and orbit.

Start up of the machine.

RF cavity start up by Mohamed. Water leakage. Jean-Noel will fix tomorrow mornig. Mohamed also says that aparently the sinal from ring syntetizer is a bit noisy, to be checked with Nicolas.

problem with trigger of the TL BPM. Nicola fixed the problem. The cable was broken.

Load of the machine setting from 19/05. The injection in the ring is very unstable from shot to shot due to the tuning of the cavity. Coming to 100 kV @500.38 MHz synchronized with the ring. RF cavity works stable.

Beam on TL BPM.02 drifts a lot and very fast. See screenshots.

With the previous setting, we did not get the previous orbit. After small reoptimization we received the resonable storage. Still we should work on the orbit correction.

The main idea fo this week is to prepare the beam for the search of the first X-rays.

The main idea fo this week is to prepare the beam for the search of the first X-rays.

Start without RF cavity. Study of the orbit. Orbit correction. We menage to correct hor. and vert. orbit.

We put the RF cavity ON. A lot of interlocks during the day. Difficult to operate i this conditions.

Optimization of the storage.

Orbit corresponds to the disperive orbit. Should look at this. Maybe tune the frequency.

Very good storage was obtained. The Ring dipoles were changed to 160 A to minimize synchrotron oscillations and so improve storage. The orbit did not change.

Beam physics measurements to be started.

The main idea fo this week is to prepare the beam for the search of the first X-rays.

Start machine without RF cavity. During the day several reboot of the libera.02 (TL).

Study of the dispersion. Measurements of the horizontal dispersion by changing the injector energy (RF section attenuator).

Orbit correction.

Study of the tune. Tune response with the steptune. Tune measurements.

First try to measure the horizontal beta function at the quadrupoles.

RF Cavity ON. Good storage at 50 kV 500.38 MHz. Dispersive orbit. SHould understand how to reduce it. 

Different studies on the orbit.

Observations: position at the  TL/DG/BPM.02-LIB.02/SpX drifts a lot (a few mm range) all day long. We should correct it all the time to keep the beam orbit and storage.