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.

9:30 Demarrage machine

Fin installation Cerenkov + tests MRSV

Laser alignement Cerenkov arrive jusqu'a la camera a balayage

11:00 Demarrage machine

13:30 Arret machine. On a vu du Cerenkov dans la boite du milieu du couloir mais pas au dela. Rien sur la camera en salle laser.

9:10 warm up modulator

10:30: cycling of magnets

10:20 : scan charge phase

11:00 beam in the ring

Attempt to store at 500.02 MHz

Scan RF cavity phase at frequency 500,0117Mhz for different power in cavity

Optimization of dipole current to improve storage after ramping the cavity

Scan RF cavity frequency but results are difficult to interpret

Ccl: we kill the storage (50turns) for 50kV in the RF cavity

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.

The BLM detector boxes were installed in the ring. We connected 3 fibers and 2 scintillator detectors in th ring to be able to observe the beam losses.

Cabling, connection and checks of the BLM without the beam.

Machine start-up. Modulator was switched on at ~9h30.

Good storage.

Check of the injector and injection in the ring. Looking for the signal of the BLM withthe beam. Sucesfully; the signal was found with the fibers (see the screenshot attached).

Strange behaviour with the storage shot-by-shot: better and worse storage.  Nicolas, Jean-Noel and Mohamed is trying to check it. All the chain from the synchro generator to the RF cavity was checked and it is OK. To be investigated.

9h30 Start of the modulator and lasser (GATE is closed).

9h46 Data is taken as background.

Cavity is tuned to 500.38 MHz. Optimization of the energy and phase. 

RF cavity OFF. After previous tuning, the orbit is the same. Based on the simple calculation, to match to orbits, the RF frequency should be reduced by 60 khz.

New tuning of the cavity at 500.32 MHz.

After energy and phase optimization, the storage is obtained with a small dispersive orbit. Probably the real frequency is 500.33 MHz.

Test to decreaase the frequency to see at which frequency we can operate with the FPC if needed. Tuning of the cavity at 500.22 MHz. No storage obtained.

New test at 500.27 MHz. The beam storage is obtained with the dispersive orbit. Machine is depleted. At the moment the lowest frequency at which we can potentially operate is 500.27 MHz.

Coming back to the machine frequency of 500.33 MHz. Storage is obtained. Optimization to be done.

Data are taking at each configiration.

During the shift, we monitored the beam losses measured by 3 connected fibers. The turn-by-turn losses are clearly visible.

** Au vu de ce shift tres instructif d'aujourd'hui, pour demain:

1) Le sens le moins chronophage des scans table FPC sont:

Partir en Ty negatif, et aller vers Ty pos

Paritr en Tz positifs, et aler vers Tz neg

2) Avoir de visu les panneaux "charge" et "Stockage anneau" sur le meme ecran que l'intensite p-diode xline car aujourd'hui il n'y avait plus rien de stocke pendant un certain temps (inconnu) sans que ceux qui cherchent les X le sachent

3) Se mettre au point de fonctionnement anneau ~90% de stockage et non 30% comme aujourd'hui (facteur 3)

4) Se mettre et faire en sorte de rester a 100 pC, tout le temps, et pas autour de 50 voire moins comme c'etait le cas souvent aujourd'hui (facteur ~2)

** On a scane, sans succes :

Tz de 0 a 1.9 mm . La CFP perd un facteur 2 vers Tz = 1.5 mm, un facteur 10 vers Tz = 1.9 mm

Tz de 0 a ~ -3 mm CFP a delocke ensuite, on a decider de passer a Ty sans aller plus loin en Tz

Ty de 0 a 2.5 mm (maximum autorise)

Tz de 0 a -3.9 mm pour Ty = -2.5mm

Tous ces scans ont ete faits sans savoir en direct quelle etait la charge et le stockage, et donc ils sont a refaire dans les conditions 2), 3) et 4)

8h30 Start of the modumator, laser, magnet cycling

9h45 Beam is ON. Scan charge vs. RF phase.

Attribute Li/OP/OPT.01-ATT.01  is showing value 340mm, this is different from the nominal ones of 300-303. Charge to be remeasured at nominal ones.

Aujourd'hui on a detecte des X en mode desynchro (notre signal correspond a ~ 3.10**6 ph/sec)

*** Pour :

9h30 Intervention Maher pour dosimètre

10h00 Mise en chauffe modulateur et refroidissements

14h prises d'image laser selon églage du miroir M5. Le laser n'est pas bien aligné sur l'iris --> a reprendre

Recherche nouvelle position : phase focaliation max --> renregistrement image sur SST1 Qmax, position laser iris : 4.635mm, 1.736mm, au lieu de 4.957mm/2.358mm

Charge phase, phase chute de charge : 305 degrés. Réalignement du solenoide dans dosseir alignsoleno du jour (DTx= 0.977 DTz= 3.9836 DRx= 4.2364 DRz= -5.2545)

Energie = 4.95 MeV,

Mesure de dimension sur LISST1 en fonction du solenoide

On se place à 233 A, on passe la section sans steerer, charge avant 110 pC, après 60pC

A 200A, toute la charge est transmise.

A 180A, toute la charge est transmise pour LIH1=-0.2A, LIv1 +0.6A

position laser sans steerer : iris position : 6.942, 3.996mm, charge transmissise à 100%, atténuateur 327

'facteur 1.7'  atténuateur 309mm, mesure dimension en fonction du soleno sans steerer, image enregistrée sur TLSST1_180A_pos1 : 225A on perd de la charge

Mesure presque symétrique en sortie linac (no quad,)

Vérification de la phase section 112 au lieu de 103, avec soleno de 200A, avec l'aténuateur 1.84 dB, dipole à 161.2A

On ajuste l'atténuation : 1.92 dB, enregistrement image TLSST2_200A_pos1

test positions : 4.94/5.125, ingérable

on revient à 4.635mm, 1.736mm, réalignement soleno : DTx= 0.92647 DTz= 2.9043 DRx= 5.6536 DRz= -4.0738

on fait quelques quad_scan avec QP3, soleno 190A

Le derniers QP1=-2.2A, QP2=+2.6A,

Image enregistrée avec QP3=0 TLsst1_scan2_qp3_0, même chose pour Tlsst2 , Idip à 159.3A

TLSST1_scan2_qp123_0

image enregistrée

energie steerers 50MeV +/-5%

Arret

8h55 Démarrage modulateur et refroidissements

Intervention SPR terminé

Solenoide = 190A, pas de quadrupoles, LI/PS/STR.01-H.01 = -1A, LI/PS/STR.01-H.01 = 0.90A, position laser = hor 4.635mm ver 1.736mm, visualisation sur TLSST2 et les BPMs

Tests exploratoires de stabilité faisceau

Feedback utilisé par l'anneau : quand ecart > 500 um est mesuré pendant 50 coups, variation attténuateur de 10e-2

Dérives sur TL/SST2 ont plusieurs sources : position du laser, puissance incidente RF, et phase globale. Mesures systématiques en cours.

13h51mn16s modulateur est passé de 1089.3 à 1090.4V.

13h59 1090.1V 

14h18 arret feedback M4-M5

14h23 decrochage laser

14h37 mise en route feedback M4-M5

 14h55 reajustement de la phase sur TL/SST2 à phi = 257 pour forme faisceau

 14h56 1090.30V pour energie

14h57 1090.60 V

15h01 phi canon 258°

15h02 1090.2V - 1090V

15h08 1089.8V

15h09 phi canon 259°

15h11 phi canon 260°

15h12 1089.3 V 

Chute brutale apres coup avec délai

15h14 1090.4V

15h22 phi canon = 258°

15h27 1090.3V

15h30 phi canon = 259°

15h31 1089.5V

16h55 modulateur 1091.4V, phase 256

17h06 1090.9V

17h13 phase 257, 1090.2V

17h29 phase 254, 1091.4V

17h40 phase 255, 1091.2V

17h54 phase 257, 1090.4V

18h11 phase 255, 1091V

18h17 phase 256, 1090.2V

18h48 phase 255, 1090.8, chute à 18h40, quelqu'un a fermé quelque chose ?

18h56 phase 256, 

19h05 phase 254, 1091.4, 

19h16 phase 255

19h20 1090.7V

19h25 253 degrés

Arret

10h: Accès casemate

Ajout de deux cables près de TL/ICT.02, un jouant le role d'antenne et l'autre connecté à une résistance 50 Ohm. 

Cable n°36025 avec 50 Ohm sur WAC02 ch7

Cable n°36036 en antenne sur WAC02 ch5

Objectif: étude du bruit EM pour comprendre la fluctuation de charge détectée

11h : Mise en chauffe 

13h45 : Démarrage Faisceau 

13h50: Cyclage des aimants

14h: Scan charge/phase

14h30: Problème avec la mesure de charge: redémarrage des ds calc à 16h

15h: Transport jusque dans la TL

15h30: Prise de mesure des signaux ICT (avec les deux nouveaux canaux) pour étude de fluctuation de bruit => prise de mesure avec et sans faisceau

16h: Modulateur en HV

16h20: Modulateur en trigger => attenuateur section RF à 1.6dB

16h45: Injection dans l'anneau avec recette LI_TL_RI_test_20230627_16_46_07 sauvée sous le nom Beam stored (no RF, 150 turns)

16h49: Interlock cavité Pi Pr RF

17h05: Interlock modulateur status bit 12

*** Problème allumage modulateur ==> acquitement des défauts sur les MUX en physique (PC Mohamed HS)

*** Problème avec la cavité RF qui n'accroché pas avec le PID fréquence ==> redémarrage chassis PID

*** Réalignement tete de machine et injection "à l oeil" dans l'anneau

*** 21h: arret machine

Start of the modulator and laser at ~9h and hour later start the beam.

Working at 500.38 MHz to retrieve the previous state of the ring. Then switching to 500.33 MHz (assumed ring proper frequency).

- Optimization of the injection and ring (orbit, betatron/synchrotron oscyllations,  tune....)

- Load of the new optics with bigger MCF TDR_0.17_0.64_r56_0.4_sx_Dff41.2_DipMagnL.str : MCF=0.0231  chro=0/0. Optimization of the injector and the ring.

- Change the RF frequency to 500.25 MHz. Optimization of the injector nd the ring. The sufficient storage is obtained.

- Going to the 500.33 MHz and working on the orbit, energy and phase.

Observation: either energy or phase of the injector is not stable, it oscillates, so the amplitude of the synchrotron oscillations changes a lot (seen by the TbTX oscillation amplitude). Like this it is very difficult to find the proper energy and phase for the ring. We saved the trend (max TbTX). to be understand and worked out.

To be continued next week.

9h30 Start of the modulator and laser

Start of the beam. Problem with charge, the max charge at the end of the TL 60 pC. We can not increase it by the attenuator. To be understood.

Corrector ri-c2/ps/str.03-h.01 does not work => problem to control and tune the orbit. JNC will look at it.