31st March 2023: ammendment approved
Done:
M4.1.1 (M30 July 2022, DESY) Identify common beam physics interests, define necessary software developments
M4.1.2 (M30 July 2022, DESY) Definition of the work organisation for beam dynamics studies
M4.1.3 (M32 September 2022, ESRF) Define work organisation and contributors to the tasks identified in M4.1.1
M4.1.4 (M36 Jan 2023, DESY) Beam Diagnostics: Definition of the work organization for beam diagnostics studies
D4.1.1 (M38 March 2023, ESRF) Preliminary technical report with proof of principle validation on simplified test cases
M4.1.5 (M42 Jul 2023, ESRF) Beam Diagnostics: Selection of the shaker device. DONE IN THIS MEETING.
To do:
D4.1.2 (M48, January 2024, DESY) Final technical report with detailed beam dynamics studies and documentation for EBS and/or PETRA IV
D4.1.3 (M48, Januray 2024 DESY) Technical report on beam diagnostics studies with detailed documentation.
25th September 2023
Eurizon Task 4.1
participants:
SL Simone Liuzzo YES
LH Lina Hoummi NO
SW Simon White NO
LC Lee Carver NO
NC Nicola Carmignani YES
IA Ilya Agapov NO
JK Joachim Keil NO
TH Thorsten Hellert NO
BV Bianca Veglia NO
LM Lukas Malina NO
EM Elaf Musa NO
For diag meetings:
HS Holger Schlarb NO
GK Gero Kube YES
SJ Szymon Jablonski NO
SP Sven Pfeiffer YES
SM Sajjad Mirza YES
KS Kees Scheidt NO
BR Benoit Roche YES
EB Elena Buratin NO
FE Friederike Ewald YES
CC Christopher Cortes YES
Meeting for Diagnostics
presentation form PETRAIV S.P.
IPAC2024 paper on shaker simulations. OK!
presentation from G.Kube (PetraIV-TAC)
pinhole CD shape design by F.Ewald: smaller PSF
for PetraIV initially pinhole immaging, later (1-2 years after diffractometry)
does it make sense to make combined beamlines pinhole/diffractometer? Postponed to after commissioning with in air-pihole (as ESRF) 7.5m distance
2x 3PW separated by canting dipoles in the same straigth section.
Lead shielding as for ESRF-EBS
resolution for 13-10 um initially. Later 9-6 um.
detecting 10 pm at the limit of the system.
hard to separate electron and photon beam. in experimental hall all space is taken a part condition shown.
BR your beamline hutch will be a collaboration with BESSY. Old colleague changed work. This is why there is collaboration.
BR Should we do work with Gunther Reim? No, just hired one of the people of PETRA-IV.
FE Densimet better than W. Who did the machining? GK. done in house.
FE: could we ask to make some densimet pinhole (paying the price needed)
FE .24 is what was asked for?
GK aimed at 20.
FE. 10 are needed for EBS precisely
SP presentation again.
MBFB actuator for emittance control H and V. Added to later technical design.
system will be in high beta region in long straigth sections.
less kickers than initially (4 instead of 8) same deflection angle as APS-U
BR: striplines are H/V?
SP: the 4 striplines for H plane, 4 striplines for V plane
CC: presentation. investigating round beam operation for the SR. simulations blow up with noise.
GPU simulations using X-Suite, 10^5 particles, chroma ~8,~8
60nrad necessary for regulation to 20pm. available 250nrad.
BR: sharp structures in figure of page 8. comparable to damping time.
CC: cooling down of the beam while shaking.
BR could be interaction with the noise. it could cool-down the motion.
NC: temporal evolution of the emittance is unclear. How large is the shaking around betatron tune? Did you try with a larger bandwith?
CC: amplitude detuning is negligible in this conditions (small amplitudes). rms amplitude of signal can be correlated with increase of vertical emittance. Temporal distribution and jumps are still under-investigation.
NC: could be nice to see it is really stable. for example simulating 5000 turns.
GK: can this blow up be activated before damping the beam on the collimators?
CC: objective of this simulation was not the collimator protections.
SP: MILESTONE OK. MBFB is able to do the job with the available shakers.
interaction with FOFB still to be investigated.
SP: TAC suggests to simulate MBFB in full ring, and include emittance blow up.
SP: for M4.1.5 the MBFB system is going to be able to do the job.
BR: multibunch feedback is to damp what you want to create. it is a problem.
when MBFB is on, blow up is affected strongly.
SP: TAC asked to simulate this interaction.
BR: it means you need an unstable beam. One solution is to not send any noise and use the gain of the multibunch feedback. Emittance would not be stable as beam is not stable. On the contrary, at high chroma, beam will be stable. So, there is no need of MBFB in operation. The problem will be that during injection the MBFB will not damp them.
SP: this are studies that have to be done.
CC: would we be able to feed arbitrary signals to the shaker? signal with frequency modulation with a phase jump. Could it be sent.
SP: it will be likely possible. it is simply a request for firmware experts.
CC: what is the bandwidth of the shaker. SP: 250MHz. but could be improved with additional digital electronics.
SP: could not use the code sent by NC
NC: measurement of effect of emittance blow up as a function of chromaticity
at high chromaticity the contribution to horizontal emittance is 7pm from the shaker over
400pm set with the blow up. at low chroma this is much stronger.
for vertical emittance the apparent emittance contribution is below 1 pm over 120pm measured,
driven by the BPM noise.
MILESTONE 4.1.5 ACHIEVED.
send google document to fill.
deliverable (January 2024):
System at ESRF
Simulations for EBS and PETRAIV NC + CC
measurements for EBS
System foreseen for PETRAIV (including choice of shaker device)
emittance measurement system
shaker system
References
Next meeting in beginning of December to review status of simulations and status of deliverable writing.