Minutes from Beamdynamics meeting

Time: 16:00 2 Feb 2005
Place: 6/2-002
Participants: T. Asaka, H. Braun, R. Corsini, P. Eliasson, G. Geschonke, M. Korostelev, D. Schulte, F. Tecker, P. Urschuetz, E. Wilson

Roberto had a presentation on the status of CTF3.

CTF3 BDYN Issues (CTF3 BDYN Issues.ppt 1.27Mb)

Below is a resumé of what was said:

Transverse beam dynamics

The matching is problematic and Peter will study this with Parmela.

Daniel had designed and simulated this part. The wakefields should cause no problems. Ronen has developed a steering procedure based on Placet that works; Peter will continue to use this. The agreement of the modelling and the measured response of the machine needs to be improved. The correctors could be calibrated using a low current beam.

Stretcher and TL1
The emittance growth has been studied with MAD and the results seem to agree with Catherinas Elegant-simulations. Hans wondered which code is the best for simulation of CSR-effects. Daniel and Roberto thought that Elegant is good enough for now. Maybe in 1-2 years Traffik4 could be used. It may be possible to extend Placet or MAD.

Delay loop and combiner ring
This part has been simulated with Placet and at INFN with another code. Daniel thought that the studies of the deflector wake fields are not complete. Roberto pointed out that Davide Alesini has done some simulations similar to what Daniel wanted.

Longitudinal beam dynamics

Injector/1st chicane
Peter is performing some simulations to study parasitic bunches and to optimise the injector.

Stretcher and TL1
To use a pulse compressor, the beam phase need to be switched. Hence the beam is accelerated at two different RF phases. It can only be compressed in one phase but it would be desirable to compress in both. Right now the compression is done by chopping. The problem would be solved if the RF phase could be quickly switched, which seems not possible. Daniel came up with an idea how to do this by modifying the RF amplitudes, which was said to be easier. It was proposed that Igor and Peter should study this new idea.

After the presentation Daniel said that it is important to make sure that all codes are running and can be integrated. Roberto wondered if Placet could be extended to be used for a complete simulation of CTF3. Daniel thought that it might be possible by implementing longitudinal calculations in Placet. This could be one of the first tasks for the new EUROTeV fellow. Roberto also mentioned that it would be very helpful with a code that can simulate both CSR and high-frequency impedance.

The codes that were mentioned as possible candidates for complete CTF3 simulations were:

Hans and Roberto proposed that the authors of Elegant and the other codes should be invited to a small workshop. Roberto will look into this. Daniel proposed that the first step towards integrated simulations should be to make all used codes compatible in the sense that they could pass on information to the next code needed for the complete simulation. He also pointed out that the format for the beam-files sent between the codes should be standardized.

Hans then asked if there is any code that has a model of the wiggler. He also informed that two experts from Novosibirsk, who will participate in the wiggler workshop in Frascati (end of Feburary), will visit CERN before.

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Maintained by: Peder Eliasson
Last updated: 8 Feb 2005