Search found 1924 matches
- 05 Sep 2023, 18:18
- Forum: Ring Tracking
- Topic: Ring tracking with ciwggler element
- Replies: 6
- Views: 971
Re: Ring tracking with ciwggler element
Weijie, Thanks for posting this problem. It was interesting to analyze. (See attached for details.) I see two issues with the design. First, with only one rf cavity in the ring, the optics is badly distorted by the strong energy variation introduced by the wigglers; I addressed this by putting an rf...
- 29 Aug 2023, 09:54
- Forum: General
- Topic: Read off the one-turn matrix from the result files?
- Replies: 1
- Views: 832
Re: Read off the one-turn matrix from the result files?
Gunn, There are two ways to get this. You can supply a filename for the final output in the run_setup command. You'll find the Rij values in parameters in that output file. This is convenient if you are varying something in the system and want to see how the matrix elements change as a function of t...
- 28 Aug 2023, 12:47
- Forum: Momentum Aperture
- Topic: Touschek lifetime calculation in presence of magnet errors in a ring
- Replies: 2
- Views: 469
Re: Touschek lifetime calculation in presence of magnet errors in a ring
Monika, You can use the sddssplit command to split the multi-page output files into many single-page files. Pairs of single-page files can then be fed to touschekLifetime. Once done running touschekLifetime, you can use sddscombine to combine the touschek lifetime results into a single file, which i...
- 28 Aug 2023, 12:43
- Forum: Ring Tracking
- Topic: simulation speed when there are multi-bunches and muti-IBS element
- Replies: 3
- Views: 594
Re: simulation speed when there are multi-bunches and muti-IBS element
Chao,
I wonder if in the case using bunch duplication you are setting the use_bunched_mode flag?
I would expect using N bunches to slow things down, because there is N times as much interprocess communication (assuming that IBS is a dominant factor in the simulation).
--Michael
I wonder if in the case using bunch duplication you are setting the use_bunched_mode flag?
I would expect using N bunches to slow things down, because there is N times as much interprocess communication (assuming that IBS is a dominant factor in the simulation).
--Michael
- 28 Aug 2023, 12:38
- Forum: Optimization and Matching
- Topic: Correctors of a transfer line
- Replies: 5
- Views: 921
Re: Correctors of a transfer line
You should use the corrected emittance in the optimization, but also be sure that you are controlling the residual dispersion. In general for off-axis injection into a ring, you should match the dispersion at the end of the last septum or kicker to zero. For on-axis injection, match the dispersion t...
- 28 Aug 2023, 12:36
- Forum: Ring Tracking
- Topic: Transient beam loading with passive Harmonic cavity
- Replies: 7
- Views: 4794
Re: Transient beam loading with passive Harmonic cavity
Pradeep,
I can't find that example. Can you post it?
--Michael
I can't find that example. Can you post it?
--Michael
- 28 Aug 2023, 12:19
- Forum: Linac Tracking
- Topic: Energy of different bunches in multi-bunch simulations
- Replies: 1
- Views: 574
Re: Energy of different bunches in multi-bunch simulations
Wei-Hou, Your file elegant.erl changes the DY values for the misalignment elements, so I would expect to see different vertical centroids for the bunches, which is in fact what's seen. There's nothing that introduces a significant variation in energy between the bunches, since dipole modes have a we...
- 16 Aug 2023, 13:01
- Forum: Linac Tracking
- Topic: Problems on running Pelegant with FTRFMODE
- Replies: 8
- Views: 806
Re: Problems on running Pelegant with FTRFMODE
Wei-Hou, There seems to be a bug in Pelegant that the bunch output from &bunched_beam gets 0 for the IDSlotsPerBunch parameter. I'll look into it. Using a zero-length drift lattice to get output via &run_setup's output parameter is a good workaround. Also, there are scripts called generateBunch and ...
- 16 Aug 2023, 12:52
- Forum: Optimization and Matching
- Topic: Phase advance
- Replies: 1
- Views: 442
Re: Phase advance
In order for phase advances to be available, you have to include a &twiss_output command with output_at_each_step=1.
--Michael
--Michael
- 16 Aug 2023, 12:47
- Forum: Ring Tracking
- Topic: model of ring by several ilmatrix elements?
- Replies: 4
- Views: 661
Re: model of ring by several ilmatrix elements?
Chao, The IBS simulation method is summarized in https://accelconf.web.cern.ch/IPAC2015/papers/mopma012.pdf The calculation of the emittance growth rates is based on Piwinski's method. This is computed in segments of the lattice and then applied to the particle distribution either as random scatteri...