Slice dispersion?
Posted: 05 Oct 2022, 09:58
Hi all,
I am looking into slice beam properties in a bunch compressor, so I have watch files along the lattice, some of which are at the centre of dipoles. I then slice these into longitudinal slices and use sddsanalyzebeam get the slice data for the bunch. In the output of these files there is horizontal dispersion etax and etaxp, which I have noticed are near constant along the centre of the bunch, but differ at the extreme head/tail slices of the bunch. From what I understand dispersion is a property of the lattice so it should be constant for each slice of the bunch.
I have attached a plot of Ct vs etax/etaxp and the file from which it was generated. The watch file was at the centre of a dipole.
How is etax/etaxp calculated in sddsanalyzebeam? Do you know why I have this result?
Thanks,
Adam
I am looking into slice beam properties in a bunch compressor, so I have watch files along the lattice, some of which are at the centre of dipoles. I then slice these into longitudinal slices and use sddsanalyzebeam get the slice data for the bunch. In the output of these files there is horizontal dispersion etax and etaxp, which I have noticed are near constant along the centre of the bunch, but differ at the extreme head/tail slices of the bunch. From what I understand dispersion is a property of the lattice so it should be constant for each slice of the bunch.
I have attached a plot of Ct vs etax/etaxp and the file from which it was generated. The watch file was at the centre of a dipole.
How is etax/etaxp calculated in sddsanalyzebeam? Do you know why I have this result?
Thanks,
Adam