Hi,
I am looking at various chicane configurations and their effects on CSR emittance growth, and I ran into a configuration that shows a decrease in x-plane emittance which I am having a hard time to explain physically.
I have attached the chicane and input beam. I was wondering if you had any thoughts?
Thanks in advance!
Emittance Decrease After Bunch Compressor With CSR?
Moderators: cyao, michael_borland
Emittance Decrease After Bunch Compressor With CSR?
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Re: Emittance Decrease After Bunch Compressor With CSR?
I see a very small decrease in the emittance when I run your simulation. My explanation is that there are some correlations in your input beam that just happen to be cancelled by CSR effects. This could happen, for example, when the phase ellipse rotates in just the right way along the bunch.
One way to see that this might be the case is by reversing time and momentum offsets of the particles
then running again. The bunch is still compressed, but now the emittance increases slightly.
--Michael
One way to see that this might be the case is by reversing time and momentum offsets of the particles
Code: Select all
sddsprocess input.out input.rev -redefine=col,t,"t -1 *",units=s -process=p,ave,pAve -redefine=col,p,"pAve p pAve - -"
--Michael