CEA Codes forum

Dear Didier,

I simulated the simplest transfer line and obtained strange result. For the beam illustrated in fig.1 it is obtained output phase spaces shown in fig.2. By comparing this two figures one finds that output beam phase length is equal to 2000 degrees vs 360 degrees at the start. It seems to me not physical result. What can it be? Regards,

Dear Vyacheslav,

To me it looks perfectly physical, but maybe a representation of the bunch on more than 360° hurts you, but that's only one way to represente it. If you prefer to have it on 360° use option like shown below.

Regards,

Didier

Dear Didier,

thanks a lot.

Please, clarify is it still a single bunch that is on the start of the line?

Regards,
Vyacheslav.

Dear Vyacheslav,

I think you can explanation here: viewtopic.php?f=3&t=383

Regards,

Didier

Dear Didier,

thanks for the link,
but, unfortunately, i did not fully understand if I simulate a single bunch (not CW) will I have a single bunch by using "Create a 360 deg period" button or there is one bunch destroyed into several?
In other words, what is it presented in longitudinal phase space without marking the checkbox "Create a 360 deg period" ?

Regards,
Vyacheslav

Dear Vyacheslav,

I'm not sure I understand your question!
The longitudinal space represents your longitudinal distribution, as found at the end of your lattice when your input distribution is a 360° long cluster. So, if you have dirfts, at the end your distribtion is oviously longuer than 360°

Regards,

Didier

Dear Didier,

formally there are not any separatricies and energy changes in the straight channel without bends and RF fields. So, why did longitudinal beam size become 1000 deg or greater when at the start it was 360 deg?

I can not understand.

Regards, Vyacheslav.

Dear Vyacheslav,

Yes, that's right, but you have put a large energy spread (spreadW) in your input beam, that's the reason.

Regards,

Didier

Dear Didier,

thanks a lot.

Regards,
Vyacheslav