a question about Phi_RF and Superpose field maps

[Dreamer]

Dear Didier：
I have question about meaning of phi_Rf and Superpose field maps， and I encountered some problems， the question is long , So I put it in PDF.

Best regards,
Li

[Dreamer]

And the frequency of my beam is 162.5MHz

[Didier]

Dear Li,

Please try this very simple example 2 time, changing the frequency:

DRIFT 0 100
FREQ 162.5
;FREQ 325
FIELD_MAP 7700 210 55 20 -1.36 1.36 0 0 electromagnetic 0
DRIFT 0 100
END

You'll see that in both cases, the resulting synchronous phase will not be the same. The SUPERPOSE or SET_SYNC_PHASE commands are not the problem here. It's quite normal for the field seen by the beam to depend on the frequency, and it's even written in your field equation: W = 2.π.Freq.

Regards,

Didier

[Dreamer]

Dear Didier：
Thank you very much for your answer，I may not have been clear about my question. In my question, lattice 3 hand lattice 4 have the same cell1,
but the cell2 of lattice 3 is

freq 325
lattice 3 1

DRIFT 85.13 20 0 0 0
FIELD_MAP 70 345.1 0 20 0.572458 1 0 0 solenoid 0
SET_SYNC_PHASE
FIELD_MAP 7700 210 -32 20 -1.5 1.5 0 0 electromagnetic 0
End

the cell2 of lattice 4 is

freq 325
lattice 3 1
DRIFT 85.13 20 0 0 0
superpose_map 0 0 0 0 0 0
FIELD_MAP 70 350 0 20 0.572458 1 0 0 solenoid 0
superpose_map 345.1 0 0 0 0 0
SET_SYNC_PHASE
FIELD_MAP 7700 210 -32 20 -1.5 1.5 0 0 electromagnetic 0
End

They have same length and frequency. The only difference is that in cell2, the solenoid part of the superposition field is removed, I think they should be in the same phase(phi_rf). but I got a different phase,

Best regards,
Li

[Didier]

Dear Li,

Sorry for my misunderstanding of your problem.
It's clearer now, and indeed this RF phase becomes false under the conditions you mention.
I've corrected the problem. Please upgrade your code.

Regards,

Didier

[Dreamer]

Dear Didier,
It works!


Best Regards
Li