## Energy dynamics simulation

Moderators: cyao, michael_borland

Hwang, Ji-Gwang
Posts: 35
Joined: 21 Jan 2010, 02:27

### Energy dynamics simulation

Dear Michael borland

Hello. I would like to observe the beam orbit changing over 1 Million turns as a result of the energy variation due to the radiation damping by the large orbit oscillation when the excitation signal was given.

Then, I put the CSBEND with radiation damping (USE_RAD_DIST=1) and RFCA (cavity) with fixed reasonable phase (not 180 degree) and T_REFERENCE=0 in the lattice file. The excitation signal is give by the MAL element with the modulation comments.
When the a few urad kick was given, the oscillation with the amplitude of 100 ~ 200 um is observed.
But the energy is constant over 1 Million turns. Could you explain what's wrong or how can I do it if it is possible?

Best regards

Ji-Gwang Hwang

michael_borland
Posts: 1796
Joined: 19 May 2008, 09:33
Location: Argonne National Laboratory
Contact:

### Re: Energy dynamics simulation

Ji-Gwang,

I'm not 100% sure what you are trying to do. Can you post an example?

--Michael

Hwang, Ji-Gwang
Posts: 35
Joined: 21 Jan 2010, 02:27

### Re: Energy dynamics simulation

Dear Micheal Borland

I am sorry too poor my explanation. I will post the example as soon as possible.

The kicker (MAL element) putted in the lattice file and modulation comment is on .ele file to give the time varying kick with certain frequency.
And the frequency is the betatron sideband. Then I observed the oscillation of the horizontal beam orbit due to the horizontal and longitudinal coupling.
The amplitude of the horizontal oscillation is a few hundred micrometer.

As I think, the particle should have more radiation energy loss than synchronous particle and moving around the synchronous phase.
Then it should going to different equilibrium state (orbit). But the energy is constant over 1 Million turns on the in my calculation.
Is it possible to do this kind of dynamic simulation with elegant?

Best regards

Ji-Gwang Hwang

michael_borland
Posts: 1796
Joined: 19 May 2008, 09:33
Location: Argonne National Laboratory
Contact:

### Re: Energy dynamics simulation

Ji-Gwang,

Here's an example that might help. See the 'runScript' file for details.

--Michael
Attachments
tuneExcitation.zip