Elegant users forum

Hi,

I set up feedbacks for both main RF and 3rd harmonic cavities, as showing in the attached file. However, particles are lost after tens of turns. BTW, this is just half of the current that the machine aims for. The way that I set up feedback for the third harmonic cavity is to hold the cavity's voltage and phase at its optimum value, which is calculated by formula. Can you please check what I did wrong ? thank you so much,

regards,
wencan

Wencan,

I don't see any obvious problem with your setup. I suggest trying the following

1. Replace both cavities by RFCA elements with the same phase and voltage, to verify that these are correct.
2. If that works, revert to RFMODE for the main cavity, which should also work.
3. If that works, try a very low current case with RFMODE for both cavities.
4. If that works, try slowly ramping the current from zero (use &modulate_elements).

--Michael

Thank you very much. I am trying it.

Wencan