rf_setup return <0 values for Ss & Sdelta
Posted: 18 Apr 2018, 16:07
Hello,
I was wondering what is the meaning of Ss0 and Sdelta0 and how they are computed in rf_setup. For the example attached I am puzzled as the rf_setup returns negative values for these two variables. Also, I am surprised by the magnitude of Sdelta [O(10**-10)] assuming there is just an issue with the sign. If I just use these value as input for my sddsbeam, I see the beam is longitudinally mismatched. It there an easy way to find out the ideal initial longitudinal beam parameter to be matched and avoid large oscillation in bunch length and energy spread?
Thank you, -- Philippe.
I was wondering what is the meaning of Ss0 and Sdelta0 and how they are computed in rf_setup. For the example attached I am puzzled as the rf_setup returns negative values for these two variables. Also, I am surprised by the magnitude of Sdelta [O(10**-10)] assuming there is just an issue with the sign. If I just use these value as input for my sddsbeam, I see the beam is longitudinally mismatched. It there an easy way to find out the ideal initial longitudinal beam parameter to be matched and avoid large oscillation in bunch length and energy spread?
Thank you, -- Philippe.