calculation of parasitic loss by resistive wall

[zhilong]

Dear Dr. Borland and all,
Recently I have been using a component called “WAKE” to compare with the analytical results of energy spread caused by the resistive wall effect. First, I calculated and derived the wakefield file named “wake_monopole_resistive_wall.sdds” using an analytical formula, then used this wakefield to calculate the energy spread induced in a relatively long beam bunch. Subsequently, we compared this calculated result with the corresponding analytical result mentioned below, which is given by A.Chao in his book named “Physics of Collective Beam in High Energy Accelerators” page 113. However, we find there are some discrepancies between the two.
The equation and comparasion picture are attached, and the lattice I used is also attached.


As can be seen from the Figure, although the trend of the line formed by the blue points calculated by Elegant is similar to that of the green solid line from the analytical formula, there are still significant deviations. In particular, the two results differ drastically in terms of the overall parasitic loss.
I don’t know where the problem is. Maybe, it is because I made an error in using the Elegant. Here is the Files I use when I do the tracking.
Thanks a lot if anyone also encountered such a problem like me and can help me to find the bug.