Twiss Matching

[Jafarinia]

Hi Michael,

I have been trying to match 6 parameters at the end of the beam line (betax, betay, alphax, alphay, etax and etaxp). I am using 6 quadrupoles . I tried many times with different starting values (random number generator for initial k value for each quad) but ELEGANT was not able to find the solution (although there is a range for the tolerance in sene constraint).

Since there are 6 parameters for matching, with 6 quads I expect a solution for my problem. Is that true or it doesn't work for some cases?
I was wondering if there is a better way to find the solution.

Thank you in advance,
Farzad

[michael_borland]

Farzad,

I think it is possible that there is no solution even with six quadrupoles. The reason is that the quantities are not entirely independent. For example, the dispersion and beta function in the horizontal plane tend to follow similar patterns.

--Michael