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Dipole matrix with FSE

Posted: 12 Feb 2018, 09:15
by hbiss
Dear all,

This is not a problem with elegant itself but I ran in some problems understanding basic dipole matrix elements.

I had a look in the elegant source code to understand how the dipole matrix (for instance a simple SBEN without any edge effects) is affected by introducing an FSE und thus changing the actual curvature ha and finally the matrix elements.
I am certain that my calculations (using the matrix from A. Wolski, "Beam Dynamics in High Energy Particle Accelerators" p.95, and setting h=h_elegant,k_0=ha_elegant)) have still some major flaw, as I am not able to reproduce all matrix elements with this strategy. I am able to do reproduce the SBEN matrix by using the same definition kx2 = -(h2 - 2*h*ha + nh*ha) as in the elegant sources (instead of the definition in Wolski, kx2=wx2 = h*k0+k1) and multiplying R_x6 by (1 + FSE).

My question: Do you know some further literature where dipole matrices with a h != k0 are discussed? Or even better, where the elegant source is based upon?

Many thanks!
Hauke

Re: Dipole matrix with FSE

Posted: 19 Feb 2018, 10:09
by michael_borland
Hauke,

Unfortunately, I don't have anything written down about this. I based my development on Karl Brown's old SLAC-75 article. Looking through this, I identified which occurrences of h were related to the field strength and which to the coordinate system.

Sorry for not having more details.

--MIchael