Page 1 of 1
frequency map
Posted: 23 Sep 2026, 02:16
by Samira.kasaei
Dear Michael,
I am calculating frequency map for my lattice. I added the frequency map calculated by AT, that shows discrepancy between AT and elegant. I increased the n_passes or n_kicks in my lattice but I didn't get better results.
And Could please let me how I can plot the tune frequency map with integer numbers included(7.23,6.19 in my case like the AT one)?
Many thanks in advance for your helpful comments,
Samira
Re: frequency map
Posted: 23 Sep 2026, 10:14
by michael_borland
Samira,
You can offset the x and y axes values by the integer tunes using the -offset option in sddsplot, e.g.,
Code: Select all
sddsplot -col=nux,nuy fma_1.fma -graph=sym,vary=subtype,fill -split=col=diffusionRate -order=spect -offset=xch=7,ych=6 -scale=7.2,7.28,6,6.4
Looking at your lattice file, I noticed that you included an RF cavity, which isn't recommended for FMA. Also, the CSBEND element is not using sufficient number of slices for good results; see attached for recommended settings. Finally, the chromaticities are both negative.
--Michael
Re: frequency map
Posted: 13 Oct 2026, 02:22
by Samira.kasaei
Dear Michael,
Thank you for your reply.
I tried the new lattice however i didnt get a closer result to AT
.
I do appreciate if you have any other comment in this topic.
Many thanks and best regards,
Samira
Re: frequency map
Posted: 13 Oct 2026, 10:24
by michael_borland
Samira,
I'm not sure what the issue might be. We compared elegant and AT in the past for nonlinear dynamics and found good agreement. See
this paper.
--Michael
Re: frequency map
Posted: 05 Nov 2026, 07:04
by koryun
Daer Samira,
Sorry for jumping in, but looking at my old AT lattice for SESAME, I noticed that the sextupole strengths have the same numerical values as those in your elegant lattice. However, the multipole-strength definitions in AT and elegant are different, so you need to multiply the sextupole strengths from AT by a factor of 2 when converting them to elegant.
Koryun