MethodicalAcceleratorDesign
Undocumented quadrupole fringe option
The command below shows that quadrupole has two parameters related to fringe "kill_ent_fringe" and "kill_exi_fringe". Setting them true, I assume, means no fringe for specific quadrupole in PTC tracking. However, it is not documented in the manual. Am I correct in my assumption? Also, what are "permfringe" and "bend_fringe"?
help,quadrupole; parameter: permfringe logical: false parameter: bend_fringe logical: false parameter: kill_ent_fringe logical: false parameter: kill_exi_fringe logical: false
Thank you, Anton
For MAD-X the kill_ent_fringe kills the fringe field for dipoles but has no effect for quarupoles. I don't know how it is dealt with in PTC.
These do look like PTC parameters. And PTC does have a quadrupole fringe field.
Yes, this is correct, but by default it is disabled for compatibility with MAD-X.
PTC_SETSWITCH, FRINGE=true;
Activates the quadrupole fringe field for elements b2, a2.
Best, Laurent.
The command below shows that quadrupole has two parameters related to fringe "kill_ent_fringe" and "kill_exi_fringe". Setting them true, I assume, means no fringe for specific quadrupole in PTC tracking. However, it is not documented in the manual. Am I correct in my assumption? Also, what are "permfringe" and "bend_fringe"?
They are special options tested in element fringe field in PTC, but I am not sure that they are propagated so far (to be tested…).
You can look at the code of PTC for exemple for fringe field of straight elements (scalar version) https://github.com/MethodicalAcceleratorDesign/MAD-X/blob/master/libs/ptc/src/Sh_def_kind.f90#L1198 Other CASEs follows.
help,quadrupole; parameter: permfringe logical: false parameter: bend_fringe logical: false parameter: kill_ent_fringe logical: false parameter: kill_exi_fringe logical: false
Thank you, Anton