10.67 NIBEND—A numerically-integrated dipole magnet with various extended-fringe-field models.

A numerically-integrated dipole magnet with various extended-fringe-field models.
Parallel capable? : yes
GPU capable? : no
Back-tracking capable? : no






Parameter Name UnitsType Default

Description






L M double 0.0

arc length






ANGLE RADdouble 0.0

bending angle






E1 RADdouble 0.0

entrance edge angle






E2 RADdouble 0.0

exit edge angle






TILT double 0.0

rotation about incoming longitudinal axis






DX M double 0.0

misalignment






DY M double 0.0

misalignment






DZ M double 0.0

misalignment






FINT double 0.5

edge-field integral






HGAP M double 0.0

half-gap between poles






FP1 M double 10

fringe parameter (tanh model)






FP2 M double 0.0

not used






FP3 M double 0.0

not used






FP4 M double 0.0

not used






FSE double 0.0

fractional strength error






ETILT RADdouble 0.0

error rotation about incoming longitudinal axis






ACCURACY double 0.0001

integration accuracy (for nonadaptive integration, used as the step-size)






MODEL STRINGlinear

fringe model (hard-edge, linear, cubic-spline, tanh, quintic, enge1, enge3, enge5)






METHOD STRINGrunge-kutta

integration method (runge-kutta, bulirsch-stoer, modified-midpoint, two-pass modified-midpoint, leap-frog, non-adaptive runge-kutta)






SYNCH_RAD long 0

include classical, single-particle synchrotron radiation?






ADJUST_BOUNDARY long 1

adjust fringe boundary position to make symmetric trajectory? (Not done if ADJUST_FIELD is nonzero.)






NIBEND continued

A numerically-integrated dipole magnet with various extended-fringe-field models.






Parameter Name UnitsType Default

Description






ADJUST_FIELD long 0

adjust central field strength to make symmetric trajectory?






FUDGE_PATH_LENGTH long 1

fudge central path length to force it to equal the nominal length L?






FRINGE_POSITION long 0

0=fringe centered on reference plane, -1=fringe inside, 1=fringe outside.






GROUP stringNULL

Optionally used to assign an element to a group, with a user-defined name. Group names will appear in the parameter output file in the column ElementGroup






For the NIBEND element, there are various fringe field models available. In the following descriptions, lf is the extend of the fringe field, which starts at z = 0 for convenience in the expressions. Also, K = 1g -Fy(z)(1 -Fy(z))dz is K. Brown’s fringe field integral (commonly called FINT), where g is the full magnet gap and ⃗
F = ⃗
B∕B0, B0 being the value of the magnetic field well inside the magnet.

NISEPT