∫
-∞∞Fy(z)(1 -Fy(z))dz is K. Brown’s fringe field integral (commonly called FINT), where g is
the full magnet gap and 
= 
∕B0, B0 being the value of the magnetic field well inside the
magnet.
A numerically-integrated dipole magnet with various extended-fringe-field models.
Parallel capable? : yes
GPU capable? : no
Back-tracking capable? : no
| Parameter Name | Units | Type | Default | Description |
| L | M | double | 0.0 | arc length |
| ANGLE | RAD | double | 0.0 | bending angle |
| E1 | RAD | double | 0.0 | entrance edge angle |
| E2 | RAD | double | 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 | RAD | double | 0.0 | error rotation about incoming longitudinal axis |
| ACCURACY | double | 0.0001 | integration accuracy (for nonadaptive integration, used as the step-size) |
|
| MODEL | STRING | linear | fringe model (hard-edge, linear, cubic-spline, tanh, quintic, enge1, enge3, enge5) |
|
| METHOD | STRING | runge-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 | Units | Type | 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 | string | NULL | 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 = ∫
-∞∞Fy(z)(1 -Fy(z))dz is K. Brown’s fringe field integral (commonly called FINT), where g is
the full magnet gap and = ∕B0, B0 being the value of the magnetic field well inside the
magnet.
For this model, the user specifies FINT and HGAP only.
.
The user may choose “enge1”, “enge3”, or “enge5”, where the number indicates the order of the expansion of Fz with respect to y.
The need only specify FINT and HGAP. The Enge parameters are then automatically determined to give the correct linear focusing.
However, if user gives non-zero value for FP2, then FINT and HGAP are ignored. FP2, FP3, and FP4 and taken as the Enge coefficients a1, a2, and a3, respectively.
NISEPT