Trajectory in Dipole Parallel-T
Observation
In the comparison of the created maps form Thick Tracker
(which I am working on) and the maps of Cosy Infinity , I have noticed a difference between the dipole maps.
The COSY 10.0 input: CompBend.fox cosy.fox
In the closer look: the Thick Tracker
algorithm uses the parameter ElementLength
, which is the value L
of the Input.in
- file.
class ElementBase
...
/// Get design length.
// Return the design length defined by the geometry.
// This may be the arc length or the straight length. <-----
inline
double ElementBase::getElementLength() const
{ return getGeometry().getElementLength(); }
The ElementLength
in a SectorBend
is the straight Trajectory in between the entrance and exit point of the ref particle, as documented.
form: https://gitlab.psi.ch/OPAL/src/wikis/Manual/elements
BUT if I now compare the THICK TRACKER
with PARALLEL-T
, like in the issue #215 (closed), it won't match this smoothly.
70MeV_Gantry2.in MAPS 70MeV_Gantry2.in TRACK
The two map generated Codes differ in the use of either the straight or the curved trajectory for the creation of the dipole map. (In the curved implementation I just changed the map, but not its position to visualize the effect of this change.)
Suggested Solution
After that comparison, I think that there might be a bug in the SectorBend
, which probably is just the use of the straight instead of the curved trajectory.