Field Map Superposition with Rotation

[Abhishek]

Dear Didier,

I am working on superposing the corrector field map with the solenoid field, where both share the same field map length. I have modeled the Y-pair of correctors, and I was wondering if I could use the same Y-corrector field map with a 90-degree rotation while superposing it as the X-corrector field map, given that both X and Y corrector pairs are identical.

For example, I used the following to overlap the solenoid field map with the Y-corrector field map:

superpose_map 0
FIELD_MAP 70 400 0 20 1 0 0 0 ycor 0
superpose_map 0
FIELD_MAP 70 400 0 20 3.7857 0 0 0 Sol 0


Now, I would like to superpose the third field map, where I want to use the Y-corrector field map with a 90-degree rotation. I assumed that in the command:

SUPERPOSE_MAP Z0 X0 Y0 θ_Z0 θ_X0 θ_Y0


If I use θ_Z0=90° (for instance):

superpose_map 0 0 0 90 0 0
FIELD_MAP 70 400 0 20 1 0 0 0 ycor 0
superpose_map 0
FIELD_MAP 70 400 0 20 3.7857 0 0 0 Sol 0

It would work as if I had rotated the field map by 90 degrees. However, this approach does not seem to be functioning as expected.

Could you kindly suggest how I can achieve this rotation?

Thank you for your time and support.

Best regards,
Abhishek

[Didier]

Dear Adhishek,

That's normal, as it's written in the manual about SUPERPOSE_MAP command. “The optionnals parameter, X0 Y0 θzo θxo θyo are required when the following field map curves the reference trajectory (See Field map with curved reference trajectory). Another command is also needed to inform code to output frame.
In other words, these parameters are only used for field map curving trajectories and you can use this type of configuration using SUPRPOSE_MAP_OUT command, like following:

Superposed_map_out example
superpose_map_out 400 0 0 0 0 0
superpose_map 0 0 0 90 0 0
FIELD_MAP 70 400 0 20 1 0 0 0 ycor 0
superpose_map 0
FIELD_MAP 70 400 0 20 3.7857 0 0 0 Sol 0

Regards,

Didier