CEA Codes forum

Dear Didier,

I want to simulate a RFQ fieldmap + MEBT, and get the envelop of the linac.
Considering the output of RFQ fieldmap has multiple bunches，i adopt the following syntax to get the envelop and use the modified RFQ fieldmap output (merged into one bunch) as the input for MEBT.

DRIFT 0.00001 1000
DRIFT 0.00001 1000
DRIFT 0.00001 1000
RFQ_GAP_RMS_FFS 6.0766 6.2147
READ_OUT D:\Shuo\Tracewin\Isotope-2025\AllLinac\rfq_toutatis.out
RFQ_CELL 68000 3.751 0 1 17.012 -90 3 2.814 1 3.75
RFQ_CELL 68000 3.751 8e-005 1.0005 4.254 -90 4 2.814 0 3.75
lattice 2
RFQ_CELL 68000 3.751 0 1.001 4.254 -89.96 -2 2.814 0.0001 3.749
RFQ_CELL 68000 3.751 0.00025 1.0016 4.254 -89.94 2 2.814 0.0001 3.748
..................
lattice_end
RFQ_CELL 68000 3.751 0 1.8525 29.931 -50.72 -4 2.814 0 3.751
RFQ_CELL 68000 3.751 0 1 18 -90 -3 2.814 0 3.751
READ_DST D:\Shuo\Tracewin\Isotope-2025\AllLinac\rfq_Fldmap.dst
DRIFT 0.00001 1000
DRIFT 0.00001 1000
DRIFT 0.00001 1000

; ******MEBT******
........

The issue is that the position of the output is much longer than the linac. And the output seems incorrect. Regards,
Shuo

Dear Shuo,

It's just a display problem that's been corrected in the latest version.

Regards,

Didier

Dear Didier,

I have download the latest version, and the display problem is fixed.
Here, i have another problem. When i try to add a DTL filedmap following the MEBT and run it with RFQ. The final output is incorrect.
If i remove the RFQ part in the .dat and run it in another separate file, it works. Plz see the below:
And i attached all the files to test. The two input .ini files share the same input fieldmap.
(The input .dst in IHDTLs_Fldmap.ini is the same as the rfq_Fldmap.dst)

Regards,
Shuo

Dear Shuo,

Clearly, what is indicated in the manual has misled you. I'll have to review what is recommended, because it doesn't seem right when a READ_OUT is used.
You should use the following line:

"CHANGE_BEAM 2 0 0 0 -75500 0 0 39075.282 39075.782"

Regards,

Didier