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Dipole negative K0

When I compare (opal 1.6 and opal 1.9) the beam line of the PSI Gantry 2, I have noticed the problem, that negative K0 values of the Dipole AMF2 cause troubles (maybe in the creation of the reference trajectory). Even, an alternative Implementation with a positive K0 and a rotation (PSI) of pi doesn't solve the problem and gives the same output.

The Implementation of the dipole is:

AMF2:   SBEND, 
        K0=-0.804017,      //<--- negative magnetic field strength 
        L=1.4929, 
	ELEMEDGE=42.6615,
        FMAPFN="HardEdge.T7", 
        //PSI = Pi,         //<---- Rotate like that
        DESIGNENERGY=7.381e+01, GAP=.1;

Normal_AMF2

NOTE: Why do I think, that the negative K0 causes the problem? Because just some elements before the dipole AMF1 has precisely the same attributes, except a positive K0 and matches the with OPAL 1.6.

The complete .in are here. 70MeV_Gantry2_OPAL1.6.in & 70MeV_Gantry2_OPAL1.9.in

The Fieldmap: HardEdge.T7

If I use positive K0 values, the rms of OPAL 1.6 and OPAL 1.9 match again. Plot below (made out of .stat file made with pyOPAL Tools) positive_K0_AMF2

Does someone has an idea where this missmatch come from?