Appendix D Known Issues

A bug is present where a sampler attached to a bending magnet (RBend/SBend) will cause the magnetic field to fail to be set. The reference frame rotates correctly but the particle trajectory does not follow. To work around this issue, samplers should be attached to a marker rather than directly to the magnet. For example:

     dip: sbend,l=1*m, angle=0.1;
     temp: line=(dip);
     use, period=temp;
     sample, range=dip;

should be replaced by:

     dip: sbend,l=1*m, angle=0.1;
     dipMark: marker;
     temp: line=(dipMark,dip);
     use, period=temp;
     sample, range=dipMark;

Samplers attached to multiple instances of the same element incorrectly register hits only from the first instance in all such samplers. For example:

     drift1: drift, l=1*m;
     mark1: marker;
     line1: line=(mark1,drift1,mark1,drift1);
     sample, range=mark1[1];
     sample, range=mark1[2];

will incorrectly record hits at mark1[1] in the sampler attached to mark1[2]. To avoid this, samplers should be attached to uniquely named elements.

There is a known issue with the z parameter output to samplers. As particle data is output at the z location of the sampler, when the global position is transformed from global to relative coordinates z is identically zero. For a description of a particle's longitudinal position in the bunch, please use the parameter s instead.