intended for debug purposes only, as 
follows. When more than one valence quark is kicked out of a baryon 
beam, as part of the multiparton interactions scenario, the subsequent
hadronization is described in terms of a junction string topology.
This description involves a number of technical complications that
may make the program more unstable. As an alternative, by switching
this option off, junction configurations are rejected (which gives 
an error message that the remnant flavour setup failed), and the