A Preonic Model with Colour-Spin Symmetry
  We have constructed a preonic model starting from a coloured fermionic preon and by postulating a new symmetry, MUSY. This new symmetry is defined via the MU number involving colour, charge and spin properties of the preons. We show that all the known fields of the Standard Model (SM) can be constructed using the fermionic preon and 6 preonic scalars, its MUSY partners. As an example, we present well known \beta-decay process at MUSY level. MUSY also forbids some processes such as proton decay (preserving the baryon number) and hence, it is compatible with current experimental results. In this model the number of SM generations arises to be three naturally.   The MUSY generalization of the SUSY algebra is constructed and the MUSY invariant Lagrangian is also explicitly written. Similar to other preonic and supersymmetric models, a number of new particles are predicted. These particles do not interact with any of the SM fermions but only with the gauge bosons. These particles could be dark matter candidates. 
Oktay Do\u{g}ang\"un, Saleh Sultansoy, G\"okhan \"Unel
hep-ph