Magnetic moment of $X_Q$ state with $J^{PC}=1^{+\pm}$ in light cone QCD   sum rules
  The magnetic moments of the recently observed resonance $X_b(5568)$ by DO Collaboration and its partner with charm quark are calculated in the framework of the light cone QCD sum rules, by assuming that these resonances are represented as tetra--quark states with quantum numbers $J^{PC}=1^{+\pm}$. The magnetic moment can play critical role in determination of the quantum numbers, as well as giving useful information about the inner structure of these mesons. 
A. K. Agamaliev, T. M. Aliev, M. Savc{\i}
hep-ph