Mixing Angle of Hadrons in QCD: A New View

Understand

A new method for calculation of the mixing angle between the hadrons within QCD sum rules is proposed.

• In this method, the mixing is expressed in terms of quark and gluon degrees of freedom.
• As an application, the detailed calculation of the mixing angle between heavy cascade baryons Xi_Q and Xi_Q', Q=c,~b is presented and it is found that the mixing angle between Xi_b (Xi_c) and Xi_b' (Xi_c') is given by theta_b = 6.4^\circ \pm 1.8 ^\circ (theta_c = 5.5^\circ \pm 1.8^\circ).