Mixing of X and Y states from QCD sum rules analysis

We study (Q) over barQ (q) over barq and (Q) over bar qQ (q) over bar states as mixed states in QCD sum rules. By calculating the two-point correlation functions of pure states of their corresponding currents, we review the mass and coupling constant predictions of J(PC) = 1(++), 1(--), and 1(-+) states. By calculating the two-point mixed correlation functions of (Q) over bar QQ (q) over barq and (Q) over bar qQ (q) over bar currents, we estimate the mass and coupling constants of the corresponding "physical state" that couples to both (Q) over barQ (q) over barq and (Q) over bar qQ (q) over bar currents. Our results suggest that for 1(++) states, the (Q) over barQ (q) over barq and (Q) over bar qQ (q) over bar components are more likely to mix, while for 1(--) and 1(-+) states, there is less mixing between (Q) over barQ (q) over barq and (Q) over bar qQ (q) over bar. Our results suggest the Y series of states have more complicated components.