The XYZ's of cc: Hints of Exotic New Mesons

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I discuss the nature of the new charm and charmonium like states observed in the last few years and measurements that can test these assignments. In particular it appears that the X(3943) is the etac''(3¹S₀) which can be tested by looking for it in gamma gamma to DD*, the Y(3943) is the chic₁'(2³P₁) which can be tested by looking for it in DD and DD*, the Z(3930) is the chic₂'(2³P₂) which can be confirmed by looking for it in DD*. If the X(3872) is confirmed to have JPC=1⁺⁺ it is almost certainly a multiquark state while if its JPC is found to be 2⁻⁺ is is likely the 1¹D₂ state. The Y(4260) appears to be an extra 1⁻⁻ which is most easily explained as a charmonium hybrid. This can be tested by looking the DD₁ final state.