That didn’t take long
August 31, 2007
Three theoretical discussions of the Z(4430) state have shown up on hep-ph in the last couple of days:
- Rosner suggests it’s a rescattering effect in threshold production of D*(2010) D1(2420);
- Maiani, Polosa, and Riquer suggest it’s a true tetraquark state, the first radial excitation of the X(3872)/X(3876);
- Meng and Chao suggest it’s an actual resonance in D*(2010) D1(2420).
September 9, 2007 at 5:03 pm
Got a idea about 4430 and 3872: perhaps Maiani is only partly right and it is not the first radial excitation but the ground charged state, if the diquark cu happens to have a mass different from the diquark cd.
This is because I conjectured two years ago that the diquarks cu cc and uu could differ from the rest. It is not only that they are +4/3, but also they break a pretty (but half-baked) “hadronic supersymmetry” I described in hep-ph/0512065. I like it because it is sort of unique, it only works for three generations of quarks.
Well, anyway, for this idea to be valid, there are strong restrictions in the spectroscopy. X(3872) should be alone, no charged partners nor neutral ones, because the partner “cu CU” should be, hmm, around 4988?!. And Z(4430) should be only the charged thing, without neutral partners.