New data for X(3872) production in B decays provide a separation between Xproduction and decay, sharpen several experimental puzzles and impose seriousconstraints on all models. Both charged and neutral B decays produce a narrowneutral resonant state that decays to both J/\psi \rho and J/\psi \omega, whileno charged resonances in the same multiplet are found. This suggests that the Xis an isoscalar resonance whose production conserves isospin, while isospin isviolated only in the decay by an electromagnetic interaction allowing theisospin-forbidden J/\psi \rho decay. A tetraquark isoscalar X model is proposedwhich agrees with all present data, conserves isospin in its production andbreaks isospin only in an electromagnetic X(3872) --> J/\psi \rho^o decay. Thenarrow X decay width results from the tiny phase space available for the J/\psi\omega decay and enables competition with the electromagnetic isospin-forbiddenJ/\psi \rho decay which has much larger phase space. Experimental tests areproposed for this isospin production invariance.
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