Systematics of Large Axial Vector Meson Production in Heavy Flavor Weak Decays

Large branching ratios observed for D and B decays to final states containing the a1(1260) ± are comparable to those for corresponding decays to states containing a charged pion or a charged ρ, and much larger than those for all other decays. Implications are discussed of a “vector-dominance model” in which a W is produced and immediately turns into an axial vector, vector or pseudoscalar meson. Data for decays to all such final states are examined and shown to have large branching ratios and satisfy universality relations. The model predicts branching ratios of the order of 1% for the as yet unobserved B decays into states containing the Ds1(2536) charmed-strange axial vector meson. I. A VECTOR-DOMINANCE MODEL FOR HEAVY-FLAVOR DECAYS A. Systematics of quasi-two-body decays The large branching ratios observed [1] for the appearance of the a1(1260) ± in all quasitwo-body decays D → Xa1(1260)± and B → Xa1(1260)± are comparable to those observed Supported in part by grant from US-Israel Bi-National Science Foundation and by the U.S. Department of Energy, Division of High Energy Physics, Contract W-31-109-ENG-38.