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Using pi_2(1670) -> b_1(1235) pi to Constrain Hadronic Models

Philip R. Page·Simon Capstick
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Abstract

We show that current analyses of experimental data indicate that the strong decay mode pi_2 -> b_1 pi is anomalously small. Non-relativistic quark models with spin-1 quark pair creation, such as ^3P_0, ^3S_1 and ^3D_1 models, as well as instanton and lowest order one-boson (in this case pi) emission models, can accommodate the analyses of experimental data, because of a quark-spin selection rule. Models and effects that violate this selection rule, such as higher order one-boson emission models, as well as mixing with other Fock states, may be constrained by the small pi_2 -> b_1 pi decay. This can provide a viability check on newly proposed decay mechanisms. We show that for mesons made up of a heavy quark and anti-quark, the selection rule is exact to all orders of Quantum Chromodynamics (QCD) perturbation theory.

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Philip R. Page, Simon Capstick. 2003-07-01. Using pi_2(1670) -> b_1(1235) pi to Constrain Hadronic Models. https://doi.org/10.1016/s0370-2693(03)00804-9

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