The sum of the factorizable long- and short-distance c (c) over bar contributions to the B --> K*gamma amplitude vanishes as a consequence of the gauge invariance. Moreover, the short- and long-distance contributions vanish, separately, if defined in a gauge-invariant way. In view of this, we dispute a popular estimate of the long-distance effects in the B --> K*gamma decay in terms of the B --> K* semileptonic form factors and the decay constants of the c (c) over bar resonances. We show that a nonzero value obtained within this approach is an artifact of using a gauge-dependent prescription for the resonance contribution extended to q(2) = 0. (C) 2001 Elsevier Science B.V. All rights reserved. References: 10
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机译：可分解的长距离和短距离 c （c） 对 B --> K*gamma 振幅的贡献之和由于规范不变性而消失。此外，如果以规范不变的方式定义，短距离和长距离贡献将分别消失。有鉴于此，我们根据B--> K*半轻子形状因子和c（c）在条形共振上的衰减常数，对B--> K*γ衰变的长距离效应的流行估计提出了异议。我们表明，在这种方法中获得的非零值是使用规范相关处方来扩展共振贡献到q（2） = 0的产物。（C） 2001 Elsevier Science B.V.保留所有权利。[参考文献： 10]
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