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تسجيل مستخدم جديدStudy of an anomalous tau lepton decay using a chiral Lagrangian with vector mesons
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The hadronic tau decay $tau^- to u_tau eta pi^- pi^0$ occurs through V-A weak current. In this decay mode, the vector current contribution is intrinsic parity violating and the axial current contribution is G parity violating. The latter contribution is suppressed due to tiny isospin breaking. We have computed both vector and axial vector form factors using a chiral Lagrangian with vector mesons including the effect of isospin breaking and intrinsic parity violation. A numerical result of the invariant mass distribution is shown and the structure of $rho$ resonance can be seen in the distribution with respect to $M_{pi^- pi^0}$.
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