Dispersion theoretic calculation of the $H\to Z+\gamma$ amplitude

Abstract

We have calculated the $W$-loop contribution to the amplitude of the decay $H\to Z+\gamma$ in two different methods: 1) in the $R_{\xi }$-gauge using dimensional regularization (DimReg), and 2) in the unitary gauge through the dispersion method. Using the dispersion method we have followed two approaches: i) without subtraction and ii) with subtraction, the subtraction constant being determined adopting the Goldstone boson equivalence theorem (GBET) at the limit $M_W\to 0$. The results of the calculations in $R_{\xi }$-gauge with DimReg and the dispersion method with the GBET completely coincide, which shows that DimReg is compatible with the dispersion method obeying the GBET.

16 pages with 15 figures, changes in Sec. IVB, references added

References in corpus (5)

• Direct extraction of one-loop integral coefficients
• A Numerical Unitarity Formalism for Evaluating One-Loop Amplitudes
• D-dimensional unitarity cut method
• FeynHelpers: Connecting FeynCalc to FIRE and Package-X
• Analytic Structure of Three-Mass Triangle Coefficients

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• Divergences in the effective loop interaction of the Chern-Simons bosons with leptons. The unitary gauge case
• The dispersion method and dimensional regularization applied to the decay $H\to Z\gamma$
• Rare Higgs Decay into a Photon and a Z Boson in Radiatively-Driven Natural Supersymmetry