New angles on top quark decay to a charged Higgs

Understand

To properly discover a charged Higgs Boson ($H^\pm$) requires its spin and couplings to be determined.

• We investigate how to utilize $\ttbar$ spin correlations to analyze the $H^\pm$ couplings in the decay $t\to bH^+\to b\tau^+\nu_\tau$.
• Within the framework of a general Two-Higgs-Doublet Model, we obtain results on the spin analyzing coefficients for this decay and study in detail its spin phenomenology, focusing on the limits of large and small values for $\tan\beta$.
• Using a Monte Carlo approach to simulate full hadron-level events, we evaluate systematically how the $H^\pm\to\tau^\pm\nu_\tau$ decay mode can be used for spin analysis.