$h^0 \to c \bar{c}$ as a test case for quark flavor violation in the MSSM

TL;DR

This paper calculates the decay width of the Higgs boson to charm quarks within the MSSM considering quark flavor violation, showing it can significantly deviate from the Standard Model prediction and could be observed at future colliders.

Contribution

It provides a full one-loop level calculation of $h^0 o c ar{c}$ decay in the MSSM with quark flavor violation, highlighting the impact of $ ilde{c}- ilde{t}$ mixing.

Findings

Decay width can differ by up to ±35% from SM value due to QFV.

Full one-loop corrections are highly sensitive to MSSM QFV parameters.

Potential observability of SUSY QFV effects at future $e^+ e^-$ colliders.

Abstract

We compute the decay width of $h^0 \to c \bar{c}$ in the MSSM with quark flavor violation (QFV) at full one-loop level adopting the $\overline{\rm DR}$ renormalisation scheme. We study the effects of $\tilde{c}-\tilde{t}$ mixing, taking into account the constraints from the B meson data. We show that the full one-loop corrected decay width $\Gamma (h^0 \to c \bar{c})$ is very sensitive to the MSSM QFV parameters. In a scenario with large $\tilde{c}_{L,R}-\tilde{t}_{L,R}$ mixing $\Gamma (h^0 \to c \bar{c})$ can differ up to $\sim \pm 35\%$ from its SM value. After estimating the uncertainties of the width, we conclude that an observation of these SUSY QFV effects is possible at an $e^+ e^-$ collider (ILC).