$h^0(125GeV) \to c \bar{c}$ 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 in the MSSM with quark flavor violation, showing it can significantly deviate from the Standard Model prediction due to SUSY QFV effects, potentially observable at future colliders.

Contribution

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

Findings

Decay width can differ up to ±35% from SM prediction.

Large scharm-stop mixing enhances sensitivity to QFV parameters.

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

Abstract

We calculate the decay width of $h^0(125GeV) \to c \bar{c}$ in the Minimal Supersymmetric Standard Model (MSSM) with non-minimal quark flavor violation (QFV) at full one-loop level. We adopt the $\overline{\rm DR}$ renormalization scheme. We study the effects of the mixing of the second and third squark generations (i.e. scharm-stop mixing) on the decay width, respecting the experimental constraints from B-meson data, the Higgs mass measurement and supersymmetric (SUSY) particle searches. We show that the decay width $\Gamma (h^0 \to c \bar{c})$ at the full one-loop level is very sensitive to the SUSY QFV parameters. In a scenario with large scharm-stop mixing, the decay width can differ up to $\sim \pm 35\%$ from its SM prediction. After taking into account the experimental and theoretical uncertainties of the decay width, we conclude that these QFV SUSY effects can be observed at a future $e^+ e^-$ collider such as ILC (International Linear Collider).