Top-Quark Phenomenology in Models with Bilinearly and Spontaneously Broken R-parity

TL;DR

This paper investigates unconventional top-quark decays within supersymmetric models featuring spontaneously broken R-parity, highlighting potential large branching ratios and the capability of current collider data to probe these phenomena.

Contribution

It introduces an effective theory combining MSSM with bilinear R-parity breaking and analyzes its implications for top-quark decay modes, which is a novel approach.

Findings

Large branching ratios for t -> stau + b and t -> tau + sbottom decays.

Current Tevatron data already constrain the model parameters.

Potential for improved detection at Tevatron Run 2.

Abstract

We study unconventional decays of the top-quark in the framework of SUSY models with spontaneously broken R-parity. In particular we discuss an effective theory which consists of the MSSM plus bilinearly broken R-parity. We demonstrate that the decay modes t -> stau + b and t -> tau + sbottom can have large branching ratios even in scenarios where the tau-neutrino mass is very small. We show that existing Tevatron data already probe the theoretical parameters, with promising prospects for further improvement at the Run 2 of the Tevatron.