Higgs production in CP-violating supersymmetric cascade decays: probing the `open hole' at the Large Hadron Collider

TL;DR

This paper investigates how the LHC can detect Higgs bosons in a CP-violating supersymmetric scenario, especially targeting the unexcluded parameter space using cascade decays and multi-lepton signals with early data.

Contribution

It introduces a novel multi-channel analysis strategy to probe the CPX-scenario at the LHC, focusing on background-free multi-lepton final states with low luminosity.

Findings

LHC can probe the 'hole' in the parameter space with early data.

Multi-lepton channels are nearly background free at 5-10 fb$^{-1}$.

Significant 5σ signals are achievable at 14 TeV and 7 TeV energies.

Abstract

A benchmark CP-violating supersymmetric scenario (known as 'CPX-scenario' in the literature) is studied in the context of the Large Hadron Collider (LHC). It is shown that the LHC, with low to moderate accumulated luminosity, will be able to probe the existing `hole' in the $m_{h_1}$-$\tan\beta$ plane, which cannot be ruled out by the LEP data. We explore the parameter space with cascade decay of third generation squarks and gluino with CP-violating decay branching fractions. We propose a multi-channel analysis to probe this parameter space some of which are background free at an integrated luminosity of 5-10 fb$^{-1}$. Specially, multi-lepton final states ($3\l,\, 4\l$ and like sign di-lepton) are almost background free and have $5\sigma$ reach for the corresponding signals with very early data of LHC for both 14 TeV and 7 TeV center of mass energy.