Generation of baryon asymmetry in the E6CHM

TL;DR

This paper proposes a mechanism within the E6 inspired composite Higgs model where baryon asymmetry is generated through CP violation involving pseudo-Nambu-Goldstone bosons, with potential LHC signatures.

Contribution

It introduces a novel baryogenesis scenario in the E6CHM framework involving pNGBs and CP violation, linking high-scale symmetry breaking to observable collider signatures.

Findings

Baryon asymmetry can be generated despite suppressed baryon number violation.

The pNGB scalar triplet is crucial for the asymmetry process.

Potential LHC signatures of the scalar triplet are identified.

Abstract

The strongly interacting sector in the E6 inspired composite Higgs model (E6CHM) with baryon number violation possesses SU(6)\times U(1)_L global symmetry. In the weakly-coupled sector of this model the U(1)_L symmetry associated with lepton number conservation is broken down to a Z^L_2 discrete symmetry, which stabilizes the proton. Near the scale f > 10 TeV the SU(6) symmetry is broken down to its SU(5) subgroup, giving rise to a set of pseudo-Nambu-Goldstone bosons (pNGBs) that involves the SM-like Higgs doublet, a scalar coloured triplet and a SM singlet boson. Because f is so high, all baryon number violating operators are sufficiently strongly suppressed. Nevertheless, in this variant of the E6CHM the observed matter-antimatter asymmetry can be induced if CP is violated. The pNGB scalar coloured triplet plays a key role in this process and leads to a distinct signature that may be detected at the LHC in the near future.