Dark matter in Hidden Valley models with stable and unstable light dark mesons

• Published in: The journal of high energy physics 2019-04, Vol.2019 (4), p.1-24, Article 118
• Main Authors: Beauchesne, Hugues, Bertuzzo, Enrico, Grilli di Cortona, Giovanni
• Format: Article
• Language: English
• Subjects: Apexes; Beyond Standard Model; Classical and Quantum Gravitation; Cosmology of Theories beyond the SM; Dark matter; Elementary Particles; Fermions; High energy physics; Mathematical models; Mesons; Parameters; Particle decay; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Regular Article - Theoretical Physics; Relativity Theory; Signatures; Standard model (particle physics); String Theory; Viability
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP04(2019)118

A bstract It is a distinct possibility that a Hidden Valley sector would have a spectrum of light particles consisting of both stable and unstable dark mesons. The simultaneous presence of these two types of particles can lead to novel mechanisms for generating the correct dark matter relic abundance, which in turn can reflect themselves into new exotic signatures at colliders. We study the viability of such sectors for various Hidden Valley models and map the valid parameter space to possible collider signatures. Mediators studied include various scalar bifundamentals and a heavy Z ′. It is shown that in general bounds from direct and indirect detection can easily be avoided. In most of the allowed parameter space, the relic density is determined by stable mesons annihilating to unstable ones which in turn decay quickly to Standard Model particles. Dark mesons that decay mainly to heavier Standard Model fermions allow for more valid parameter space, though dark mesons are still allowed to decay exclusively to some of the lighter fermions. Possible exotic collider signatures include displaced vertices, emerging jets and semivisible jets.