Dark Matter and Enhanced Higgs to Di-photon Rate from Vector-like Leptons
Abstract
In this paper, we study an extension of the standard model with a vector-like generation of leptons. This model provides a viable dark matter candidate and a possibility to enhance the Higgs decay rate into a pair of photons. We evaluate constraints from electroweak precision tests and from vacuum stability, and find that the latter provide an upper limit on the lepton Yukawa couplings. A large enhancement of the Higgs di-photon rate can therefore only be obtained when the mass of the lightest charged lepton is close to the LEP limit. The relic density constraint suggests a co-annihilation scenario with a small mass difference between the lightest charged and neutral leptons, which also weakens the LEP limit on the lightest charged lepton mass and allows for larger Higgs di-photon decay rates. Cross sections for direct detection of the dark matter candidate are calculated, and prospects for detecting the new particles at the LHC are discussed briefly.
Keywords
Cite
@article{arxiv.1207.4235,
title = {Dark Matter and Enhanced Higgs to Di-photon Rate from Vector-like Leptons},
author = {Aniket Joglekar and Pedro Schwaller and Carlos E. M. Wagner},
journal= {arXiv preprint arXiv:1207.4235},
year = {2015}
}
Comments
22 pages, 8 figures; v2: Updated with new Xenon 100 results, added references; v3: Fixed typo in Eqn. (A.19), published in JHEP