0000000000420180
AUTHOR
Claire H. Shepherd-themistocleous
Long-lived particles at the energy frontier: the MATHUSLA physics case
We examine the theoretical motivations for long-lived particle (LLP) signals at the LHC in a comprehensive survey of Standard Model (SM) extensions. LLPs are a common prediction of a wide range of theories that address unsolved fundamental mysteries such as naturalness, dark matter, baryogenesis and neutrino masses, and represent a natural and generic possibility for physics beyond the SM (BSM). In most cases the LLP lifetime can be treated as a free parameter from the $\mu$m scale up to the Big Bang Nucleosynthesis limit of $\sim 10^7$m. Neutral LLPs with lifetimes above $\sim$ 100m are particularly difficult to probe, as the sensitivity of the LHC main detectors is limited by challenging …
Review of LHC experimental results on low mass bosons in multi Higgs models
A number of searches at the LHC looking for low mass ($2m_{\mu} - 62\ \mathrm{GeV}$) bosons in $\sqrt{s} = 8\ \mathrm{TeV}$ data have recently been published. We summarise the most pertinent ones, and look at how their limits affect a variety of supersymmetric and non-supersymmetric models which can give rise to such light bosons: the 2HDM (Types I and II), the NMSSM, and the nMSSM.