Conveners
BSM IV
- Zhen Liu (Fermilab)
I will discuss the collider and dark matter phenomenology of models of portal matter which is responsible for generating the kinetic mixing between the SM and the dark photon at 1-loop. Both top-down (based on the group SU(8)) and bottom-up model building approaches will be discussed.
We explore signals of two Higgs bosons and missing energy at the LHC. Such a signal is characteristic of models for dark matter or other secluded particles that couple to the standard model through scalar mediators. I discuss our search strategy for these new particles, based on their decay topology into a final state with two b-jet pairs and missing transverse energy. The di-Higgs channel is...
In Higgs portal models of fermion dark matter, scalar couplings are unavoidably suppressed by strong bounds from direct detection experiments. As a consequence, thermal dark matter relics must coexist with mediators in a compressed spectrum of dark particles. Small couplings and small mass splittings lead to slow mediator decays, leaving signatures with displaced vertices or disappearing...
Dynamical Dark Matter (DDM) is an alternative framework for dark-matter physics in which the dark sector consists of large ensembles of dark states which exhibit a broad range of masses and lifetimes. While some of the states in this ensemble must be sufficiently long-lived that they contribute to the dark-matter abundance at present time, other states in the ensemble may have far shorter...
A preponderance of astrophysical and cosmological evidence indicates that the universe contains not only visible matter but also dark matter. In order to suppress the couplings between the dark and visible sectors, a standard assumption is that these two sectors communicate only through a mediator. In this talk we make a simple but important observation: if the dark sector contains multiple...
Extensions of the Standard Model are often highly constrained by cosmology. The presence of new states can dramatically alter observed properties of the universe by the presence of additional matter or entropy. Especially if those new states exist near the weak scale and thermal contact brings new particles into equilibrium. Without a means to deposit this energy into the SM, often these...
