Conveners
Dark Sectors and Cosmology
- Jonathan Lee Feng (University of California Irvine (US))
We identify potentially the world's most sensitive location to search for millicharged particles in the 10 MeV to 100 GeV mass range: the forward region at the LHC. We propose constructing a scintillator-based experiment, FORward MicrOcharge SeArch (FORMOSA) in this location, and estimate the corresponding sensitivity projection. We show that FORMOSA can discover millicharged particles in a...
In this talk, I will present some additional physics potential of FORMOSA, that not only provides leading sensitivity to MCPs but also is extremely sensitive to other forms of exotica beyond the standard model (BSM), such as heavy neutrinos and DM with a large electric dipole moment (EDM). Furthermore, we expect a sizable number of interactions of TeV-energy neutrinos in FORMOSA, providing...
One of the primary aims of the Forward Physics Facility (FPF) would be to search for highly-displaced decays of light and long-lived particles (LLPs) produced in proton-proton collisions at the LHC. These searches are, however, limited to new particles with decay lengths similar to or larger than the baseline of the FPF. We will discuss how this basic constraint can be overcome in models that...
We propose simple freeze-in models where the observed dark matter abundance is explained via the decay of an electrically charged and/or coloured parent particle into Feebly Interacting Massive Particles (FIMP). The parent particle is long-lived and yields a wide variety of LHC signatures depending on its lifetime and quantum numbers. We assess the current constraints and future high...
In the context of a well-motivated gauged U(1) extension of the Standard Model, we introduce a non-thermal dark matter whose interaction is too weak to allow it to be in thermal equilibrium with the Standard Model particles, and its relic density is determined by the freeze-in mechanism through a light mediator that is the extra U(1) gauge boson. We discuss a complementarity between the...
We consider the nonminimal quartic inflation in a classically conformal U(1)$_X$ extended SM. We show that if the inflaton mass and its mixing angle with the SM Higgs field lie in a suitable range, the FASER experiment can search for the inflaton at the High Luminosity (HL)-LHC. Also because of the classical conformal invariance, the inflationary predictions and the LHC search for the U(1)$_X$...
