The aim of our work is to develop plausible theories that address the problems of the Standard Model and to derive signatures, which can be tested at experiments like the Large Hadron Collider at CERN. The central question is the nature of electro-weak symmetry breaking, and the properties of the Higgs particle, which is central to the whole enterprise. The properties of the electroweak symmetry breaking sector remain nebulous, and yet there is no doubt their influence is crucial in many areas of physics such as flavour and CP violation, early Universe cosmology and dark-matter.
Monthly Notices of the Royal Astronomical Society
Abstract: We present the equation of state for two classes of new ultralight particles, a scalar field coupling to electrons and a light ZN QCD axion field coupling to nucleons. Both are potential candidates…
Journal of High Energy Physics
Abstract: We study ultralight scalar fields with quadratic couplings to Standard-Model fermions and derive strong constraints from white-dwarf mass-radius data. Such couplings source scalar profiles inside…
Journal of High Energy Physics
Abstract: The Standard Model extended by a real scalar singlet S with an approximate ℤ2 symmetry offers a minimal framework for realizing electroweak baryogenesis (EWBG) during a first-order electroweak phase…
Physical Review D
Abstract: We identify a new production channel for quantum chromodynamics (QCD) axions in supernova environments that contributes to axion emissivity for all models solving the strong CP problem. This channel…
Journal of High Energy Physics
Abstract: We study how light scalar fields can change the stellar landscape by triggering a new phase of nuclear matter. Scalars coupled to nucleons can develop a non-trivial expectation value at finite baryon…
Journal of High Energy Physics
Abstract: We present a systematic study of QCD axion production in environments with finite baryon density and temperature, implying significant changes to axion phenomenology. Within heavy baryon chiral…
Journal of High Energy Physics
Abstract: We present a systematic study of one-loop quantum corrections in scalar effective field theories from a geometric viewpoint, emphasizing the role of field-space curvature and its renormalisation. By…
SciPost Physics
Abstract: We explore the sensitivity of future hadron colliders to constrain the fermionic Higgs portal, with a focus on scenarios where the new fermions cannot be directly observed in exotic Higgs decays. This…
Physical Review D
Abstract: We study the effects of exceptionally light QCD axions on the stellar configuration of white dwarfs. At finite baryon density, the nonderivative coupling of the axion to nucleons displaces the axion…
SciPost Physics
Abstract: We consider matter density effects in theories with a false ground state. Large and dense systems, such as stars, can destabilize a metastable minimum and allow for the formation of bubbles of the…