Scientists find unique particle signature that could reveal dark matter's true nature
Physicists have identified a rare decay pattern at the world's most powerful particle collider that could definitively prove a leading dark matter theory. The signature is impossible to replicate with existing models, giving researchers a concrete way to test whether dark matter comes from a new class of Higgs particles—with major implications for fundamental physics and technology development.
Originaltitel: A smoking gun signature of the 3HDM
<p>We analyse new signals of a 3-Higgs Doublet Model (3HDM) at the Large Hadron Collider (LHC) where only one doublet acquires a Vacuum Expectation Value (VEV), preserving a Z2 parity. The other two doublets are inert and do not develop a VEV, leading to a dark scalar sector controlled by Z2, with the lightest CP-even dark scalar H1 being the Dark Matter (DM) candidate. This leads to the loop induced decay of the next-to-lightest scalar, H2 -> H1 & ell;& ell;<overline>& ell;=e mu\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {H}_2\to {H}_1\ell \overline{\ell}\left(\ell =e,\mu \right) $$\end{document}, mediated by both dark CP-odd neutral and charged scalars. This is a smoking-gun signal of the 3HDM since it is not allowed in the 2-Higgs Doublet Model (2HDM) with one inert doublet and is expected to be important when H2 and H1 are close in mass. In practice, this signature can be observed in the cascade decay of the SM-like Higgs boson, h -> H1H2 -> H1H1 & ell;& ell;<overline>\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ h\to {H}_1{H}_2\to {H}_1{H}_1\ell \overline{\ell} $$\end{document} into two DM particles and di-leptons or h -> H2H2 -> H1H1 & ell;& ell;<overline>& ell;& ell;<overline>\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ h\to {H}_2{H}_2\to {H}_1{H}_1\ell \overline{\ell}\ell \overline{\ell} $$\end{document} into two DM particles and four-leptons, where h is produced from gluon-gluon Fusion. In order to test the feasibility of these channels at the LHC, we devise some benchmarks, compliant with collider, DM and cosmological data, for which the interplay between these production and decay modes is discussed. In particular, we show that the resulting detector signatures, or , with the invariant mass of & ell;& ell;<overline>\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \ell \overline{\ell} $$\end{document} pairs much smaller than mZ, can potentially be extracted already from Run 3 data and at the High-Luminosity phase of the LHC.</p>