The aim of the LHC Higgs Working Group (LHCHWG) is to collect and produce theoretical predictions relevant for Higgs physics in the Standard Model and beyond. Summaries of these activities have been made available in four CERN Reports: "Inclusive Observables" (CERN-2011-002), "Differential Distributions" (CERN-2012-002), "Higgs Properties" (CERN-2013-004) and "Deciphering the nature of the Higgs Sector" (CERN-2017-002).
We plan to hold the meeting in-person at CERN, but a video connection will be available for those who cannot travel to CERN.
If you will request financial assistance, you must register before October 30th and request it in the registration form.
Zoom connection and Mattermost discussion details will be sent to registered participants ahead of the start of the workshop.
The trilinear Higgs coupling is a crucial tool to determine the structure of the Higgs potential and to probe possible effects of physics beyond the Standard Model (SM). Focusing on a Two-Higgs-Doublet Model as a concrete example, I will discuss the calculation of the dominant two-loop corrections to the trilinear Higgs coupling, and show that this coupling can be significantly enhanced with respect to its SM prediction, in certain regions of parameter space. Taking into account all relevant corrections up to the two-loop level, I will demonstrate that the current experimental bounds on the trilinear coupling already rule out significant parts of the parameter space that would otherwise be unconstrained. Finally, I will present a benchmark scenario illustrating the interpretation of the current results and future measurement prospects.
Based on Bahl, Braathen, Weiglein 2202.03453, accepted for publication in Phys. Rev. Lett.
Double Higgs production will be a key observable to probe the structure of the Higgs potential. In this talk I will present the first step in obtaining the electroweak corrections to double Higgs production by considering the leading Yukawa corrections to this process in the high energy limit. I will describe the methods we used and show that we obtain precise numerical results down to $p_T \approx 100 \,$GeV.
based on JHEP 08 (2022) 259 (arxiv:2207.02587)
In this talk we will discuss the production of three Higgs bosons in the LHC and at a proton-proton collider running at a centre-of-mass energy of 100 TeV. We will argue that the seemingly challenging 6-botton jets final state is a very good candidate to investigate triple Higgs production within and beyond the SM in proton-proton colliders. In particular we will consider three different scenarios: one in which the triple and quartic Higgs boson self-couplings are not affected by new physics phenomena besides the Standard Model (SM) and in addition, we will explore two possible SM extensions by one and two new scalars. We will show that a 100 TeV machine can impose competitive constraints on the quartic coupling in the SM-like scenario. In the case of the scalar extensions of the SM, we will show that large significances can be obtained in the LHC and the 100 TeV collider while obeying current theoretical and experimental constraints including a first order electroweak phase transition.
The dominant Higgs pair production process in the HL-LHC is gluon fusion, which we study in the framework of the Two Higgs Doublet Model. As a key observable we evaluate the invariant mass distribution of two Higgses at 125 GeV in the final state. We analyze in particular the contribution of the resonant diagram involving a heavy CP-even Higgs boson exchange. We analyze the potential sensitivity to the triple Higgs couplings involved. We show that for the benchmark points where the resonant production is dominant, the contribution of different parameters of the extra scalar can be traced. These parameters are its mass, total decay width and relative sign of BSM Higgs trilinear and top Yukawa couplings. Finally, we discuss the effects of experimental uncertainties by applying smearing and binning to the invariant mass.
The Higgs boson pair production via gluon-gluon fusion and vector boson fusion in the bbμ+μ− final state at the LHC is studied to probe the Higgs self-coupling κλ and the four-boson HHVV coupling κ2V for the first time. A cut-based analysis and a machine learning analysis using boosted decision trees are performed with categorizations and optimizations depending on the variations of these couplings. The expected sensitivities are extracted with different luminosities assumed up to the full HL-LHC runs. The expected upper limit at 95% confidence level on the HH production is calculated as 47 (28) times the Standard Model cross-section using the cut-based method (boosted decision trees) for the gluon-gluon fusion production, and 928 for the vector boson fusion production, assuming an integrated luminosity of 3000 fb−1. The expected constraints on the couplings at 95% confidence level are calculated to be −13.8 < κλ < 19.1 (−10.0 < κλ < 15.5) and −3.4 < κ2V < 5.5 using the cut-based method (boosted decision trees), respectively, assuming an integrated luminosity of 3000 fb−1.
https://arxiv.org/abs/2207.10912
The current Simplified Template Cross-Section (STXS) categorization leaves STXS analyses insensitive to CP-odd contributions in Higgs boson production, which are predicted by several models beyond the Standard Model. This presentation proposes to categorize events with two jets additionally via the dPhijj observable to make future Run 2+3 analyses sensitive to CP violation. The feasibility of such a splitting based on our present sensitivity is also discussed