33 research outputs found
Signature of the maximally symmetric 2HDM via W±/Z -quadruplet productions at the LHC
We consider the maximally symmetric two-Higgs doublet model (MS-2HDM) in which the so-called Standard Model (SM) alignment can be achieved naturally by the virtue of an SO(5) symmetry imposed on the 2HDM. We investigate the signature of the MS-2HDM via → HX → VV ∗ X processes at the LHC for different values of tan β. We perform our calculations with next-to-leading-order (NLO) QCD accuracy, using the herwig7 multipurpose event generator at √s = 13 TeV center-of-mass energy. We show that the production of single SM-like Higgs bosons via W±/Z pairs is completely aligned with the SM. Interestingly, the presence of the heavy Higgs states significantly enhances the cross section for the W± /Z- quadruplet production channels in the low -p⊥ regions. These vital analyses may aid the future discovery of this minimal and very predictive extension of the SM and can be generalized to other realizations of the 2HDM
Theory Techniques for Precision Physics -- Snowmass 2021 TF06 Topical Group Report
The wealth of experimental data collected at laboratory experiments suggests
that there is some scale separation between the Standard Model (SM) and
phenomena beyond the SM (BSM). New phenomena can manifest itself as small
corrections to SM predictions, or as signals in processes where the SM
predictions vanish or are exceedingly small. This makes precise calculations of
the SM expectations essential, in order to maximize the sensitivity of current
and forthcoming experiments to BSM physics. This topical group report
highlights some past and forthcoming theory developments critical for
maximizing the sensitivity of the experimental program to understanding Nature
at the shortest distances.Comment: 36 pages, 2 figures. Report of the TF06 topical group for Snowmass
202
The Forward Physics Facility at the High-Luminosity LHC
High energy collisions at the High-Luminosity Large Hadron Collider (LHC) produce a large number of particles along the beam collision axis, outside of the acceptance of existing LHC experiments. The proposed Forward Physics Facility (FPF), to be located several hundred meters from the ATLAS interaction point and shielded by concrete and rock, will host a suite of experiments to probe standard model (SM) processes and search for physics beyond the standard model (BSM). In this report, we review the status of the civil engineering plans and the experiments to explore the diverse physics signals that can be uniquely probed in the forward region. FPF experiments will be sensitive to a broad range of BSM physics through searches for new particle scattering or decay signatures and deviations from SM expectations in high statistics analyses with TeV neutrinos in this low-background environment. High statistics neutrino detection will also provide valuable data for fundamental topics in perturbative and non-perturbative QCD and in weak interactions. Experiments at the FPF will enable synergies between forward particle production at the LHC and astroparticle physics to be exploited. We report here on these physics topics, on infrastructure, detector, and simulation studies, and on future directions to realize the FPF's physics potential
A new phenomenological investigation of KMR and MRW unintegrated parton distribution functions
The forward physics facility at the high-luminosity LHC
High energy collisions at the High-Luminosity Large Hadron Collider (LHC) produce a large number of particles along the beam collision axis, outside of the acceptance of existing LHC experiments. The proposed Forward Physics Facility (FPF), to be located several hundred meters from the ATLAS interaction point and shielded by concrete and rock, will host a suite of experiments to probe standard model (SM) processes and search for physics beyond the standard model (BSM). In this report, we review the status of the civil engineering plans and the experiments to explore the diverse physics signals that can be uniquely probed in the forward region. FPF experiments will be sensitive to a broad range of BSM physics through searches for new particle scattering or decay signatures and deviations from SM expectations in high statistics analyses with TeV neutrinos in this low-background environment. High statistics neutrino detection will also provide valuable data for fundamental topics in perturbative and non-perturbative QCD and in weak interactions. Experiments at the FPF will enable synergies between forward particle production at the LHC and astroparticle physics to be exploited. We report here on these physics topics, on infrastructure, detector, and simulation studies, and on future directions to realize the FPF's physics potential
Maximally symmetric three-Higgs-doublet model
We consider the general three-Higgs-doublet model (3HDM) and identify all limits that lead to exact Standard Model (SM) alignment. After discussing the underlying symmetries that can naturally enforce such an alignment, we focus on the most economic setting, called here the maximally symmetric threeHiggs-doublet model (MS-3HDM). The potential of the MS-3HDM obeys an Sp(6) symmetry, softly broken by bilinear masses and explicitly by hypercharge and Yukawa couplings through renormalizationgroup effects, whilst the theory allows for quartic coupling unification up to the Planck scale. Besides the two ratios of vacuum expectation values, tan β1;2, the MS-3HDM is predominantly governed by only three input parameters; the masses of the two charged Higgs bosons, Mh 1;2 , and their mixing angle σ. Most remarkably, with these input parameters, we obtain definite predictions for the entire scalar mass spectrum of the theory, as well as for the SM-like Higgs-boson couplings to the gauge bosons and fermions. The predicted deviations of these couplings from their SM values might be probed at future precision highenergy colliders. The new phenomenological aspects of the MS-3HDM with respect to the earlier studied maximally symmetric two-Higgs-doublet model are discussed