Exploring correlations between HEFT Higgs couplings κV and κ2V via HH production at e+e- colliders

• Published in: The European physical journal. C, Particles and fields Particles and fields, 2024-05, Vol.84 (5), p.503
• Main Authors: Dávila, J. M., Domenech, D., Herrero, M. J., Morales, R. A.
• Format: Article
• Language: English
• Subjects: Astronomy; Astrophysics and Cosmology; Bosons; Correlation; Couplings; Elementary Particles; Field theory; Hadrons; Heavy Ions; Higgs bosons; Kinematics; Measurement Science and Instrumentation; Neutrinos; Nuclear Energy; Nuclear Physics; Parameter identification; Parameter sensitivity; Particle decay; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quarks; Regular Article - Theoretical Physics; Sensitivity enhancement; Standard model (particle physics); String Theory
• ISSN: 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-024-12815-5

In this work we explore the phenomenological implications at future e + e - colliders of assuming anomalous couplings of the Higgs boson to gauge bosons HVV and HHVV ( V = W , Z ) given by the κ -modifiers with respect to the Standard Model couplings, κ V and κ 2 V , respectively. For this study we use the Higgs Effective Field Theory (HEFT) where these two κ parameters are identified with the two most relevant effective couplings at leading order, concretely a = κ V and b = κ 2 V . Our focus is put on these two couplings and their potential correlations which we believe carry interesting information on the underlying ultraviolet theory. The particular studied process is e + e - → H H ν ν ¯ , where the vector boson scattering subprocess W W → H H plays a central role, specially at the largest planned energy colliders. Our detailed study of this process as a function of the energy and the angular variables indicates that the produced Higgs bosons in the BSM scenarios will have in general a high transversality as compared to the SM case if κ V 2 ≠ κ 2 V . In order to enhance the sensitivity to these HEFT parameters κ V and κ 2 V and their potential correlations we propose here some selected differential cross sections for the e + e - → H H ν ν ¯ process, where different kinematic properties of the BSM case with respect to the SM are manifested. Finally, we will focus on the dominant Higgs decays to b b ¯ pairs leading to final events with 4 b -jets and missing transverse energy from the undetected neutrinos and will provide the expected accessibility to the ( κ V , κ 2 V ) effective couplings and their potential correlations. In our study we will consider the three projected energies for e + e - colliders of 500 GeV, 1000 GeV and 3000 GeV.