Eur. Phys. J. C (2024) 84: 1183
https://doi.org/10.1140/epjc/s10052-024-13376-3

Review

HHH whitepaper

¹ Faculty of Sciences and Techniques, Abdelmalek Essaadi University, B.P. 416, Ancienne Route de l’aéroport, Ziaten, Tangier, Morocco
² Stony Brook University, Stony Brook, New York, USA
³ Institute for Theoretical Physics, Karlsruhe Institute of Technology, Wolfgang-Gaede-Str. 1, 76131, Karlsruhe, Germany
⁴ Rudjer Boskovic Institute, Zagreb, Croatia
⁵ University of Oxford, OX1 2JD, Oxford, UK
⁶ Department of Physics, University of California San Diego, 92093, La Jolla, CA, USA
⁷ Nikhef-National Institute for Subatomic Physics, Science Park 105, 1098 XG, Amsterdam, Netherlands
⁸ University of Twente, Drienerlolaan 5, 7522 NB, Enschede, Netherlands
⁹ LPTHE, Physics Department, Faculty of Sciences, Ibnou Zohr University, P.O.B. 8106, Agadir, Morocco
¹⁰ ISEL-Instituto Superior de Engenharia de Lisboa, Instituto Politécnico de Lisboa, 1959-007, Lisbon, Portugal
¹¹ Centro de Física Teórica e Computacional, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Edifício C8, 1749-016, Lisbon, Portugal
¹² Laboratoire de Physique Théorique et Hautes Énergies (LPTHE), UMR 7589, Sorbonne Université et CNRS, 4 Place Jussieu, 75252, Paris Cedex 05, France
¹³ Indian Institute of Technology Kanpur, Kalyanpur, 208016, Kanpur, Uttar Pradesh, India
¹⁴ ICEPP, The University of Tokyo, Hongo, Bunkyo-ku, 113-0033, Tokyo, Japan
¹⁵ Department of Physics, University of Florida, Gainesville, FL, USA
¹⁶ Department of Physics, Brown University, 182 Hope St., 02912, Providence, RI, USA
¹⁷ Department of Physics, Simon Fraser University, V5A 1S6, Burnaby, BC, Canada
¹⁸ School of Science, Shenzhen Campus of Sun Yat-sen University, No. 66 Gongchang Road, Guangming District, 518107, Shenzhen, China
¹⁹ EP Department, CERN, Geneva, Switzerland
²⁰ Department of Physics, Kennesaw State University, 830 Polytechnic Lane, 30060, Marietta, GA, USA
²¹ Department of Physics, Lund University, SE-223 62, Lund, Sweden
²² Université Paris-Saclay, CNRS, CEA, Institut de Physique Théorique, 91191, Gif-sur-Yvette, France
²³ Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
²⁴ Theoretische Physik 1, Center for Particle Physics Siegen (CPPS), Universität Siegen, Walter- Flex-Str. 3, 57068, Siegen, Germany
²⁵ Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405, Orsay, France
²⁶ Institut für Theoretische Physik, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
²⁷ Max-Planck-Institut für Physik, Boltzmannstraße 8, 85748, Garching, Germany
²⁸ Technische Universität München, James-Franck-Strasse 1, 85748, Garching, Germany
²⁹ Department of Physics, University of Wisconsin, 53706, Madison, WI, USA

^a trobens@irb.hr

Received: 26 July 2024
Accepted: 14 September 2024
Published online: 19 November 2024

Abstract

We here report on the progress of the HHH Workshop, that took place in Dubrovnik in July 2023. After the discovery of a particle that complies with the properties of the Higgs boson of the Standard Model, all Standard Model (SM) parameters are in principle determined. However, in order to verify or falsify the model, the full form of the potential has to be determined. This includes the measurement of the triple and quartic scalar couplings.

We here report on ongoing progress of measurements for multi-scalar final states, with an emphasis on three SM-like scalar bosons at 125 $\text{Ge}\text{V}$, but also mentioning other options. We discuss both experimental progress and challenges as well as theoretical studies and models that can enhance such rates with respect to the SM predictions.