CERN Accelerating science

Preprint
Report number	arXiv:2203.16583
Title	Substructure of Multiquark Hadrons (Snowmass 2021 White Paper)
Author(s)	Brambilla, Nora (Munich, Tech. U. ; TUM-IAS, Munich ; MCQST, Munich) ; Chen, Hua-Xing (Southeast U., Nanjing) ; Esposito, Angelo (Princeton, Inst. Advanced Study) ; Ferretti, Jacopo (Jyvaskyla U.) ; Francis, Anthony (Bern U. ; Taiwan, Natl. Chiao Tung U. ; CERN) ; Guo, Feng-Kun (Beijing, Inst. Theor. Phys. ; Beijing, GUCAS) ; Hanhart, Christoph (Julich, Forschungszentrum) ; Hosaka, Atsushi (Osaka U., Res. Ctr. Nucl. Phys.) ; Jaffe, Robert L. (MIT) ; Karliner, Marek (Tel Aviv U.) ; Lebed, Richard (Arizona State U.) ; Lewis, Randy (York U., Toronto (main)) ; Maiani, Luciano (INFN, Rome) ; Mathur, Nilmani (Tata Inst.) ; Meißner, Ulf-G. (Julich, Forschungszentrum ; Bonn U.) ; Pilloni, Alessandro (Messina U. ; INFN, Messina) ; Polosa, Antonio Davide (INFN, Rome) ; Prelovsek, Sasa (Ljubljana U. ; Stefan Inst., Ljubljana) ; Richard, Jean-Marc (IP2I, Lyon) ; Riquer, Veronica (INFN, Rome) ; Rosina, Mitja (Ljubljana U. ; Stefan Inst., Ljubljana) ; Rosner, Jonathan L. (Chicago U., EFI) ; Santopinto, Elena (INFN, Genoa) ; Swanson, Eric S. (Pittsburgh U.) ; Szczepaniak, Adam P. (Indiana U., Bloomington (main) ; Indiana U. ; Jefferson Lab) ; Takeuchi, Sachiko (Showa Pharmaceutical U.) ; Takizawa, Makoto (Japan Coll. Social Work, Tokyo) ; Wilczek, Frank (Stockholm U. ; MIT ; Tsung-Dao Lee Inst., Shanghai ; Shanghai Jiao Tong U. ; Arizona State U., Tempe) ; Yamaguchi, Yasuhiro (JAERI, Tokai) ; Zou, Bing-Song (Beijing U. of Tech. ; Beijing, GUCAS ; Central South U., Changsha)
Imprint	2022-03-30
Number of pages	47
Note	47 pages, 10 figures. Corresponding authors: Marek Karliner, Elena Santopinto
Presented at	2021 Snowmass Summer Study, Seattle, WA, United States, 11 - 20 July 2021, pp.
Subject category	hep-ph ; Particle Physics - Phenomenology
Abstract	In recent years there has been a rapidly growing body of experimental evidence for existence of exotic, multiquark hadrons, i.e. mesons which contain additional quarks, beyond the usual quark-antiquark pair and baryons which consist of more than three quarks. In all cases with robust evidence they contain at least one heavy quark Q=c or b, the majority including two heavy quarks. Two key theoretical questions have been triggered by these discoveries: (a) how are quarks organized inside these multiquark states -- as compact objects with all quarks within one confinement volume, interacting via color forces, perhaps with an important role played by diquarks, or as deuteron-like hadronic molecules, bound by light-meson exchange? (b) what other multiquark states should we expect? The two questions are tightly intertwined. Each of the interpretations provides a natural explanation of parts of the data, but neither explains all of the data. It is quite possible that both kinds of structures appear in Nature. It may also be the case that certain states are superpositions of the compact and molecular configurations. This Whitepaper brings together contributions from many leading practitioners in the field, representing a wide spectrum of theoretical interpretations. We discuss the importance of future experimental and phenomenological work, which will lead to better understandingof multiquark phenomena in QCD.
Other source	Inspire
Copyright/License	preprint: (License: arXiv nonexclusive-distrib 1.0)