Why static bound-state calculations of tetraquarks should be met with scepticism  

作　　者：George Rupp Eef van Beveren 

机构地区：[1]Centro de Fisica e Engenharia de Materiais Avancados, Instituto Superior Tecnico, Universidade de Lisboa, P-1049-001 Lisboa, Portugal [2]Centro de Fisica da UC, Departamento de Fisica, Universidade de Coimbra, P-3004-516 Coimbra, Portugal

出　　处：《Chinese Physics C》2017年第5期49-53,共5页中国物理C（英文版）

摘　　要：Recent experimental signals have led to a revival of tetraquarks,the hypothetical q~2q~2 hadronic states proposed by Jaffe in 1976 to explain the light scalar mesons.Mesonic structures with exotic quantum numbers have indeed been observed recently,though a controversy persists as to whether these are true resonances and not merely kinematical threshold enhancements,or otherwise states not of a true q~2q~2 nature.Moreover,puzzling non-exotic mesons are also often claimed to have a tetraquark configuration.However,the corresponding model calculations are practically always carried out in pure and static bound-state approaches,ignoring completely the coupling to asymptotic two-meson states and unitarity,especially the dynamical effects thereof.In this short paper we argue that these static predictions of real tetraquark masses are highly unreliable and provide little evidence of the very existence of such states.Recent experimental signals have led to a revival of tetraquarks,the hypothetical q^2q^2 hadronic states proposed by Jaffe in 1976 to explain the light scalar mesons.Mesonic structures with exotic quantum numbers have indeed been observed recently,though a controversy persists as to whether these are true resonances and not merely kinematical threshold enhancements,or otherwise states not of a true q^2q^2 nature.Moreover,puzzling non-exotic mesons are also often claimed to have a tetraquark configuration.However,the corresponding model calculations are practically always carried out in pure and static bound-state approaches,ignoring completely the coupling to asymptotic two-meson states and unitarity,especially the dynamical effects thereof.In this short paper we argue that these static predictions of real tetraquark masses are highly unreliable and provide little evidence of the very existence of such states.

关 键 词：meson scalar quark dynamical asymptotic otherwise argue merely decay exotic 

分 类 号：O572.33[理学—粒子物理与原子核物理]