Regarding the Distribution of Glue in the Pion

• 作者: Lei Chang Craig D.Roberts
• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2021,（8）
• 所属期刊栏目: THE PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
• 页码范围: 17-22
• 页数: 6页
• 语种: 英文
• DOI: 10.1088/0256-307X/38/8/081101

摘要

Understanding why the scale of emergent hadron mass is obvious in the proton but hidden in the pion may rest on mapping the distribution functions(DFs)of all partons within the pion and comparing them with those in the proton;and since glue provides binding in quantum chromodynamics,the glue DF could play a special role.Producing reliable predictions for the proton's DFs is difficult because the proton is a three-valence-body bound-state problem.As sketched herein,the situation for the pion,a two-valence-body problem,is much better,with continuum and lattice predictions for the valence-quark and glue DFs in agreement.This beginning of theory alignment is timely because experimental facilities now either in operation or planning promise to realize the longstanding goal of providing pion targets,thereby enabling precision experimental tests of rigorous theory predictions concerning Nature's most fundamental Nambu-Goldstone bosons.