Historical clue formulations

• Particle accelerator byproduct — 2025-09-27
• One of many produced in a particle accelerator — 2023-07-15
• Quark/antiquark particle — 2010-12-26
• Quark/antiquark particle — 2010-01-17
• Elementary particle — 2008-12-28
• Quark-antiquark combo — 2006-05-20
• Quark-plus-antiquark particle — 2006-02-12
• Fundamental physics particle — 2004-11-28
• Quark plus antiquark — 2004-04-22
• Physics particle — 2004-01-08
• Quark-plus-antiquark particle — 2003-12-21
• Particle in a quark model — 2002-06-22
• Elementary particle — 2002-03-06
• Quantum physics particle — 2002-02-10
• Subatomic particle — 2001-07-01
• Subatomic particle — 2000-06-02
• A quark and an antiquark — 1998-07-07