Exotic hadrons: tetraquarks and pentaquarks
Hadrones exóticos: tetraquarks y pentaquarks
- Date
- 2015 · confidence high
- Place
- CERN, Geneva, Switzerland (LHCb experiment)
- Credited to
- LHCb Collaboration (CERN); Belle (KEK)
- Field
- Cosmos & Earth
What was discovered
LHCb observes in 2015 states formed by five quarks (pentaquarks) and confirms tetraquarks such as the X(3872) found by Belle in 2003, and in 2021 a doubly charmed tetraquark. Quark configurations exist beyond conventional mesons and baryons.
A pentaquark announced in 2003 (LEPS, Japan) turned out to be spurious; those of 2015 have a significance above 9 sigma.
What it led to
- Spectroscopy of exotic hadrons
- Understanding of confinement and hadronic molecules
- LHCb and Belle II programme
Built on
- The quark model1964
- Asymptotic freedom and quantum chromodynamics (QCD)1973
- QCD
- High-precision vertex detectors