What is a tetraquark?
A tetraquark is any particle composed of four quarks and antiquarks – usually two quarks and two antiquarks.
Tetraquarks do not occur naturally anywhere on Earth. For many years, they were merely hypothetical particles [1], but in the 2000s and 2010s, they were created in a number of different particle colliders.
Tetraquarks are highly unstable, and decay in a very short time into other particles.
Names for other particles made of quarks
| Name | Number of Quarks | Status |
|---|---|---|
| diquark | 2 | confirmed – most mesons are diquarks |
| triquark | 3 | confirmed – most baryons are triquarks |
| tetraquark | 4 | confirmed |
| pentaquark | 5 | confirmed |
| hexaquark | 6 | hypothetical |
| heptaquark | 7 | hypothetical |
| octoquark | 8 | hypothetical |
| enneaquark | 9 | hypothetical |
| decaquark | 10 | hypothetical |
References
- ^ Observation of a strange pentaquark, a doubly charged tetraquark and its neutral partner, Large Hadron Collider Beauty Experiment. https://lhcb-outreach.web.cern.ch/2022/07/05/observation-of-a-strange-pentaquark-a-doubly-charged-tetraquark-and-its-neutral-partner/