Physics:Bottom eta meson

Bottom eta meson (η_b)

Composition	bb
Statistics	Bosonic
Interactions	Strong, weak, electromagnetic, gravity
Symbol	ηb
antiparticle	Self
Discovered	SLAC (2008)
Types	1
Mass	9388.9+3.1 −2.3 MeV/c2
electric charge	0 e
Spin	0
Isospin	0
Hypercharge	0
Parity	-1
C parity	+1

The bottom eta meson (η_b) or eta-b meson is a flavourless meson formed from a bottom quark and its antiparticle. It was first observed by the BaBar experiment at SLAC in 2008, and is the lightest particle containing a bottom and anti-bottom quark.

See also

• Eta and eta prime mesons, a similar particle with light quarks.
• Quarkonium, the general name for mesons formed from a quark and the corresponding antiquark.
• List of mesons

References

1. Aubert, B. (2008). "Observation of the Bottomonium Ground State in the Decay ϒ(3S)→γη_b". Physical Review Letters 101 (7): 071801. doi:10.1103/PhysRevLett.101.071801. PMID 18764521. Bibcode: 2008PhRvL.101g1801A. 
2. Godfrey, S. (2008). "Searching high and low for bottomonium". Physics 1: 11. doi:10.1103/Physics.1.11. Bibcode: 2008PhyOJ...1...11G. http://physics.aps.org/articles/v1/11.