T meson

T mesons are hypothetical mesons composed of a top quark and one additional subatomic particle. The second subatomic particle can be either an up antiquark (T⁰
), down antiquark (T⁺
), strange antiquark (T⁺
_s), charm antiquark (T⁰
_c) or bottom antiquark (T⁺
_b).^[1] Because of the top quark's short lifetime, T mesons are not expected to be found in nature.^[2]

T meson

Composition	T0 : tu T+ : td T+ s: ts T0 c: tc T+ b: tb
Statistics	bosonic
Family	meson
Interactions	strong, weak, gravitational, electromagnetic
Status	hypothetical
Symbol	T0 , T+ , T+ s, T0 c, T+ b
Antiparticle	T0 : T0 T+ : T− T+ s: T− s T0 c: T0 c T− b: T+ b
Electric charge	T0 , T0 c: 0 e T+ , T+ s, T+ b: +1 e
Topness	+1
Isospin	0

The combination of a top quark and top antiquark is not an open T meson, but rather a closed top-quark meson called toponium. Each T meson has an antiparticle that is composed of a top antiquark and an up (T⁰
), down (T⁻
), strange (T⁻
_s), charm quark (T⁰
_c) or bottom quark (T⁻
_b) respectively.