List of mesons

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This is a list of mesons; it is not comprehensive.

Particle	Symbol	Anti- particle	Quark Makeup	Spin and parity	Rest mass MeV/c²	S	C	B	Mean lifetime s	Principal decays	Notes
Charged Pion	<math>\mathrm{\pi^+}</math>	<math>\mathrm{\pi^-}</math>	<math>\mathrm{u \bar{d}}</math>	Pseudoscalar	139.6	0	0	0	2.60×10^-8	μ⁺ + ν_μ
Neutral Pion	<math>\mathrm{\pi^0}</math>	Self	<math>\mathrm{\frac{u\bar{u} - d \bar{d}}{\sqrt{2}}}</math>	Pseudoscalar	135.0	0	0	0	0.84×10^-16	2γ	Makeup inexact due to non-zero quark masses
Charged Kaon	<math>\mathrm{K^+}</math>	<math>\mathrm{K^-}</math>	<math>\mathrm{u\bar{s}}</math>	Pseudoscalar	493.7	+1	0	0	1.24×10^-8	μ + ν_μ or π⁺ + π₀
Neutral Kaon	<math>\mathrm{K^0}</math>	<math>\mathrm{\bar{K}^0}</math>	<math>\mathrm{d\bar{s}} </math>	Pseudoscalar	497.7	+1	0	0	weak decay		Strong eigenstate - no definite lifetime (see kaon notes below)
K-Short	<math>\mathrm{K_S^0}</math>	<math>\mathrm{K_S^0}</math>	<math>\mathrm{\frac{d\bar{s} - s\bar{d}}{\sqrt{2}}} </math>	Pseudoscalar	497.7	(*)	0	0	0.89×10^-10	π⁺ + π_- or 2π⁰	Weak eigenstate - makeup is missing small CP-violating term (see kaon notes below)
K-Long	<math>\mathrm{K_L^0}</math>	<math>\mathrm{K_L^0}</math>	<math>\mathrm{\frac{d\bar{s} + s\bar{d}}{\sqrt{2}}}</math>	Pseudoscalar	497.7	(*)	0	0	5.2×10^-8	π⁺ + e^- + ν_e	Weak eigenstate - makeup is missing small CP-violating term (see kaon notes below)
Eta	<math>\mathrm{\eta}</math>	Self	<math>\mathrm{\frac{u\bar{u} + d\bar{d} - 2s\bar{s}}{\sqrt{6}}}</math>	Pseudoscalar	547.8	0	0	0	5×10^-19		Makeup inexact due to non-zero quark masses
Eta Prime	<math>\mathrm{\eta'}</math>	Self	<math>\mathrm{\frac{u\bar{u} + d\bar{d} + s\bar{s}}{\sqrt{3}}}</math>	Pseudoscalar	957.6	0	0	0	3×10^-21		Makeup inexact due to non-zero quark masses
Rho	<math>\mathrm{\rho^+}</math>	<math>\mathrm{\rho^-}</math>	<math>\mathrm{u\bar{d}}</math>	Vector	776	0	0	0	0.4×10^-23
Phi	<math>\mathrm{\phi}</math>	Self	<math>\mathrm{s\bar{s}}</math>	Vector	1019	0	0	0	16×10^-23
D	<math>\mathrm{D^+}</math>	<math>\mathrm{D^-}</math>	<math>\mathrm{c\bar{d}}</math>	Pseudoscalar	1869	0	+1	0	10.6×10^-13
D	<math>\mathrm{D^0}</math>	<math>\mathrm{\bar{D^0}}</math>	<math>\mathrm{c\bar{u}}</math>	Pseudoscalar	1865	0	+1	0	4.1×10^-13
D_s	<math>\mathrm{D_s^+}</math>	<math>\mathrm{D_s^-}</math>	<math>\mathrm{c\bar{s}}</math>	Pseudoscalar	1968	+1	+1	0	4.9×10^-13
J/Psi	<math>\mathrm{J/\psi}</math>	Self	<math>\mathrm{c\bar{c}}</math>	Vector	3096.9	0	0	0	7.2×10^-21	e⁺ + e^- or μ⁺ + μ^- ...	See charmonium
B	<math>\mathrm{B^+}</math>	<math>\mathrm{B^-}</math>	<math>\mathrm{u\bar{b}}</math>	Pseudoscalar	5279	0	0	+1	1.7×10^-12
B	<math>\mathrm{B^0}</math>	<math>\mathrm{\bar{B^0}}</math>	<math>\mathrm{d\bar{b}}</math>	Pseudoscalar	5279	0	0	+1	1.5×10^-12
B_s	<math>\mathrm{B_s^0}</math>	<math>\mathrm{\bar{B}_s^0}</math>	<math>\mathrm{s\bar{b}}</math>	Pseudoscalar	5369	-1	0	+1	1.46×10^-12
B_c	<math>\mathrm{B_c^+}</math>	<math>\mathrm{B_c^-}</math>	<math>\mathrm{c\bar{b}}</math>	Pseudoscalar	6400	0	+1	+1	5×10^-13
Upsilon	<math>\Upsilon\,</math>	Self	<math>\mathrm{b\bar{b}}</math>	Vector	9460	0	0	0	1.3×10^-20	e⁺ + e^- or μ⁺ + μ^- ...	See bottomonium

Image:Noneto mesônico de spin 0.png Image:Noneto mesônico de spin 1.png

[edit] Notes on neutral kaons

There are two complications with neutral kaons:

Due to neutral kaon mixing, the <math>\mathrm{K_S^0}</math> and <math>\mathrm{K_L^0}</math> are not eigenstates of strangeness. However, they are eigenstates of the weak force, which determines how they decay, so these are the particles with definite lifetime.
Furthermore, the linear combinations given in the table for the <math>\mathrm{K_S^0}</math> and <math>\mathrm{K_L^0}</math> are not exactly correct, since there is a small correction due to CP violation. See CP violation in kaons.

Note that these issues also exist in principle for other neutral flavored mesons; however, the weak eigenstates are considered separate particles only for kaons because of their dramatically different lifetimes.