Baryons

ParticleSymbolMakeupRest mass
MeV/c^2
BSLifetime
Decay Modes
Proton
p
uud
938.3
+1
0
Stable
...
Neutron
n
ddu
939.6
+1
0
920
Lambda
uds
1115.6
+1
-1
2.6x10^-10
Sigma
uus
1189.4
+1
-1
0.8x10^-10
Sigma
uds
1192.5
+1
-1
6x10^-20
Sigma
dds
1197.3
+1
-1
1.5x10^-10
Delta
uuu
1232
+1
0
0.6x10^-23
Delta
uud
...
+1
0
0.6x10^-23
Delta
udd
...
+1
0
0.6x10^-23
Delta
ddd
...
+1
0
0.6x10^-23
Xi
uss
1315
+1
-2
2.9x10^-10
Xi
dss
1321
+1
-2
1.64x10^-10
Omega
sss
1672
+1
-3
0.82x10^-10
Lambda
udc
2281
+1
0
2x10^-13
...

As an example of the notation in the column of decay modes, the sigma + decay mode is
written , which implies there are two common decay modes,

Particles which decay by the strong interaction typically do so on a time scale of about 10^-23 seconds, and the baryons listed in the table above have lifetimes on the order of 10^-10 seconds. The reason for those longer lifetimes is that they are forbidden by some kind of conservation law from decaying by the strong interaction, and must decay by the weak interaction. There are dozens of other baryons (i.e., combinations of three quarks), but most of them decay by the strong interaction and are so short lived that they don't leave a measurable track in a bubble chamber or other detection device. These baryons have been detected as "resonances" or peaks in the probability for particle interactions.

Baryon diagramBaryon discussion
Index

Particle concepts

Reference
Serway
Ch. 47

Griffiths
  HyperPhysics***** Quantum Physics

Mesons

ParticleSymbolAnti-
particle
MakeupRest mass
MeV/c^2
SCBLifetime
Decay Modes
Pion
ud
139.6
0
0
0
2.60x10^-8
Pion
Self
135.0
0
0
0
0.83x10^-16
Kaon
us
493.7
+1
0
0
1.24x10^-8
Kaon
1*
497.7
+1
0
0
0.89x10^-10
Kaon
1*
497.7
+1
0
0
5.2x10^-8
Eta
Self
2*
548.8
0
0
0
<10^-18
Rho
ud
770
0
0
0
0.4 x10^-23
Phi
Self
ss
1020
0
0
0
20 x10^-23
D
cd
1869.4
0
+1
0
10.6x10^-13
D
cu
1864.6
0
+1
0
4.2x10^-13
D
cs
1969
+1
+1
0
4.7x10^-13
J/Psi
Self
cc
3096.9
0
0
0
0.8x10^-20
...
B
bu
5279
0
0
-1
1.5x10^-12
B
db
5279
0
0
-1
1.5x10^-12
Upsilon
Self
bb
9460.4
0
0
0
1.3x10^-20
...

1* The neutral Kaons and represent symmetric and antisymmetric mixtures of the quark combinations down-antistrange and antidown-strange.

2* The neutral eta meson is considered to be a quark combination

Meson diagramDiscussion of mesons
Index

Particle concepts

References
Serway
Ch. 47

Giancoli
Ch. 32

Griffiths