Glossary
Classes of Particles
Index:
Bosons
Gauge Bosons
photon, W, Z
Mesons
pions, kayons
Fermions
Leptons
electron, neutrinos, muon, tauon
Baryons
proton, neutron, etc
Bosons
described by the
Bose-Einstein statistics
,
can be divided into
Gauge Bosons
Mesons
Gauge Bosons
Particle
Mass x c
2
Lifetime
Photon
0.00
infinity
W
82 GeV
?
Z
93 GeV
?
The
W
&
Z
are known as the
intermediate vector bosons
Mesons
hadrons
composed of
quark + antiquark
(subject to the
strong nuclear force
),
do not obey any conservation law
Particle
Mass x c
2
Lifetime
Pions
140 MeV
10
-8
,
10
-16
Kayons
500 MeV
10
-8
,
10
-10
Eta
550 MeV
<10
-18
Rho
770 MeV
10
-24
Phi
1.0 GeV
10
-22
D
1.9 GeV
10
-12
,
10
-13
J/psi
3.1 GeV
10
-20
B
5.3 GeV
10
-12
Upsilon
9.5 GeV
10
-20
Fermions
described by the
Fermi-Dirac statistics
,
can be divided into
Leptons
Baryons
Leptons
from the Greek word meaning
"light"
truely (?) "elemental" particles
(not subject the
strong nuclear force
),
interact via
Gauge bosons
photons
for the
electromagnetic force
intermediate vector bosons
for the
weak force
)
Particle
Mass x c
2
Lifetime
Neutrinos
0 (<7eV for nu
e
)
infinity
Electron
,
Positron
511 keV
infinity
Muon
106 MeV
10
-6
Tauon
1.8 GeV
10
-13
Baryons
from the Greek word meaning
"heavy"
(
hadrons
)
composed of
three quarks
(subject to the
strong nuclear force
),
described by the
Fermi-Dirac statistics
,
obey the
Pauli exclusion principle
Nonstrange baryons
Particle
Mass x c
2
Lifetime
Proton
938 MeV
infinity
Neutron
940 MeV
920
Nonstrange charmed baryons
Particle
Mass x c
2
Lifetime
Lambda
c
2.3 GeV
10
-13
Strangeness-1 baryons
Particle
Mass x c
2
Lifetime
Lambda
1.1 GeV
10
-10
Sigma
1.2 GeV
10
-10
,
<10
-19
Strangeness-2 baryons
Particle
Mass x c
2
Lifetime
Xi
1.3 GeV
10
-10
Strangeness-3 baryons
Particle
Mass x c
2
Lifetime
Omega
-
1.7 GeV
10
-10
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