1. The Standard Model

2. BOSON LEPTON MESON BARYON Photon 0 0 Neutrino 0 0 Electron 0 ±1
Muon ±1
Pion ±1/0
Kaon ±1 ±1/0
Proton
Neutron
Lambda
Sigma ±1/0
Xi /0

3. The Eightfold Way Meson Octet
In 1962 – Gell-Mann organizes the “particle zoo” and proposes the underlying quark structure. To account for the patterns seen.
Meson
Octet

4. The Eightfold Way Baryon Octet
In 1962 – Gell-Mann organizes the “particle zoo” and proposes the underlying quark structure. To account for the patterns seen.
Baryon
Octet

5. Particle Men
Murray Gell-Mann and George Zweig proposed independently that mesons and baryons are made up of smaller particles… named QUARKS by Gell-Mann.
Gell-Mann Zweig

6. Quark Flavors Quarks are bound together by the strong force.
Quarks possess color charge: “red” “green” or “blue”
Quarks combine into color neutral groups – “hadrons”
Quarks triplets - “baryons”
Quarks pairs - “mesons” (always one quark and one antiquark)

7. Quark Flavors Quarks are bound together by the strong force.
Quarks possess color charge: “red” “green” or “blue”
Quarks combine into color neutral groups – “hadrons”
Quarks triplets - “baryons”
Quarks pairs - “mesons” (always one quark and one antiquark)

8. Quark Flavors Quarks are bound together by the strong force.
Quarks possess color charge: “red” “green” or “blue”
Quarks combine into color neutral groups – “hadrons”
Quarks triplets - “baryons”
Quarks pairs - “mesons” (always one quark and one antiquark)

9. Quark Flavors Quarks are bound together by the strong force.
Quarks possess color charge: “red” “green” or “blue”
Quarks combine into color neutral groups – “hadrons”
Quarks triplets - “baryons”
Quarks pairs - “mesons” (always one quark and one antiquark)

10. Pions Mass Charge UP QUARK : 1.8 - 3.0 MeV + 2/3
Quark pairs (one quark + one anti-quark).
The weak force causes decay with a lifetime of
2.6 x10-8 seconds for charged pions.
(or 8.4 x10-17 seconds for neutral pions)
Mass Charge
UP QUARK : MeV /3
DOWN QUARK : MeV /3

11. Pions p+ ud po dd po uu p- du
Quark pairs (one quark + one anti-quark).
The weak force causes decay with a lifetime of
2.6 x10-8 seconds for charged pions.
(or 8.4 x10-17 seconds for neutral pions)
p+ ud
po dd
po uu
p- du

12. Baryons p+ uud + 2/3 + 2/3 - 1/3  +1 no udd + 2/3 - 1/3 - 1/3  0
Protons and Neutrons contain three quarks each. The mass and charge of the nucleons come from the quarks.
Mass Charge
UP QUARK : MeV /3
DOWN QUARK : MeV /3
p+ uud + 2/3 + 2/3 - 1/3  +1
no udd + 2/3 - 1/3 - 1/3  0

13. Baryons p+ uud 3 + 3 + 5.3  11.3 MeV no udd 3 + 5.3 + 5.3  13.6 MeV
Protons and Neutrons contain three quarks each. The mass and charge of the nucleons come from the quarks.
Mass Charge
UP QUARK : MeV /3
DOWN QUARK : MeV /3
p+ uud  MeV
no udd  MeV

14. Baryons p+ uud 938 MeV >> 11.3 MeV
Protons and Neutrons contain three quarks each. The mass and charge of the nucleons come from the quarks.
Mass Charge
UP QUARK : MeV /3
DOWN QUARK : MeV /3
p+ uud MeV >> MeV
no udd MeV >> MeV

15. Baryons
Protons and neutrons contain three quarks each. The mass and charge of the nucleons come from the quarks.
p+ uud
no udd
A neutron can turn into a proton during beta decay. This is caused by the weak force.

16. Baryons p+ uud no udd p- uud
Protons and neutrons contain three quarks each. The mass and charge of the nucleons come from the quarks.
p+ uud
no udd
p- uud
A neutron can turn into a proton during beta decay. This is caused by the weak force.

17. Deltas D++ uuu D+ uud Do udd D- ddd
Baryons can exist in short-lived excited states
called delta-particles.
The strong force causes decay with a lifetime of
5.6 x10-24 seconds.
D++ uuu
D+ uud
Do udd
D- ddd

18. Quark Theory - Recap D++ uuu D+ uud Do udd D- ddd p+ ud po dd po uu
Quarks – Fundamental particles in existence since the Big Bang.
Possess color charge (R G B)
Hadrons – Subatomic particles composed of quarks.
Are color neutral.
Baryons – Quark triplets ( protons and neutrons are most common ).
Mesons – Quark-antiquark pairs ( pions are most common ).
Deltas – Excited states of hadrons.
D++ uuu
D+ uud
Do udd
D- ddd
p+ ud
po dd
po uu
p- du
p+ uud
no udd

19. Strange Matter Mass Charge Strangeness UP : 3.0 MeV + 2/3 0
K-mesons (or Kaons) were the first “strange” particles
discovered.
The slow decay was caused by a quantum property called
“strangeness”.
Strangeness is possessed by a third quark flavor – “s”
Mass Charge Strangeness
UP : MeV /3 0
DOWN : MeV /
STRANGE : MeV /

20. Strange Matter K+ us Probable Decay Routes Ko ds K+  m+ + nmo
K-mesons (or Kaons) were the first “strange” particles
discovered.
The slow decay was caused by a quantum property called
“strangeness”.
Strangeness is possessed by a third quark flavor – “s”
K+ us Probable Decay Routes
Ko ds K+  m nmo
K+  p po
ho ss K+  p p p-

21. Strange Matter Mesons Baryons K+ us Lo uds Xo uss Ko ds S+ uus X- dss
Heavier “strange” baryons (hyperons) were also discovered.
Double-strange and triple-strange particles must lose one
unit of strangeness in each decay.
Mesons Baryons
K+ us Lo uds Xo uss
Ko ds S+ uus X- dss
So uds
ho ss S- dds W- sss

22. The Eightfold Way Baryon Decuplet
In 1962 – Gell-Mann organizes the “particle zoo” and proposes the underlying quark structure. To account for the patterns seen.
Strangeness (-3)
Mass (1672 MeV)
Theorized
Baryon
Decuplet

23. W-
Discovered 1964 Brookhaven, NY

24. W-
Discovered 1964 Brookhaven, NY

25. BOSON LEPTON MESON BARYON Photon 0 0 Neutrino 0 0 Electron 0 ±1
Muon ±1
Pion ±1/0
Kaon ±1 ±1/0
Proton
Neutron
Lambda
Sigma ±1/0
Xi /0

26. BOSON LEPTON HADRONS QUARK MESON BARYON Photon Neutrino Electron MuonUp
Down Pion 0 ±1/0
Strange Kaon 1 ±1/0
Proton
Neutron
Lambda
Sigma 1 ±1/0
Xi /0
Omega

27. Leptons Mass Charge ELECTRON: 0.511 MeV ± 1
Electrons do not contain any
quarks.
Electrons are not affected by the
strong force.
Mass Charge
ELECTRON: MeV ± 1
NEUTRINO: > 1.2 x10-7 MeV 0
MUON: MeV ± 1

28. Leptons Mass Charge ELECTRON: 0.511 MeV ± 1
Electrons do not contain any
quarks.
Electrons are not affected by the
strong force.
Mass Charge
ELECTRON: MeV ± 1
NEUTRINO: > 1.2 x10-7 MeV 0
MUON: MeV ± 1
TAU: MeV ± 1
(Discovered in 1975 by M. Perl - mean lifetime of 3 x10-13 seconds.)

29. BOSON LEPTON HADRONS QUARK MESON BARYON Photon
Neutrino (e, m, t)  exists as three-fold quantum mix
Electron
Muon
Tau
Up Pion 0 ±1/0
Down Kaon 1 ±1/0
Strange
Proton
Neutron
Lambda
Sigma 1 ±1/0
Xi /0
Omega

31. Pions: Production & Decay.m+ p+

32. Strange Matter Mass Charge UP : 3.0 MeV + 2/3 DOWN : 5.3 MeV - 1/3
K-mesons (or Kaons) were the first “strange” particles
discovered.
Mass Charge
UP : MeV /3
DOWN : MeV /3
STRANGE : MeV /3
CHARM : ,097 MeV 0
BOTTOM: ,180 MeV - 1/3
TOP: ,440 MeV + 2/3

34. Neutral Pion: Production & Decay.g K- po g e- p- e-

35. The Positron: Antimatter. . e+