1. Elementary Particles Chapter 14
~ Harris Chapter 11;
Rohlf: “Modern Physics from a to Zo”
Particle Adventure at

2. Outline Fundamental Objects 14.1, 14.3, 14.5
Fundamental Interactions 14.2
Odd Topics & Strange Goings-On 14.7

3. Fundamental Objects leptons quarks 3 generations 3 families 6 flavors
all spin ½ objects
0.511 MeV
< 2 eV
105 MeV
< 0.17 MeV
1784 MeV
< 18.2 MeV
~350 MeV
~700 MeV
1500 MeV
~500 MeV
MeV
4700 MeV

4. Fundamental Objects leptons quarks Binding energy is a major effect
3 generations
3 families
6 flavors
leptons
3 generations
3 families
6 flavors
quarks
Binding energy is a major effect
proton = uud = = 1400 >> true mass 938 MeV

5. Fundamental Objects leptons quarks all spin ½ objects
3 generations
3 families
6 flavors
leptons
3 generations
3 families
6 flavors
quarks
all spin ½ objects
Electric charge of leptons
Electric charge of quarks

6. Fundamental Objects 8 gluons --- --- (graviton) Field particles or
gauge bosons
8 gluons
(graviton)
---
---
< 6E-17 eV
80, 91 GeV
other
required
objects
Higgs
bosons LR
bosons
> 114 GeV
> 715 GeV

7. Fundamental Interactions

8. 4 Fundamental Interactions
QED – Quantum Electrodynamics
(electromagnetism)
QCD – Quantum Chromodynamics
(strong force)
QFD – Quantum Flavor Dynamics
(weak interaction)
Quantum Gravity

10. Fundamental Interactions
“Charge”
Gauge
boson
“strength”
Coupling
constant
Vertex
function
Range of
influence
QCD
color
RGB
8 gluons g
as ~ 1 G
< 1 fm
QED
electric charge e
Photon
aEM ~ 1/137 Ze ∞
QFD
flavor
I.V.B.
W± Zo
aWI ~ 10-5 gw
~ 10-3 fm
(gravity)
mass
(graviton)
agrav ~ 10-39 --
a = (vertex fn)2

11. Comments on Fundamental Interactions
Range
photons are ‘stable’  DE = 0  cDt = ∞
IVB are ‘unstable’  DE ~ 2 GeV  cDt ~ 0.1 cm
gluons – no info
Electric Charge
all quarks and e m t and W± can participate in QED
since g has no charge, g cannot interact with g ‘s.
Color
only quarks & gluons have color  participate in QCD
Since g has color, g can interact with g‘s  “glueballs”
Flavor
all quarks and leptons have “flavor”, therefore can participate in QFD

12. Composite Objects Hadrons . mesons – qq baryons – qqq
quaterions – not observed
pentaquarks – i.d.i. .

14. QED
Stationary States
Reactions

15. QED - Stationary States
Some kind
of experiment
to excite the system e p

17. Note: even though we have quessed a good potential function,
we realize that we will have to include s-o, rel KE, Darwin,
Lamb shift, and the perturbations could have been big.

18. Feynmann Diagrams g e+ g e- e- e- time e+ e- e+ e+ g g e- e+ e- e-
arrows are added to help identify particles versus antiparticles e+ e- e+ e+ g g e- e+ e- e-

19. e- e+ m- e+ g g e- e+ e- m+ u e+ c e+ g g e- e-

20. QCD
Stationary States
Reactions

21. QCD - Stationary States

23. K1 ~ 50 MeVfm K2 ~ 1000 MeV/fm ? ? confinement term ‘Coulomb’ term
As a matter of fact, must have V  0 by about 1 fm.

24. RUBBER BANDS U = ½ k (Dx)2 QUARK PAIRS 2 ends 4 ends stretch stretch
& break
stretch
2 ends
U = ½ k (Dx)2
4 ends
QUARK PAIRS
stretch
& break the color field
stretch

26. How-To: quark-quark reactions
meson ?
meson ?
spectator quarks
Which pairs of quarks interacted?

27. uG uR dR dG uR uG

28. dR dG
q = uds... uR uG
Because aQCD > 1, higher order diagrams more important,
can’t use perturbation theory.
must use another
technique to do calcs
“string theory”
“QCD is non-renormalizable.” (in this form)

29. QFD
Stationary States
Reactions

30. QFD – Stationary States
need neutral & colorless system
bound system of neutrinos
not experimentally feasible
excited states of leptons
e* not observed below 90 GeV (1990)
would imply lepton compositeness
 must learn about QFD from reactions

31. QFD - Reactions Experimentally; gw = 1.7 !!!Zo e- e+
Experimentally; gw = !!!
QFD is considered “weak” only because Zo, W± are massive !

32. g e+ g e- e- e- e+ e- e+ e+ g g e- e+ e- e-
arrows are added to help identify particles versus antiparticles e+ e- e+ e+ g g e- e+ e- e-

33. QFD – charged current W+ d u W- W- v u e d e W- (-1/3) (2/3) (0) (2/3)
(-1) d
(-1/3) e W-

34. Zo
QFD – neutral current u
(2/3) u Zo
(2/3) e e e e+ Zo Zo

35. QFD – “flavor changing neutral currents”Zo
QFD – “flavor changing neutral currents” u
(2/3) c
(2/3) Zo Zo d
(-1/3) s
(-1/3)
NOT OBSERVED – or at least very rare

36. neutrino experiments ? ? W- d u
(-1/3)
(2/3)

37. neutrino experiments e v W- e+ d u W+ u d
(-1/3)
(2/3) W+
v only interact with neg quarks u d
(2/3)
(-1/3)
…converse…

39. Strange Goings-On CPT CKM & MNS Matrix Unification
Parity Violation
Regeneration of the kaons
Time Reversal Violation
CKM & MNS Matrix
Quark mixing
Neutrino Mass-Mixing, a.k.a Neutrino Oscillations
Unification
Electroweak Interaction

41. Quark Mixing CKM matrix Cabibbo-Kobayashi-Maskawa matrix
are QCD or ‘mass’ eigenstates W- W- W- u ve vm m- d e-
We have already talked about some great mysteries in physics involving the neutral kaons and the complications arising because of two states of the same mass.
In the early days when people were starting to be successful describing the weak interaction, another great mystery arose.
Reactions involving the top row of diagrams all occurred at the same rate, but the bottom diagram was much weaker. This s-u problem was most evident in the decay of the charged kaons.
Cabibbo proposed that there was a mixing between the mass eigenstates of the d & s quarks. W- u s

42. Quark Mixing CKM matrix Cabibbo-Kobayashi-Maskawa matrix

43. Quark Mixing CKM matrix
are QCD or ‘mass’ eigenstates
In the presence of the weak interaction the states are perturbed
1. d’ s’ b’ are the QFD or weak interaction eigenstates.
The square of an element can be interpreted as the probability that one quark turns into another.
These values are the magnitudes of the matrix elements. The m-e can be complex and it’s now understood that the complex phase angles are responsible for the CP violation problem we discussed earlier.
Because this matrix is unitary, there are actually only 4 parameters required.
Use of the CKM matrix has been very successful in predicting the decay behavior of the b and t quarks.
weak
eigenstates

44. Quark Mixing CKM matrixb s
Weak eigenstates d
probability

45. Analogy: Coupled Pendulum Oscillators

46. Neutral Kaon System: Regeneration
Collision regions
(QCD) WI
eigenstates
QCD
eigenstates
QCD
eigenstates

47. If quark mixing, why not…?

48. Solar Neutrino Problem
MSW Effect
WI eigenstates
Mass eigenstates
Lots of electrons
vacuum
100,000 gal of cleaning fluid
Search for individual Ar atoms
Observed on 1/3 of what expected
About 1967.

49. Neutrino Oscillations
Solar Neutrino Expts (KE ~ 1 MeV)
Homestake Mine, SD (Ray Davis)
Explanation w/i previously existing physics with proper calculation (MSW effect)
MSW effect: ve propagate through dense electrons in Sun
Atmospheric (KE ~ 1 GeV) (vacuum oscill)
Super Kamiokande
Improper ratio of vm to ve events.
Reactor Based (KE ~ 1 MeV) (vacuum oscill)
KamLAND, 53 reactors, anti-ve from fission product decay .
Event rate and energy spectrum
Energy spectrum inconsistent with ‘no oscillation’
Accelerator Based (KE > 3 GeV) (vacuum oscill)
FermiLab vs Los Alamos
CERN & SanGrasso

50. Neutrino Oscillations MNS matrix Maki-Nakagawa-Sakata matrix
q12 ~ 34o
q13 < 13o
q23 ~ 45o
d = ?
Mass eigenstates
WI eigenstates

51. Neutrino Oscillations
Weak eigenstates
probability

52. Analogy: Coupled Pendulum Oscillators

53. Starting with an Electron Neutrino
sin22θ13 = 0.10 (If it turns out to be much smaller or zero, the small wiggles shown here will be much smaller or non-existent, respectively.)
sin22θ23 = 0.97 (It may turn out to be exactly one.)
sin22θ12 =
δ = 0 (If it is actually large, these probabilities will be somewhat distorted and different for neutrinos and antineutrinos.)
Δm2 12 = 7.59×10−5 eV2.
Δm2 32 ≈ Δm2 13 = 2.32×10−3 eV2.
Normal mass hierarchy.
Electron neutrino oscillations, long range. Here and in the following diagrams black means electron neutrino, blue means muon neutrino and red means tau neutrino.

54. Starting with a Muon Neutrino
San Grasso
laboratory
distance

55. The v>c neutrino experiment in current news started out to measure the conversion of vm  vt