1. Lectures on B-physics 19-20 April 2011 Vrije Universiteit Brussel
N. Tuning
Niels Tuning (1)

2. Menu Time Topic Lecture 1 14:00-15:00 C, P, CP and the Standard Model
15:30-16:30
CKM matrix
Lecture 2
10:00-10:45
Flavour mixing in B-decays
11:00-11:45
CP Violation in B-decays
12:00 -12:45
CP Violation in B/K-decays
Lecture 3
14:00-14:45
Unitarity Triangle
15:00-15:45
New Physics?
Niels Tuning (2)

3. Recap uI W dI u W d,s,b Diagonalize Yukawa matrix Yij Mass terms
Quarks rotate
Off diagonal terms in charged current couplings u
d,s,b W
Replace the derivative with the covariant derivative introducing the force carriers: gluons, weak vector bosons and photon.
The constants g_s, g and g’ are the corresponding coupling constants of the gauge particles.
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4. CKM-matrix: where are the phases?
Possibility 1: simply 3 ‘rotations’, and put phase on smallest:
Possibility 2: parameterize according to magnitude, in O(λ): u
d,s,b W
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5. This was theory, now comes experiment
We already saw how the moduli |Vij| are determined
Now we will work towards the measurement of the imaginary part
Parameter: η
Equivalent: angles α, β, γ .
To measure this, we need the formalism of neutral meson oscillations…
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6. Dynamics of Neutral B (or K) mesons…
Time evolution of B0 andB0 can be described by an effective Hamiltonian:
No mixing, no decay…
No mixing, but with decays…
(i.e.: H is not Hermitian!)
With decays included, probability of observing
either B0 or B0 must go down as time goes by:
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7. Describing Mixing…
Time evolution of B0 andB0 can be described by an effective Hamiltonian:
Where to put the mixing term?
Now with mixing – but what is the
difference between M12 and G12?
M12 describes B0  B0 via off-shell states, e.g. the weak box diagram
G12 describes B0fB0 via on-shell states, eg. f=p+p-
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8. Solving the Schrödinger Equation
Eigenvalues:
Mass and lifetime of physical states: mass eigenstates
The physical particles are the eigenstates of the Hamiltonian. Solve the eigenvalues lambda by putting det (H11-lambda*I) = 0
This you can not see here. You just have to sit down and *do* it.
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9. Solving the Schrödinger Equation
Eigenvectors:
mass eigenstates
The physical particles are the eigenstates of the Hamiltonian. Solve the eigenvalues lambda by putting det (H11-lambda*I) = 0
This you can not see here. You just have to sit down and *do* it.
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10. Time evolution
With diagonal Hamiltonian, usual time evolution is obtained:
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11. B Oscillation Amplitudes
For an initially produced B0 or aB0 it then follows: (using:
with
For B0, expect:
DG ~ 0,
|q/p|=1
These formula’s just follow from substitution. No magic. Note that in the last step g_ gets a 90 degree phase !
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12. Measuring B Oscillations
For B0, expect:
DG ~ 0,
|q/p|=1
Examples:
B0B0
Decay probability
Use cos^2 (dmt/2) = 0.5 * (1 + cos(dmt))
Proper Time 
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13. Probability to measure P or P, when we start with 100% P
Compare the mesons:
Probability to measure P or P, when we start with 100% P
P0P0
P0P0
<> Δm
x=Δm/Γ
y=ΔΓ/2Γ K0 s
5.29 ns-1
Δm/ΓS=0.49 ~1 D0 s
0.001 fs-1 ~0
0.01 B0 s
0.507 ps-1
0.78
Bs0 s
17.8 ps-1
12.1
~0.05
Probability 
By the way,
ħ= MeVs
x=Δm/Γ: avg nr of
oscillations before decay
Time 
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14. Summary (1) Start with Schrodinger equation: Find eigenvalue:
Solve eigenstates:
Eigenstates have diagonal Hamiltonian: mass eigenstates!
(2-component state in
P0 and P0 subspace)
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15. Summary (2) Two mass eigenstates Time evolution:
Probability for |P0>  |P0> !
Express in M=mH+mL and Δm=mH-mL  Δm dependence

16. Time dependence (if ΔΓ~0, like for B0):
Let’s summarize …
p, q:
Δm, ΔΓ:
x,y: mixing often quoted in scaled parameters:
q,p,Mij,Γij related through:
Time dependence (if ΔΓ~0, like for B0):
with
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17. Box diagram and Δm Inami and Lim, Prog.Theor.Phys.65:297,1981
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18. Box diagram and Δm
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19. Box diagram and Δm: Inami-Lim
K-mixing
C.Gay, B Mixing, hep-ex/

20. Box diagram and Δm: Inami-Lim
B0-mixing
C.Gay, B Mixing, hep-ex/

21. Box diagram and Δm: Inami-Lim
Bs0-mixing
C.Gay, B Mixing, hep-ex/

22. Next: measurements of oscillations
B0 mixing:
1987: Argus, first
2001: Babar/Belle, precise
Bs0 mixing:
2006: CDF: first
2010: D0: anomalous ??
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23. B0 mixing
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24. B0 mixing
What is the probability to observe a B0/B0 at time t, when it was produced as a B0 at t=0?
Calculate observable probility Y*Y(t)
A simple B0 decay experiment.
Given a source B0 mesons produced in a flavor eigenstate |B0>
You measure the decay time of each meson that decays into a flavor eigenstate (either B0 orB0) you will find that
Exercise idea: compare tau, dm of K0 and B0
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25. B0 mixing: 1987 Argus B0 oscillations: First evidence of heavy top
 mtop>50 GeV
Needed to break GIM cancellations
NB: loops can reveal heavy particles!
Phys.Lett.B192:245,1987
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26. B0 mixing: 2001 B-factories
You can really see this because (amazingly) B0 mixing has same time scale as decay
t=1.54 ps
Dm=0.5 ps-1
50/50 point at pDm  t
Maximal oscillation at 2pDm  2t
Actual measurement of B0/B0 oscillation
Also precision measurement of Dm!
Exercise idea: compare tau, dm of K0 and B0
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27. Bs0 mixing
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28. Bs0 mixing: 2006
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29. Bs0 mixing (Δms): SM Prediction
CKM Matrix
Wolfenstein parameterization
Vts
Ratio of frequencies for B0 and Bs
Vts ~ 2
Vtd ~3  Δms ~ (1/λ2)Δmd ~ 25 Δmd
 = from lattice QCD
-0.035
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30. Bs0 mixing (Δms): Unitarity Triangle
CKM Matrix Unitarity Condition
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31. Bs0 mixing (Δms) cos(Δmst) Proper Time t (ps)
Δms=17.77 ±0.10(stat)±0.07(sys) ps-1
hep-ex/ Bs b b s s t t W
Bs g̃ x b̃ s̃
cos(Δmst)
Proper Time t (ps)
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32. Bs0 mixing (Δms): New: LHCb
LHCb-CONF Bs b b s s t t W
Bs g̃ x b̃ s̃
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33. Mixing  CP violation?
NB: Just mixing is not necessarily CP violation!
However, by studying certain decays with and without mixing, CP violation is observed
Next: Measuring CP violation… Finally
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34. Meson Decays Formalism of meson oscillations: Subsequent: decay
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35. Notation: Define Af and λf
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36. Some algebra for the decay P0  f
Interference
P0 f
P0P0 f
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37. Some algebra for the decay P0  f
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38. The ‘master equations’
(‘direct’) Decay
Interference
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39. The ‘master equations’
(‘direct’) Decay
Interference
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40. Classification of CP Violating effects
CP violation in decay
CP violation in mixing
CP violation in interference
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41. Classification of CP Violating effects - Nr. 3:
Consider f=f :
If one amplitude dominates the decay, then Af = Af
CP violation in interference
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42. Break? What’s the time?
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43. Menu Time Topic Lecture 1 14:00-15:00 C, P, CP and the Standard Model
15:30-16:30
CKM matrix
Lecture 2
10:00-10:45
Flavour mixing in B-decays
11:00-11:45
CP Violation in B-decays
12:00 -12:45
CP Violation in B/K-decays
Lecture 3
14:00-14:45
Unitarity Triangle
15:00-15:45
New Physics?
Niels Tuning (43)

44. Diagonalize Yukawa matrix Yij
Recap Tuesday
Diagonalize Yukawa matrix Yij
Mass terms
Quarks rotate
Off diagonal terms in charged current couplings
Replace the derivative with the covariant derivative introducing the force carriers: gluons, weak vector bosons and photon.
The constants g_s, g and g’ are the corresponding coupling constants of the gauge particles.
Niels Tuning (44) 44

45. The CKM matrix W- b gVub u Couplings of the charged current:
Recap Tuesday
The CKM matrix
Couplings of the charged current:
Wolfenstein parametrization: b W- u
gVub
Magnitude:
Complex phases:
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46. “The” Unitarity triangle
Recap Tuesday
“The” Unitarity triangle
We can visualize the CKM-constraints in (r,h) plane
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47. Neutral Meson Oscillations (1)
Recap Morning
Neutral Meson Oscillations (1)
Start with Schrodinger equation:
Find eigenvalue:
Solve eigenstates:
Eigenstates have diagonal Hamiltonian: mass eigenstates!
(2-component state in
P0 and P0 subspace)
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48. Neutral Meson Oscillations (2)
Recap Morning
Neutral Meson Oscillations (2)
Two mass eigenstates
Time evolution:
Probability for |P0>  |P0> !
Express in M=mH+mL and Δm=mH-mL  Δm dependence

49. Meson Decays Formalism of meson oscillations: Subsequent: decay P0 f
Recap Morning
Meson Decays
Formalism of meson oscillations:
Subsequent: decay
Interference
P0 f
P0P0 f
Interference
(‘direct’) Decay

50. Classification of CP Violating effects
Recap Morning
Classification of CP Violating effects
CP violation in decay
CP violation in mixing
CP violation in interference
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51. Now: Im( λf) CP violation in decay CP violation in mixing
CP violation in interference
We will investigate λf for various final states f

52. CP violation: type 3
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53. |λf|=1 Final state f : J/ΨKs
Interference between B0→fCP and B0→B0→fCP
For example: B0→J/ΨKs and B0→B0→ J/ΨKs
Lets’ s simplify …
For B0 we have:
Since fCP =fCP we have:
The amplitudes |A( B0→J/ψKs)| and |A(B0→J/ψKs)| are equal:
|λf|=1
B0 d B0
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54. Relax: B0J/ΨKs simplifies…
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55. λf for B0 ® J/yK0S c J/y K0 B0 b s d b d s d
|Vcs Vcd|^2 mc^2 = (1*lambda)^2 mc^2 vs. |Vts Vtd|^2 mt^2 = (lambda^2*lambda^3)^2 mt^2  suppressed by lambda^8, enhanced by (mt/mc)^2 << 1 s d
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56. Time-dependent CP asymmetry
λf for B0 ® J/yK0S
Time-dependent CP asymmetry
Theoretically clean way to measure b
Clean experimental signature
Branching fraction: O(10-4)
“Large” compared to other CP modes!
|Vcs Vcd|^2 mc^2 = (1*lambda)^2 mc^2 vs. |Vts Vtd|^2 mt^2 = (lambda^2*lambda^3)^2 mt^2  suppressed by lambda^8, enhanced by (mt/mc)^2 << 1
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57. Remember: C and P eigenvalue
C and P are good symmetries (not involving the weak interaction)
Can associate a conserved value with them (Noether Theorem)
Each hadron has a conserved P and C quantum number
What are the values of the quantum numbers
Evaluate the eigenvalue of the P and C operators on each hadron P|y> = p|y>
What values of C and P are possible for hadrons?
Symmetry operation squared gives unity so eigenvalue squared must be 1
Possible C and P values are +1 and -1.
Meaning of P quantum number
If P=1 then P|y> = +1|y> (wave function symmetric in space) if P=-1 then P|y> = -1 |y> (wave function anti-symmetric in space)
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58. Remember: P eigenvalues for hadrons
The p+ meson
Quark and anti-quark composite: intrinsic P = (1)*(-1) = -1
Orbital ground state  no extra term
P(p+)=-1
The neutron
Three quark composite: intrinsic P = (1)*(1)*(1) = 1
P(n) = +1
The K1(1270)
Quark anti-quark composite: intrinsic P = (1)*(-1) = -1
Orbital excitation with L=1  extra term (-1)1
P(K1) = +1
Meaning: P|p+> = -1|p+>
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59. Intermezzo: CP eigenvalue
Remember:
P2 = 1 (x  -x  x)
C2 = 1 (ψ ψ  ψ )
 CP2 =1
CP | f > =  | f >
Knowing this we can evaluate the effect of CP on the K0
CP|K0> = -1| K0>
CP| K0> = -1|K0 >
CP eigenstates:
|KS> = p| K0> +q|K0>
|KL> = p| K0> - q|K0>
|Ks> (CP=+1) → p p (CP= (-1)(-1)(-1)l= =+1)
|KL> (CP=-1) → p p p (CP = (-1)(-1)(-1)(-1)l=0 = -1)
( S(K)=0  L(ππ)=0 )
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60. CP eigenvalue of final state J/yK0S
CP |J/y> = +1 |J/y>
CP |K0S> = -1 |K0S>
CP |J/yK0S> = -1 |J/yK0S>
( S(J/y)=1 )
( S(B)=0  L(J/yK0S)=0 )
Relative minus-sign between
state and CP-conjugated state:
|Vcs Vcd|^2 mc^2 = (1*lambda)^2 mc^2 vs. |Vts Vtd|^2 mt^2 = (lambda^2*lambda^3)^2 mt^2  suppressed by lambda^8, enhanced by (mt/mc)^2 << 1
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61. Time dependent CP violation
If final state is CP eigenstate then 2 amplitudes (w/o mixing):
B0f and B0B0f
B0 -B0 oscillation is periodic in time  CP violation time dependent
Amplitude 1
Amplitude 2 +
e-iφ
(i=eiπ/2 δ=90o)
(φ=2β)
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62. Time dependent CP violation
If final state is CP eigenstate then 2 amplitudes (w/o mixing):
B0f and B0B0f
B0 -B0 oscillation is periodic in time  CP violation time dependent 1 +
e-iφ
(i=eiπ/2 δ=90o)
(φ=2β)
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63. Sum of 2 amplitudes: sensitivity to phase
What do we know about the relative phases of the diagrams?
B0  f
B0  B0  f
f(strong)=f
Decays are identical
f(strong)=f
K0 mixing exactly cancels Vcs
f(weak)=0
f(weak)=2b
f(mixing)=p/2
There is a phase difference of i between the B0 andB0
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64. Sum of 2 amplitudes: sensitivity to phase
Now also look at CP-conjugate process
Directly observable result (essentially just from counting) measure CKM phase b directly!
N(B0  f)  |A|2  (1-cosf)2+sin2f
= 1 -2cosf+cos2f+sin2f
= 2-2cos(p/2-2b)
 1-sin(2b) + =
Γ(Bf)=
sin(f)
p/2+2b CP
1-cos(f) + =
sin(f)
Γ(Bf)=
p/2-2b
N(B0  f)  (1+cosf)2+sin2f
= 2+2cos(p/2-2b)
 1+sin(2b)
1+cos(f)
Niels Tuning (64)

65. 2 amplitudes 2 phases Remember!
Necessary ingredients for CP violation:
Two (interfering) amplitudes
Phase difference between amplitudes
one CP conserving phase (‘strong’ phase)
one CP violating phase (‘weak’ phase)
2 amplitudes
2 phases
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66. Remember!
2 amplitudes
2 phases
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67. B0→J/ψKs B-system - Time-dependent CP asymmetry BaBar (2002)
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BaBar (2002)

68. Consistency with other measurements in (r,h) plane
4-fold ambiguity because we measure sin(2b), not b
Prices measurement of sin(2β) agrees perfectly with other measurements and CKM model assumptions The CKM model of CP violation experimentally confirmed with high precision! 2 1
without sin(2b) h 3 4 r
Method as in Höcker et al, Eur.Phys.J.C21: ,2001
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69. βs: Bs0 ® J/yφ : Bs0 analogue of B0 ® J/yK0S
Replace spectator quark d  s
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70. βs: Bs0 ® J/yφ : Bs0 analogue of B0 ® J/yK0S
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71. Remember: The “Bs-triangle”: βs
Replace d by s:
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72. βs: Bs0 ® J/yφ : Bs0 analogue of B0 ® J/yK0S
Differences: B0
B0s
CKM
Vtd
Vts ΔΓ ~0
~0.1
Final state (spin)
K0 : s=0
φ: s=1
Final state (K)
K0 mixing -
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73. βs: Bs0 ® J/yφ A║ A┴ A0 B0 B0s CKM Vtd Vts ΔΓ ~0 ~0.1
Vts large, oscilations fast,
need good vertex detector A║ A0 A┴
l=2
l=1
l=0
3 amplitudes B0
B0s
CKM
Vtd
Vts ΔΓ ~0
~0.1
Final state (spin)
K0 : s=0
φ: s=1
Final state (K)
K0 mixing -
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74. “Recent” excitement (5 March 2008)
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75. Bs  J/ψФ : Bs equivalent of B J/ψKs !
The mixing phase (Vtd): φd=2β
B0  f
B0  B0  f
Wolfenstein parametrization to O(λ5):
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76. Bs  J/ψФ : Bs equivalent of B J/ψKs !
The mixing phase (Vts): φs=-2βs
B0  f
B0  B0  f
Vts - s Ф Bs Bs Ф s s s
Vts
Wolfenstein parametrization to O(λ5):
Niels Tuning (76)

77. Bs  J/ψФ : Bs equivalent of B J/ψKs !
The mixing phase (Vts): φs=-2βs
B0  f
B0  B0  f
Vts - s Ф Bs Bs Ф s s s
Vts
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78. Break
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79. Menu Time Topic Lecture 1 14:00-15:00 C, P, CP and the Standard Model
15:30-16:30
CKM matrix
Lecture 2
10:00-10:45
Flavour mixing in B-decays
11:00-11:45
CP Violation in B-decays
12:00 -12:45
CP Violation in B/K-decays
Lecture 3
14:00-14:45
Unitarity Triangle
15:00-15:45
New Physics?
Niels Tuning (79)

80. Next: γ
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81. CKM Angle measurements from Bd,u decays
Sources of phases in Bd,u amplitudes*
The standard techniques for the angles:
bu
Amplitude
Rel. Magnitude
Weak phase
bc
Dominant
bu
Suppressed γ
td (x2, mixing)
Time dependent 2β
*In Wolfenstein phase convention.
td
B0 mixing + single bu decay
B0 mixing + single bc decay
Interfere bc and bu in B± decay.
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82. Determining the angle g
From unitarity we have:
Must interfere b  u (cd) and b c(ud)
Expect b  u (cs) and b c(us) to have the same phase, with more interference (but less events) g l3 l l2 1 l3 1 l2 l
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83. Measure γ: B0s  DsK-/+ : both λf and λf2 +
Γ(Bf)= 2 +
Γ(Bf )=
NB: In addition B s  DsK-/+ : both λ f and λf
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84. Measure γ: Bs  DsK-/+ --- first one f: Ds+K-
This time | Af||Af|, so |λ|1 !
In fact, not only magnitude, but also phase difference:
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85. Measure γ: Bs  DsK-/+ B0s  Ds-K+ has phase difference ( - ):
Need B0s  Ds+K- to disentangle  and :
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86. Kaons… Different notation: confusing! Smaller CP violating effects
But historically important!
Concepts same as in B-system, so you have a chance to understand…
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87. Neutral kaons – 60 years of history
1947 : First K0 observation in cloud chamber (“V particle”)
1955 : Introduction of Strangeness (Gell-Mann & Nishijima)
K0,K0 are two distinct particles (Gell-Mann & Pais)
1956 : Parity violation observation of long lived KL (BNL Cosmotron)
1960 : Dm = mL-mS measured from regeneration
1964 : Discovery of CP violation (Cronin & Fitch)
1970 : Suppression of FCNC, KLmm - GIM mechanism/charm hypothesis
1972 : 6-quark model; CP violation explained in SM (Kobayashi & Maskawa)
: K0,K0 time evolution, decays, asymmetries (CPLear)
: Direct CP violation measured: e’/e ≠ 0 (KTeV and NA48)
… the θ0 must be considered as a "particle mixture" exhibiting two distinct lifetimes, that each lifetime is associated with a different set of decay modes, and that no more than half of all θ0's undergo the familiar decay into two pions.
Niels Tuning (87)
From G.Capon

88. Intermezzo: CP eigenvalue
Remember:
P2 = 1 (x  -x  x)
C2 = 1 (ψ ψ  ψ )
 CP2 =1
CP | f > =  | f >
Knowing this we can evaluate the effect of CP on the K0
CP|K0> = -1| K0>
CP| K0> = -1|K0 >
CP eigenstates (almost):
|KS> = p| K0> +q|K0>
|KL> = p| K0> - q|K0>
|Ks> (CP=+1) → p p (CP= (-1)(-1)(-1)l= =+1)
|KL> (CP=-1) → p p p (CP = (-1)(-1)(-1)(-1)l=0 = -1)
( S(K)=0  L(ππ)=0 )
Niels Tuning (88) 88

89. Decays of neutral kaons
Neutral kaons is the lightest strange particle  it must decay through the weak interaction
If weak force conserves CP then
decay products of K1 can only be a CP=+1 state, i.e. |K1> (CP=+1) → p p (CP= (-1)(-1)(-1)l= =+1)
decay products of K2 can only be a CP=-1 state, i.e. |K2> (CP=-1) → p p p (CP = (-1)(-1)(-1)(-1)l=0 = -1)
You can use neutral kaons to precisely test that the weak force preserves CP (or not)
If you (somehow) have a pure CP=-1 K2 state and you observe it decaying into 2 pions (with CP=+1) then you know that the weak decay violates CP…
( S(K)=0  L(ππ)=0 )
Niels Tuning (89) 89

90. Designing a CP violation experiment
How do you obtain a pure ‘beam’ of K2 particles?
It turns out that you can do that through clever use of kinematics
Exploit that decay of K into two pions is much faster than decay of K into three pions
Related to fact that energy of pions are large in 2-body decay
t1 = 0.89 x sec
t2 = 5.2 x 10-8 sec (~600 times larger!)
Beam of neutral Kaons automatically becomes beam of |K2> as all |K1> decay very early on…
K1 decay early (into pp)
Pure K2 beam after a while! (all decaying into πππ) !
Initial K0 beam
Niels Tuning (90) 90

91. The Cronin & Fitch experiment
Essential idea: Look for (CP violating) K2  pp decays 20 meters away from K0 production point
Decay of K2 into 3 pions
Incoming K2 beam
If you detect two of the three pions of a K2  ppp decay they will generally not point along the beam line
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92. The Cronin & Fitch experiment
Essential idea: Look for K2  pp decays 20 meters away from K0 production point
Decay pions
Incoming K2 beam
If K2 decays into two pions instead of three both the reconstructed direction should be exactly along the beamline (conservation of momentum in K2  pp decay)
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93. The Cronin & Fitch experiment
Essential idea: Look for K2  pp decays 20 meters away from K0 production point
Decay pions
K2  pp decays (CP Violation!)
Incoming K2 beam
K2  ppp decays
Result: an excess of events at Q=0 degrees!
CP violation, because K2 (CP=-1) changed into K1 (CP=+1)
Note scale: 99.99% of K ppp decays are left of plot boundary
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94. Nobel Prize 1980
"for the discovery of violations of fundamental symmetry principles in the decay of neutral K mesons"
The discovery emphasizes, once again, that even almost self evident principles in science cannot be regarded fully valid until they have been critically examined in precise experiments.
James Watson Cronin  
1/2 of the prize  
University of Chicago Chicago, IL, USA
b. 1931
Val Logsdon Fitch  
1/2 of the prize  
Princeton University Princeton, NJ, USA
b. 1923
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95. Cronin & Fitch – Discovery of CP violation
Conclusion: weak decay violates CP (as well as C and P)
But effect is tiny! (~0.05%)
Maximal (100%) violation of P symmetry easily follows from absence of right-handed neutrino, but how would you construct a physics law that violates a symmetry just a tiny little bit?
Results also provides us with convention-free definition of matter vs anti-matter.
If there is no CP violation, the K2 decays in equal amounts to p+ e- ne (a) p- e+ ne (b)
Just like CPV introduces K2  ππ decays, it also introduces a slight asymmetry in the above decays (b) happens more often than (a)
“Positive charge is the charged carried by the lepton preferentially produced in the decay of the long-lived neutral K meson”
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96. Intermezzo: Regeneration
Different cross section for σ(p K0) than σ(pK0)
Elastic scattering: same
Charge exchange : same
Hyperon production: more for K0 !
What happens when KL-beam hits a wall ??
Then admixture changes…: |KL> = p| K0> - q|K0>
Regeneration of KS !
Could fake CP violation due to KS→π+π-…
strong interactions:
must conserve strangeness
leave little free energy – unlikely!
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97. KS and KL KL and KS are not orthogonal:
Usual (historical) notation in kaon physics:
Modern notation used in B physics:
Regardless of notation:
KL and KS are
not orthogonal:
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98. Three ways to break CP; e.g. in K0→ π+π-
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99. Classification of CP Violating effects
CP violation in decay
CP violation in mixing
CP violation in interference
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100. Time evolution
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101. B-system 2. CP violation in mixing K-system
CPLEAR, Phys.Rep. 374(2003)
BaBar, (2002)
CPLear (2003)

102. B-system 2. CP violation in mixing K-system
BaBar, (2002)
NA48, (2001)
L(e) = (3.317   0.072)  10-3
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103. B0→J/ψKs B-system 3.Time-dependent CP asymmetry BaBar (2002)
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BaBar (2002)

104. B0→J/ψKs K0→π-π+ B-system 3.Time-dependent CP asymmetry K-system
~50/50 decay as Ks and KL
+ interference! K0 _ K0
p+p- rate asymmetry
BaBar (2002)
CPLear (PLB 1999)

105. The Quest for Direct CP Violation
Indirect CP violation in the mixing: 
Direct CP violation in the decay: ’
A fascinating 30-year long enterprise: “Is CP violation a peculiarity of kaons? Is it induced by a new superweak interaction?”
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106. B system 1. Direct CP violation K system
B0→K+π-
B0→K-π+
K0→π-π+
K0→π-π+
K0→π0π0
K0→π0π0
Different CP violation for the two decays 
Some CP violation in the decay!
ε’≠ 0
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107. Menu Time Topic Lecture 1 14:00-15:00 C, P, CP and the Standard Model
15:30-16:30
CKM matrix
Lecture 2
10:00-10:45
Flavour mixing in B-decays
11:00-11:45
CP Violation in B-decays
12:00 -12:45
CP Violation in B/K-decays
Lecture 3
14:00-14:45
New Physics?
15:00-15:45
Unitarity Triangle
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