CP Violation Beyond the Standard Model - phys.hawaii.edusolsen/pub/krakow/nir_0408hanoi.pdf · CP...
Transcript of CP Violation Beyond the Standard Model - phys.hawaii.edusolsen/pub/krakow/nir_0408hanoi.pdf · CP...
CP Violation Beyond the Standard Model
5th Recontres du VietnamHanoi – August 7, 2004
Yossi Nir (Weizmann Institute of Science)
Thanks to:
• Sandrine Laplace, Zoltan Ligeti
CPV BSM 1/21
Motivation
Why do theorists like CP violation?
1. The study of CPV is experiment-driven.
2. CP is a symmetry of the strong interactions∗
=⇒ Various CP asymmetries can be cleanly interpreted.
3. Almost any model of NP gives new sources of CPV;
In particular, CPV probes the mechanism of supersymmetry
breaking.
4. Baryogenesis implies that there must exist sources of CPV
beyond the KM phase.
∗ θQCD is irrelevant in meson decays
CPV BSM 2/21
Plan of Talk
Plan of Talk
1. CP asymmetries
2. s→ uud: K → ππ (ε and ε′)
3. b→ ccs: B → ψK
4. b→ sss: B → φK, η′K, KKK
5. Supersymmetry
CPV BSM 3/21
CP Asymmetries
P 0 fCP
P 0
A1
A2
M∗12
Γ∗12
A1
A2
CPV BSM 4/21
CP Asymmetries
P 0 fCP
P 0
A1
A2
M∗12
Γ∗12
A1
A2
1
2 1
3
1 Decay |A/A| 6= 1 AA= A1+A2
A1+A2Re ε′ P± → f±
2 Mixing |q/p| 6= 1 qp=
2M∗12−iΓ
∗12
∆M−i∆Γ Re ε P 0, P 0 → `±X
3 Interference Imλ 6= 0 λ =M∗
12
|M12|AA
SψKSP 0, P 0 → fCP
CPV BSM 4/21
CP asymmetries
Direct vs. Indirect CPV
• Indirect CPV
– Can be accounted for by a phase in M12 only
– |q/p| 6= 1 and/or a single Sf ≡ Imλf 6= 0
– Superweak models: only indirect CPV
• Direct CPV
– cannot be accounted for by a phase in M12 only
– |A/A| 6= 1 and/or Sf1 6= Sf2
– SM: possibly large direct CPV
CPV BSM 5/21
Results and Implications: s→ uud
K → ππ
K0ππ
K0
Re ε′
Re ε
Im ε
|ε| = (2.284± 0.014)× 10−3(
ε = 1−λ01+λ0
)
Christenson, Cronin, Fitch, Turlay (64)
Re ε′/ε = (1.67± 0.26)× 10−3(
ε′ = 16 (λ00 − λ+−)
)
NA31 (88), KTeV (01), NA48 (02)
CPV BSM 6/21
Results and Implications: s→ uud
Lessons from ε
• CP violation has been observed.
• Old new physics: a third generation is required.
• A useful CKM constraint: the KM phase is large.
• The NP CP/flavor problem.
CPV BSM 7/21
CP/Flavor problems
The NP CP/Flavor Problem
• m2H ∼ (m2
H)tree +1
16π2Λ2NP
To avoid fine-tuning of the Higgs mass,
ΛNP ∼< 4πmW ∼ 1 TeV .
• LNP ∼1
Λ2NPsdsd
To avoid too large contributions to εK and to ∆mK,D,B ,
ΛNP ∼> 103−4 TeV .
New Physics at the TeV scale must have a
very non-generic flavor and CP structure
CPV BSM 8/21
Results and Implications: s→ uud
Lessons from ε′/ε
• Direct CP violation has been observed.
• The result is consistent with the SM predictions.
• Large hadronic uncertainties =⇒ no useful CKM constraint.
• The superweak scenario is excluded.Wolfenstein (64)
• New physics (e.g. Supersymmetry) may contribute significantly.e.g. Masiero and Murayama (99)
CPV BSM 9/21
Results and Implications: b→ ccs
B0 ψKS
B0
Carter and Sanda (80)
Bigi and Sanda (81)
• Within SM, dominated by a single phase =⇒ CψKS= 0
(Subleading phase CKM- and loop-suppressed)
• Within SM, M∗12 ∝ (V ∗tbVtd)
2, A ∝ V ∗cbVcd =⇒ SψKS= sin 2β
• With NP, still SψKS' sin[arg(M∗
12)− 2 arg(V ∗cbVcd)] and
CψKS' 0, but SψKS
6= sin 2β is possible.
• BABAR and BELLE measure
mode CP SψKS CψKS
ψKS − +0.74± 0.05 0.02± 0.04
CPV BSM 10/21
Results and Implications
Unitarity Triangles
-1
0
1
-1 0 1 2
∆md
∆ms & ∆md
|Vub/Vcb|
ρ
η
CK Mf i t t e r
p a c k a g e
Tree level + CPC observables
∆mB , ∆mBs
Using CKMFitter package (Hocker et al., Eur. Phys. J. C21, 225 (01))
CPV BSM 11/21
Results and Implications
Unitarity Triangles
-1
0
1
-1 0 1 2
∆md
∆ms & ∆md
|Vub/Vcb|
ρ
η
CK Mf i t t e r
p a c k a g e
Tree level + CPC observables
∆mB , ∆mBs
-1
0
1
-1 0 1 2
sin 2βWA
εK
εK
|Vub/Vcb|
ρη
CK Mf i t t e r
p a c k a g e
Tree level + CPV observables
ε, SψKS
Using CKMFitter package (Hocker et al., Eur. Phys. J. C21, 225 (01))
CPV BSM 11/21
Results and Implications: b→ ccs
Lessons from SψK
• CPV in B decays has been observed.
• The Kobayashi-Maskawa mechanism of CPV has successfully
passed its first precision test.
• A significant constraint on the CKM parameters (ρ, η):
ImλψKS= sin 2β = 2η(1−ρ)
η2+(1−ρ)2 = 0.74± 0.05
• Approximate CP (in the sense that all CPV phases are small)
is excluded.
• New, CPV physics that contributes > 20% to B0 −B0 mixing
is disfavored.
CPV BSM 12/21
Results and Implications: b→ ccs
The KM mechanism
• The KM mechanism successfully passed its first precision test
Very likely, the KM mechanism is the dominant
source of CP violation in flavor changing processes
CPV BSM 13/21
Results and Implications: b→ ccs
The KM mechanism
• The KM mechanism successfully passed its first precision test
Very likely, the KM mechanism is the dominant
source of CP violation in flavor changing processes
• ‘Very likely’: The consistency could be accidental
=⇒ More measurements of CPV are crucial.
• ‘Dominant’: There is still room for NP at the O(20%) level
=⇒ A challenge for theorists.
• ‘FC processes’: FD CPV can still be dominated by NP
=⇒ Search for EDMs.
CPV BSM 13/21
Results and Implications
B0 fCP
B0
C
S
fCP b→ qqq′ SM −ηCPS = ± 2Imλ1+|λ|2
C = 1−|λ|2
1+|λ|2
ψKS b→ ccs sin 2β +0.74± 0.05 +0.02± 0.04
φKS b→ sss sin 2β +0.02± 0.67 +0.09± 0.23
η′KS b→ sss sin 2β +0.27± 0.21 +0.04± 0.13
K+K−KS b→ sss sin 2β +0.54± 0.18 +0.07± 0.13
π0KS b→ uus sin 2βeff +0.48± 0.40 +0.40± 0.30
D∗+D∗− b→ ccd sin 2βeff −0.05± 0.31 +0.25± 0.19
ψπ0 b→ ccd sin 2βeff +0.43± 0.38 +0.13± 0.24
π+π− b→ uud sin 2αeff +0.70± 0.31 −0.42± 0.20
ρ+ρ− b→ uud sin 2αeff +0.42± 0.44 −0.17± 0.30
CPV BSM 14/21
b→ sss
B0 φKS , η′KS ,KKK
B0
C
S
• Within SM, dominated by a single phase =⇒ C ≈ 0
(Subleading phase CKM-suppressed)
• Within SM, A ∝ V ∗cbVcd =⇒ S ≈ SψKS(≈ +0.74)
• With NP, S 6= SψKS, Sf1 6= Sf2 and C 6= 0 are possible.
mode CP −ηCPS C
φKS − +0.02± 0.29(0.67)† +0.09± 0.23
η′KS − +0.27± 0.21 +0.04± 0.13
K+K−KS +∗ +0.54± 0.18 +0.07± 0.13
†Babar: +0.47 ± 0.34 ± 0.07; Belle: −0.96 ± 0.50 ± 0.10
∗Isospin analysis is used to argue CP = + dominance.
CPV BSM 15/21
CP/Flavor problems
A SM CP/Flavor Problem?
• CP asymmetries in b→ sss: Sη′KS, SφKS
• Polarization in B → φK∗: fσ ≡|Aσ|
2
|A0|2+|A‖|2+|A⊥|2
– Theoretically (HQE),
(f‖ + f⊥)/f0 = O(1/m2B), f⊥/f‖ = 1 +O(1/mB).
– Experimentally, f0(ρ0K∗+) = 0.96± 0.16,
f0(ρ0ρ+) = 0.96± 0.07, f0(ρ
+ρ−) = 0.99± 0.08
but f0(φK∗0) = 0.58± 0.10, f⊥(φK
∗0) = 0.41± 0.11,
f0(φK∗+) = 0.46± 0.12.
• The lipkin sum rule: RL ≡ 2 Γ(B+→K+π0)+Γ(B0→K0π0)Γ(B+→K0π+)+Γ(B0→K+π−)
– Theoretically (isospin),
RL = 1 +O(
PEW+TP
)2= 1 +O(10−2)
– Experimentally, RL = 1.24± 0.10.
CPV BSM 16/21
CP/Flavor problems
A SM CP/Flavor Problem – Not Yet...
• Sη′KS= 0.27± 0.21:
∼ 2σ.
• SφKS= +0.02± 0.67:
Experimental situation needs to be resolved.
• f0(φK∗0) = 0.58± 0.10, f⊥(φK
∗0) = 0.41± 0.11:
Charming penguins (SCET) / Annihilation diagrams (QCDF)
can account for the data.
• RL = 1.24± 0.10:
∼ 2.4σ
More theoretical effort is needed to determine T/P
CPV BSM 17/21
Supersymmetry
Supersymmetry for Phenomenologists
FV CPV
Y + +
µ − +
A + +
mg − +
m2f
+ +
B − +
80 real + 44 imaginary parameters
CPV BSM 18/21
Supersymmetry
CP Violation in Supersymmetry
• K physics: ImMSUSY12
ImMexp12
∼ 106(
1 TeVm
)2(
∆m212
m2
)2
Im[
(Kd12)
2]
– Heavy squarks: m > 1 TeV ;
– Universality: ∆m221 ¿ m2;
– Alignment: |Kd12| ¿ 1;
– (Approximate CP: sinφ¿ 1)
• B physics: SexpψK ' SSMψK
– consistent with exact universality,
– constrains U(2) and U(1) models, disfavors heavy squarks.
• D physics: x, y ∼< 0.05
– probes alignment.
• EDMs:dSUSYN
6.3×10−26 e cm∼ 300
(
100 GeVm
)2sinφA,B
– can distinguish MFV (∼< 10−31) from SUSY CPV (∼
> 10−28).
CPV BSM 19/21
Supersymmetry
SUSY contributions to B → φKS
b sbR sR
s
s
sR(δd23)RR
• Could there be large effects in B → φKS and not in B → ψKS?
CPV BSM 20/21
Supersymmetry
SUSY contributions to B → φKS
b sbR sR
s
s
sR(δd23)RR
• Could there be large effects in B → φKS and not in B → ψKS?
• Yes: δd23 ↔ δd13
• Could there be large effects in B → φKS and not in B → Xsγ?
CPV BSM 20/21
Supersymmetry
SUSY contributions to B → φKS
b sbR sR
s
s
sR(δd23)RR
• Could there be large effects in B → φKS and not in B → ψKS?
• Yes: δd23 ↔ δd13
• Could there be large effects in B → φKS and not in B → Xsγ?
• Yes: δdRR ↔ δdLR
• Are there well-motivated models with (δd23)RR = O(1)?
CPV BSM 20/21
Supersymmetry
SUSY contributions to B → φKS
b sbR sR
s
s
sR(δd23)RR
• Could there be large effects in B → φKS and not in B → ψKS?
• Yes: δd23 ↔ δd13
• Could there be large effects in B → φKS and not in B → Xsγ?
• Yes: δdRR ↔ δdLR
• Are there well-motivated models with (δd23)RR = O(1)?
• U(1) flavor symmetry: (δd23)RR ∼ (ms/mb)/|Vcb|
• SO(10) GUTs: (δd23)RR ∼ θ`23
CPV BSM 20/21
Conclusions
Conclusions
• The KM mechanism is, very likely, the dominant source of the
CP violation observed in meson decays
• CPV observed (≥ 3σ from Babar+Belle) in three modes:
SψKS= 0.74± 0.05, SK+K−KS
= −0.54± 0.18,
AK∓π± = −0.114± 0.024 (direct CPV!)
• No evidence for new flavor/CP physics
• ∼ 2σ effect in Sη′KS
• “∼ 2.5σ” effect in SD∗+D∗−
• We left the era of hoping for NP altenratives to KM;
We are in the era of seeking for NP corrections to KM
• The field is experiment-driven
Waiting for new results from Belle/Babar/TeVatron
CPV BSM 21/21
Conclusions
Unitarity Triangles 2004
-1.5
-1
-0.5
0
0.5
1
1.5
-1 -0.5 0 0.5 1 1.5 2
K+ → π+νν
|Vub/Vcb|
εK
εK
α
βγ
ρ
η
excluded area has CL < 0.05
C K Mf i t t e r
-1.5
-1
-0.5
0
0.5
1
1.5
-1 -0.5 0 0.5 1 1.5 2
sin 2β
B → ρρ
B → ρρ
∆md
|Vub/Vcb|
sin 2β
α
βγ
ρ
η
excluded area has CL < 0.05
C K Mf i t t e r
-1.5
-1
-0.5
0
0.5
1
1.5
-1 -0.5 0 0.5 1 1.5 2
sin 2β
∆ms & ∆md
|Vub/Vcb|
sin 2β
α
βγ
ρ
η
excluded area has CL < 0.05
C K Mf i t t e r
s→ d
ε, B(K+ → π+νν)
b→ d
∆mBd , SψK , Sρρ
b→ s
∆mBs , SφK,η′K,KKK
There is still a lot to be learnt from future measurements
Laplace (04)
CPV BSM 22/21
Conclusions
Unitarity Triangles 2002
-1
0
1
-1 0 1 2
K+ → π+νν
εK
εK
|Vub/Vcb|
ρ
η
CK Mf i t t e r
p a c k a g e
-1
0
1
-1 0 1 2
sin 2βJ/ΨKs
∆md
|Vub/Vcb|
ρ
ηCK M
f i t t e rp a c k a g e
-1
0
1
-1 0 1 2
sin 2βΦKs
∆ms & ∆md
|Vub/Vcb|
ρ
η
CK Mf i t t e r
p a c k a g e
s→ d
ε, B(K+ → π+νν)
b→ d
∆mBd , SψKS
b→ s
∆mBs , SφKS
There is still a lot to be learnt from future measurements
Laplace (02)
CPV BSM 23/21
CP asymmetries
The case theorists love
B0 fCP
B0
A
M12 A
SfCP
1. Decay dominated by a single CPV phase: |A/A| = 1
2. CPV in mixing negligible: |q/p| = 1
3. The only remaining effect is
AfCP(t)=SfCP sin(∆mB t)
SfCP = ImλfCP = ± sin[arg(M∗12) + arg(AfCP)− arg(AfCP)]
CPV BSM 24/21