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Observables and anomalies inB→ K(∗)`+`− decaysSam Cunliffe on behalf of the LHCb collaboration. [[email protected]]
Frontiers in Fundamental Physics, Aix Marseille Universite 18th July 2014
Why study rare decays?
The LHCb detector
b→ s`` TheoryThe operator-product expansionObservables, observables, observables
Isospin asymmetry of B→ K(∗)µ+µ−
Angular analysis of B0→ K∗0µ+µ−
Observables from the angular distributionLHCb measurement
InterpretationsGlobal fitsForm factor uncertainties
Lepton universality in B±→ K±`+`−
Something strange from charm
Conclusions
S.Cunliffe (Imperial) FFP14 2/21
Why study rare decays?
I ‘Rare’ Flavour-Changing Neutral Current processesI Forbidden at tree level =⇒ proceed via loops (in SM)
sb
µ−
µ+
W−
Z0, γ
I Searching for new particles via their indirect influence on rare processesI Access to much higher mass scales (particles are virtual)I Able to be model independentI Search for broad classes of new particles at once
I For other flavour observables (and another perspective on b→ s``), see talkby F. Mescia, yesterday
S.Cunliffe (Imperial) FFP14 Why study rare decays? 3/21
Why study rare decays?
I If you want to learn about space...I If you want to find new particles...
χ
χ
q
q
STS-I Launch - NASA/CC [Source]
sb
µ−
µ+
W−
Z0, γ
d d
sb
µ−
µ+
g
H0
d d
d
sb
µ−
µ+
W−
Z ′
d d
sb
µ−
µ+
Z ′
d d
Very Large Array - Image courtesy of NRAO/AUI [Source]
S.Cunliffe (Imperial) FFP14 Why study rare decays? 4/21
Why study rare decays?
I If you want to learn about space...I If you want to find new particles...
χ
χ
q
q
CMS Monojet candidate - [Source]
sb
µ−
µ+
W−
Z0, γ
d d
sb
µ−
µ+
g
H0
d d
d
sb
µ−
µ+
W−
Z ′
d d
sb
µ−
µ+
Z ′
d d
S.Cunliffe (Imperial) FFP14 Why study rare decays? 4/21
Why study rare decays?
I If you want to learn about space...I If you want to find new particles...
χ
χ
q
q
sb
µ−
µ+
W−
Z0, γ
d d
sb
µ−
µ+
g
H0
d d
d
sb
µ−
µ+
W−
Z ′
d d
sb
µ−
µ+
Z ′
d d
S.Cunliffe (Imperial) FFP14 Why study rare decays? 4/21
Why study rare decays?
I If you want to learn about space...I If you want to find new particles...
χ
χ
q
q
sb
µ−
µ+
W−
Z0, γ
d d
sb
µ−
µ+
g
H0
d d
d
sb
µ−
µ+
W−
Z ′
d d
sb
µ−
µ+
Z ′
d d
S.Cunliffe (Imperial) FFP14 Why study rare decays? 4/21
Why study rare decays?
I If you want to learn about space...I If you want to find new particles...
χ
χ
q
q
sb
µ−
µ+
W−
Z0, γ
d d
sb
µ−
µ+
g
H0
d d
d
sb
µ−
µ+
W−
Z ′
d d
sb
µ−
µ+
Z ′
d d
S.Cunliffe (Imperial) FFP14 Why study rare decays? 4/21
Why study rare decays?
I If you want to learn about space...I If you want to find new particles...
χ
χ
q
q
sb
µ−
µ+
W−
Z0, γ
d d
sb
µ−
µ+
g
H0
d d
d
sb
µ−
µ+
W−
Z ′
d d
sb
µ−
µ+
Z ′
d d
S.Cunliffe (Imperial) FFP14 Why study rare decays? 4/21
Why study rare decays?
The LHCb detector
b→ s`` TheoryThe operator-product expansionObservables, observables, observables
Isospin asymmetry of B→ K(∗)µ+µ−
Angular analysis of B0→ K∗0µ+µ−
Observables from the angular distributionLHCb measurement
InterpretationsGlobal fitsForm factor uncertainties
Lepton universality in B±→ K±`+`−
Something strange from charm
Conclusions
The LHCb detectorBeauty Experiment at Small Theta
I Physics reach in other areas than rare b→ s``observables...
I e.g. talks by J. Dalseno on CPV in multibody Bdecaysand B. Couturier on LHCb outreach/education
I 2 < η < 5
I Tracking:0.4 < δp/p < 0.6%
I Vertexing:σIP = 20µm
I Kaon ID = 95%(5% mis-ID)
I Muon ID = 98%(1% mis-ID)
0/4π
/2π/4π3
π
0
/4π
/2π
/4π3
π [rad]1θ
[rad]2θ
1θ
2θ
b
b
z
LHCb MC = 8 TeVs
S.Cunliffe (Imperial) FFP14 The LHCb detector 5/21
Why study rare decays?
The LHCb detector
b→ s`` TheoryThe operator-product expansionObservables, observables, observables
Isospin asymmetry of B→ K(∗)µ+µ−
Angular analysis of B0→ K∗0µ+µ−
Observables from the angular distributionLHCb measurement
InterpretationsGlobal fitsForm factor uncertainties
Lepton universality in B±→ K±`+`−
Something strange from charm
Conclusions
The operator-product expansionOr: how to be model independent
sb
µ−
µ+
W−
Z0, γ
d d
sb
µ−
µ+
W−
W+
νµ
dd
S.Cunliffe (Imperial) FFP14 b→ s`` Theory 6/21
The operator-product expansionOr: how to be model independent
sb
γ
“O7”“C7”
sb
ℓ+
ℓ−“O9”, “O10”“C9”, “C10”
I “Effective operators” OiI “Wilson Coefficients” Ci
I c.f. GF from 4 point β decay modelI Can predict Ci’s for SM and NP scenarios
I Have an effective Hamiltonian =⇒ can calculate things
Heff = −4GF√2
e2
16π2VtbV
∗ts
∑i=7,9,10
(CiOi + C′iO′i
)+ h.c.
S.Cunliffe (Imperial) FFP14 b→ s`` Theory 7/21
The operator-product expansionOr: how to be model independent
sb
γ
“O7”“C7”
sb
ℓ+
ℓ−“O9”, “O10”“C9”, “C10”
I “Effective operators” OiI “Wilson Coefficients” Ci
I c.f. GF from 4 point β decay modelI Can predict Ci’s for SM and NP scenarios
I Have an effective Hamiltonian =⇒ can calculate things
Heff = −4GF√2
e2
16π2VtbV
∗ts
∑i=7,9,10
(CiOi + C′iO′i
)+ h.c.
S.Cunliffe (Imperial) FFP14 b→ s`` Theory 7/21
The operator-product expansionOr: how to be model independent
sb
γ
“O7”“C7”
sb
ℓ+
ℓ−“O9”, “O10”“C9”, “C10”
I “Effective operators” OiI “Wilson Coefficients” Ci
I c.f. GF from 4 point β decay modelI Can predict Ci’s for SM and NP scenarios
I Have an effective Hamiltonian =⇒ can calculate things
Heff = −4GF√2
e2
16π2VtbV
∗ts
∑i=7,9,10
(CiOi + C′iO′i
)+ h.c.
S.Cunliffe (Imperial) FFP14 b→ s`` Theory 7/21
The operator-product expansionOr: how to be model independent
sb
γ
“O7”“C7”
sb
ℓ+
ℓ−“O9”, “O10”“C9”, “C10”
I “Effective operators” OiI “Wilson Coefficients” Ci
I c.f. GF from 4 point β decay modelI Can predict Ci’s for SM and NP scenarios
I Have an effective Hamiltonian =⇒ can calculate things
Heff = −4GF√2
e2
16π2VtbV
∗ts
∑i=7,9,10
(CiOi + C′iO′i
)+ h.c.
S.Cunliffe (Imperial) FFP14 b→ s`` Theory 7/21
A word on QCDEnter form factor uncertainty
I Observables also contain contributions Hadronic Form Factors.I Different theorists use different versions/approximations.
O = f (Ci, {form factors})
sb
µ−
µ+
W−
Z0, γ
d d
S.Cunliffe (Imperial) FFP14 b→ s`` Theory 8/21
A word on QCDEnter form factor uncertainty
I Observables also contain contributions Hadronic Form Factors.I Different theorists use different versions/approximations.
O = f (Ci, {form factors})
sb
µ−
µ+
W−
Z0, γ
d d
sb
µ−
µ+
d d
S.Cunliffe (Imperial) FFP14 b→ s`` Theory 8/21
O7
b→ s``cos θK
q2
V (q2)
T3(q2)
AL⊥
A2(q2)ξ⊥C9
S6
P ′5C7
CNP9
AFB
|AR‖ |2
P ′4
b→ sγ Jc1
ξ‖Js2
Nomenclature
O7
b→ s``cos θK
q2
V (q2)
T3(q2)
AL⊥
A2(q2)ξ⊥C9
S6
P ′5C7
CNP9
AFB
|AR‖ |2
P ′4
b→ sγ Jc1
ξ‖Js2
Nomenclature
q2 = m2``
Squared dileptoninvariant mass
Observables, observables, observables
I Need to find measurable quantities that...I ...are sensitive to the Wilson CoefficientsI ...cancel the QCD uncertainty (hadronic form factors) wherever possible
Lepton-universality
RK =B[B±→ K±µ+µ−
]B[B±→ K±e+e−
]
Isospin asymmetry (spectator-model-asymmetry)
AI =B[B0→ K(∗)0µ+µ−
]− τ
B0
τB+B[B±→ K(∗)±µ+µ−
]B[B0→ K(∗)0µ+µ−
]+
τB0
τB+B[B±→ K(∗)±µ+µ−
]
S.Cunliffe (Imperial) FFP14 b→ s`` Theory 10/21
Why study rare decays?
The LHCb detector
b→ s`` TheoryThe operator-product expansionObservables, observables, observables
Isospin asymmetry of B→ K(∗)µ+µ−
Angular analysis of B0→ K∗0µ+µ−
Observables from the angular distributionLHCb measurement
InterpretationsGlobal fitsForm factor uncertainties
Lepton universality in B±→ K±`+`−
Something strange from charm
Conclusions
Isospin asymmetry of B→ K(∗)µ+µ−
[J. High Energy Phys. 06 (2014) 133]
I Measure asymmetry in ratebetween neutral and chargedmodes
I B0→ K∗0(→ K±π∓)µ+µ−
I B±→ K∗±(→ K0Sπ±)µ+µ−
I B0→ K0Sµ
+µ−
I B±→ K±µ+µ−
I Asymmetry v.close to zero in SMI Experimental challenge:
I K0S → π+π− reconstruction
I Normalise toB→ J/ψ (→ µ+µ−)K(∗)
I 3 fb−1 2011+2012 data
]2c) [MeV/−µ+µ−π+K(m5200 5400 5600
)2 cC
andi
date
s / (
10
MeV
/
0
200
400 LHCb
−µ+µ *0K → 0B
]2c) [MeV/−µ+µ+πS0K(m
5200 5400 5600
)2 cC
andi
date
s / (
10
MeV
/
0
20
40
60
LHCb
−µ+µ *+K → +B
S.Cunliffe (Imperial) FFP14 Isospin asymmetry ofB→ K(∗)µ+µ− 11/21
Isospin asymmetry of B→ K(∗)µ+µ−
AI =B[B0→ K(∗)0µ+µ−
]− τ
B0
τB+B[B±→ K(∗)±µ+µ−
]B[B0→ K(∗)0µ+µ−
]+
τB0
τB+B[B±→ K(∗)±µ+µ−
]
]4c/2 [GeV2q0 5 10 15 20
IA
-1
-0.5
0
0.5
1
LHCb −µ+µ K →B *
]4c/2 [GeV2q0 5 10 15 20
IA
-1
-0.5
0
0.5
1
LHCb −µ+µ K →B
I Consistent with SM. (AI ≈ 0)
S.Cunliffe (Imperial) FFP14 Isospin asymmetry ofB→ K(∗)µ+µ− 12/21
Why study rare decays?
The LHCb detector
b→ s`` TheoryThe operator-product expansionObservables, observables, observables
Isospin asymmetry of B→ K(∗)µ+µ−
Angular analysis of B0→ K∗0µ+µ−
Observables from the angular distributionLHCb measurement
InterpretationsGlobal fitsForm factor uncertainties
Lepton universality in B±→ K±`+`−
Something strange from charm
Conclusions
Observables from the angular distribtionForB0 → K∗(892)0(→ K±π∓)µ+µ− decays...
I P → V V ′ (pseudoscalar to vector-vector)I Vector K∗(892) =⇒ angular distribution, as well as rate, is interesting
B0
K* 0
K+
π - μ -
μ+
θKθℓ
φ
I 3 angles, and q2{θK , θ`, φ, q
2}
I Angular distribution −→ Sets of observables:{FL, AFB, A
2T, S9
} {P ′4, P ′5, P ′6, P ′8}
I ...Clever ratios of angular terms
S.Cunliffe (Imperial) FFP14 Angular analysis ofB0→ K∗0µ+µ− 13/21
Observables from the angular distribtionForB0 → K∗(892)0(→ K±π∓)µ+µ− decays...
I P → V V ′ (pseudoscalar to vector-vector)I Vector K∗(892) =⇒ angular distribution, as well as rate, is interesting
B0
K* 0
K+
π - μ -
μ+
θKθℓ
φ
I 3 angles, and q2{θK , θ`, φ, q
2}
I Angular distribution −→ Sets of observables:{FL, AFB, A
2T, S9
} {P ′4, P ′5, P ′6, P ′8}
I ...Clever ratios of angular terms
S.Cunliffe (Imperial) FFP14 Angular analysis ofB0→ K∗0µ+µ− 13/21
Angular analysis of B0→ K∗0µ+µ−
[Phys. Rev. Lett. 111 (2013) 191801]
I Fit a reduced angular distributionI 3D fit, binned in q2{
P ′4, P′5, P
′6, P
′8
}I Correct for detector acceptance
I Observe local 3.7σ deviationfrom SM [JHEP 1305 (2013) 137]
I Prob. for 24 independentobservations (4P ’s × 6q2 bins) is0.5%
I 1 fb−1 2011 data
]4c/2 [GeV2q0 5 10 15 20
'4
P
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
SM Predictions
Data
LHCb
]4c/2 [GeV2q0 5 10 15 20
'5
P
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
SM Predictions
Data
LHCb
S.Cunliffe (Imperial) FFP14 Angular analysis ofB0→ K∗0µ+µ− 14/21
Why study rare decays?
The LHCb detector
b→ s`` TheoryThe operator-product expansionObservables, observables, observables
Isospin asymmetry of B→ K(∗)µ+µ−
Angular analysis of B0→ K∗0µ+µ−
Observables from the angular distributionLHCb measurement
InterpretationsGlobal fitsForm factor uncertainties
Lepton universality in B±→ K±`+`−
Something strange from charm
Conclusions
Global fitsP ′5 ⇒ tension inC9
Descotes-Genon, Matias & Virto[Phys. Rev. D 88, 074002 (2013)]
I Global fit including {P ′4, P ′5, P ′6, P ′8}I Fit includes b→ s`` and b→ sγ inputsI 4.5σ discrepancy from SM pointI Favours CNP
9 ≈ −1.5
68.3% C.L
95.5% C.L
99.7% C.L
Includes Low Recoil data
Only @1,6D bins
SM
-0.15 -0.10 -0.05 0.00 0.05 0.10 0.15
-4
-2
0
2
4
C7NP
C9N
P
Altmannshofer & Straub[Eur. Phys. J. C (2013) 73: 2646]
I 3σ discrepancyI Differences:
I Definitions of observablesI Different q2 rangesI Theory assumptions
I Best fit is modified C9
I Data described by additional Z′ at ∼ 7TeV
I Hard to reconcile with MSSM-3 -2 -1 0 1 2 3
-3
-2
-1
0
1
2
3
ReHC9NPL
ReHC
9' LFL
S4
S5
AFB
B®K
ΜΜ
S.Cunliffe (Imperial) FFP14 Interpretations 15/21
A hint of new physics?Contributions from new Z′ vector?
Descotes-Genon, et al.[JHEP 1305 (2013) 137)]
I Originally motivated {Pi}observables
I Simplification (assumption) inchoice of form factors
]4c/2 [GeV2q0 5 10 15 20
'5
P
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
SM Predictions
Data
LHCb
3.7σ
Jager & Camlich[JHEP 1305 (2013) 043]
I Uncertainty due to simplifiedchoice of form factors(factorisable corrections areunderestimated)
S.Cunliffe (Imperial) FFP14 Interpretations 16/21
A hint of new physics?...or underestimated errors
Descotes-Genon, et al.[JHEP 1305 (2013) 137)]
I Originally motivated {Pi}observables
I Simplification (assumption) inchoice of form factors
]4c/2 [GeV2q0 5 10 15 20
'5
P
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
SM Predictions
Data
LHCb
3.7σ
Jager & Camlich[JHEP 1305 (2013) 043]
I Uncertainty due to simplifiedchoice of form factors(factorisable corrections areunderestimated)
B0→K*0µµ : interpretation
∃∀
• Global fits → 2-4σ tension
• Views from the theory community:
– P5’ tension correlated with other
(smaller) tensions and NP explanation consistent with all
measurements is possible [1,2]
– Theory errors underestimated,
tension is reduced [3]
• Difficult to explain with SUSY [1]
• Consistent with a Z’ with mass ~ 7 TeV (!) [4]
→ Measure other B→Kµµ decays!
∀%&∋()∗+,#,−.#//01∀
]4c/2 [GeV2q
0 5 10 15 20
'5
P
-1
0
1
SM arXiv:1303.5794
SM arXiv:1212.2263
-1LHCb 1fb
%,1∀2345&66789:;∋∀;4∀&3.<∀&∋()∗+,#−/.,=−,>∀%!1∀?;7≅94;7ΑΒ;696∀;4∀&3.<∀Χ8∆7.∀Ε;∗.∀?∀//<∀−0∃−−!∀Φ!−,#Γ<∀Η9∋Ι&6∀
;4∀&3.<∀&∋()∗+,#,−.#//0>∀%#1∀ϑ;&ΚΛ;&6∀;4∀&3.<∀&∋()∗+,#,−.!∃0/<∀Μ&;Ι;∋∀;4∀&3.<∀&∋()∗+,!,!.!!Ν#>∀%∃1∀Β&Κ3Ο∀;4∀&3.<∀
ΜΗΠΧ∀,∃−,∀Φ!−,∃Γ∀−ΝΘ<∀ϑΚ∋&7∀;4∀&3.<∀&∋()∗+,#,,.Ν0!Θ∀
S.Cunliffe (Imperial) FFP14 Interpretations 16/21
Why study rare decays?
The LHCb detector
b→ s`` TheoryThe operator-product expansionObservables, observables, observables
Isospin asymmetry of B→ K(∗)µ+µ−
Angular analysis of B0→ K∗0µ+µ−
Observables from the angular distributionLHCb measurement
InterpretationsGlobal fitsForm factor uncertainties
Lepton universality in B±→ K±`+`−
Something strange from charm
Conclusions
Lepton universality in B±→ K±`+`−
[arXiv:1406.6482] submitted: Phys.Rev.Lett
RK =B[B±→ K±µ+µ−
]B[B±→ K±e+e−]
I If a Z′ is responsible for P ′5 does itcouple equally to lepton flavours?
I Altmannshofer et al.[Phys. Rev. D89 (2014) 095033]
I Kruger & Hiller[Phys.Rev. D69 (2004) 074020]
I Experimental challenge:I Selection of B±→ K±e+e−
I Bremsstrahlung → q2 movementI Correct for bremsstrahlung with
calorimeter photonsI Migration in q2 corrected with
simulationI 3 fb−1 2011+2012 data
]2c) [MeV/−e+e
+K(m
5000 5200 5400 5600
)2c
Can
did
ate
s /
( 4
0 M
eV
/
0
5
10
310×
LHCb
(a)B±→ J/ψK±
]2c) [MeV/−
e+e+
K(m
5000 5200 5400 5600
)2c
Can
did
ate
s /
( 4
0 M
eV
/
0
10
20
30
40 LHCb
(d)B±→ K±e+e−
S.Cunliffe (Imperial) FFP14 Lepton universality inB±→ K±`+`− 17/21
Lepton universality in B±→ K±`+`−
I Experimentally, use double ratio with B±→ J/ψK± decaysI Cancels systematic biases
RK =NK±µ+µ−
NJ/ψ (µ+µ−)K±
NJ/ψ (e+e−)K±
NK±e+e−×εJ/ψ (µ+µ−)K±
εK±µ+µ−
εK±e+e−
εJ/ψ (e+e−)K±
where Nf is the observed yield for B±→ f and εf is the corresponding efficiency
I RK = 1.000 in SM (argue aboutthe 4th s.f.)
I SM Higgs v.suppressedI LHCb measuresRK = 0.745+0.090
−0.074 ± 0.036
I In range q2 ∈ [1, 6]GeV2/c4
I Only agrees with SM within 2.6σ ]4c/2 [GeV2q0 5 10 15 20
KR
0
0.5
1
1.5
2
SM
LHCbLHCb
LHCb BaBar Belle
BaBar: [Phys. Rev. D86 (2012) 032012]
Belle: [Phys.Rev.Lett. 103 (2009) 171801]
S.Cunliffe (Imperial) FFP14 Lepton universality inB±→ K±`+`− 18/21
Why study rare decays?
The LHCb detector
b→ s`` TheoryThe operator-product expansionObservables, observables, observables
Isospin asymmetry of B→ K(∗)µ+µ−
Angular analysis of B0→ K∗0µ+µ−
Observables from the angular distributionLHCb measurement
InterpretationsGlobal fitsForm factor uncertainties
Lepton universality in B±→ K±`+`−
Something strange from charm
Conclusions
Something strange from charm
3.7 3.8 3.9 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5.0-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
Rexp
Rthe
Rcon
Rint
Rres
RBW
R
Ecm(GeV)
χ2/d.o.f=1.05
BESII e+e−→ hadrons/e+e−→ µ+µ−
0
0.5
1
1.5
2
2.5
3
3.5
3.6 3.8 4 4.2 4.4 4.6
dB
r
d√
q2[B
+→
K+µµ]/
10−
7G
eV−
1
!q2/GeV
Ψ(3770)
Ψ(4040)
Ψ(4160)
Ψ(4400)
a) afacb) ηcafacc) ρr ∈ Rd) ρr ∈ CLHCb
(4415)
(2S)
LHCb data: B±→ K±µ+µ−, L&Z fits
Lyon & Zwicky[arXiv:1406.0566]
I Fit BESII and LHCb dataI Necessary to add in large corrections (fudge factors) to get good fitI Are we underestimating the non-factorisable effects in Ceff
9 ?I Could explain P ′5 effectI And/or motivate new physics studies in b→ ccs operators
S.Cunliffe (Imperial) FFP14 Something strange from charm 19/21
Something strange from charm (loops)
ℓ
cc
O1,2
ℓℓ
γ(q)
b s
(a) (b)ℓ
O1,2
ℓℓ
γ(q)
b s
ℓ
J/Ψ, Ψ′..
O1,2
ℓℓ
γ(q)
b s
ℓ
O1,2
ℓℓ
γ(q)
b s
ℓ
O1,2b s
cc
O1,2b s OG
b sg
ℓℓℓ
γ(q)ℓ ℓ
(c)
I Massively underestimated terms like (a) at low q2
I The green gluons can’t account for this
S.Cunliffe (Imperial) FFP14 Something strange from charm 20/21
Why study rare decays?
The LHCb detector
b→ s`` TheoryThe operator-product expansionObservables, observables, observables
Isospin asymmetry of B→ K(∗)µ+µ−
Angular analysis of B0→ K∗0µ+µ−
Observables from the angular distributionLHCb measurement
InterpretationsGlobal fitsForm factor uncertainties
Lepton universality in B±→ K±`+`−
Something strange from charm
Conclusions
Conclusions
I FCNC processes probe higher mass scales for NPI Formalism gives model-independenceI Observables!
I Interesting results in b→ s`` processesI Isospin asymmetry in B→ K(∗)µ+µ−
I Angular analyses of B0→ K∗0µ+µ−
I Lepton universality in B±→ K±`+`−
I Interest from our theory/phenomenology friends
I LHCb data-taking in 2015...I Belle-II physics runs late 2016...
S.Cunliffe (Imperial) FFP14 Conclusions 21/21
[Backup Slides]
The actual definitions of the Wilson Operators
Heff = −4GF√2
e2
16π2VtbV
∗ts
∑i=7,9,10
(CiOi + C′iO′i
)+ h.c.
O7 =e
g2mb(sσµνPRb)F
µν , O′7 =e
g2mb(sσµνPLb)F
µν ,
O9 =e2
g2(sγµPLb)(¯γµ`), O′9 =
e2
g2(sγµPRb)(¯γµ`),
O10 =e2
g2(sγµPLb)(¯γµγ5`), O′10 =
e2
g2(sγµPRb)(¯γµγ5`),
S.Cunliffe (Imperial) FFP14 Backup 23/21
The actual definitions of the Wilson Operators
Ci = CSMi + CNP
i , C′i = C′ SMi + C′NP
i .
I @ right-handed interactions i = 9, 10 operators in SM
C′ SM9,10 = 0
I ∃ helicity-suppressed right-handed SM contributions to O′7 so
C′7 =ms
mb(CSM
7 + CNP7 ) + C′NP
7 .
S.Cunliffe (Imperial) FFP14 Backup 24/21
Angular distribution of B0→ K∗0µ+µ−
The distribution of for vectorK∗0(892)
d4Γ
d cos θKd cos θldφdq2=
9
32π
(Js1 sin2 θK + Jc1 cos2 θK
+ (Js2 sin2 θK + Jc2 cos2 θK) cos 2θ`
+ J3 sin2 θK sin2 θ` cos 2φ
+ J4 sin 2θK sin 2θ` cosφ
+ J5 sin 2θK sin θ` cosφ
+ J6 sin2 θK cos θ`
+ J7 sin 2θK sin θ` sinφ
+ J8 sin 2θK sin 2θ` sinφ
+ J9 sin2 θK sin2 θ` sin 2φ
)
S.Cunliffe (Imperial) FFP14 Backup 25/21
Angular distribution of B0→ K∗0µ+µ−
The principle moments
J1s =3
4
[|AL⊥|2 + |AL‖ |2 + |AR⊥|2 + |AR‖ |2
]J1c = |AL0 |2 + |AR0 |2
J2s =1
4
[|AL⊥|2 + |AL‖ |2 + |AR⊥|2 + |AR‖ |2
]J2c = −
[|AL0 |2 + |AR0 |2
]J3 =
1
2
[|AL⊥|2 − |AL‖ |2 + |AR⊥|2 − |AR‖ |2
]J4 =
1√2
[<(AL0A
L∗‖ +AR0 A
R∗‖ )]
J5 =√
2[<(AL0A
L∗⊥ −AR0 AR∗⊥ )
]J6 = 2
[<(AL‖A
L∗⊥ −AR‖ AR∗⊥ )
]J7 =
√2[=(AL0A
L∗‖ −AR0 AR∗‖ )
]J8 =
1√2
[=(AL0A
L∗⊥ −AR0 AR∗⊥ )
]J9 = =(AL∗‖ AL⊥ +AR∗‖ AR⊥).
(1)
S.Cunliffe (Imperial) FFP14 Backup 26/21
The AmplitudesCalculated in the effective field theory
AL,R⊥ = N√
2λ1/2
[ [(Ceff
9 + Ceff′9 )∓ (Ceff
10 + Ceff′10 )] V (q2)
mB +mK∗
+2mb
q2(Ceff
7 + Ceff′7 )T1(q2)
],
AL,R‖ = −N√
2(m2B −m2
K∗)
[ [(Ceff
9 − Ceff′9 )∓ (Ceff
10 − Ceff′10 )] A1(q2)
mB −mK∗
+2mb
q2(Ceff
7 − Ceff′7 )T2(q2)
],
AL,R0 = − N
2mK∗∗√q2
{[(Ceff
9 − Ceff′9 )∓ (Ceff
10 − Ceff′10 )]
×[(m2
B −m2K∗∗ − q2)(mB +mK∗∗)A1(q2)− λ A2(q2)
mB +mK∗∗
]+ 2mb(C
eff7 − Ceff′
7 )
[(m2
B + 3m2K∗∗ − q2)T2(q2)− λ
m2B −m2
K∗∗T3(q2)
]},
S.Cunliffe (Imperial) FFP14 Backup 27/21
The AmplitudesCalculated in the effective field theory
...where
N = VtbV∗ts
[G2Fα
2
3 · 210π5m3B
q2λ1/2βµ
]1/2
,
with λ = m4B +m4
K∗ + q4 − 2(m2Bm
2K∗ +m2
K∗q2 +m2
Bq2) and
βµ =√
1− 4m2µ/q2.
S.Cunliffe (Imperial) FFP14 Backup 28/21
What are the Pi observables?
P ′i ≡Si√
FL(1− FL)=
1
2
1
dΓ/dq2
Ji + Ji√FL(1− FL)
P ′5 ≡1
2
1
dΓ/dq2
√2[<(AL0A
L∗⊥ −AR0 AR∗⊥ )
]√FL(1− FL)
I The asymmetry of the cross term between the longitudinal andperpendicularly polarised amplitudes.
S.Cunliffe (Imperial) FFP14 Backup 29/21