WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin...

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WIR SCHAFFEN WISSEN – HEUTE FÜR MORGEN Explaining the Flavour Anomalies with New Physics Andreas Crivellin Theory Group of the Laboratory for Particle Physics Corfu, 05.09.2017

Transcript of WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin...

Page 1: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

WIR SCHAFFEN WISSEN – HEUTE FÜR MORGEN

Explaining the Flavour Anomalieswith New Physics

Andreas CrivellinTheory Group of the Laboratory for Particle Physics

Corfu, 05.09.2017

Page 2: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

• Introduction:

New Physics and Flavour anomalies

− b→sμμ

− b→cτν

− aμ

− Z’ explanations for b→sμμ

• Simultaneous explanations with LQs

• Conclusions

Outline

Page 2Andreas Crivellin

Page 3: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

Dir

ect

se

arc

he

sFlavour observables

Page 3

• At colliders one produces many (up to 1014) heavy quarks

or leptons and measures their decays into light flavours

Finding NP in Flavour Observables

Andreas Crivellin

Flavour observables are sensitive to higher energy scales than collider searches

Experiment

Standard Model

New Physics

Page 4: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

Hints for LFUV

Page 4

Lepton Flavour

Universality Violation

(LFUV)

LFUV

Electron channels:

SM like

b→sµµ5-6σ

R(D(*))

τ→µνν2σ

Andreas Crivellin

Page 5: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

� MSSM

� tan(ß) enhanced slepton loops

� Scalars

� Light scalars with enhanced muon couplings

� Z’

� Very light with τμ couplings (mτ enhancement)

� Leptoquarks

� mt enhaned effects

8

aµ explanations

Chiral enhancement or very light particles

Page 5

e.g. W. Altmannshofer, C. Chen, P.S.B. Dev, A. Soni, arXiv:1607.06832, …

e.g. D. Stockinger, hep-ph/0609168

e.g. A. Djouadi, T. Kohler, M. Spira, J. Tutas, Z.Phys. C46 (1990)

e.g. A. Broggio et at. arXiv:1409.3199 A.C. et al. arXiv:1507.07567

E. Leskow, A.C., G. D'Ambrosio, D. Müller

arXiv:1612.06858

Page 6: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

� Chirally enhanced effects via top-loops

8

Scalar Leptoquarks in aµ

Z→μμ at future colliders

Page 6

E. Leskow, A.C.,

G. D'Ambrosio,

D. Müller

arXiv:1612.06858

,L R

µλ

Left-, right-

handed

muons-top

coupling

Page 7: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

� Charged scalars

� Problems with

q2 distributions

and Bc lifetime

� W’

� Strong constraints

from direct LHC searches

� Leptoquark

� Strong signals in qq→ττ searches

8

R(D) & R(D*)

Large tree-level effect neededExplanation difficult

Page 7

Faroughy et al. arXiv:1609.07138

See talk of Roman

Page 8: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

R(D(*)) and b→sττ (model-independent)

• Large couplings to the second generation needed in

order avoid collider and EW precision bounds

• Cancellation in b→sνν needed: C(1)≈C(3)

Bs→ττ

very strongly

enhanced

LHCb limit

Page 9: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

b→sμμ model-independent analysis

Page 9

• Several 2-3σ deviations in more than 130 observables

− P5’

− R(K)

− R(K*)

− Bs→ϕμμ• 6 NP operators

Modelindependent fit

4-6 σ better than SM

( ) ( )' 5

9 LO s P bµ

µ µγ µγ γ µ=

See talk of Nazila

B. Capdevila, AC, S. Descotes-Genon, J. Matias and J. Virto, arXiv:1704.05340 [hep-ph].

Page 10: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

� Z’

� Leptoquarks

� Loop effects

b→sμμ explanations

Even high scale NP explanations possible

Page 10

U. Haisch et al. 1308.1959, Buras et al. 1311.6729

W. Altmannshofer et al. 1403.1269, AC. et al. 1501.00993, …..

LQ

µ

µb

s

Gudrun Hiller, Martin Schmaltz

arXiv:1411.4773

B. Gripaios, M. Nardecchia, S.A. Renner.

arXiv:1412.1791

D. Bečirević, N. Košnik, O. Sumensari,

R. Zukanovich Funchal, arXiv:1608.07583

L. Calibbi, AC. T. Ota, PRL 2015

B. Gripaios, M. Nardecchia, S. Renner, arXiv:1509.05020

See talk of Stephen King

Page 11: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

R(K), R(K*) and µ→eγ with LQs

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� Three LQs give

a good fit

� Scalar triplet

� Vector singlet

� Vector triplet

� Simultaneous

effect in b→sμμ

and b→see

generate μ→eγ

AC, D. Mueller, A. Signer, Y. Ulrich,

arXiv:1505.xxxx

Page 12: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

New Scalars and Fermions in b→sµµ

� Possible representations

Page 12

2x6x4 possibilitiesPere Arnan, A.C., Lars Hofer and Federico Mescia, arXiv:1608.07832

Page 13: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

Bs mixing

requires

Majorana

Fermions

b→sμμ 3σ

2σ1σ

b→sµµ and Bs mixing

Page 13

Explanation with O(1) couplings

Page 14: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

Implications for New Particles

Page 14

Lepto-quarks

b→sμμR(D(*))

Higgsesaμ

Z’ gauge boson

Extension of the SM is required!

What is the underlying

theory?

Andreas Crivellin

Scalars and

fermions

Page 15: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

Simultaneous Explanation ofR(D), R(D*), aµ

and b→sμμ unsing

Leptoquarks

Page 16: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

Two Scalar Leptoquarks

• scalar leptoquark singlet with Y=-2/3

• scalar leptoquark triplet with Y=-2/3

AC, D. Mueller, T. Ota

arxiv:1703.09226

Constructive in R(D(*))

Destructive in b→sμμ

Page 17: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

R(D(*)), b→sνν with 2 Scalar LQs

1

3

L L

jk jk

L i j L

jk jkeπ

λ λ

λ λ

=

Page 18: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

R(D(*)), b→sμμ and aμ with 2 scalar LQs

• Scalar leptoquark singlet + triplet with Y=-2/3

• Cancelation in b→sνν imposed

2 out of 3 can be explained

Page 19: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

Vector Leptoquark SU(2) Singelet

• C9=-C10 effect in b→sμμ

• Left handed vector current in R(D) and R(D*)

• No effect in b→sνν

• No proton decay

• Contained within the Pati-Salam model

• Massive vector bosons

− Non-renormalizable without Higgs mechanism

− Pati Salam not possible at the Tev scale

because of KL→μe and K→πμe

Good solution, but difficult UV completion

Page 20: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

Pati-Salam + vector-like fermions

L. Calibbi, AC and T. Li, A model of vector leptoquarks in view of the $B$-physics anomaliesarXiv:1709.00692

Page 21: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

Pati-Salam + vector-like fermions

− 3 light generation (SM fermions)

− 3 heavy generation (vector like)

Only the LQ couples flavour violating

( ) ( )Q Q L L

ij iL ij iL jR ij iL ij iL jRL m q M Q Q M L m L′ ′⊃ − + − + ℓ

, ,R L L

R L L

R L Li i i

Q Q qY Y X

L L

′ = = = ′ ℓ

Page 22: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

R(D(*)) and b→sμμ

Simultaneous explanation possible!Can also account for the AMM of the muon

1

Q

ii

QQ iii Q

ii

Q

ii

m

Ms

m

M

=

+

3 3

1

2

1.5

Q Ls s

M TeV

= =

=

Page 23: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

• P5’ b→dμμ

• R(D) & R(D*) b→sττ

• R(K) & R(K*) μ→eγ

• R(D), R(D*) & aμ τ → μγ

• R(D), R(D*) & b → sμμ b → sτμ

Outlook

Page 23Andreas Crivellin

Intersting experimental prospects

NP

Page 24: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

• Intriguing hints for Lepton Flavour Universality

violating New Physics

•Leptoquarks are prime

candidates for a solution

•Confirming or disproving

the anomalies makes

a model selection

•Predictions for flavor

and LHC observables

Conclusions

Page 24Andreas Crivellin

LHC

Dark Matter

Flavour

Exciting times in particle physics are ahead of us!

NP

Page 25: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

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� Lμ-Lτ flavour symmetry

� Flavon couples to μ and τ

� is protected

� is not protected

� Effects in

τ µγ→

h µµ→

W. Altmannshofer, M. Carena, AC, 1604.08221

Lµ-Lτ model for aµ

Page 25

Explanation ofaμ and b→sμμ

Page 26: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

� Avoid vector-like quarks by assigning charges to

baryons as well

� Same mechanism in the quark and lepton sector

� Lμ-Lτ in lepton sector

� Good symmetry for the PMNS matrix

� Effect in but not

� First two quark generations must have the same

charges because the large Cabibbo angle would lead to

huge effect in Kaon mixing

� Anomaly freedom

Solution with horizontal U(1) charges

( ) ( ), ,2Q B a a a= − −Q(L)=(0,1,-1) Q(B)=(a,a,-2a)

9C µµ

9

eeC

Page 26

Page 27: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

∆F=2: Z’ contribution

q

q

q

K

B

B SM

B

K

SM

K

mR

m

ε

ε

∆=

=

Page 27

Necessarily constructive, but Higgs effects and be destructive.

Page 28: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

Symmetry

breaking

Dynamical explanation of the charges

Page 28

A.C., J. Fuentes-Martin, A. Greljo and G. Isidori arXiv:1611.02703

( ) ( ) ( )3 3 3Q U D

SU SU SU× ×

En

erg

ysc

ale

Quark Sector Lepton Sector

( ) ( ) ( )3 3 3RE

SU SU Oν

× ×ℓ

( ) ( ) ( ) ( )2 2 2 1Q U D q

SU SU SU U× × × ( ) ( )2 1E

SU U×ℓ

( )1q

U ( )1Uℓ

Standard Model

Page 29: WIR SCHAFFEN WISSEN –HEUTE FÜR MORGEN Andreas Crivellinpsi_ch_01.pdf · Andreas Crivellin Flavour observables are sensitive to higher energy scales than collider searches Experiment

� 2 Z’ bosons

� Z1 coupling

mainly

to leptons

� Z2 coupling

mainly

to quarks

8

Solution with two Z’s

Different collider signatures

Page 29

Low energy

phenonenology

unchanged