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Nonstandard Yukawa Couplings Joachim Brod Workshop The CP nature of - - PowerPoint PPT Presentation

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Nonstandard Yukawa Couplings Joachim Brod Workshop The CP nature of the Higgs boson Amherst Center for Fundamental Interactions May 2, 2015 Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 1 / 42 Motivation NP at LHC We

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SLIDE 1

Nonstandard Yukawa Couplings

Joachim Brod Workshop “The CP nature of the Higgs boson” Amherst Center for Fundamental Interactions – May 2, 2015

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 1 / 42

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Motivation – NP at LHC

We have found New Physics (NP) at the LHC! ⇒ The Higgs Yet, we still need to find NP beyond the Standard Model (BSM) The discovery of the/a Higgs boson opens a new window to NP BSM CP violation

In the quark sector consistent with SM Already probe scales of up to O(104) TeV CP violation in the Higgs sector?

Interesting for electroweak baryogenesis

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 2 / 42

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SLIDE 3

Motivation – SM Higgs

Higgs couplings completely determined in the SM SM Yukawas are

flavor-diagonal real (CP-conserving)

Experimentally, we know nearly nothing about the light-fermion Yukawas

) µ Signal strength (

1 − 1 2 3

ATLAS Preliminary

  • 1

= 7 TeV, 4.5-4.7 fb s

  • 1

= 8 TeV, 20.3 fb s

= 125.36 GeV

H

m

0.26
  • 0.28
+

= 1.17 µ γ γ → H

0.08
  • 0.12
+ 0.11
  • 0.16
+ 0.23
  • 0.23
+ 0.34
  • 0.40
+

= 1.46 µ ZZ* → H

0.11
  • 0.18
+ 0.13
  • 0.19
+ 0.31
  • 0.35
+ 0.21
  • 0.24
+

= 1.18 µ WW* → H

0.09
  • 0.13
+ 0.14
  • 0.17
+ 0.16
  • 0.16
+ 0.37
  • 0.39
+

= 0.63 µ b b → H

0.07
  • 0.09
+ 0.23
  • 0.24
+ 0.30
  • 0.31
+ 0.37
  • 0.42
+

= 1.44 µ τ τ → H

0.10
  • 0.16
+ 0.23
  • 0.29
+ 0.29
  • 0.30
+ 3.7
  • 3.7
+

= -0.7 µ µ µ → H

0.4
  • 0.4
+ 0.7
  • 0.5
+ 3.6
  • 3.6
+ 4.5
  • 4.6
+

= 2.7 µ γ Z → H

0.3
  • 1.1
+ 1.3
  • 1.7
+ 4.2
  • 4.3
+ 0.14
  • 0.15
+

= 1.18 µ

Combined

0.07
  • 0.08
+ 0.10
  • 0.11
+ 0.10
  • 0.10
+

Total uncertainty µ

  • n

σ 1 ±

(stat.) σ

)

theory sys inc.

(

σ (theory) σ

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 3 / 42

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SLIDE 4

How can we change the Higgs couplings?

Operator Mass term Higgs-fermion coupling yt( ¯ QLtRHc) + h.c. mt = ytv

√ 2 yt √ 2 H†H Λ2 ( ¯

QLtRHc) + h.c. δmt ∝ (v/

√ 2)3 Λ2

δyt ∝ 3 (v/

√ 2)2 Λ2

Mass and Yukawa term become independent Relative complexe phase → CP violation More generally, we write: L′

Y = − yf

√ 2 (κf + i˜ κf ) ¯ fLfRh + h.c.

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 4 / 42

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SLIDE 5

Motivation – baryogenesis

[Huber, Pospelov, Ritz, hep-ph/0610003]

A minimal setup for baryogenesis: L = 1 Λ2 (H†H)3 + Zt Λ2 (H†H) ¯ Q3HctR Λ ∼ 500 − 800 GeV gives correct ηb In principle there are more operators Simple UV completion: Second heavy Higgs doublet Hh Λ ∼ MHh

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 5 / 42

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Motivation – EDM constraints on baryogenesis

[Huber, Pospelov, Ritz, hep-ph/0610003]

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 6 / 42

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SLIDE 7

Outline

CPV Yukawa couplings Light-fermion Yukawas Flavor changing Higgs couplings

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 7 / 42

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SLIDE 8

CP-violating Yukawa couplings

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 8 / 42

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SLIDE 9

From h → γγ . . .

h γ γ t

In the SM, Yukawa coupling to fermion f is LY = − yf √ 2 ¯ f f h We will look at modification L′

Y = − yf

√ 2

  • κf ¯

f f + i˜ κf ¯ f γ5f

  • h

New contributions will modify Higgs production cross section and decay rates

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 9 / 42

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SLIDE 10

. . . to electric dipole moments

h γ γ t f f f

Attaching a light fermion line leads to EDM Indirect constraint on CP-violating Higgs coupling SM “background” enters at three- and four-loop level Complementary to collider measurements Constraints depend on additional assumptions

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 10 / 42

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SLIDE 11

Electric Dipole Moments (EDMs) – Generalities

Energy T eV GeV QCD nuclear atomic

EDMs of para- magnetic atoms and molecules EDMs of diamagnetic atoms neutron EDM Modi ed Higgs couplings Higher-dimensional Higgs e ective operators

[Adapted from Pospelov et al., 2005]

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 11 / 42

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SLIDE 12

CPV in htt couplings

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 12 / 42

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SLIDE 13

Constraints from gg → h

gg → h generated at one loop Have effective potential Veff = −cg αs 12π h v G a

µν G µν,a − ˜

cg αs 8π h v G a

µν

G µν,a

h g b, t g

cg, ˜ cg given in terms of loop functions κg ≡ cg/cg,SM, ˜ κg ≡ 3˜ cg/2cg,SM σ(gg → h) σ(gg → h)SM = |κg|2 + |˜ κg|2 = κ2

t + 2.6 ˜

κ2

t + 0.11 κt (κt − 1)

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 13 / 42

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SLIDE 14

Constraints from h → γγ

h → γγ generated at one loop Have effective potential Veff = −cγ α π h v Fµν F µν − ˜ cγ 3α 2π h v Fµν F µν

h γ γ b, t h γ γ W

cγ, ˜ cγ given in terms of loop functions κγ ≡ cγ/cγ,SM, ˜ κγ ≡ 3˜ cγ/2cγ,SM Γ(h → γγ) Γ(h → γγ)SM = |κγ|2 + |˜ κγ|2 = (1.28 − 0.28 κt)2 + (0.43 ˜ κt)2

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 14 / 42

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SLIDE 15

LHC input

Naive weighted average of ATLAS, CMS κg,WA = 0.91 ± 0.08 , κγ,WA = 1.10 ± 0.11 We set κ2

g/γ,WA = |κg/γ|2 + |˜

κg/γ|2

γ

κ

0.0 0.5 1.0 1.5 2.0

g

κ

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0

CMS Preliminary

  • 1

19.6 fb ≤ = 8 TeV, L s

  • 1

5.1 fb ≤ = 7 TeV, L s g

κ ,

γ

κ

[CMS-PAS-HIG-13-005]

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 15 / 42

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SLIDE 16

Electron EDM

h γ γ t e

EDM induced via “Barr-Zee” diagrams [Weinberg 1989, Barr & Zee 1990] |de/e| < 8.7 × 10−29 cm (90% CL) [ACME 2013] with ThO molecules |˜ κt| < 0.01 Constraint on ˜ κt vanishes if Higgs does not couple to electron

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 16 / 42

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SLIDE 17

Neutron EDM

h γ γ t q h g g t q h g g t g

Three operators; will mix, need to perform RGE analysis dn e =

  • (1.0 ± 0.5)
  • −5.3κq˜

κt + 5.1 · 10−2 κt˜ κt

  • + (22 ± 10) 1.8 · 10−2 κt˜

κt

  • · 10−25 cm .

w ∝ κt˜ κt subdominant |dn/e| < 2.9 × 10−26 cm (90% CL) [Baker et al., 2006]

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 17 / 42

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SLIDE 18

Mercury EDM

h g g t q

Diamagnetic atoms also provide constraints |dHg/e| < 3.1 × 10−29 cm (95% CL) [Griffith et al., 2009] Dominant contribution from CP-odd isovector pion-nucleon interaction dHg e = −

  • 4+8

−2

3.1 ˜ κt − 3.2 · 10−2 κt˜ κt

  • · 10−29 cm

Again, w ∝ κt˜ κt subdominant, but does not vanish if Higgs does not couple to light quarks

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 18 / 42

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SLIDE 19

Other low-energy constraints

b s s b t t h

No effects in dim. six operators

b s t γ h

O(100) effects allowed by data

b s µ+ t W ¯ Bs h µ− t

O(100) effects allowed by data

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 19 / 42

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Combined constraints on top coupling

Assume SM couplings to electron and light quarks Future projection for 3000fb−1 @ high-luminosity LHC

[J. Olsen, talk at Snowmass Energy Frontier workshop]

Factor 90 (300) improvement on electron (neutron) EDM

[Fundamental Physics at the Energy Frontier, arXiv:1205.2671]

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 20 / 42

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SLIDE 21

Combined constraints on top couplings

Set couplings to electron and light quarks to zero Contribution of Weinberg operator will lead to strong constraints in the future scenario

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 21 / 42

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SLIDE 22

CPV in hbb couplings

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 22 / 42

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Collider constraints

Modifications of gg → h, h → γγ due to κb = 1, ˜ κb = 0 are subleading ⇒ Main effect: modifications of branching ratios / total decay rate Br(h → b¯ b) =

  • κ2

b + ˜

κ2

b

  • Br(h → b¯

b)SM 1 +

  • κ2

b + ˜

κ2

b − 1

  • Br(h → b¯

b)SM Br(h → X) = Br(h → X)SM 1 +

  • κ2

b + ˜

κ2

b − 1

  • Br(h → b¯

b)SM Use naive averages of ATLAS / CMS signal strengths ˆ µX for X = b¯ b, τ +τ −, γγ, WW , ZZ ˆ µX = Br(h → X)/Br(h → X)SM

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 23 / 42

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SLIDE 24

RGE analysis of the b-quark contribution to EDMs

EDMs suppressed by small bottom Yukawa ≈ 3 scale uncertainty in CEDM Wilson coefficient Two-step matching at Mh and mb:

h g g b q

Integrate out Higgs Oq

1 = ¯

qq ¯ biγ5b Mixing into

Oq

4 = ¯

qσµνT aq ¯ biσµνγ5T ab

Matching onto

Oq

6 = − i 2 mb gs ¯

qσµνT aγ5qG a

µν Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 24 / 42

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SLIDE 25

RGE analysis of the b-quark contribution to EDMs

h γ γ b q

Cq

5(µb) = −4 ααs (4π)2 Qq log2 m2

b

M2

h +

αs

4π

3 γ(0)

14 γ(0) 48 γ(0) 87

48

log3 m2

b

M2

h + O(α4

s) ,

Cq

6(µb) =

αs

4π

2 γ(0)

14 γ(0) 48

8

log2 m2

b

M2

h + O(α3

s) ,

C7(µb) = αs

4π

2 γ(1)

5,11

2

log m2

b

M2

h + O(α3

s) .

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 25 / 42

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SLIDE 26

Combined constraints on bottom couplings

Assume SM couplings to electron and light quarks Future projection for 3000fb−1 @ high-luminosity LHC Factor 90 (300) improvement on electron (neutron) EDM

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 26 / 42

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SLIDE 27

Combined constraints on bottom couplings

Set couplings to electron and light quarks to zero Contribution of Weinberg operator will lead to competitive constraints in the future scenario

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 27 / 42

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CPV in hττ couplings

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 28 / 42

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SLIDE 29

Combined constraints on τ couplings

Effect of modified hττ coupling on κγ, ˜ κγ again subleading Get simple constraint from modification of branching ratios Shaded region shows reach for direct searches

[Harnik et al., Phys.Rev. D88 (2013) 7, 076009 [arXiv:1308.1094[hep-ph]]]

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 29 / 42

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SLIDE 30

CPV in light-fermion Yukawas

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 30 / 42

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Electron Yukawa

γ, Z h γ t e e e γ, Z h γ W e e e h γ W e e e νe W

. . . + 117 more two-loop diagrams Complete analytic result [Altmannshofer, Brod, Schmaltz, arxiv:1503.04830] |de/e| < 8.7 × 10−29 cm (90% CL) [ACME 2013] . . . leads to |˜ κe| < 0.017

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 31 / 42

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SLIDE 32

Light-quark Yukawas

h γ W e e e νe W h γ W u u u d, s, b W h γ W d d d u, c, t W

In principle have all ingredients for light quarks: Combine complete analytic two-loop result and RGE evolution |de/e| < 8.7 × 10−29 cm (90% CL) [ACME 2013] . . . leads to |˜ κq| < 0.1??? [work in progress]

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 32 / 42

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SLIDE 33

What do we know about the light-fermion Yukawas?

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 33 / 42

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SLIDE 34

Electron Yukawa – Collider bounds

Br(h → e+e−) =

  • κ2

e + ˜

κ2

e

  • Br(h → e+e−)SM

1 +

  • κ2

e + ˜

κ2

e − 1

  • Br(h → e+e−)SM

CMS limit Br(h → e+e−) < 0.0019 [CMS, arxiv:1410.6679] leads to

  • κ2

e + ˜

κ2

e < 611 [Altmannshofer, Brod, Schmaltz, arxiv:1503.04830]

Gain one order of magnitude at a 100 TeV hadron collider with 3000/fb Measure up to a order of a few at a dedicated electron-positron collider

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 34 / 42

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SLIDE 35

(How) Can we probe the light-quark Yukawas?

Processes with off-shell Higgs and external SM particles difficult:

Scalar Higgs current competes with neutral currents induced by g, γ, Z

Two options:

On-shell Higgs decays (e.g. h → φγ) [Kagan et al., arxiv:1406.1722] New probes: DM

h s ¯ s γ

h s ¯ s γ

h χ χ u u d

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 35 / 42

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SLIDE 36

Direct detection – Yukawa dependence

[Bishara, Brod, Uttayarat, Zupan, arXiv:1504.04022]

h χ χ u u d

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 36 / 42

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SLIDE 37

Flavor-changing Higgs couplings

L ⊃ −Ytq¯ tLqR − Yqt¯ qLtR + h.c.

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 37 / 42

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SLIDE 38

Hadronic

[Gorbahn, Haisch, arxiv:1404.4873] h c c g t

c t h g g g

h c u g t u t c c t u h h

Observable Coupling Present bound Future sensitivity t → ch

  • |Ytc|2 + |Yct|2

0.14 2.8 · 10−2 t → uh

  • |Ytu|2 + |Yut|2

0.13 2.8 · 10−2 dn |Im (YtcYct)| 5.0 · 10−4 1.7 · 10−6 |Im (YtuYut)| 4.3 · 10−7 1.5 · 10−9 ∆ACP |Im (Y ∗

utYct)|

4.0 · 10−4 — D − ¯ D mixing

  • |Im (Y ∗

tcY ∗ utYtuYct)|

4.1 · 10−4 1.3 · 10−4

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 38 / 42

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SLIDE 39

Leptonic

[Harnik, Kopp, Zupan, arxiv:1209.1397] τ h τ τ γ µ

Y ∗

ττPL + YττPR

Y ∗

τµPL + YµτPR

+ µ h µ τ γ µ

Y ∗

τµPL + YµτPR

Y ∗

µµPL + YµµPR

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 39 / 42

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SLIDE 40

A hint of new physics?

BR(h → τµ) = (0.84+0.39

−0.37)%

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 40 / 42

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SLIDE 41

Rare τ decays

[Celis, Cirigliano, Passemar, arxiv:1309.3564]

τ → µγ can get large dipole contribution τ → µππ gives more direct constraint

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 41 / 42

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SLIDE 42

Summary

EDMs give strong bounds on Higgs CP violation (and FC transitions)

Complementary to collider constraints . . . but depend on additional assumptions

We don’t know much about the light-fermion Yukawas

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 42 / 42

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SLIDE 43

Appendix

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 1 / 10

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SLIDE 44

CP violation – reminder

In the SM, only CP violation comes from electroweak sector (CKM phase) Switch off weak interactions: K1 =

1 √ 2(K 0 + ¯

K 0), K2 = (K 0 − ¯ K 0)/ √ 2 are CP-even / CP-odd eigenstates Weak interactions lead to a superposition via box diagrams – KL and KS They are not CP eigenstates Analogy would be scalar h0 and pseudoscalar A0 Higgs in 2HDM If Higgs potential is not CP symmetric, lightest mass eigenstate is superposition p h0 + q A0

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 2 / 10

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SLIDE 45

Constraints from EDMs

Contributions to EDMs suppressed by small Yukawas; still get meaningful constraints in future scenario For electron EDM, simply replace charges and couplings Have extra scale mb ≪ Mh ⇒ log m2

b/M2 h

h g g b q

dq(µW ) ≃ −4eQq Nc Q2

b

α (4π)3 √ 2GF mq κq˜ κb m2

b

M2

h

  • log2 m2

b

M2

h

+ π2 3

  • ,

˜ dq(µW ) ≃ −2 αs (4π)3 √ 2GF mq κq˜ κb m2

b

M2

h

  • log2 m2

b

M2

h

+ π2 3

  • ,

w(µW ) ≃ −gs αs (4π)3 √ 2GF κb˜ κb m2

b

M2

h

  • log m2

b

M2

h

+ 3 2

  • .

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 3 / 10

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SLIDE 46

Some models

Model κt κc(u)/κt ˜ κt /κt ˜ κc(u)/κt SM 1 1 NFC Vhu vW /vu 1 MSSM cos α/ sin β 1 GL 1 + O(ǫ2) ≃ 3(7) O(ǫ2) O(κc(u)) GL2 cos α/ sin β ≃ 3(7) O(ǫ2) O(κc(u)) MFV 1 + Re(auv2 W +2bum2 t ) Λ2 1 − 2Re(bu)m2 t Λ2 ℑ(auv2 W +2bum2 t ) Λ2 ℑ(auv2 W ) Λ2 RS 1 − O v2 W m2 KK ¯ Y 2 1 + O v2 W m2 KK ¯ Y 2 1 + O v2 W m2 KK ¯ Y 2 1 + O v2 W m2 KK ¯ Y 2 pNGB 1 + O v2 W f 2

  • + O
  • y2

∗λ2 v2 W M2 ∗

  • 1 + O
  • y2

∗λ2 v2 W M2 ∗

  • O
  • y2

∗λ2 v2 W M2 ∗

  • O
  • y2

∗λ2 v2 W M2 ∗

  • Joachim Brod (JGU Mainz)

Nonstandard Yukawa Couplings 4 / 10

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SLIDE 47

Electron Yukawa

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 5 / 10

slide-48
SLIDE 48

Limits from electron EDM

Constraint on ye · ˜ c from electron EDM ˜ c 10−3 for SM electron Yukawa [McKeen et al., Phys.Rev. D86 (2012) 113004

[arXiv:1208.4597[hep-ph]] – updated with new ACME result]

Vanishes if Higgs does not couple to electron, or if there are cancellations

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 6 / 10

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SLIDE 49

Indirect bounds: Real part – (g − 2)e

Usually, the measurement of ae ≡ (g − 2)e/2 is used to extract α Using independent α measurement, can make a prediction for ae

[cf. Giudice et al., arXiv:1208.6583]

With

α = 1/137.035999037(91) [Bouchendira et al., arXiv:1012.3627] ae = 11596521807.3(2.8) × 10−13 [Gabrielse et al. 2011]

. . . we find |κe| 3000 Bound expected to improve by a factor of 10 in the next few years

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 7 / 10

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SLIDE 50

Indirect bounds: Real part – rare B decays

b s e+ u c t W ¯ Bs Z e− b s e+ u c t W ¯ Bs h e−

SM prediction [Bobeth et al., arXiv:1311.0903]

Br(Bs → e+e−)SM = (8.54 ± 0.55) × 10−14 Br(Bd → e+e−)SM = (2.48 ± 0.21) × 10−15

Current bounds [CDF 2009]

Br(Bs → e+e−) < 2.8 × 10−7 Br(Bd → e+e−) < 8.3 × 10−8

. . . leads to |κe| = O(106)

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 8 / 10

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SLIDE 51

Collider bounds: LEP II

e− e+ γ h b ¯ b e− e+ γ γ, Z b ¯ b

LEP / LEP II did not run on the Higgs resonance They collected ∼ 500/pb per experiment between √s = 189 . . . 207 GeV A bound could be obtained via “radiative return” to the Z pole Requiring Nr.r./

  • Nbkg. = 1 we find
  • κ2

e + ˜

κ2

e 2000

A dataset at √s = 130 GeV leads a similar bound

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 9 / 10

slide-52
SLIDE 52

Collider bounds: Future e+e− machines

−150 −100 −50 50 100 150 √s − Mh [MeV] 50 100 150 200 250 σ(e+e− → h → b¯ b)SM [ab] R = 0.05% R = 0.025% R = 0.01%

A future e+e− machine. . .

collecting 100 fb−1 on the Higgs resonance assuming 0.05% beam-energy spread

. . . would be sensitive to

  • κ2

e + ˜

κ2

e ∼ 15

Joachim Brod (JGU Mainz) Nonstandard Yukawa Couplings 10 / 10