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Electroweak Symmetry Breaking with Holomorphic Supersymmetric NambuJona-Lasinio Model Talk at PHENO 2010 OTTO C. W. KONG Natl Central U, Taiwan 1 NambuJona-Lasinio Model :- Otto Kong (NCU) 09ntnu-1 dynamical symmetry


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SLIDE 1

Electroweak Symmetry Breaking with Holomorphic Supersymmetric Nambu–Jona-Lasinio Model

— Talk at PHENO 2010 OTTO C. W. KONG

— Nat’l Central U, Taiwan

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SLIDE 2

Otto Kong (NCU) — 09ntnu-1

1

Nambu–Jona-Lasinio Model :-

  • dynamical symmetry breaking
  • four-fermion interaction

Lψ = i ¯ ψ+σµ∂µψ+ + i ¯ ψ−σµ∂µψ− + g2 ¯ ψ+ ¯ ψ−ψ+ψ− − → Lψ − (µφ† + gψ+ψ−)(µφ + g ¯ ψ+ ¯ ψ−) = i ¯ ψ+σµ∂µψ++i ¯ ψ−σµ∂µψ−−µ2φ†φ−µg(φ† ¯ ψ+ ¯ ψ−+φψ+ψ−)

  • auxiliary scalar field φ

(no kinetic term)

  • EL-eq for φ† gives φ as composite

φ = −g/µ ¯ ψ+ ¯ ψ−

  • φ = 0 =

⇒ symmetry breaking and fermion mass

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SLIDE 3

Otto Kong (NCU) — 09ntnu-2a

2

→ low energy effective field theory :-

  • 1-loop effective potential for φ gives gap equation

φ = 0 solution for g2Λ2

8π2 > 1

  • Dirac fermion mass m = µg φ for ψ+ – ψ−

g2 ¯ ψ+ ¯ ψ−ψ+ψ− = ⇒ g2 ¯ ψ+ ¯ ψ−

  • ψ+ψ−
  • kinetic term for φ through wave-function renormalization

fermion-loop propagator with Yukawa vertices (m ≪ Λ) Z = N

cµ2g2

16π2

  • ln Λ2

M2 + O(1)

  • Higgs with mass 2m and a Goldstone boson
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SLIDE 4

Otto Kong (NCU) — 09ntnu-2b

3

φ − → φ/ √ Z :-

  • Lψ = i ¯

ψ+σµ∂µψ+ + i ¯ ψ−σµ∂µψ− + ∂µφ†∂µφ −˜ µ2φ∗φ −

˜ λ 2 (φ†φ)2 − ˜

yφψ+ψ− + h.c. — ˜ y =

µg √ Z = 4π √N

c

1

ln (Λ2/M2)

— ˜ µ2 =

  • 8π2

N

cg2 − (Λ2 − M 2)

  • 2

ln (Λ2/M2)

— ˜ λ =

32π2 N

cln (Λ2/M2)

  • condition for φ = 0 gives gap equation result
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SLIDE 5

Supersymmetrizing the NJL Model (Naively):-

  • i ¯

ψ+σµ∂µψ+ − →

  • d4θ ¯

Φ+Φ+

  • g2 ¯

ψ+ ¯ ψ−ψ+ψ− − →

  • d4θ g2 ¯

Φ+ ¯ Φ−Φ+Φ−

  • −µg φψ+ψ−

− →

  • d2θ µg ΦΦ+Φ−
  • −µ2φ∗φ

− →

  • d2θ

µ 2 ΦΦ

BUT :-

  • φ = −g/µ ¯

ψ+ ¯ ψ− implies µ2φ∗φ = −µg φψ+ψ− = g2 ¯ ψ+ ¯ ψ−ψ+ψ− (no SUSY !)

  • no nontrivial vacuum without SUSY breaking
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SLIDE 6

The Supersymmetric NJL Model :-

  • i ¯

ψ+σµ∂µψ+ − →

  • d4θ ¯

Φ+Φ+ (1 − m2θ2¯ θ2)

  • g2 ¯

ψ+ ¯ ψ−ψ+ψ− − →

  • d4θ g2 ¯

Φ+ ¯ Φ−Φ+Φ−

  • −µg φψ+ψ−

− →

  • d2θ µg Φ2Φ+Φ−
  • −µ2φ∗φ

− →

  • d2θ µ Φ1Φ2 +
  • d4θ ¯

Φ1Φ1 BUT :-

  • EL-eq for Φ2 gives Φ1 = −g Φ+Φ−

implies

  • d4θ ¯

Φ1Φ1 =

  • d4θ g2 ¯

Φ+ ¯ Φ−Φ+Φ−

  • Φ2 not the composite Φ1 plays the Higgs superfield

Φ1 = 0

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SLIDE 7

An Alternative Supersymmetrization ?

  • i ¯

ψ+σµ∂µψ+ − →

  • d4θ ¯

Φ+Φ+ (1 − m2θ2¯ θ2)

  • −µg φψ+ψ−

− →

  • d2θ µg Φ0Φ+Φ−
  • −µ2φ∗φ

− →

  • d2θ

µ 2 Φ0Φ0

= ⇒ L =

  • d4θ

Φ+Φ+ + ¯ Φ−Φ−)(1 − m2θ2¯ θ2)

  • +
  • d2θ

µ

2 Φ2 0 + √µGΦ0Φ+Φ−

  • + h.c.
  • consider superpotential

W = G

2 Φ+Φ−Φ+Φ−

− → W − 1

2(√µΦ0 +

√ GΦ+Φ−)(√µΦ0 + √ GΦ+Φ−)

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SLIDE 8

Otto Kong (NCU) — 09ntnu-6

7

With Holomorphic Four-Chiral Superfield Interaction :-

  • W = G

2 Φ+Φ−Φ+Φ− contains no g2 ¯

ψ+ ¯ ψ−ψ+ψ−

  • EL-eq for auxiliary superfield Φ0 gives Φ0 = −
  • G/µ Φ+Φ−

implies

µ 2 Φ2 0 = −

µG 2

Φ0Φ+Φ− = G

2 Φ+Φ−Φ+Φ−

  • Φ0

= ⇒

G 2 Φ+Φ− Φ+Φ−

Dirac mass for Φ+–Φ−

  • kinetic term for Φ0 from wave-function renormalization

through Φ+–Φ− loop with Yukawa vertices

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SLIDE 9

Otto Kong (NCU) — 09ntnu-7

8

→ low energy effective field theory :-

  • (gauged-)kinetic term
  • d4θ Z0 ¯

Φ0 e2VΦ Φ0

  • 1 + (2m2 + A2)θ2¯

θ2 where Z0 = N

cµG

16π2

  • ln Λ2

M2 + O(1)

˜ m2

0 = −(2m2 + A2), tachyonic soft mass (cf. radiative EWSB)

— ˜ y = √

µG √Z0 = 4π √N

c

1

ln (Λ2/M2)

— ˜ µ =

µ Z0 = 16π2 N

cG

1 ln (Λ2/M2)

  • µ

2 Φ2 term =

⇒ Φ in real representation of symmetry

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SLIDE 10

Otto Kong (NCU) — 09ntnu-8

9

Condensate/Mass Generation — A Comparison :-

  • NJL : g2 ¯

ψ+ ¯ ψ−

  • ψ+ψ−

− → −µg φ ψ+ψ− — symmetry breaking with bi-fermion condensate φ

  • SNJL :
  • d4θ g2¯

Φ+ ¯ Φ−

  • Φ+Φ−

− → −g

  • F †

1

  • [A+F− + A−F+ − ψ+ψ−]
  • F †

1 = −µA2

  • — F1 = −g A+F− + A−F+ − ψ+ψ−, sbi-fermion condensate
  • HSNJL :
  • d2θ −GΦ+Φ− Φ+Φ−

− → √µG A0 [A+F− + A−F+ − ψ+ψ−] + √µG F0 A+A− — A0 = −

  • G/µ A+A−, a bi-scalar condensate
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SLIDE 11

Otto Kong (NCU) — 09ntnu-9

10

T owards

EW Symmetry Breaking

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SLIDE 12

Otto Kong (NCU) — 09ntnu-10

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NJL Model → SM :-

  • four-fermion interaction

g2 ¯ Q¯ tcQtc

  • Higgs doublet as top-composite

φ = −g/µ( ¯ Q¯ tc)

  • top condensate breaks EW symmetry → fermion masses

— gives top quark mass at to infared quasi-fixed point

  • high mt ∼ 218 GeV

(Λ ∼ 1019 GeV )

Bardeen, Hill, Lindner 90

mt ∼ 214 − 202 GeV (Λ ∼ 1015 − 1019 GeV )

Marciano 89,90

mt ∼ 253 GeV

Miransky, Tanabashi, Yamawaki 89; King & Mannan 90,91

  • extensions, e.g. two-Higgs-doublet model
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SLIDE 13

Otto Kong (NCU) — 09ntnu-11

12

SNJL Models → MSSM (why SUSY ?):-

  • SM → MSSM — hierarchy/fine-tuning problem

scalar field is somewhat sick

  • SM fermion spectrum sort of fixed (anomaly cancelation)

e.g. OK 96

scalar content — only part arbitrary (cf. gauge symmetry)

  • SUSY — technically natural hierarchy

scalar as (part of) chiral superfield (constrained as fermions) Vs Georgi’s survival hypothesis

  • BUT µ-problem — vectorlike pair of Higgs superfields
  • SNJL models solve our problems

— and avoid fine-tuning of four-quark coupling(s)

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SLIDE 14

Otto Kong (NCU) — 09ntnu-12

13

Towards the MSSM :-

  • consider W = G ε

αβ ˆ

Qα ˆ U c ˆ Q′β ˆ Dc (1 + Bθ2) W − → W − µ ( ˆ Hd − λu ˆ Q ˆ U c)( ˆ Hu − λd ˆ Q′ ˆ Dc)(1 + Bθ2) = (−µ ˆ Hd ˆ Hu + yu ˆ Q ˆ Hu ˆ U c + yd ˆ Hd ˆ Q′ ˆ Dc)(1 + Bθ2)

  • two composites

— ˆ Hu = yd

µ ˆ

Q′ ˆ Dc and ˆ Hd = yu

µ

ˆ Q ˆ U c

  • low energy effective theory looks like MSSM (A = B)
  • symmetric role for ˆ

Hu and ˆ Hd

  • also : µλuλd = yuyd

µ

= G

  • — numerical lifted through non-universal soft masses

— expect hu > ∼ hd (Vs UBB in D-flat)

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SLIDE 15

Otto Kong (NCU) — 09ntnu-13

14

Holomorphic Vs Old Model (for MSSM) :-

  • bottom together with (vs only) top mass at quasi-fixed point

⋆ both (vs one) Higgs superfields as composites

  • large (vs small) tanβ
  • At ≃ Ab ≃ B

(vs At ≃ 0)

  • m2

H d ≃ −(m2 Q + m2 b + |Ab|2)

plus (vs only) m2

H u ≃ −(m2 Q + m2 t + |At|2)

⋆ full W [= Gijkh QiU c

j QkDc h(1 + Aθ2) + Ge ij Q

3U c 3 LiEc

j(1 + Aθ2)]

— non-holomorphic case needs similar holomorphic terms for Yukawa couplings of down-type quarks and charged leptons

  • sbottom and stop condensates for ui and di + ℓi masses

(vs top condensate and stop condensates for ui and di + ℓi masses)

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SLIDE 16

Otto Kong (NCU) — 09ntnu-14

15

Numerical (RG analysis) Results :-

  • earlier MSSM t − b − τ quasi-fixed point analysis

(without background model)

Froggatt et.al 93

mt = 184.3 ± 6.8 GeV, mh = 121.8 ± 4.3 GeV

  • ? mt = 171.2 ± 2.1 GeV
  • old SNJL: MSSM t quasi-fixed point analysis

Carena et.al 92

— high Λ and large tanβ lower mt

  • infared quasi-fixed point NOT necessary

SNJL – yt blows up at Λ HSNJL – yt and yb blows up at ∼ Λ

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SLIDE 17

Otto Kong (NCU) — 09ntnu-14p

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Our Solution :-

35 40 45 50 55 60 65 70 75 104 106 108 1010 1012 1014 1016 tanβ Λ [GeV] Ms = 10 TeV Ms = 1 TeV Ms = 200 GeV

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SLIDE 18

Otto Kong (NCU) — 09ntnu-14r

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Illustrative yt and yb :-

0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 103 104 105 106 107 108 109 1010 1011 yt, yb µ [GeV] Ms = 1 TeV tanβ = 57.8 Λb = 104 GeV tanβ = 42.8 Λb = 1010 GeV yb yt

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SLIDE 19

Otto Kong (NCU) — 09ntnu-14h

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Mass of the lightest Higgs boson :-

90 95 100 105 110 115 120 125 130 103 104 mh [GeV] Ms [GeV] 200

mA ≥ 100 GeV mA = 140 GeV mA = 130 GeV mA = 120 GeV mA = 110 GeV mA = 100 GeV

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SLIDE 20

Otto Kong (NCU) — 09ntnu-15

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Final Remarks :-

  • SNJL model with holomorphic term works
  • may provide more interesting version of MSSM

— SUSY : scalar → chiral superfield — problematic MSSM superfield spectrum — vectorlike Higgs superfields, turn up as composites — four-superfield (G) term from integrated out heavy Higgs superfields ? — more natural B (and A) term, and all Yukawa coupling

  • chiral symmetry explicitly broken
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SLIDE 21

Otto Kong (NCU) — end

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T HANK Y OU !

well done Otto !