Anomaly-mediated supersymmetry breaking “demystified” based on JHEP03(2009)123 (arXiv:0902.0464) Jae Yong Lee (KIAS) in collaboration with Dong-Won Jung (NCU) PHENO 2009 SYMPOSIUM 1
OUTLINE Introduction Conformal symmetry, gravity and anomaly Superconformal symmetry and anomaly Chiral anomaly supermultiplet (CASM) and chiral compensator Anomaly-mediated SUSY breaking in MSSM Conclusion 2
Introduction SUSY Hidden Sector Visible Sector SUSY breaking by (superconformal) anomaly-mediation Randall, Sundrum ( ’ 98); Giudice, Luty, Murayama, Rattazzi ( ’ 98) Chiral compensator χ in Einstein supergravity � χ 3 � = 1 + θθ m 3 / 2 m 3 / 2 : gravitino mass gaugino mass, sfermion mass, A-term ∝ m 3 / 2 3
Conformal symmetry, gravity, and anomaly renormalization scale transforms as conformal (or scale) transformations x m e ̺ x m µ → e − ̺ µ. → p m e − ̺ p m → µ 4
The ρ is • a real parameter for shifting the scale. • the Nambu-Goldstone Boson (NGB), if conformal symmetry is “ spontaneously ” broken. • contained in Einstein gravity where the matter Lagrangian couples to the integral measure √ g with ρ =ln √ g. • brought in at loops along with the renormalization scale μ in quantum theory. ⊃ ln µ 2 → ln µ 2 − 2 ̺ 5
The ρ is the dilaton. • a real parameter for shifting the scale. • the Nambu-Goldstone Boson (NGB), if conformal symmetry is “ spontaneously ” broken. • contained in Einstein gravity where the matter Lagrangian couples to the integral measure √ g with ρ =ln √ g. • brought in at loops along with the renormalization scale μ in quantum theory. ⊃ ln µ 2 → ln µ 2 − 2 ̺ 6
coupling of dilaton to conformal anomaly Example: massless QCD theory � d 4 x ̺ T m = S e ff m , Coupling β QCD ( g ) T m F a nl F anl = Trace (or conformal) anomaly m 2 g Fugikawa ’ s path-integral method Feynman diagrams with background field method See Peskin ’ s QFT book 7
coupling of dilaton to conformal anomaly Example: massless QCD theory � d 4 x ̺ T m = S e ff m , Coupling β QCD ( g ) T m F a nl F anl = Trace (or conformal) anomaly m 2 g Fugikawa ’ s path-integral method Z g Z 1 / 2 = 1 Feynman diagrams with background field method A See Peskin ’ s QFT book 8
coupling of dilaton to conformal anomaly Example: massless QCD theory � d 4 x ̺ T m = S e ff m , Coupling β QCD ( g ) T m F a nl F anl = Trace (or conformal) anomaly m 2 g Fugikawa ’ s path-integral method Z g Z 1 / 2 = 1 Feynman diagrams with background field method A See Peskin ’ s QFT book ln µ 2 → ln µ 2 − 2 ̺ 9
Superconformal symmetry and anomaly Supersymmetry Conformal symmetry 10
Conformal supergravity ψ m ( x ) + 1 a ( x ) + i θθψ m ( x ) − i H m ( x, θ , ¯ θ ) = θσ a ¯ θ ¯ ¯ 2 θθ ¯ θ ¯ 4 θθ ¯ θ ¯ θ ˆ ν m ( x ) θ e m 2 U(1)_R gauge gravitino vierbein ψ m e m ν m ˆ α a 3=4-1 8=16-4-4 5=16-6-4-1 (Matter) Supercurrent Energy-momentum R-current SUSY current tensor j R S m T m m α n ∂ m j R γ m S m T m α = 0 m = 0 m = 0 11
Conformal supergravity ψ m ( x ) + 1 a ( x ) + i θθψ m ( x ) − i H m ( x, θ , ¯ θ ) = θσ a ¯ θ ¯ ¯ 2 θθ ¯ θ ¯ 4 θθ ¯ θ ¯ θ ˆ ν m ( x ) θ e m 2 U(1)_R gauge gravitino vierbein ψ m e m ν m ˆ α a 3=4-1 8=16-4-4 5=16-6-4-1 (Matter) Supercurrent Energy-momentum R-current SUSY current tensor j R S m T m m α n ∂ m j R γ m S m T m α = 0 m = 0 m = 0 12
Gravity and Matter Anomaly GRAVITY MATTER dilaton conformal anomaly SUSY anomaly dilatino more? more? chiral chiral vector current 13
Chiral anomaly supermultiplet and chiral compensator Suppose that all the three symmetries are “ anomalous ” . r ≡ ∂ m j R ˚ a, b ξ α ≡ γ m S m t ≡ T m ˚ m α m 2 1 4 1 √ ¯ X ( x, θ ) A ( x ) + 2 θξ ( x ) + θθ F ( x ) , Chiral anomaly supermultiplet (CASM) D X = 0 ≡ = a + ib A ˚ = t + i ˚ F r 14
Chiral anomaly supermultiplet and chiral compensator Suppose that all the three symmetries are “ anomalous ” . r ≡ ∂ m j R ˚ a, b ξ α ≡ γ m S m t ≡ T m ˚ m α m 2 1 4 1 √ ¯ X ( x, θ ) A ( x ) + 2 θξ ( x ) + θθ F ( x ) , Chiral anomaly supermultiplet (CASM) D X = 0 ≡ = a + ib A ˚ = t + i ˚ F r U(1)_R gauge gravitino vierbein ψ m e m M ∗ ν m ˆ α a 2 3=4-1 8=16-4-4 5=16-6-4-1 √ r o 2 θ ¯ t χ 3 ( x, θ ) ≡ e 2 ̺ ( x )+2 i δ ( x ) [1 + a s Ψ ( x ) + θθ M ∗ ( x )] n e p m o c l a r i h C Ψ α ∼ σ α ˙ m ¯ α (Nambu-Goldstino = dilatino) ¯ α ψ m ˙ 15
Chiral anomaly supermultiplet and chiral compensator Suppose that all the three symmetries are “ anomalous ” . r ≡ ∂ m j R ˚ a, b ξ α ≡ γ m S m t ≡ T m ˚ m α m 2 1 4 1 √ ¯ X ( x, θ ) A ( x ) + 2 θξ ( x ) + θθ F ( x ) , Chiral anomaly supermultiplet (CASM) D X = 0 ≡ = a + ib A ˚ = t + i ˚ F r U(1)_R gauge gravitino vierbein ψ m e m M ∗ ν m ˆ α a 2 3=4-1 8=16-4-4 5=16-6-4-1 √ r o 2 θ ¯ t χ 3 ( x, θ ) ≡ e 2 ̺ ( x )+2 i δ ( x ) [1 + a s Ψ ( x ) + θθ M ∗ ( x )] n e p m o c l a r i h C Ψ α ∼ σ α ˙ m ¯ α (Nambu-Goldstino = dilatino) ¯ α ψ m ˙ 16
Coupling of the CASM to the chiral compensator � d 4 x d 2 θ χ 3 ( x, θ ) X ( x, θ ) + h.c. S X = � d 4 x [ e 2 ̺ +2 i δ ( M ∗ A + ¯ in components, S X = Ψ ξ + F ) + h.c. ] soft susy breaking terms conformal anomaly � M ∗ � = m 3 / 2 , A = the lowest comp. of CASM α W a α ⇒ A| = λ a λ a X = W a for example, gaugino mass term M ∗ A ⇒ m 3 / 2 λ a λ a 17
Anomaly-mediated SUSY breaking in MSSM � + e 2 gV φ i d 4 x d 2 θ d 2 ¯ = S θ φ i � � � (Simplified MSSM action) � 1 � α + 1 3! y ijk φ i φ j φ k d 4 x d 2 θ 4 W a α W a + + h.c. interaction CASM soft term X β ( g ) M λ = β ( g ) 1 2 g W a α W a m 3 / 2 4 W a α W a α g α A ijk = − 1 1 3! y ijk φ i φ j φ k 3! ( γ i + γ j + γ k ) y ijk φ i φ j φ k − ( γ i + γ j + γ k ) y ijk m 3 / 2 18
Anomaly-mediated SUSY breaking in MSSM � + e 2 gV φ i d 4 x d 2 θ d 2 ¯ = S θ φ i � � � (Simplified MSSM action) � 1 � α + 1 3! y ijk φ i φ j φ k d 4 x d 2 θ 4 W a α W a + + h.c. β - function CASM interaction soft term X β ( g ) M λ = β ( g ) 1 2 g W a α W a m 3 / 2 4 W a α W a γ - function α g α A ijk = − 1 1 3! y ijk φ i φ j φ k 3! ( γ i + γ j + γ k ) y ijk φ i φ j φ k − ( γ i + γ j + γ k ) y ijk m 3 / 2 β ( g ) = − g 3 � 16 π 2 [3 C A (adj . ) − T A ( φ i )] i 1 γ j ikl y jkl − 4 g 2 δ j i = − 32 π 2 [ y ∗ i C A ( φ i )] 19
ln µ 2 → ln µ 2 − 2 ̺ Supergraphs : (a) vector, (b) ghost, (c) chiral one-loop contribution to the vector superpropagator. 20
ln µ 2 → ln µ 2 − 2 ̺ β - function Supergraphs : (a) vector, (b) ghost, (c) chiral one-loop contribution to the vector superpropagator. Z g Z 1 / 2 = 1 V β ( g ) = − g 3 � 16 π 2 [3 C A (adj . ) − T A ( φ i )] i M λ = β ( g ) m 3 / 2 g 21
ln µ 2 → ln µ 2 − 2 ̺ Supergraphs : one-loop contribution to the Yukawa term. 22
ln µ 2 → ln µ 2 − 2 ̺ ϒ - function Supergraphs : one-loop contribution to the Yukawa term. 1 γ j ikl y jkl − 4 g 2 δ j i = − 32 π 2 [ y ∗ i C A ( φ i )] A ijk = − ( γ i + γ j + γ k ) y ijk m 3 / 2 23
Supergraphs : these one-loops do NOT contribute to the Yukawa term. Due to the non-renormalization theorems 24
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