holography and dewsb at the lhc
play

Holography and DEWSB at the LHC Veronica Sanz Boston University - PowerPoint PPT Presentation

Holography and DEWSB at the LHC Veronica Sanz Boston University with Johannes Hirn and Adam Martin (Yale) hep-ph/0712.3783 + work in progress What we know: Strong interactions are difficult! Rescaled QCD models are ruled out: S


  1. Holography and DEWSB at the LHC Veronica Sanz Boston University with Johannes Hirn and Adam Martin (Yale) hep-ph/0712.3783 + work in progress

  2. What we know: • Strong interactions are difficult! • Rescaled QCD models are ruled out: S parameter: f π v → W L , Z L π a → S > 0 , O (1) ρ , a 1 ρ T , a T → Peskin-Takeuchi’90 • EW scale strong interactions must be very different from QCD -- But then how do we calculate? • Many attempts have been made...

  3. What’s been done: Very few collider studies! • 4D: Walking Technicolor (Lane) Full Collider Topcolor (Hill) Study Low-ScaleTC (LSTC) (Lane) (D)BESS (Casalbuoni et al) Low-N TC (Sannino) Deconstructed Higgsless (Chivukula) Parton ... Level • 5D: Higgsless (Csaki et al) Composite Higgs (Pomarol et al) ... Common feature: TeV scale spin- resonances ( ρ T , W KK ) 1

  4. What’s been done: Very few collider studies! • 4D: Comprehensive Walking Technicolor (Lane) More Full Collider Topcolor (Hill) Collider studies Study Low-ScaleTC (LSTC) (Lane) (D)BESS (Casalbuoni et al) Low-N TC (Sannino) Deconstructed Higgsless (Chivukula) Parton ... Level • 5D: Higgsless (Csaki et al) Composite Higgs (Pomarol et al) ... Common feature: TeV scale spin- resonances ( ρ T , W KK ) 1

  5. Moving beyond Models: Proposal • Most general has parameters L (SM + spin − 1) O (100) way too many for practical pheno! Need an organizing principle • Start by extending holographic techniques; Can we expose new + distinct features? • NOT a new model, RATHER an organizing scheme • Implement this scheme into matrix-element generator No models currently implemented!

  6. Moving beyond Models: Proposal • Most general has parameters L (SM + spin − 1) O (100) way too many for practical pheno! Need an organizing principle a DEWSB equivalent of what mSUGRA is for MSSM • Start by extending holographic techniques; Can we expose new + distinct features? • NOT a new model, RATHER an organizing scheme • Implement this scheme into matrix-element generator No models currently implemented!

  7. Moving beyond Models: Proposal • Most general has parameters L (SM + spin − 1) O (100) way too many for practical pheno! Need an organizing principle a DEWSB equivalent of what mSUGRA is for MSSM • Start by extending holographic techniques; Can we expose new + distinct features? Short answer: Yes • NOT a new model, RATHER an organizing scheme • Implement this scheme into matrix-element generator No models currently implemented!

  8. Higgsless Basics: • AdS/CFT inspired 5D version of strong DEWSB • 5D interval ; containing z ∈ ( ℓ 0 , ℓ 1 ) gauge fields. SU (2) L ⊗ SU (2) R ℓ 2 • Bulk geometry usually: z 2 ( η µ ν dx µ dx ν − dz 2 ) 0 • BC break EWS KK tower of states; γ , W ± , Z 0 zero modes are W ± +Vector, Axial resonances (not quite!): n , Z n � ℓ 1 • Resonance couplings: dz ℓ 0 z φ A ( z ) φ B ( z ) φ C ( z ) g ABC ∝ ℓ 0

  9. Higgsless cont. • small large N T C g 5 • Spectrum: tower of narrow, weakly interacting resonances (large ) N T C large coupling to comes from plugging W L , Z L in polarizations exchange of many resonances delays unitarity violation • BUT , 5D+bifundamental leads to QCD-like spectrum ; Small perturbations don’t help S > 0 , O (1) (Agashe et al ‘07) Limited Models can be made viable Phenomenology at the expense of = 0 g ffV ∼

  10. Our scheme: Modifying Holography • How can we extend the Holographic framework to incorporate new features? • Effective warp factors: L = − 1 � dx ω V ( z ) F V,NM F NM + ω A ( z ) F A,MN F MN V A 2 g 2 5 � z ω V,A ( z ) = ℓ 0 � 4 � � o V,A o V , o A < 0 z exp 4 ℓ 1 (Hirn, Sanz ’06,’07)

  11. Our scheme: Modifying Holography • How can we extend the Holographic framework to incorporate new features? • Effective warp factors: L = − 1 � dx ω V ( z ) F V,NM F NM + ω A ( z ) F A,MN F MN V A 2 g 2 5 � z ω V,A ( z ) = ℓ 0 � 4 � � o V,A o V , o A < 0 z exp 4 ℓ 1 (Hirn, Sanz ’06,’07) Positive definite Acts like condensate Deformed in IR - power of z o V,A Π V,A ∼ unimportant ( Q ℓ 1 ) 4

  12. Why this deformation? ω V,A = ℓ 0 z e o V,A z 4 / ℓ 4 1 • Allows us to vary the length of the dimension the vector feels relative to the axial M M Dialing for fixed : o A o V m A 2 m A 2 m V 2 m V 2 Remember: m A 1 m A 1 Eigenstates are a W ± m V 1 1 , 2 , Z 0 m V 1 1 , 2 mixture of V, A | ψ X ( z ) � = | V X ( z ) , A X ( z ) � o V = 0 , o A = 0 • Added only 2 new parameters, no new fields • Couplings , etc. will also vary with ℓ 1 , o V , o A g W 1 W Z

  13. Why this deformation? ω V,A = ℓ 0 z e o V,A z 4 / ℓ 4 1 • Allows us to vary the length of the dimension the vector feels relative to the axial M M Dialing for fixed : m V 2 o A o V m A 2 m A 2 m V 2 m V 1 Remember: m A 1 m A 1 Eigenstates are a W ± 1 , 2 , Z 0 m V 1 1 , 2 mixture of V, A | ψ X ( z ) � = | V X ( z ) , A X ( z ) � o V = 0 , o A = 0 • Added only 2 new parameters, no new fields • Couplings , etc. will also vary with ℓ 1 , o V , o A g W 1 W Z

  14. Why this deformation? ω V,A = ℓ 0 z e o V,A z 4 / ℓ 4 1 • Allows us to vary the length of the dimension the vector feels relative to the axial M M Dialing for fixed : m V 2 o A o V m A 2 m A 2 Degenerate spectrum m V 2 m V 1 Remember: m A 1 m A 1 Eigenstates are a W ± 1 , 2 , Z 0 m V 1 1 , 2 mixture of V, A | ψ X ( z ) � = | V X ( z ) , A X ( z ) � o V < 0 , o A = 0 o V = 0 , o A = 0 • Added only 2 new parameters, no new fields • Couplings , etc. will also vary with ℓ 1 , o V , o A g W 1 W Z

  15. Why this deformation? ω V,A = ℓ 0 z e o V,A z 4 / ℓ 4 1 • Allows us to vary the length of the dimension the vector feels relative to the axial m V 2 M M Dialing for fixed : o A o V m A 2 m A 2 Degenerate spectrum m V 2 m V 1 Remember: m A 1 m A 1 Eigenstates are a W ± 1 , 2 , Z 0 m V 1 1 , 2 mixture of V, A | ψ X ( z ) � = | V X ( z ) , A X ( z ) � o V < 0 , o A = 0 o V = 0 , o A = 0 • Added only 2 new parameters, no new fields • Couplings , etc. will also vary with ℓ 1 , o V , o A g W 1 W Z

  16. Why this deformation? ω V,A = ℓ 0 z e o V,A z 4 / ℓ 4 1 • Allows us to vary the length of the dimension the vector feels relative to the axial m V 2 M M Dialing for fixed : o A o V m A 2 m A 2 m V 2 m V 1 Remember: m A 1 m A 1 Eigenstates are a W ± 1 , 2 , Z 0 m V 1 1 , 2 mixture of V, A | ψ X ( z ) � = | V X ( z ) , A X ( z ) � o V = 0 , o A = 0 • Added only 2 new parameters, no new fields • Couplings , etc. will also vary with ℓ 1 , o V , o A g W 1 W Z

  17. Why this deformation? ω V,A = ℓ 0 z e o V,A z 4 / ℓ 4 1 • Allows us to vary the length of the dimension the vector feels relative to the axial m V 2 M M Dialing for fixed : o A o V m A 2 m A 2 m V 2 or Inverted spectrum m V 1 Remember: m A 1 m A 1 Eigenstates are a W ± 1 , 2 , Z 0 m V 1 1 , 2 mixture of V, A | ψ X ( z ) � = | V X ( z ) , A X ( z ) � o V ≪ 0 , o A = 0 o V = 0 , o A = 0 • Added only 2 new parameters, no new fields • Couplings , etc. will also vary with ℓ 1 , o V , o A g W 1 W Z

  18. What do we gain? • Parameter space contains non-QCD like spectrum • WSRs and simple resonance models S ameloriated when de Rafael-Knecht ‘97 M W 1 ∼ = M W 2 Appelquist-Sannino ‘98 • Whenever ; unconventional triboson, 4- ω V � = ω A boson couplings 1 ν ] ( W + [ µ Z 0 ν ] ( Z 0 1 ν ] ) + g 3 ∂ [ ν Z 0 [1 ν W + 1 W Z = g 1 ∂ [ µ W − ν ] ) + g 2 ∂ [ µ W − ν ] ( W − ν ] ) g W − [ µ W − � ℓ 1 � ℓ 1 dz ω V ( V 1 A W + A Z ) · · · � = g 3 ⊃ dz ω A ( V 1 A W + A Z ) · · · g 1 ⊃ � = g 2 ℓ 0 ℓ 0 Same region degenerate (non-QCD) mixed photon coupling g W − 1 W + γ

  19. What do we gain? New pheno. and a new twist on old pheno. • Parameter space contains non-QCD like spectrum • WSRs and simple resonance models S ameloriated when de Rafael-Knecht ‘97 M W 1 ∼ = M W 2 Appelquist-Sannino ‘98 • Whenever ; unconventional triboson, 4- ω V � = ω A boson couplings 1 ν ] ( W + [ µ Z 0 ν ] ( Z 0 1 ν ] ) + g 3 ∂ [ ν Z 0 [1 ν W + 1 W Z = g 1 ∂ [ µ W − ν ] ) + g 2 ∂ [ µ W − ν ] ( W − ν ] ) g W − [ µ W − � ℓ 1 � ℓ 1 dz ω V ( V 1 A W + A Z ) · · · � = g 3 ⊃ dz ω A ( V 1 A W + A Z ) · · · g 1 ⊃ � = g 2 ℓ 0 ℓ 0 Same region degenerate (non-QCD) mixed photon coupling g W − 1 W + γ

  20. Exploring and : o V o A Along o A = 0 , o V < 0 Level repulsion Only vector Both resonances unitarizes Nonzero in W L W L → W L W L g W 1 , 2 W γ

  21. What about SM fermions? • Coupling of fermions to the new resonances will determine the best production methods at the LHC • Full 5D treatment of fermions would re-introduce many parameters... For starters: one more parameter g ffV g ffW = g SM • We can study several models of fermion interactions = g ffV κ g ffW ideally delocalized ∼ = 0 g ffV mostly composite t R ≫ g t R t R V g ffV

Download Presentation
Download Policy: The content available on the website is offered to you 'AS IS' for your personal information and use only. It cannot be commercialized, licensed, or distributed on other websites without prior consent from the author. To download a presentation, simply click this link. If you encounter any difficulties during the download process, it's possible that the publisher has removed the file from their server.

Recommend


More recommend