Last Talk Tilman Plehn Questions Couplings Operators BSM Higgs The Last Talk with Nothing New to Say Tilman Plehn Universit¨ at Heidelberg Amherst, May 2014
Last Talk Higgs Questions Tilman Plehn 1. What is the ‘Higgs’ Lagrangian? Questions Couplings – psychologically: looked for Higgs, so found a Higgs Operators – CP-even spin-0 scalar expected, which operators? BSM Higgs spin-1 vector unlikely spin-2 graviton unexpected – ask flavor colleagues [Cabibbo–Maksymowicz–Dell’Aquila–Nelson angles]
Last Talk Higgs Questions Tilman Plehn 1. What is the ‘Higgs’ Lagrangian? Questions Couplings – psychologically: looked for Higgs, so found a Higgs Operators – CP-even spin-0 scalar expected, which operators? BSM Higgs spin-1 vector unlikely spin-2 graviton unexpected – ask flavor colleagues [Cabibbo–Maksymowicz–Dell’Aquila–Nelson angles] 2. What are the coupling values? [SFitter] – ‘coupling’ after fixing operator basis – Standard Model Higgs vs anomalous couplings
Last Talk Higgs Questions Tilman Plehn 1. What is the ‘Higgs’ Lagrangian? Questions Couplings – psychologically: looked for Higgs, so found a Higgs Operators – CP-even spin-0 scalar expected, which operators? BSM Higgs spin-1 vector unlikely spin-2 graviton unexpected – ask flavor colleagues [Cabibbo–Maksymowicz–Dell’Aquila–Nelson angles] 2. What are the coupling values? [SFitter] – ‘coupling’ after fixing operator basis – Standard Model Higgs vs anomalous couplings 3. What does all this tell us? [Review 1403.7191] – strongly interacting models – TeV-scale new physics – weakly interacting extended Higgs sectors – Higgs portal, link to baryogenesis, dark matter,...
t Last Talk Naive Higgs Couplings W,Z Tilman Plehn Standard Model operators [SFitter: D¨ uhrssen, Klute, Lafaye, TP , Rauch, Zerwas] Questions Couplings – assume: narrow CP-even scalar b,t W,Z Operators Standard Model operators couplings proportional to masses? BSM Higgs – couplings from production & decay rates H → ZZ gg → H H → WW qq → qqH H → b ¯ ← → g HXX = g SM ← → HXX ( 1 + ∆ X ) b gg → t ¯ tH H → τ + τ − qq ′ → VH H → γγ
t Last Talk Naive Higgs Couplings W,Z Tilman Plehn Standard Model operators [SFitter: D¨ uhrssen, Klute, Lafaye, TP , Rauch, Zerwas] Questions Couplings – assume: narrow CP-even scalar b,t W,Z Operators Standard Model operators couplings proportional to masses? BSM Higgs – couplings from production & decay rates H → ZZ gg → H H → WW qq → qqH H → b ¯ ← → g HXX = g SM ← → HXX ( 1 + ∆ X ) b gg → t ¯ tH H → τ + τ − qq ′ → VH H → γγ Total width – non-trivial scaling g 2 g 2 g 4 g 2 → 0 p d N = σ BR ∝ √ Γ tot √ Γ tot ∼ − → = 0 � Γ i ( g 2 ) g 2 + Γ unobs g 2 � Γ i ( g 2 ) < Γ tot → Γ H | min gives constraint from – WW → WW unitarity: g WWH � g SM WWH → Γ H | max [HiggsSignals] – SFitter assumption Γ tot = � obs Γ j [plus generation universality]
Last Talk Now and in the future Tilman Plehn Now [Aspen/Moriond 2013; Lopez-Val, TP , Rauch] Questions L=4.6-5.1(7 TeV)+12-21(8 TeV) fb -1 , 68% CL: ATLAS + CMS Couplings – focus SM-like [secondary solutions possible] Moriond 2013 SM (1+ ∆ x ) Operators SM exp. g x = g x 1 – tree couplings consistent in loops data BSM Higgs data (+ ∆ γ ) – six couplings and ratios from data 0.5 g g vs g t not yet good [similar: Ellis etal, Djouadi etal, Strumia etal, Grojean etal] 0 – assumptions help: ∆ H , ∆ V , ∆ f -0.5 ∆ H ∆ V ∆ f ∆ W ∆ Z ∆ t ∆ b ∆ τ ∆ γ ∆ Z/W ∆ τ /b ∆ b/W
Last Talk Now and in the future Tilman Plehn Now [Aspen/Moriond 2013; Lopez-Val, TP , Rauch] Questions – focus SM-like Couplings [secondary solutions possible] Operators – tree couplings consistent in loops BSM Higgs – six couplings and ratios from data g g vs g t not yet good [similar: Ellis etal, Djouadi etal, Strumia etal, Grojean etal] – assumptions help: ∆ H , ∆ V , ∆ f Higgs portal [Michael’s talk] – model–specific fits next step – why not Higgs portal mixing angle vs invisible width 1 95% CL 68% CL data 0.8 SM (m s 1 ) 0.6 inv / Γ tot 0.4 Γ s 1 0.2 0 0.5 0.6 0.7 0.8 0.9 1 cos 2 χ
Last Talk Now and in the future Tilman Plehn Now [Aspen/Moriond 2013; Lopez-Val, TP , Rauch] Questions – focus SM-like Couplings [secondary solutions possible] Operators – tree couplings consistent in loops BSM Higgs – six couplings and ratios from data g g vs g t not yet good [similar: Ellis etal, Djouadi etal, Strumia etal, Grojean etal] – assumptions help: ∆ H , ∆ V , ∆ f Higgs portal [Michael’s talk] – model–specific fits next step – why not Higgs portal mixing angle vs invisible width 1 LHC HL-LHC LC HL-LC SM (m s 1 ) 0.1 inv / Γ tot Γ s 1 0.01 0.001 0 0.9 0.99 0.999 cos 2 χ
Last Talk Now and in the future Tilman Plehn Now [Aspen/Moriond 2013; Lopez-Val, TP , Rauch] Questions – focus SM-like Couplings [secondary solutions possible] Operators – tree couplings consistent in loops BSM Higgs – six couplings and ratios from data g g vs g t not yet good [similar: Ellis etal, Djouadi etal, Strumia etal, Grojean etal] – assumptions help: ∆ H , ∆ V , ∆ f Higgs portal [Michael’s talk] – model–specific fits next step – why not Higgs portal mixing angle vs invisible width 100 SM cross section maximal mixing – translated into heavy Higgs rate LHC 10 HL-LHC σ (gg → d 1 ) [pb] 1 0.1 0.01 0.002 126 200 300 400 500 600 700 800 900 1000 m d 1 [GeV]
Last Talk Now and in the future Tilman Plehn Now [Aspen/Moriond 2013; Lopez-Val, TP , Rauch] Questions Couplings – focus SM-like [secondary solutions possible] Operators – tree couplings consistent in loops BSM Higgs – six couplings and ratios from data g g vs g t not yet good [similar: Ellis etal, Djouadi etal, Strumia etal, Grojean etal] – assumptions help: ∆ H , ∆ V , ∆ f Higgs portal [Michael’s talk] – model–specific fits next step – why not Higgs portal mixing angle vs invisible width – translated into heavy Higgs rate – direct invisible searches numerically irrelevant ⇒ remember your model hypothesis
Last Talk 2HDM as a consistent UV completion Tilman Plehn How to think of coupling measurements [constant couplings, see Spanno’s talk] Questions Couplings – ∆ x � = 0 violating renormalization, unitarity,... Operators – EFT approach: BSM Higgs (1) define consistent 2HDM, decouple heavy states (2) fit 2HDM model parameters, plot range of SM couplings (3) compare to free SM couplings fit
Last Talk 2HDM as a consistent UV completion Tilman Plehn How to think of coupling measurements [constant couplings, see Spanno’s talk] Questions Couplings – ∆ x � = 0 violating renormalization, unitarity,... Operators – EFT approach: BSM Higgs (1) define consistent 2HDM, decouple heavy states (2) fit 2HDM model parameters, plot range of SM couplings (3) compare to free SM couplings fit Yukawa-aligned 2HDM – ∆ V ↔ ( β − α ) ∆ b , t ,τ ↔ { β, γ b ,τ } ∆ γ ↔ m H ± – ∆ g not free parameter, top partner? custodial symmetry built in at tree level ∆ V < 0 – Higgs-gauge quantum corrections enhanced ∆ V < 0 – fermion quantum corrections large for tan β ≪ 1 ∆ W � = ∆ Z > 0 possible
Last Talk 2HDM as a consistent UV completion Tilman Plehn How to think of coupling measurements [constant couplings, see Spanno’s talk] Questions Couplings – ∆ x � = 0 violating renormalization, unitarity,... Operators – EFT approach: BSM Higgs (1) define consistent 2HDM, decouple heavy states (2) fit 2HDM model parameters, plot range of SM couplings (3) compare to free SM couplings fit UV-complete vs SM coupling fits – 2HDM close to perfect at tree level – ∆ W � = ∆ Z > 0 through loops 0.8 measured data direct fit direct fit ( ∆ V <0) – ignote constraints on UV completion 0.6 aligned 2HDM aligned 2HDM (constr.) ⇒ free SM couplings well defined 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 ∆ ∆ ∆ ∆ ∆ V t b τ γ
Last Talk Error analysis Tilman Plehn Sources of uncertainty [Cranmer, Kreiss, Lopez-Val, TP] Questions Couplings – statistical error: Poisson Operators systematic error: Gaussian, if measured theory error: not Gaussian BSM Higgs [no statistical interpretation, just a range] – simple argument LHC rate 10 % off: no problem LHC rate 30 % off: no problem LHC rate 300 % off: Standard Model wrong – theory likelihood flat centrally and zero far away – profile likelihood construction: RFit [CKMFitter] − 2 log L = χ 2 = � d C − 1 � χ T χ d | d i − ¯ d i | < σ (theo) 0 i | d i − ¯ d i | − σ (theo) χ d , i = i | d i − ¯ d i | > σ (theo) σ (exp) i i
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