SM HIGGS PRODUCT ION AND DECAY AT T HE LHC

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1 SM IGGS PRODUCT ION AND DECAY AT T E LC Michael Spira (PSI) I Introduction II is Boson Decays III is Boson Production IV Conclusions

2 I INT RODUCT ION we have found the is: M 125 GeV dominant weihts / 2 GeV Σ ATLAS Data S/B Weihted Si+Bk Fit (m =126.5 GeV) Bk (4th order polynomial) s=7 TeV, Ldt=4.8fb -1 s=8 TeV, Ldt=5.9fb γγ Σ weihts - Bk m γγ [GeV] Events/5 GeV Data (*) Backround ZZ Backround Z+jets, tt Sinal (m =125 GeV) Syst.Unc. ATLAS (*) ZZ 4l 15-1 s = 7 TeV: Ldt = 4.8 fb -1 s = 8 TeV: Ldt = 5.8 fb m 4l [GeV]

3 . is Boson Production t, b À M [GeV] LC is XS WG t t Õ Õ Ï Ï Õ Õ Ï Ï À σ(pp +X) [pb] LC IGGS XS WG s= 8 TeV pp (NNLO+NNLL QCD + NLO EW) pp qq (NNLO QCD + NLO EW) pp pp W (NNLO QCD + NLO EW) pp Z (NNLO QCD +NLO EW) pp tt (NLO QCD) bb (NNLO QCD in 5FS, NLO QCD in 4FS) M [GeV] is BR + Total Uncert [%] LC IGGS XS WG 2013 ττ bb WW ZZ cc γ γ Z γ µµ

4 Discovery: LC is mass couplins spin CP λ? [simplified κ framework]

5 II IGGS BOSON DECAYS Partial Width QCD Electroweak Total on-shell is b b/c c 0.2% 0.5% 0.5% NNNNLO / NLO τ + τ /µ + µ 0.5% 0.5% NLO 3% 1% 3% NNNLO approx. / NLO γγ < 1% < 1% 1% NLO / NLO Zγ < 1% 5% 5% (N)LO / LO WW/ZZ 4f < 0.5% 0.5% 0.5% (N)NLO QCD: variation µ R = [1/2,2]µ 0 elw: missin O estimated from known structure at NLO different uncertainties added linearly for each channel parametric uncertainties: m t = 172.5±1 GeV α s (M Z ) = 0.118± m b (m b ) = 4.18±0.03 GeV m c (3GeV) = 0.986±0.025 GeV different uncertainties added quadratically for each channel total uncertainties: parametric & theor. uncertainties added linearly

6 YR3 DECAY & Prophecy4f YR4 % % is BR + Total Uncert [%] ττ cc bb γγ Zγ WW ZZ LC IGGS XS WG µµ M [GeV] Denner, einemeyer, Puljak, Rebuzzi, S. refinements input parameters full NLO elw. corrections to f f NLO quark-mass effects in

7 III IGGS BOSON PRODU CT ION (i) t, b Geori, Glashow, Machacek, Nanopoulos NLO QCD corrections:...0% S., Djouadi, Graudenz, Zerwas Dawson, Kauffman NNLO calculated for m t M φ further increase by 20 30% [mass effects small] Marzani, Ball, Del Duca, Forte, Vicini arlander, Ozeren Pak, Roal, Steinhauser arlander, Kilore Anastasiou, Melnikov Ravindran, Smith, van Neerven N 3 LO for m t M φ scale stabilization scale dependence: < 5% Moch, Vot Ravindran de Florian, Mazzitelli, Moch, Vot Anastasiou, Duhr, Dulat, Furlan, Gehrmann, erzo, Mistlberer Ball, Bonvini, Forte, Marzani, Ridolfi

8 Anastasiou, Duhr, Dulat, erzo, Mistlberer

9 N 3 LL soft luon resummation: < 2% elw. corrections: 5% Catani, de Florian, Grazzini, Nason Ravindran Ahrens, Becher, Neubert, Yan Ball, Bonvini, Forte, Marzani, Ridolfi Bonvini, Marzani Schmidt, S. Alietti,... Derassi, Maltoni Actis, Passarino, Sturm, Uccirati impl. of in POWEG includin mass NLO Banaschi, Derassi, Slavich, Vicini

10 (ii) W/Z fusion: pp W W /Z Z Õ Ï À Cahn, Dawson ikasa Atarelli, Mele, Pitolli Ï Õ QCD corrections DIS: % [approx] 2 loop: < 1% [approx] 3 loop: < 0.3% elw. corrections: % an, Valencia, Willenbrock Fiy, Oleari, Zeppenfeld Berer, Campbell Bolzano, Maltoni, Moch, Zaro Cacciari, Dreyer, Karlber, Salam, Zanderihi Dreyer, Karlber Ciccolini, Denner, Dittmaier AWK, VBFNLO, VBF@NNLO, PROVBF MG5 amc@nlo, POWEG

11 (iii) is strahlun: pp W /Z W/Z + Õ Ï Ï Glashow,... Kunszt,... Õ À QCD corrections DY: 30% 2 loop: < 5% electroweak corrections: % an, Willenbrock Brein, Djouadi, arlander Ciccolini, Dittmaier, Krämer AWK, VNNLO, MCFM, VNNLO, NNLOPS, MG5 amc@nlo, POWEG W/Z + : fully NNLO QCD Ferrera, Grazzini, Tramantano Z: 20% [QCD corrections in TL: lare] Altenkamp, Dittmaier, arlander, Rzehak, Zirke asselhuhn, Luthe, Steinhauser

12 Ø Ø (iv) Bremsstrahlun: pp t t+ Õ Ø Ø Kunszt Gunion Marciano, Paie Õ dominant t th t tb b LC top Yukawa cpl. [direct] QCD corrections [SM]: 20% Beenakker, Dittmaier, Krämer, Plümper, S., Zerwas [threshold suppressed: σ LO β 4 Dawson, Orr, Reina, Wackeroth ] Broio, Ferrolia, Pecjak, Siner, Yan Kulesza, Motyka, Stebel, Theeuwes link to parton showers: amc@nlo, Powel Frederix et al. Garzelli, Kardos, Papadopoulos, Trócsányi important work on backrounds t tb b, t tjj, etc. Bredenstein, Denner, Dittmaier, Pozzorini Bevilacqua, Czakon, Papadopoulos, Pittau, Worek Cascioli, Maierhofer, Pozzorini Openloops + Sherpa

13 0 TeV: top densities? t t t t NLO exact t t splittin & mass/off-shell effects no resummation of lom 2 /m2 t terms NNLO massless/on-shell t s, no p Tt resummation of lom 2 /m2 t terms typical transverse scale small: m 2 t +p2 Tt > m 2 t no lare los, no resummation no top PDFs Maltoni, Ridolfi, Ubiali

14 IV CONCLUSIONS is boson searches/studies at LC belon to major endeavours most QCD and elw. corrections known < LC several dedicated O tools available for SM [MSSM, NMSSM,...] important to develop NLO event enerators [ backrounds]

15 BACKU P SLIDES

16 (vi) is pair production 00 σ(pp + X) [fb] M = 125 GeV NNLO QCD 0 NLO QCD NLO QCD NNLO QCD qq qq qq/ t t q q W q q Z s [TeV] Balio, Djouadi, Quevillon

17 t, b λ + t, b t, b c tt/bb threshold reion: sensitive to λ lare M : sensitive to c tt/bb [e.. boosted is pairs] 00 0 qq qq σ(pp +X) [fb] s = 14 TeV, M = 125 GeV : σ σ λ λ [decreasin with M 2 ] 1 q q W q q Z λ /λ SM Balio, Djouadi, Gröber, Mühlleitner, Quevillon, S.

18 SM t, b λ + t, b + third eneration dominant t,b 3 2-loop QCD corrections: 90 0% [M 2 4m2 t, µ = M ] K(pp +X) s=14 TeV µ 2 = M 2 = Q 2 m t = 175 GeV K tot φ 1 φ 1 φ φ, Z 1 K φ 2 φ 2 φ K virt φ 1 q q 0 K qq K q φ 1 φ φ 2 φ 2 φ 2 M [GeV] Dawson, Dittmaier, S.

19 2-loop QCD corrections: σ = σ 0 + σ 1 m 2 t + + σ 4 m 8 t Grio, off, Melnikov, Steinhauser NLO mass NLO in real corrections: % Frederix, Frixione, irschi, Maltoni, Mattelaer, Torrielli, Vryonidou, Zaro sizeable virtual mass effects K NNLO QCD corrections: 20% [M 2 4m2 t ] de Florian, Mazzitelli Grio, Melnikov, Steinhauser s cut (GeV) dσ dq fb GeV % NNLO NLO LO soft luon resummation: % Q GeV [M 2 4m2 t ] Shao, Li, Li, Wan de Florian, Mazzitelli

20 Full NLO calculation: top only Numerical interation, sector decomposition, contour deformation 6% 20% Borowka, Greiner, einrich, Jones, Kerner, Schlenk, Schubert, Zirke Balio, Campanario, Glaus, Mühlleitner, S., Streicher (in preparation) 13 TeV: σ NLO = 27.80(8) +13.8% 12.8% fb σnlo EFT = % 15% fb -13.7% mass effects NLO + NNLO differential Grazzini, einrich, Jones, Kallweit, Kerner, Lindert, Mazzitelli