EFT: the analysis approach and implementation in generators. Cen Zhang

Transcription

1 EFT: the analysis approach and implementation in generators Cen Zhang CERN Jan

2 Implementation status, UFO, MG5, Sherpa, Whizard. (Thank Silvan Kuttimalai and Jürgen Reuter) Available UFO models, results, etc NLO status with MG5, HC and top-eft. Summary

3 Approach SM Lagrangian supplemented with DIM-6 operators (hence SMEFT) L EFT = L SM + X C i O i 2 i The physics goal is to determine the SM Lagrangian at Dim-6. Determining the operators for measurements makes sense only if a GLOBAL STRATEGY is used. Ideally the following should be done: Assume all ops might NOT be zero at the measured scale. Identify operators entering each observables. Find enough observables to constrain all ops. Calculate observables. - where we need tools Solve the system. cf. ATL-PHYS-PUB

4 Status summary

5 EFT with MG5 Simply follow: FeynRules->UFO->MG5 All higher-dimensional Lorentz structures are supported in UFO. [ Degrande et al.] ALOHA translates Lorentz structures in UFO to helicity amplitude subroutines. [ de Aquino et al.] In principle this is it. (At LO) all you can do with the SM can be done with higherdim operators. Except dynamical scales At you can find a list of EFT models ready for use.

6 EFTs with Sherpa Silvan Kuttimalai Institute for Particle Physics Phenomenology, Durham

7 EFTs with UFO and Sherpa [arxiv: ] UFO-support Fully Automatized via Python Extension I I I I I I Loads UFO model Writes out a C++ model Writes out C++ routines for arbitrary Lorentz structures Compiles everything, installs library to be loaded at runtime Once installed, model is available for event generation Use identical model and parameter input as e.g. MadGraph EFTs with UFO+Sherpa I I I FeynRules/UFO accommodates very generic interactions Any EFT implemented in FeynRules/UFO can be simulated with Sherpa Arbitrary higher dimensional (EFT-) operators supported

8 EFTs with UFO and Sherpa [arxiv: ] UFO Support Seamlessly Integrated with Framework I I I High multiplicity tree-level MEs with Comix for hard scattering Fully automatized spin-correlated decay chains Events can be showered and hadronized as usual Example: MSSM Decays d 0 1 µ + PDF BSM BSM PDF 1/s ds/dm [10 3 /GeV] ũ + 1 Full ME Correlated decays Uncorrelated decays W + µ Sherpa MC 1 MI p corr full d 2 (corr)+d 2 (full) m(d, µ + ) [GeV]

9 EFTs with UFO and Sherpa [arxiv: ] UFO Support Seamlessly Integrated with Framework I I I High multiplicity tree-level MEs with Comix for hard scattering Fully automatized spin-correlated decay chains Events can be showered and hadronized as usual BSM Current Development BSM I First EFT applications with tree-level merging PDF PDF I First steps towards fixed-order NLO with OpenLoops MI

10 EFT with Whizard (Thank Jürgen Reuter) Complete SM EFT at Dim-6 implemented in v2.2.8, in the Warsaw basis.

11 EFT with Whizard (Thank Jürgen Reuter) Complete SM EFT at Dim-6 implemented in v2.2.8, in the Warsaw basis. [B. Grzadkowski et al, 2010]

12 EFT with Whizard (Thank Jürgen Reuter) Complete SM EFT at Dim-6 implemented in v2.2.8, in the Warsaw basis. Some Dim-8 operators are available (quartic weak-boson couplings).

13 EFT with Whizard (Thank Jürgen Reuter) Complete SM EFT at Dim-6 implemented in v2.2.8, in the Warsaw basis. Some Dim-8 operators are available (quartic weak-boson couplings). [ ]

14 EFT with Whizard (Thank Jürgen Reuter) Complete SM EFT at Dim-6 implemented in v2.2.8, in the Warsaw basis. Some Dim-8 operators are available (quartic weak-boson couplings). Automated interfaces to FeynRules and SARAH.

15 EFT with Whizard (Thank Jürgen Reuter) Complete SM EFT at Dim-6 implemented in v2.2.8, in the Warsaw basis. Some Dim-8 operators are available (quartic weak-boson couplings). Automated interfaces to FeynRules and SARAH. UFO not yet supported but in progress. (at latest in summer.)

16 UFO examples That are: publicly available validated ready for simulation

17 Multi-vector boson Dim-6 TGC: UFO and VBFNLO UFO model: EWdim6 [arxiv: , Degrande, Greiner, Kilian, Mattelaer, Mebane, Stelzer, Willenbrock, CZ] CP-even CP-odd

18 Multi-vector boson Dim-6 TGC: UFO and VBFNLO UFO model: EWdim6 [arxiv: , Degrande, Greiner, Kilian, Mattelaer, Mebane, Stelzer, Willenbrock, CZ] CP-even CP-odd Dim-8 QGC: UFO, Whizard, VBFNLO pp>w + W + jj [ , C. Degrande et al.]

19 Top EFT

20 Top EFT

21 Top EFT [ Perello Rosello, Vos]

22 Higgs Eff. Lagrangian

23 [arxiv: , Alloul, Fuks, Sanz] [arxiv: , Contino et al.] 33 CP-even + 6 CP-odd 34 operators relevant for Higgs Flavor-universal SILH: hep-ph/ , Guildice et al. F1: W/Z to ffbar (V/A) F2: EW/chromo-dipoles G: Gauge-boson self interaction (4-fermions are not included)

24 HEL in Higgs Fits see also [ Englert, Kogler, Schulz, Spannowsky] [ , Ellis, Sanz, You] Higgs, TGC, combination Current, 300fb -1,3000fb -1 TGC not included

25 EW sector probed by PEWM+TGC+Higgs: PEWM assuming flavor symmetry (+) 2. TGC (and Higgs) 3. New from Higgs (-) W-pair production: g Z 1, apple, Z Mainly from Z-pole: only 8 d.o.f (10 would appear in BW/Warsaw) [A. Falkowski and F. Riva 2014]

26 HEL in Top Fits [ , Tonero and Rosenfeld] ttz+ttw Top dipole fits

27 and many more Check the FeynRules model database E.g. ntgc: dim-8 operators affecting neutral triple gauge boson couplings [C. Degrande] Higgs Characterisation: [F. Demartin, K. Mawatari] spin/parity characterisation of the 125 GeV scalarresonance. Higgs basis [B. Fuks, K. Mawatari] There are also some top- and Higgs-FCNC models Also check Rosetta: an operator basis translator for SM EFT (Warsaw, SILH, Higgs basis, ) [ , Falkowski et al.]

28 Going to NLO in QCD with EFT

29 With all we need for NLO is the Dim-6 UV and R2 counterterms. UV CT characterize the RG running & mixing of operators. R2 occurs due to numerical techniques only evaluate 4-dimensional part of loop amplitude (while we need D-dimensional) NLOCT is being developed to incorporate both at Dim-6, in an automatic way. Alternatively, there are case studies, not fully automated. For example, can take UV CTs from [ Alonso et al.] Several NLO UFOs have been made available. [C. Degrande 2014] Higgs Characterisation [P. Artoisenet et al. 2013] [F. Demartin et al. 2014] [F. Demartin et al. 2015] NLO in progress (Degrande, Fuks, Mawatari, Mimasu, Sanz) Top EFTs (Bylund, Degrande, Franzosi, Maltoni, Tsinikos, Vryonidou, CZ) Color Neutral ops trivial to add (TGC, DM with vectors, etc.)

30 Higgs Characterisation [P. Artoisenet et al. 2013] [F. Demartin et al. 2014] [F. Demartin et al. 2015]

31 Higgs Characterisation [P. Artoisenet et al. 2013] [F. Demartin et al. 2014] [F. Demartin et al. 2015] On going developments: HEL at NLO (Degrande, Fuks, Mawatari, Mimasu, Sanz)

32 Top EFT Flavorconserving Flavorchanging (neutral) We aim to provide: (in particular for experimentalists) A framework for testing top-quark couplings, with QCD NLO accuracy. i.e. all TH inputs for an NLO global fit will be automated.

33 Flavorconserving Flavorchanging (neutral)

34 Decays and FCNC direct t production is available analytically. [ CZ], [ F. Maltoni, CZ], [hep-ph/ J.J.Liu et al.] Flavorconserving Flavorchanging (neutral)

35 Decays and FCNC direct t production is available analytically. [ CZ], [ F. Maltoni, CZ], [hep-ph/ J.J.Liu et al.] FCNC associated productions have been implemented. [ Degrande, Maltoni, Wang, CZ] Flavorconserving Flavorchanging (neutral)

36 Top-FCNC operators available at

37 Decays and FCNC direct t production is available analytically. [ CZ], [ F. Maltoni, CZ], [hep-ph/ J.J.Liu et al.] FCNC associated productions have been implemented. [ Degrande, Maltoni, Wang, CZ] Flavorconserving Flavorchanging (neutral)

38 Decays and FCNC direct t production is available analytically. [ CZ], [ F. Maltoni, CZ], [hep-ph/ J.J.Liu et al.] FCNC associated productions have been implemented. [ Degrande, Maltoni, Wang, CZ] Flavorconserving Flavorchanging (neutral) First automation in flavor-conserving case: ttbar with chromo-dipole [ D.B. Franzosi, CZ]

39 Decays and FCNC direct t production is available analytically. [ CZ], [ F. Maltoni, CZ], [hep-ph/ J.J.Liu et al.] FCNC associated productions have been implemented. [ Degrande, Maltoni, Wang, CZ] Flavorconserving Flavorchanging (neutral) First automation in flavor-conserving case: ttbar with chromo-dipole [ D.B. Franzosi, CZ] Complete top-ew operators: almost done [Bylund, Maltoni, Tsinikos, Vryonidou, CZ]

40 Top-EW operators OtG, OtW, OtB mixing ttbar+v ttbar single top cf. [ , Rontsch and Schulze]

41 Operator fit with NLO xsecs: improved limits NLO LO Decay NLO LO H3L C fq C tw H1,3L C qq

42 3 Operator fit with NLO xsecs: improved limits H3L CfQ Corrections on on distributions can be important dσ σ dy 0.25 NLO 3 2 LO 2 NLO 1 Decay 1 LO t-channel single top LHC13, (N)LO+PYTHIA t 0.2 CtW dσ σ dp [GeV-1] H1,3L CqQ (3) t-channel single top LHC13, (N)LO+PYTHIA T,j 0.2 (3) 0.4 OφQ LO OφQ NLO OtW LO OtW NLO (3) (3) OφQ LO OφQ NLO OtW LO OtW NLO (3) OφQ NLO OtW 3 NLO y 1 t 2 LO LO (3) OφQ NLO LO OtW NLO LO MadGraph5_aMC@NLO 0 MadGraph5_aMC@NLO p T,j

43 Decays and FCNC direct t production is available analytically. [ CZ], [ F. Maltoni, CZ], [hep-ph/ J.J.Liu et al.] FCNC associated productions have been implemented. [ Degrande, Maltoni, Wang, CZ] Flavorconserving Flavorchanging (neutral) First automation in flavor-conserving case: ttbar with chromo-dipole [ D.B. Franzosi, CZ] Complete top-ew operators: almost done [Bylund, Maltoni, Tsinikos, Vryonidou, CZ]

44 Decays and FCNC direct t production is available analytically. [ CZ], [ F. Maltoni, CZ], [hep-ph/ J.J.Liu et al.] FCNC associated productions have been implemented. [ Degrande, Maltoni, Wang, CZ] Flavorconserving Flavorchanging (neutral) First automation in flavor-conserving case: ttbar with chromo-dipole [ D.B. Franzosi, CZ] Complete top-ew operators: almost done [Bylund, Maltoni, Tsinikos, Vryonidou, CZ] tth and thj: ongoing

45 Top-Higgs operators in progress chromo-dipole Yukawa gluon-higgs O tg = y t g s ( Q µ T A t) G µ O t = y 3 t ( ) Qt O G = y 2 t ( )G A µ G Aµ = 2 s A SM, LO c =0.25 LO tg pp tth at LHC13 (N)LO (Fixed order) Λ=1 TeV SM, NLO =0.25 NLO c tg (very preliminary) tth at LHC 13 TeV [pb/gev] H [in fb] dσ/dpt pt [GeV] H MadGraph5_aMC@NLO

46 Decays and FCNC direct t production is available analytically. [ CZ], [ F. Maltoni, CZ], [hep-ph/ J.J.Liu et al.] FCNC associated productions have been implemented. [ Degrande, Maltoni, Wang, CZ] Flavorconserving Flavorchanging (neutral) First automation in flavor-conserving case: ttbar with chromo-dipole [ D.B. Franzosi, CZ] Complete top-ew operators: almost done [Bylund, Maltoni, Tsinikos, Vryonidou, CZ] tth and thj: ongoing

47 Decays and FCNC direct t production is available analytically. [ CZ], [ F. Maltoni, CZ], [hep-ph/ J.J.Liu et al.] FCNC associated productions have been implemented. [ Degrande, Maltoni, Wang, CZ] Flavorconserving Flavorchanging (neutral) First automation in flavor-conserving case: ttbar with chromo-dipole [ D.B. Franzosi, CZ] Complete top-ew operators: almost done [Bylund, Maltoni, Tsinikos, Vryonidou, CZ] tth and thj: ongoing Four fermion operators are planned

48 Summary EFT models are available in several MC tools. In particular the UFO interface provides full support for arbitrary effective vertices. UFO models are publicly available Ongoing developments at NLO with MG5, including Higgs characterisation, HEL, top EFT, etc., and eventually full can be expected.

49 Backups

50 EFT approach to BSM Instead of looking for new particles, EFT focus on new interactions (of the SM particles). SM is the most general Lagrangian at DIM-4. To look for something new, we go to DIM-6. SM Lagrangian supplemented with DIM-6 operators (hence SMEFT) L EFT = L SM + X i C i O i 2 35

51 Basis EW-Higgs operators: a comparison [S. Willenbrock and CZ 2014] Warsaw/BW/Standard HISZ SILH/GGPR O W = IJK Wµ I W J W Kµ O WWW =Tr[Ŵµ Ŵ Ŵ µ ] O 3W = 1 3! g abcwµ a W W b c µ O 'W = ' 'Wµ W I Iµ O WW = Ŵ µ Ŵ µ O 'B = ' 'B µ B µ O BB = ˆBµ ˆBµ O BB = g 02 H 2 B µ B µ O 'W B = ' I 'Wµ B I µ O BW = ˆBµ Ŵ µ O W =(D µ ) Ŵ µ (D ) O HW = ig(d µ H) a (D H)Wµ a O B =(D µ ) ˆBµ (D ) O HB = ig 0 (D µ H) (D H)B µ O DW =Tr [D µ, Ŵ ][D µ, Ŵ ] O 2W = 1 2 Dµ Wµ a 2 O DB = g02 2 (@ µb )(@ µ B ) O 2B = 1 2 (@µ B µ ) 2 O W = ig 2 H a D! µ H D Wµ a O B = ig0 2 H D! µ B µ O 'D = ' D µ ' ' D µ ' O,1 =(D µ ) (D µ ) O T = 1 2 H D! 2 µ H O ' =(' ') (' ') O,2 = 1 µ( )@ µ ( ) O H = 1 2 (@µ H 2 ) 2 3 O ' =(' ') 3 O,3 = 1 3 O 6 = H 6 O,4 =(D µ ) (D µ )( )

52 EOM can be applied in both directions Warsaw/BW basis: Bosonic->Fermionic Universal for 3 generations. Convenient for RG. HISZ, SILH, EGGM: Fermionic->Bosonic: Eliminiate Convenient for PEWM, TGC, and Higgs 2 flat directions in PEWM become more transparent 3 TGC couplings directly related to 3 operators

53 EOM can be applied in both directions Gauge boson+higgs with Fermions, summed over 3 generations Warsaw/BW basis: Bosonic->Fermionic Universal for 3 generations. Convenient for RG. HISZ, SILH, EGGM: Fermionic->Bosonic: Eliminiate Convenient for PEWM, TGC, and Higgs 2 flat directions in PEWM become more transparent [A. Falkowski and F. Riva 2014] [C. Grojean et al. 2006] 3 TGC couplings directly related to 3 operators

54 2 flat directions in PEWM in Warsaw/BW Z-pole data involve 10 operators However, only 8 are really constrained. Thus 2 directions are weakly constrained e.g., when marginalizing over other operators, i.e. a factor of ~2500 weaker. Becomes ~10 in one of the bosonic bases.

55 2 flat directions in PEWM in Warsaw/BW Z-pole data involve 10 operators O l, O (3) l, O e, O Q, O (3) Q, O u, O d, O ll, O WB, O (3) However, only 8 are really constrained. [A. Falkowski and F. Riva 2014] Thus 2 directions are weakly constrained [C. Grojean et al. 2006] e.g., when marginalizing over other operators, S =0.05 ± 0.10, T = 0.04 ± 0.10 ) S = 53 ± 250, T = 36 ± 223 i.e. a factor of ~2500 weaker. [B. Grinstein et al. 2013] Becomes ~10 in one of the bosonic bases.

56 O l, O (3) l, O e, O Q, O (3) Q, O u, O d, O ll, O WB, O (3) It is incorrect ignore all these operators, just because they are constrained by precision EW tests.

57 O l, O (3) l, O e, O Q, O (3) Q, O u, O d, O ll, O WB, O (3) It is incorrect ignore all these operators, just because they are constrained by precision EW tests. TGC also look more transparent in SILH/HISZ bases Traditionally uses g Z 1, apple, Z In Warsaw/BW basis, only OBW and O3W enters directly. Remaining degree of freedom comes from shifting input parameters. In SILH basis, TGC are directly given by O HW + O HB, O W O B + O HW O HB, O 3W

58 Cross sections at LHC 13 single top = SM + C i TeV 2 ttbar+v 2 (1) i + O( 4 ) (1) NLO σ i /σ SM (1) NLO σ i /σ SM t-ch. LO tt+z LO 1 10 t-ch. NLO 1 10 tt+z NLO t+w LO t+w NLO s-ch. LO tt+γ LO tt+γ NLO tt LO s-ch. NLO 2 10 tt NLO O O (3) (1) O tw σ (NLO) i tg φq (1) 1.4 σ i (LO) 1.2 σ NLO t-ch. NLO σ t+w σ NLO s-ch. =217 pb =73.4 pb =10.1 pb (3) (1) σ i O φq (1) O (NLO) 1.4 σ i (LO) (1) φq Oφ t OtW OtB OtG σnlo =0.885 pb ttz NLO σ ttγ =2.73 pb σ NLO =767 pb tt 1 O (3) φq OtW OtG 1 (3) O φq O (1) φq Oφt OtW OtB OtG

59 TGC fit, with W-pair production, plus Higgs data Higgs is the new tool to precision EW physics [A. Falkowski et al. 2015]

60 TGC fit, with W-pair production, plus Higgs data Higgs is the new tool to precision EW physics [A. Falkowski et al. 2015] Combined fit for Higgs op. [J. Ellis et al. 2014] Signal-strength data combined with TGC (Higgs, TGC, combination) See also [A. Falkowski, F. Riva 2014] [A. Pomarol, F. Riva 2013] [T. Corbett et al. 2015] [T. Corbett et al. 2013] [H. Belusca-Maito 2014] and many others

61 Top fit: FCNC (at NLO) [ Durieux, Maltoni, CZ]

62 [ Durieux, Maltoni, CZ] Top fit: FCNC (at NLO) Top fit: flavor conserving [ A. Buckley, et al.]