New physics effects in Higgs cross sections

Transcription

1 New physics effects in Higgs cross sections Robert Harlander Bergische Universität Wuppertal ERC Workshop Nov 2014, Mainz supported by

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3 rescaled couplings new Higgs bosons BSM particle effects new processes

4 Gluon fusion (pp H+X) [pb] pp H (NNLO+NNLL QCD + NLO EW) pp qqh (NNLO QCD + NLO EW) pp WH (NNLO QCD + NLO EW) pp ZH (NNLO QCD +NLO EW) pp tth (NLO QCD) s= 8 TeV M H [GeV] LHC HIGGS XS WG 2012 NLO: Spira, Djouadi, Graudenz, Zerwas 91, 93 Dawson 91 NNLO: Resummation: RH, Kilgore 02 Anastasiou, Melnikov 02 Ravindran, Smith, v. Neerven 03 Catani, de Florian, Grazzini, Nason 02 Ahrens, Becher, Neubert, Zhang 08 Electroweak: Actis, Passarino, Sturm, Uccirati 08 Aglietti, Bonciani, Degrassi, Vicini 04 Degrassi, Maltoni 04 Djouadi, Gambino 94 ~5% Fully differential NNLO: ~80% Mixed EW/QCD: Anastasiou, Boughezal, Petriello 09 Anastasiou, Melnikov, Petriello 04 Catani, Grazzini 07 ~30% ~10%

5 Gluon fusion (pp H+X) [pb] pp H (NNLO+NNLL QCD + NLO EW) pp qqh (NNLO QCD + NLO EW) pp WH (NNLO QCD + NLO EW) pp ZH (NNLO QCD +NLO EW) pp tth (NLO QCD) s= 8 TeV M H [GeV] LHC HIGGS XS WG 2012 NLO: Spira, Djouadi, Graudenz, Zerwas 91, 93 Dawson 91 NNLO: Resummation: RH, Kilgore 02 Anastasiou, Melnikov 02 Ravindran, Smith, v. Neerven 03 Catani, de Florian, Grazzini, Nason 02 Ahrens, Becher, Neubert, Zhang 08 Electroweak: Actis, Passarino, Sturm, Uccirati 08 Aglietti, Bonciani, Degrassi, Vicini 04 Degrassi, Maltoni 04 Djouadi, Gambino 94 ~5% Fully differential NNLO: ~80% heavy-top limit! Mixed EW/QCD: Anastasiou, Boughezal, Petriello 09 Anastasiou, Melnikov, Petriello 04 Catani, Grazzini 07 ~30% ~10%

6 heavy-top effective theory: t t t H m t M H C(mt, α s ) H σ(pp H+X)[pb] NLO, LHC HIGLU M H [GeV]

7 heavy-top effective theory: t t t H m t M H C(mt, α s ) H σ(pp H+X)[pb] 10 NLO, LHC HIGLU σ HO σ LO (m t ) ( σ HO σ LO ) m t M H [GeV]

8 heavy-top effective theory: t t t H m t M H C(mt, α s ) H σ(pp H+X)[pb] 10 NLO, LHC HIGLU σ HO σ LO (m t ) ( σ HO σ LO ) m t 1 what about higher orders? M H [GeV]

9 Heavy-top limit: σ HO (s, m H, m t ) σ LO (m t, m H ) ( σ HO ) (s, m H ) σ LO m t Honest expansion: σ HO (s, m H, m t )= n ( m 2 H 4m 2 t ) n σ HO n (s, m H )

10 Heavy-top limit: σ HO (s, m H, m t ) σ LO (m t, m H ) ( σ HO ) (s, m H ) σ LO m t Honest expansion: σ HO (s, m H, m t )= n ( m 2 H 4m 2 t ) n σ HO n (s, m H ) ok for virtual:

11 Heavy-top limit: σ HO (s, m H, m t ) σ LO (m t, m H ) ( σ HO ) (s, m H ) σ LO m t Honest expansion: σ HO (s, m H, m t )= n ( m 2 H 4m 2 t ) n σ HO n (s, m H ) ok for virtual: problem for real, because s > 4 mt 2 possible:

12 !^ gg /! 0 1/m t 0 σ = φ φ σˆ x = m 2 H /ŝ

13 !^ gg /! 0 1/m t x = m 2 H /ŝ

14 !^ gg /! 0 1/m t 0 1/m t x = m 2 H /ŝ

15 !^ gg /! 0 1/m t 0 1/m t 2 1/m t 4 1/m t x = m 2 H /ŝ

16 !^ gg /! 0 1/m t 0 1/m t 2 1/m t 4 1/m t 6 threshold x = m 2 H /ŝ

17 parton luminosity gg /! 0 50 M 40 H =130GeV 4 2 1/m 1/m t t qg /m t !^ 6 1/m t gg threshold -10 qq qq -20 qq x = mh 2 /ŝ parton M H = qq qq qq 10 (a)

18 !^ gg /! /m 1/m t t 0 1/m t [Marzani et al 08] 1/m t 6 threshold x = m 2 H /ŝ

19 !^ gg /! /m 1/m t t 0 1/m t (σ = φ φ σ) ˆ 1/m t 6 threshold 10 0 soft exp x = m 2 H /ŝ (BergischeUniversitätWuppertal) Top Mass effects in gg H Oct / 27

20 ! gg (M t n ) /! HIGLU gg exact n=0,2,4,6,8,10 NLO, 14 TeV M H / GeV

21 1.1! NNLO /! NNLO eff TeV 1/M t n, n=0,...,6 σ NNLO eff σ LO (m t ) ( σ NNLO σ LO ) m t RH, Mantler, Marzani, Ozeren 09 Pak, Rogal, Steinhauser M H /GeV

22 Differential e.g. inclusive H+jet: LO [! "1jet ] 1 k mt [pb] Top Expansion O(1 m t0 ) + O(1 m t2 ) + O(1 m t4 ) exact unmatched s = 13TeV jet p T,min [GeV]

23 Differential e.g. inclusive H+jet: σ NLO tot, matched LO [! "1jet ] 1 k mt [pb] jet, matched σ LO m k t σ NLO m k t tot, unmatched Top Expansion O(1 m t0 ) + O(1 m t2 ) + O(1 m t4 ) exact m k t = σ 1-jet, LO unmatched unmatched s = 13TeV σ 1-jet, LO matched m k t jet p T,min + [GeV] m k t σtot, NLO matched m k t σ 1-jet, LO unmatched m k t σtot, NLO unmatched m k t Neumann, Wiesemann 14

24 Differential e.g. inclusive H+jet: LO [! "1jet ] 1 k mt [pb] Top Expansion O(1 m t0 ) + O(1 m t2 ) + O(1 m t4 ) exact unmatched s = 13TeV jet p T,min [GeV] Neumann, Wiesemann 14

25 Differential e.g. inclusive H+jet: LO [! "1jet ] 1 k mt [pb] Top Expansion O(1 m t0 ) + O(1 m t2 ) + O(1 m t4 ) exact matched s = 13TeV jet p T,min [GeV] Neumann, Wiesemann 14

26 @ NLO NLO [! "1jet ]1 k mt [pb] Top Expansion O(1 m t0 ) + O(1 m t2 ) + O(1 m t4 ) unmatched s = 13TeV jet p T,min [GeV]

27 @ NLO NLO [! "1jet ]1 k mt [pb] Top Expansion O(1 m t0 ) + O(1 m t2 ) + O(1 m t4 ) matched s = 13TeV jet p T,min [GeV]

28 !^ gg /! /m 1/m t t 0 1/m t (σ = φ φ σ) ˆ 1/m t 6 threshold 10 0 soft exp x = m 2 H /ŝ (BergischeUniversitätWuppertal) Top Mass effects in gg H Oct / 27

29 !^ gg /! /m 1/m t t 0 1/m t (σ = φ φ σ) ˆ 1/m t 6 Effect of higher threshold dimensional operators! 10 0 soft exp x = m 2 H /ŝ (BergischeUniversitätWuppertal) Top Mass effects in gg H Oct / 27

30 Consider extreme case: Higgs does not couple to top quark gluon-higgs coupling mediated by Λ >> MH

31 Consider extreme case: Higgs does not couple to top quark gluon-higgs coupling mediated by Λ >> MH L = C 1 Λ O n=2 C n Λ 3 O n

32 Consider extreme case: Higgs does not couple to top quark gluon-higgs coupling mediated by Λ >> MH L = C 1 Λ O n=2 C n Λ 3 O n measurement of total cross section at least one of the Cn must be large! expect very different pt spectrum see also: RH, Neumann 13 Banfi, Martin, Sanz 14 Azatov, Paul 14 Grojean, Salvioni, Schlaffer, Weiler 14

33 pt-shape for higher operators: gg gq qq sum 10!2 1 " i,j # $" i,j $p T [1/GeV] 10!3 10!4 10!5 10!6 Operator O 1 2 O 1 O 2 O 1 O 3 O 1 O 5 SM p T [GeV] NLO: RH, Neumann 13 Dawson, Lewis, Zeng 14

34 rescaled couplings new Higgs bosons BSM particle effects new processes

35 Rescaling of couplings:

36 Rescaling of couplings:

37 Rescaling of couplings: sin(β α) cos(β α)

38 Effects due to new Higgs bosons:

39 Effects due to new Higgs bosons:

40 Effects due to new Higgs bosons: small, but: new s-channel contribution!

41 Effects due to new Higgs bosons: small, but: new s-channel contribution! only for ZH, not WH!

42 WH vs. (a) ZH in M H the [GeV] SM: (b) M H [GeV] "(pp "(pp!! WH) ZH) NNLO NLO / LO s = 14 TeV NLO NNLO / LO / LO (± (± 1") 1") NLO NNLO / LO / LO (± (± 2") 2") LHC HIGGS XS WG 2010 "(pp! ZH) NNLO / LO s = 14 TeV NNLO / LO (± NNLO / LO (± 1") 2") LHC HIGGS XS WG (c) (d) M H [GeV] M H Fig. 11: K-factors (ratio to LO prediction) for the NLO and NNLO cross sections of Fig. 10. (d) M H [GeV] 33

43 WH vs. (a) ZH in M H the [GeV] SM: (b) M H [GeV] "(pp "(pp!! WH) ZH) NNLO NLO / LO s = 14 TeV NLO NNLO / LO / LO (± (± 1") 1") NLO NNLO / LO / LO (± (± 2") 2") LHC HIGGS XS WG 2010 "(pp! ZH) NNLO / LO s = 14 TeV NNLO / LO (± NNLO / LO (± 1") 2") LHC HIGGS XS WG (c) (d) M H [GeV] M H Fig. 11: K-factors (ratio to LO prediction) for the NLO and NNLO cross sections of Fig. 10. (d) M H [GeV] 33

44 at NLO: NLO: Altenkamp, Dittmaier, RH, Rzehak, Zirke 12

45 at NLO: σ(gg HZ + X)[fb] S = 14 TeV LO NLO NLO+NLL m µ =(p H + p Z ) 2 H = 125 GeV NLO+NLL: RH, Kulesza, Theeuwes, Zirke 14 NLO: Altenkamp, Dittmaier, RH, Rzehak, Zirke 12

46 in SUSY?

47 in SUSY? enhancement by tanβ

48 in SUSY? enhancement by tanβ

49 in SUSY? enhancement by tanβ Squarks?

50 in SUSY? enhancement by tanβ Squarks? + = 0

51 in SUSY? enhancement by tanβ Squarks? only + = 0

52 consider ratio: σwh/σzh

53 consider ratio: σwh/σzh very weak dependence on PDFs very weak dependence on αs reduced experimental uncertainties

54 consider ratio: σwh/σzh very weak dependence on PDFs very weak dependence on αs reduced experimental uncertainties 2HDM RH, Liebler, Zirke 13 see also: Englert, McCullough, Spannowsky 13

55 rescaled couplings new Higgs bosons BSM particle effects new processes

56 +

57 + can interfere distructively (gluophobic Higgs) Djouadi 98

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59 full NLO NNLO 2HDM bbh various ren. schemes link to FeynHiggs link to LHAPDF link to 2HDMC... RH, Liebler, Mantler 12

60 Bagnaschi, RH, Liebler, Mantler, Slavich, Vicini 14

61 squark effects:

62 mb(mh/2) vs. mb(pole) in Yukawa coupling

63 Transverse momentum distribution: + small pt region: factorization for pt>mb?

64 Transverse momentum: Bagnaschi, Degrassi, Slavich, Vicini 11 Mantler, Wiesemann 12 Grazzini, Sargsyan 13 + see also: Banfi, Monni, Zanderighi 14

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66 dp 2 T [ dσ dp 2 T ] f.o.+l.a. [σ tot ] f.o.. Bozzi, Catani, de Florian, Grazzini 14

67 dp 2 T [ dσ dp 2 T ] f.o.+l.a. [σ tot ] f.o.. Bozzi, Catani, de Florian, Grazzini 14 may lead to dσ/dpt dσ/dpt fixed order at large pt

68 2 2 (d res /dp T ) / (d fo /dp T ) Q res = 94 GeV Q res = 96 GeV Q res = 98 GeV Q res = 100 GeV Q res = 102 GeV (d res /dp T ) / (d fo /dp T ) Q res = 42 GeV Q res = 44 GeV Q res = 46 GeV Q res = 48 GeV Q res = 50 GeV p T [GeV] (a) p T [GeV] (b) 2 (d res /dp T ) / (d fo /dp T ) Q res = 64 GeV Q res = 66 GeV Q res = 68 GeV Q res = 70 GeV Q res = 72 GeV RH, Mantler, Wiesemann p T [GeV] (c)

69 RH, Mantler, Wiesemann 14

70 rescaled couplings new Higgs bosons BSM particle effects new processes

71 New production modes:

72 New production modes:

73 New production modes:

74 4FS: through NLO 5FS: through NNLO

75 4FS: through NLO 5FS: through NNLO not in 5FS NNLO!

76 4FS: through NLO 5FS: through NNLO not in 5FS NNLO! not in 4FS NLO!

77 4FS: through NLO 5FS: through NNLO not in 5FS NNLO! not in 4FS NLO! Santander matching RH, Krämer, Schumacher 11 see also: Maltoni, Ridolfi, Ubiali 12 Wiesemann et al. 14

78 Total cross section: 10 3!(pp " bb _ h + X) [fb] #s = 14 TeV µ = (2m b + M h )/ bb _ " h (NNLO) 10 gg " bb _ h (NLO) M h [GeV] Les Houches X at the Tevatron and the LHC as a function of the Higgs mass M h with bands correspond to varyingthescalefromµ R = µ F =(2m b + M h )/8 to esarefromref.[10].

79 pt distribution at NNLO+NNLL in 5FS: RH, Tripathi, Wiesemann 14

80 4FS vs. 5FS M. Wiesemann a, R. Frederix b, S. Frixione b, V. Hirschi c, F. Maltoni d,p.torrielli ae 2014

81 4FS vs. 5FS Figure 15: Rapidity of the hardest (left panel) and second-hardest (right panel) B hadron, in the 4FS and 5FS at the NLO+PS accuracy, as predicted by Herwig++ and Pythia8. All histograms have been normalised so that their integrals are equal to one. M. Wiesemann a, R. Frederix b, S. Frixione b, V. Hirschi c, F. Maltoni d,p.torrielli ae 2014

82 Conclusions SM results often allow trivial estimate of BSM effects dedicated BSM cross section predictions require fast and flexible tools SusHi for gluon fusion for SUSY Higgs Strahlung: high potential due to WH vs. ZH 4FS vs. 5FS (6FS??) may become very relevant very promising: differential quantities