Higgs production on Vector Boson Fusion at NNLO QCD in NNLOjet Juan M Cruz-Martinez in collaboration with: T. Gehrmann, N. Glover, A. Huss arXiv:1802.02445 IPPP Durham University HL-HE LHC Workshop Juan Cruz-Martinez (IPPP) VBF H in NNLOjet 1 / 6
Vector Boson Fusion amplitudes We work on what is usually known as the DIS approach, which means defining “Vector Boson Fusion” as: Diagrams in which the vector boson is exchanged in the t channel Not including exchange of gluons between upper and lower legs (either real or virtual). Not including same flavour quark annihilation These contributions are estimated to be negligible when VBF cuts are applied 1 . 1 See, for instance arXiv:1802.09955 Juan Cruz-Martinez (IPPP) VBF H in NNLOjet 2 / 6
Current status We re-implemented all Matrix Elements necessary for the DIS approximation, ie, forbidding colour flow between the two legs. We use Antenna Subtraction to control divergences. Implemented in NNLOjet , which provides all analysis routines, antenna functions and integration machinery. Results and plots from: arXiv:1802.02445 We find good agreement with arXiv:1506.02660v2, see backup slides / A. Karlberg talk. Juan Cruz-Martinez (IPPP) VBF H in NNLOjet 3 / 6
Observables, VBF at NNLO NNLOJET NNLOJET ‾ ‾ NNLOJET NNLOJET ‾ ‾ VBF H 2j NNLO √ s √ s = 13 TeV = 13 TeV VBF H 2j NNLO √ s √ s = 13 TeV = 13 TeV 500 LO LO NLO NLO 400 NNLO NNLO 10 1 j 1 [fb/GeV] d σ /d Δ y jj [fb] 300 10 0 d σ /dp T 200 100 10 -1 0 Ratio to NLO Ratio to NLO 1.1 1.1 1 1 0.9 0.9 0.8 0.8 50 100 150 200 250 300 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 p T j 1 [GeV] Δ y jj Figure: For some observables the NNLO corrections alter the shape of the distributions, albeit their effect is much less than NLO. Juan Cruz-Martinez (IPPP) VBF H in NNLOjet 4 / 6
Observables, VBF at NNLO NNLOJET NNLOJET ‾ ‾ NNLOJET NNLOJET ‾ ‾ VBF H 2j NNLO √ s √ s = 13 TeV = 13 TeV VBF H 2j NNLO √ s √ s = 13 TeV = 13 TeV 1 LO 400 NLO 0.8 NNLO d σ /dM jj [fb/GeV] 300 d σ /d Φ j 12 [fb] 0.6 200 0.4 100 LO 0.2 NLO NNLO 0 0 Ratio to NLO Ratio to NLO 1.1 1.1 1 1 0.9 0.9 0.8 0.8 0 45 90 135 180 1000 2000 3000 4000 Φ j 12 [deg] M jj [GeV] Figure: For these observables we don’t see a change on the shape but the NNLO contributions falls consistently outside the NLO uncertainty bands. Juan Cruz-Martinez (IPPP) VBF H in NNLOjet 5 / 6
Future work Proper studies of Higgs production through the VBF production channel requires NNLO corrections. We have implemented NNLO QCD corrections to VBF Higgs alongside the other processes in NNLOjet . Other things we could add to our implementation include: Decay channels for the Higgs ( H → γγ , H → b ¯ b , H → WW ∗ ...). Multiple Higgs production (very small for 13 TeV, maybe relevant for high energies) Suggestions welcomed. Juan Cruz-Martinez (IPPP) VBF H in NNLOjet 6 / 6
Backup slides Juan Cruz-Martinez (IPPP) VBF H in NNLOjet 7 / 6
Vector Boson Fusion: VBF Cuts Two tagging jets with p T > 25 GeV Tagging jets in different hemisphere ( y 1 y 2 < 0) where each y i > 4 . 5 and ∆ y 12 > 4 . 5 �� M H � 2 0 ( p T , H ) = M H µ 2 + p 2 m jj > 600 GeV t , H 2 2 √ s = 13 TeV M H = 125 GeV � 1 � Scale variations corresponds to µ F = µ R = 2 , 1 , 2 µ 0 . PDF used: NNPDF30 nnlo as 0118 Juan Cruz-Martinez (IPPP) VBF H in NNLOjet 8 / 6
Total cross section with VBF cuts Comparison with 1506.02660v2 2 : σ 1506 . 02660 (fb) σ NNLOjet (fb) 957 +66 957 +66 LO − 59 − 59 876 +8 877 +7 NLO − 18 − 17 844 +8 844 +9 NNLO − 8 − 9 Table: Total cross section with VBF cuts. The errors correspond to a � 1 � scale variation of µ F = µ R = 2 , 1 , 2 µ 0 . We also find good agreement comparing differential distributions. 2 M.Cacciari, F.A.Dreyer, A.Karlberg, G.P.Salam and G.Zanderighi. “Fully Differential Vector-Boson-Fusion Higgs Production at Next-to-Next-to-Leading Order” PRL 115.082002 Juan Cruz-Martinez (IPPP) VBF H in NNLOjet 9 / 6
Recommend
More recommend
