NLO QCD+EW predictions for 2l2ν production

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1 NLO QCD+E predictions for 2l2ν production Marek Schönherr Universität ürich urich 8 May 207 Marek Schönherr NLO QCD+E predictions for 2l2ν production /20

2 NLO E corrections fixed-order next-to-leading order electroweak corrections MUNICH/SHERPA+OPENLOOPS for a range of processes: - pp V + 0,, 2(, 3) jets Lindert et.al. arxiv: FCC report, arxiv: E report arxiv: LH 5 arxiv: Kallweit,Lindert,Maierhöfer,Pozzorini,MS JHEP04(205)02, JHEP04(206)02 - pp t th LH 5 arxiv: pp j/pp j ratio LH 5 arxiv: Kallweit,Lindert,Maierhöfer,Pozzorini,MS arxiv: pp Vh FCC report, arxiv: pp 2l2ν Kallweit,Lindert,Pozzorini,MS, arxiv: SHERPA+RECOLA - pp V + 0,, 2 jets, pp 4l, pp t th Biedermann et.al. arxiv: dedicated comparisons in LH 5 against RECOLA ( + 2j) and MADGRAPH (t th) showed agreement Marek Schönherr NLO QCD+E predictions for 2l2ν production 2/20

3 Diboson production Kallweit, Lindert, Pozzorini, MS arxiv: NLO QCD+E calculation of DF and SF pp 2l2ν production ) pp e + µ ν ν Biedermann, et.al. JHEP06(206)065 DPA: Billoni, Dittmaier, Jäger, Speckner JHEP2(203)043 pp e + µ ν e ν µ at LO through photon induced processes contribute twice as much as c c-channel at LO to inclusive xs, more in TeV range, incl. at NLO E new 2) pp e + e ν ν new pp e + e ν e ν e at LO through and pp e + e ν µ/τ ν µ/τ at LO through contribution of ind. procs. depends very much on observable photon induced process included at NLO E all double-, single- and non-resonant diagrams included 4F to suppress single-top contribs at NLO QCD, jet veto to control large NLO QCD explore how NLO QCD E can be reproduced with current tools Marek Schönherr NLO QCD+E predictions for 2l2ν production 3/20

4 NLO E corrections Combination of QCD and E correction additive strict fixed order expansion dσ NLO QCD+E = dσ LO ( + δ QCD + δ E ) multiplicative contains terms of O(α S α) dσ NLO QCD E = dσ LO ( + δ QCD ) ( + δ E ) NLO E for photon initiated processes resolved final state photons should be renormalised on-shell (α(0)) absorbs IR divergences from f f splittings not included initial state (and unresolved final state) photons should be renormalised at the hard scale (α(m ), G µ, MS, etc.) match IR divergences in PDF evolution and collinear counter term Harland-Lang, Khoze, Ryskin Phys.Lett.B76(206)20-24 Kallweit, Lindert, Pozzorini, MS arxiv: Marek Schönherr NLO QCD+E predictions for 2l2ν production 4/20

5 Diboson production O(α 4 ) LO diagrams SF and DF ū d ν l ν l ν l u SF only Marek Schönherr NLO QCD+E predictions for 2l2ν production 5/20

6 Diboson production O(α 4 ) LO diagrams SF and DF ν l l ν l l l ν l SF only l Marek Schönherr NLO QCD+E predictions for 2l2ν production 6/20

7 Diboson production O(α 5 ) -loop diagrams SF and DF ū u d l l H l l SF only l ū u d l ū u d H l l Marek Schönherr NLO QCD+E predictions for 2l2ν production 7/20

8 Diboson production O(α 5 ) -loop diagrams SF and DF u,c,t u,c,t u,c,t d,s,b b,t b,t H b,t l l l l SF only =d,u,s,c,b,t b,t b,t H b,t l l l Marek Schönherr NLO QCD+E predictions for 2l2ν production 8/20

9 Diboson production,, O(α 5 ) real em. diagr. SF and DF, SF only similar ū u d u u u d u real emission corrections link - and -induced process contain singularities wrt. to both LO configuration once a PDF present, both channels have to be computed at NLO E, otherwise dependence on subtraction scheme contribution sizeable in TeV range without jet veto Marek Schönherr NLO QCD+E predictions for 2l2ν production 9/20

10 Diboson production DF pp e + µ νe νµ dσ/dpt [pb/gev] LO NLO QCD NLO E NLO QCD+E NLO QCD E LHC 3 TeV µr = µf = 2 Hlep T CT4 QED 0.05% absolute prediction relative correction wrt. LO dσ/dσlo.4.2 NLO QCD p T,l [GeV] LO NLO QCD+E NLO QCD E NLO E large pos. NLO QCD, large neg. NLO E NLO QCD+E and NLO QCD E differ significantly Marek Schönherr NLO QCD+E predictions for 2l2ν production 0/20

11 Diboson production DF relative importance of -induced. channels wrt. NLO QCD E CT4ed (baseline) no PDF.0 LUXed NNPDF3.0ed dσ/dσnlo QCD E PDF CT4 LUX pp e + µ νe νµ none NNPDF3.0 dσ/dσnlo QCD E..0 NLO QCD EVI NLO QCD EVI YFS NLO QCD EVI CSS p T,l [GeV] all PDF agree that -ind. > 0% for p T > 500 GeV very good agreement between CT4ed and LUXed Marek Schönherr NLO QCD+E predictions for 2l2ν production /20

12 Diboson production DF pp e + µ νe νµ reproduction of full result using publically available tools. E VI apprixomation.0 Kallweit et.al. JHEP04(206)02 exact virtual correction appr. integrated real correction PDF YFS soft photon resummation Schönherr, Krauss JHEP2(2008)08 QED corr. to decays NLO QED for / decays resonance aware. QED dipole shower (CSS) Höche et.al. Phys.Rev.D8(200) QED ISR & FSR not resonance aware dσ/dσnlo QCD E dσ/dσnlo QCD E.0 CT4 LUX none NNPDF3.0 NLO QCD EVI NLO QCD EVI YFS NLO QCD EVI CSS p T,l [GeV] both YFS-based and QED-PS approx. reproduce exact result well possibility of practical approximation with current tools Marek Schönherr NLO QCD+E predictions for 2l2ν production 2/20

13 Diboson production DF pp e + µ νe νµ pp e + µ νe νµ dσ/d ET [pb/gev] LO NLO QCD NLO E NLO QCD+E NLO QCD E LHC 3 TeV µr = µf = 2 Hlep T CT4 QED 0.05% dσ/dσnlo QCD E..0 PDF CT4 LUX none NNPDF3.0.6 dσ/dσlo dσ/dσnlo QCD E..0 NLO QCD EVI NLO QCD EVI YFS NLO QCD EVI CSS ET [GeV] ET [GeV] kinematic suppression for pt νν at LO, unlocked at NLO QCD not present in -induced large contrib Marek Schönherr NLO QCD+E predictions for 2l2ν production 3/20

14 Diboson production DF pp e + µ νe νµ pp e + µ νe νµ dσ/dm llνν [pb/gev] LHC 3 TeV µr = µf = 2 Hlep T CT4 QED 0.05% LO NLO QCD NLO E NLO QCD+E NLO QCD E dσ/dσnlo QCD E..0 PDF CT4 LUX none NNPDF3.0 dσ/dσlo dσ/dσnlo QCD E..0 NLO QCD EVI NLO QCD EVI YFS NLO QCD EVI CSS m llνν [GeV] m llνν [GeV] resonance preservation crucial, otherwise δ E off by factor 2 at high p T hard non-resummable radiation dominates Marek Schönherr NLO QCD+E predictions for 2l2ν production 4/20

15 Diboson production SF pp e + e ν ν pp e + e ν ν dσ/dpt [pb/gev] LO NLO QCD NLO E NLO QCD+E NLO QCD E LHC 3 TeV µr = µf = 2 Hlep T CT4 QED 0.05% dσ/dσnlo QCD E..0 PDF CT4 LUX none NNPDF3.0 dσ/dσlo.4.2 dσ/dσnlo QCD E pp [ e + ν] [ e ν] pp [ e + e ] [ ν ν] incoherent sum p T,l [GeV] p T,l [GeV] very similar to DF due to small contrib no interference effects as bosons not forced off-shell Marek Schönherr NLO QCD+E predictions for 2l2ν production 5/20

16 Diboson production SF pp e + e ν ν pp e + e ν ν dσ/dpt [pb/gev] LO NLO QCD NLO E NLO QCD+E NLO QCD E LHC 3 TeV µr = µf = 2 Hlep T CT4 QED 0.05% dσ/dσnlo QCD E..0 PDF CT4 LUX none NNPDF3.0 dσ/dσlo dσ/dσnlo QCD E pp [ e + ν] [ e ν] pp [ e + e ] [ ν ν] incoherent sum p T,l2 [GeV] p T,l2 [GeV] dominant at very large p T different E corrections, take care when extrapolating Marek Schönherr NLO QCD+E predictions for 2l2ν production 6/20

17 Diboson production SF pp e + e ν ν pp e + e ν ν dσ/d ET [pb/gev] LO NLO QCD NLO E NLO QCD+E NLO QCD E LHC 3 TeV µr = µf = 2 Hlep T CT4 QED 0.05% dσ/dσnlo QCD E..0 PDF CT4 LUX none NNPDF3.0 dσ/dσlo dσ/dσnlo QCD E pp [ e + ν] [ e ν] pp [ e + e ] [ ν ν] incoherent sum ET [GeV] ET [GeV] kinematic suppression for pt νν for, but not dominates for MET > 00 GeV with large E corr. Marek Schönherr NLO QCD+E predictions for 2l2ν production 7/20

18 Diboson production DF vs. SF pp e + µ νe νµ pp e + e ν ν dσ/dm ll [pb/gev] LO NLO QCD NLO E NLO QCD+E NLO QCD E LHC 3 TeV µr = µf = 2 Hlep T CT4 QED 0.05% dσ/dm ll [pb/gev] LO NLO QCD NLO E NLO QCD+E NLO QCD E LHC 3 TeV µr = µf = 2 Hlep T CT4 QED 0.05%.2.2 dσ/dσlo dσ/dσlo m ll [GeV] m ll [GeV] dominant at -peak otherwise dominated very similar high-m ll behaviour Marek Schönherr NLO QCD+E predictions for 2l2ν production 8/20

19 Conclusions full automation of NLO QCD and NLO E in SHERPA fixed-order NLO E will become available in SHERPA-2.3 approximate NLO E particle level predictions recovarable through public tools approximate NLO E corrections can be incorporated in NLO QCD multijet merging since SHERPA Marek Schönherr NLO QCD+E predictions for 2l2ν production 9/20

20 Thank you for your attention! Marek Schönherr NLO QCD+E predictions for 2l2ν production 20/20

21 Backup Marek Schönherr NLO QCD+E predictions for 2l2ν production 2/20

22 Acceptance cuts and input parameters E T > 20 GeV p T,l ± > 20 GeV η l ± < 2.5 R l+ > 0.2 H jet T < 0.2 HT l G F = GeV 2 M = GeV Γ = GeV M = GeV Γ = GeV M H = 25 GeV Γ H = 4.07 MeV m b = 4.75 GeV Γ b = 0 m t = 73.2 GeV Γ t =.339 GeV Marek Schönherr NLO QCD+E predictions for 2l2ν production 22/20

23 Diboson production SF pp e + e ν µ/τ ν µ/τ pp e + e ν µ/τ ν µ/τ dσ/dσnlo QCD E..0 PDF CT4 LUX none NNPDF3.0 dσ/dσnlo QCD E..0 PDF CT4 LUX none NNPDF3.0 dσ/dσnlo QCD E..0 NLO QCD EVI YFS NLO QCD EVI CSS dσ/dσnlo QCD E..0 NLO QCD EVI YFS NLO QCD EVI CSS ET [GeV] m llνν [GeV] -only channels very well recovered through YFS and CSS Marek Schönherr NLO QCD+E predictions for 2l2ν production 23/20

24 Diboson production SF pp e + e ν ν pp e + e ν ν dσ/dσnlo QCD E..0 PDF CT4 LUX none NNPDF3.0 dσ/dσnlo QCD E..0 PDF CT4 LUX none NNPDF3.0 dσ/dσnlo QCD E 0.4 pp [ e + ν] [ e ν] pp [ e + e ] [ ν ν] incoherent sum dσ/dσnlo QCD E 0.4 pp [ e + ν] [ e ν] pp [ e + e ] [ ν ν] incoherent sum m ll [GeV] m lν [GeV] and topologies dominant in their resonance region Marek Schönherr NLO QCD+E predictions for 2l2ν production 24/20