Multiple electroweak bosons phenomenology at NLO QCD

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1 Multiple electroweak bosons phenomenoloy at NLO QCD Francisco Campanario 15/3/212 I NSTITUTE FOR T HEORETICAL P HYSICS KIT - University of the State of Baden-uerttember and National Research Center of the Helmholtz Association

2 Table of Contents 1 Motivation: VVV and VV(V)j 2 pp ± 3 pp ± j 4 pp VVj 5 Conclusions Francisco Campanario VVV & VV(V)j at NLO 15/3/212 2/14

3 VVV + VVj Production at LHC SM backround for SUSY processes with multi-lepton + p/ T sinature Backround to Hi searches (t th, H) Access to triple and quartic electroweak couplins QCD corrections to pp VVj + X, pp VVV + X on experimentalist s wishlist: [The QCD,E,and His orkin roup: hep-ph/6412] Process (V {Z,,}) Relevant for 1. pp VV+ jet t th, new physics 2. pp t tb b t th 3. pp t t+ 2 jet t th 4. pp VVb b VBF H VV, t th,new physics 5. pp VV+ 2 jets VBF H VV 6. pp V+ 3 jets new physic sinatures 7. pp VVV SUSY trilepton Motivation: VVV and VV(V)j Francisco Campanario VVV & VV(V)j at NLO 15/3/212 3/14

4 Example: pp ± at NLO QCD Backround to new physics (LSP ravitino) and H At LO: q q ± : a) b) c) and couplins Off-shell effects and spin correlations Final state radiation (FSR):l l Final state radiation becomes important: adapt phase space pp ± Francisco Campanario VVV & VV(V)j at NLO 15/3/212 4/14

5 Virtual and Real Corrections..... I II III... I Vertex Corrections propor -tional to Born amplitude II 4-point functions III Up to 5-point functions (Pentaons) Final and initial state luons Soft and collinear sinularities subtracted with Catani-Seymour prescription Frixione isolation criteria Loop Interals: Software in Mathematica.[F.C,arXiv:115.92] pp ± Francisco Campanario VVV & VV(V)j at NLO 15/3/212 5/14

6 Input for LHC phenomenoloy PDFs: CTEQ6L1 at LO and CTE1, α s (m z ) at NLO Input Parameters: m H = 12GeV, M = 8.398GeV, M Z = GeV sinθ =.22264, α 1 = 1/ G F = GeV 2 Cuts: p Tl() > 2(2) GeV y l() < 2.5 R l(j) >.4 R j >.7 pp ± Francisco Campanario VVV & VV(V)j at NLO 15/3/212 6/14

7 ± Production 2 + solid: µ F = µ R = ξ µ dashed: µ F = ξ µ, µ R = µ dotted: µ F = µ, µ R = ξµ Total NLO 15 σ [fb] NLO σ [fb] 1 Real 1 5 Virtual-born LO 5 Virtual-box Virtual-Pentaons ξ ξ K-factor=NLO/LO 3.3! + j at LO dominates overall scale uncertainty K VVV pp ± Francisco Campanario VVV & VV(V)j at NLO 15/3/212 7/14

8 ± Production LO suppressed by Radiation Zero.15 + cosθ> cosθ< cosθ> cosθ< d σ/d y -y + [fb].1 d σ/d y -y + [fb] y -y + y -y + K-factor in central reion around 18 pp ± Francisco Campanario VVV & VV(V)j at NLO 15/3/212 8/14

9 ± Production LO suppressed by Radiation Zero + cosθ> cosθ<.4 + cosθ> cosθ<.15.3 d σ/d y -y + [fb].1 d σ/d y -y + [fb] y -y + y -y + Veto miht help to detect Radiation Zero + j at NLO: Towards NNLO of pp ± Francisco Campanario VVV & VV(V)j at NLO 15/3/212 8/14

10 ± + j Production at LO I) II) III) IV) V) VI) pp ± j Francisco Campanario VVV & VV(V)j at NLO 15/3/212 9/14

11 Virtual corrections for ± + j I) II) III) IV) V) VI) pp ± j Francisco Campanario VVV & VV(V)j at NLO 15/3/212 9/14

12 Virtual corrections for ± + j I) II) III) VII) IV) V) 7 topoloies 7 routines 45 diarams for 28 Details in[f.c,arxiv:115.92], JHEP 111 (211) 7 VI) pp ± j Francisco Campanario VVV & VV(V)j at NLO 15/3/212 9/14

13 ± + j Production µ F = µ R = ξ m 14 NLO 12 Total NLO 12 NLO p T j,cut = 5 GeV 1 Total NLO-p T j,cut σ [fb] 1 8 LO σ [fb] 8 6 Virtual-born 6 4 solid: µ 2 F = µ R = ξ m dashed: µ F = ξ m, µ R = m dotted: µ R = ξ m, µ F = m ξ 4 Real 2 Real-p T j,cut Virtual-hexaons Virtual-box Virtual-pentaons -2 Virtual-fermionbox ξ σ LO [fb] σ NLO [fb] K = σ NLO /σ LO ± +jet (1) (6,.6) 1.48 Tevatron + +jet 4.64(1) 6.528(6,6) 1.4 +jet 3.83(1) 5.544(1,.3) 1.46 LHC ± +jet:24h in 1 Core: σ NLO = 6.5(2,.6) [fb].3% pp ± j Francisco Campanario VVV & VV(V)j at NLO 15/3/212 1/14

14 + + j Production dσ/dmaxp [fb GeV 1 ] LO NLO veto uncertainty NLO (veto) + LHC µ = µ = m maxp [GeV] dσ/dr [fb] LO NLO R K(maxp ) maxp [GeV] K(R) LHC µ = µ = m R Vetoed badly modelled! Additional jet radiation affects LO kinematics pp ± j Francisco Campanario VVV & VV(V)j at NLO 15/3/212 11/14

15 + + j Production dσ/dm [fb GeV 1 ] K(m ) LO NLO veto uncertainty NLO (veto) + LHC µ = µ = m m [GeV] m [GeV] Sizeble corrections If not included: QCD corrections fake anomalous couplins Devoted MC prorams with flexible cut and distributions Expected LARGE NNLO corrections: K j =1.4 (NNLO/NLO) (1.4) NNLO (Leandro Cieri) pp ± j Francisco Campanario VVV & VV(V)j at NLO 15/3/212 12/14

16 NLO QCD j and ± Zj Triple couplins, backrounds to NP, towards NNLO VV. total cross section σ [pb] LO NLO NLO, veto 1 µ/1 GeV Reduce scale uncertainty of total vetoed sample accidental. K-factor=1.4 (NNLO/NLO) VV (1.4). 1 d ū ½º ½º¼ ÔÌ Ñ Ò Ð ¼ ½ ¼ ¼½ ¼ ¼¼½ ÆÄÇ ÄÇ ¼ Î ¼ ¼ ÆÄÇ Òе ÆÄÇ Üе ¼ ¼ ÄÇ ¼ ½¼¼ Ô Ì Ñ Ò Ð Î ν e,z e ½¾¼ µ µ + ÔÔ Ø Ô ½ Ì Î ¼ ½¼¼ ÔÌ Ø ¼ Î ½¾¼ ½ ¼ ½ ¼ pp VVj Francisco Campanario VVV & VV(V)j at NLO 15/3/212 13/14

17 Conclusions NLO QCD corrections are lare: 3 4% for VVj, 4 7% for VVV, for V 3% Scale dependence uncertainty is sinificantly improved Stron phase space dependence Devoted and flexible MonteCarlo proram: VBFNLO VVV : FC,Hankele,Oleari,Prestel,Zeppenfeld,arXiv:89.79, Bozzi,FC,Hankele,Zeppenfeld, arxiv: ,bozzi,fc,rauch,rzehak,zeppenfeld, arxiv: ,g. Bozzi, FC, M. Rauch and D. Zeppenfeld, Phys. Rev. D 83 (211) 11435, Phys. Rev. D 84 (211) 7428 Zj/ j: FC,Enlert,Kallweit,Spannowsky,Zeppenfeld, JHEP 17 (21) 76., FC,Enlert,Spannowsky, Zeppenfeld,Europhys. Lett. 88 (29) 111,FC,Enlert,Spannowsky, Phys. Rev. D82 (21) 5415, Phys. Rev. D 83 (211) 749. j: FC,Enlert,Rauch,Zeppenfeld,arXiv: Conclusions Francisco Campanario VVV & VV(V)j at NLO 15/3/212 14/14

18 +, ZZ and ± Z Production Z, Z, I II III Different infrared diverence structures of individual loop interals but same final virtual expression. Photon isolation from jets for real emission contributions: use Frixione isolation Σ i E Ti θ(δ R i ) p T 1 cosδ 1 cosδ (for all δ δ ) Final state radiation becomes important: adapt phase space Francisco Campanario VVV & VV(V)j at NLO 15/3/212 15/14

19 + Production Variation of µ F,µ R about µ = m 14 solid: µ F = µ R = ξ µ dashed: µ F = ξ µ, µ R = µ dotted: µ F = µ, µ R = ξµ 15 Total NLO 12 1 Virtual-born σ [fb] 1 NLO σ [fb] 5 8 LO Real 6 Virtual-box Virtual-Pentaons ξ ξ LO scale variation smaller that NLO corrections NLO scale uncertainty due to real emission contributions Francisco Campanario VVV & VV(V)j at NLO 15/3/212 16/14

20 + Production µ F = µ R = µ d σ/d p T [fb].3.2 K-factor LO NLO p T p T Stron phase space dependence of K-factor No cte factor can be applied to correct the distributions Devoted MC prorams with flexible cut and distributions VBFNLO at Francisco Campanario VVV & VV(V)j at NLO 15/3/212 17/14

21 For cut-accepted points with VBFNLO for E pp jj Number of Events Raw Imp6 QUAD s Number of Events Raw Imp Imp2 Imp3 Imp4 Imp5 Imp lo1(ε ) lo1(ε ) 1 2 ǫ=abs((quad-dbl))/abs(quad) Imp(,2,3,n): Gaue test 1 ( 1, 2, 3,n) Dble=QUAD Francisco Campanario VVV & VV(V)j at NLO 15/3/212 18/14

22 Timin type boxline penline hexline CPU time 8µ s 7µ s 2 ms Time for Gaue Test 8% 3% 28% n o Gaue Test Total time for Gaue Test 16% 9 % 112 % Failed Gaue test(accuracy 1 6 ).2% 3% Additional time for bad point QUAD precision.4% 12% Reevaluate aue test.2% 4% Total CPU time (See test) 1µ s 14µ s 4.5(2.88) ms Final Instabilities(Accuracy 1 6 ).1 Final Instabilities(Accuracy 1 4 ) Francisco Campanario VVV & VV(V)j at NLO 15/3/212 19/14