VH calculations of the LHC HXSWG for the yellow report number 4

Standard Model parameters

See document at https://cds.cern.ch/record/2047636/files/LHCHXSWG-INT-2015-006.pdf

Phase space requirements/classification

For Higgs decaying into b-quarks, the following phase space cuts need to be applied to the daughers b-jets:

• b-jets: |η| <2.5, p_T > 25 GeV

If the Higgs boson is not decayed, then the b-jet cuts are to be ignored.

Z(ll)H(bb)

• Z p_T bins: inclusive, [0-100 GeV], (100 GeV-200 GeV], >200 GeV
• leptons: |η| <2.5, p_T > 15 GeV
• m_ll in range [75-105 GeV]

Z(νν)H(bb)

• Z p_T bins: inclusive, [0-150 GeV], (150 GeV-250 GeV], >250 GeV

W(lν)H(bb)

• W p_T bins: inclusive, [0-150 GeV], (150 GeV-250 GeV], >250 GeV
• leptons: |η|<2.5, p_T > 15 GeV
• neutrinos: p_T > 15 GeV

Additional jet counting

• Additional jets count if p_T > 20 GeV and |η| < 4.5

This jet counting helps define the exclusive VH+0-jet and VH+1-jet regions.

Proposed plots (histograms) for Yellow Report 4

100 bins each

• 0 < pT_H < 500 (a)
• -5 < y_H < 5 (b)
• 0 < pT_lepton < 500 (c)
• 0 < pT_nu/nubar < 500 (d)
• -5 < y_lepton < 5 (e)

For the other 5 plots above (a-e) we are going to produce 4 sets of plots:

• one set inclusive over pT_W/Z and
• one set for each of the 3 pT_W/Z bins reported on the wiki page.

The plot below (1) can be produced for the inclusive case only

• 0 < pT_W/Z < 500 (1)

Differential cross sections from HAWK (NLO QCD and NLO EW):

• histograms for EW corrections & photon-induced in text format: VH-NLO-distributions.tar.gz
  • column 1: kinematical quantity on x-axis (x = left corner of bin)
  • column 2: Monte Carlo average for the Born cross-section
  • column 3: Monte Carlo error for the Born cross-section
  • column 4: Monte Carlo average for the complete cross-section
  • column 5: Monte Carlo error for the complete cross-section
  • column 6: Monte Carlo average for virt+real ew cross-section
  • column 7: Monte Carlo error for virt+real ew cross-section
  • column 8: Monte Carlo average for virt+real QCD cross-section
  • column 9: Monte Carlo error for virt+real QCD cross-section
  • column 10: Monte Carlo average for incoming photon cross-section
  • column 11: Monte Carlo error for incoming photon cross-section
  • column 12: Monte Carlo average for incoming gluon cross-section
  • column 13: Monte Carlo error for incoming gluon cross-section

• histograms for EW corrections & photon-induced in ROOT format: EWK_corrections_VH.root

Differential cross sections from VHNNLO (NNLO QCD):

• histograms for QCD corrections in text format: QCDdist.tgz
• histograms for QCD corrections & photon-induced in ROOT format: QCD_corrections_VH.root

How to combine the NLO EWK and NNLO QCD corrections (work in progress)

The "deltaEW" can be built making the bin by bin ratio between column 6 and column 2 (nloEW/bornEW). The Born terms don't fully coincide exactly because of PDF. The idea is to multply the NNLO QCD-DY like prediction for the deltaEW factor (the EW correction factorizes exactly up to NLO) and to this one can sum column 10 as it is plus the non-DY-like (ggZH) contribution.

Rivet Analysis

https://github.com/perrozzi/rivet_analysis_VH_YR4

-- JasonNielsen - 2015-11-30