https://gitlab.cern.ch/POWHEG/POWHEG-BOX-V2

ggZZ NLO (private version, as of 2019-07-06)

Compilation

Latest is on NLO level. You would need CLN, ginac, fastjet and LHAPDF installed with the same compiler. You need to modify part of Makefile to include them.

Note that the gnu version need to be >= 4.9 for some fortran support. Otherwise you would spend too much time compiling gg2vvamp then found the incompatibility and had to upgrade.. Also it's better to use gnu version < 8, since some warning becomes error. You need to change -OPT="-O2 -std=legacy" if you insist to go for gcc8

Running

Useful twiki: https://twiki.cern.ch/twiki/bin/view/Main/PowhegBOX

Some example input file:

http://uaf-10.t2.ucsd.edu/~phchang/analysis/generator/genproductions/bin/Powheg/examples/V1/8TeV_Summer12/ZZ_4e_mll4_8TeV-powheg/v1/ZZ_4e_mll4_8TeV-powheg.input

If LHAPDF Interpolator is not found, you need to add "/cvmfs/.../LHAPDF/share/LHAPDF/" to your env $LHAPDF_DATA_PATH (of course also the pdf sets, too). More in: https://sft.its.cern.ch/jira/browse/SPI-959

LHAPDF set id: https://lhapdf.hepforge.org/pdfsets.html

-- RongkunWang - 2019-07-06