*     -*-fortran-*-

c Common blocks for NLO or aMC@NLO reweighting
c Conventions for array relevant to NLO computations:
c   i=1,2,3,4  -> event, soft, collinear, soft-collinear
c   ==>  i = icountevts+2 for counterevents

c The following is introduced since this file may be included in codes
c that need not know nexternal. Make sure that maxparticles>=nexternal
      integer maxparticles,maxFKSconfigs
      parameter (maxparticles=20,maxFKSconfigs=120)

c Reference weight and Ellis-Sexton scales
      double precision wgtref,wgtqes2(4)
      common/cwgt0/wgtref,wgtqes2

c Reference weights for parton level NLO (event, counterevent, Born)
      double precision wgtrefNLO11,wgtrefNLO12,wgtrefNLO20
      common/cwgt0NLO/wgtrefNLO11,wgtrefNLO12,wgtrefNLO20

c Bjorken x's
      double precision wgtxbj(2,4)
      common/cwgt1/wgtxbj

c Kinematic configurations
      double precision wgtkinE(0:3,maxparticles,4)
      common/cwgt2E/wgtkinE

c Reference renormalization and factorization scales squared
      double precision wgtmuR2(4),wgtmuF12(4),wgtmuF22(4)
      common/cwgt2mu/wgtmuR2,wgtmuF12,wgtmuF22

c Real-emission weights, scale independent
      double precision wgtwreal(4)
      common/cwgt3/wgtwreal

c (n+1)-body degenerate weights, scale independent
      double precision wgtwdeg(4)
      common/cwgt4/wgtwdeg

c (n+1)-body degenerate weights, muF dependence
      double precision wgtwdegmuf(4)
      common/cwgt5/wgtwdegmuf

c n-body weights: Born, n-body NLO scale independent,
c   n-body NLO scale muF dependence, n-body NLO scale muR dependence
      double precision wgtwborn(2:2),wgtwns(2:2),
     #                 wgtwnsmuf(2:2),wgtwnsmur(2:2)
      common/cwgt6/wgtwborn,wgtwns,wgtwnsmuf,wgtwnsmur

c MC stuff: MC counterterms proper, and Bjorken x's
      double precision wgtwmcxsecE(maxparticles),
     #                 wgtmcxbjE(2,maxparticles)
      common/cwgt7E/wgtwmcxsecE,wgtmcxbjE

c MC stuff: number of father's colour partners
      integer iwgtnumpartn
      common/cwgt8/iwgtnumpartn

c Auxiliary quantities used when writing events
      integer jwgtinfo,mexternal
      common/cwgtaux0/jwgtinfo,mexternal

c
c Cross sections after variations of scales and PDFs
c
      integer maxscales,maxPDFs
      parameter (maxscales=9)
      parameter (maxPDFs=200)

c New format to allow for multiple PDF sets and scales (both functional form
c and normal)
      integer    maxPDFsets,   maxdynscales
      parameter (maxPDFsets=25,maxdynscales=10)
      integer lhaPDFid(0:maxPDFsets),nmemPDF(maxPDFsets)
     $     ,dyn_scale(0:maxdynscales)
      logical lscalevar(maxdynscales),lpdfvar(maxPDFsets)
      character*100 LHAPDFsetname(maxPDFsets)
      double precision scalevarR(0:maxscales),scalevarF(0:maxscales)
      common/new_format_scale_pdf/LHAPDFsetname,scalevarR,scalevarF
     $     ,lhaPDFid,nmemPDF,dyn_scale,lscalevar,lpdfvar

c Number of scale factors (for each scale) and PDF error pairs
      integer numscales,numPDFpairs,numPDFs
      common/cwgxsec1/numscales,numPDFpairs,numPDFs

c Cross sections at different scales and PDFs
      double precision wgtxsecmu(maxscales,maxscales,maxdynscales),
     #                 wgtxsecPDF(0:maxPDFs,maxPDFsets)
      common/cwgxsec2/wgtxsecmu,wgtxsecPDF

c Cross sections at different scales and PDFs, for NLO computations
c The first entry is relevant to event (1), counterevents (2), and Born (3),
c and corresponds to iplot=11, 12, and 20 respectively
      double precision wgtNLOxsecmu(3,maxscales,maxscales),
     #                 wgtNLOxsecPDF(3,0:maxPDFs)
      common/cwgxsec3/wgtNLOxsecmu,wgtNLOxsecPDF

c Power of alpha_s in the Born (only used if jwgtinfo.eq.4)
      double precision wgtbpower
      common/cwgtbpower/wgtbpower

c This variable is only used in reweight_xsec.f and only if jwgtinfo.ne.4
c If jwgtinfo.eq.4 the value in the common block is used
      double precision rwgtbpower
      parameter (rwgtbpower=3.d0)

c nFKSprocess used for the nbody and the .not.nbody
      integer nFKSprocess_used,nFKSprocess_used_Born
      common /c_nFKSproc_file/ nFKSprocess_used,nFKSprocess_used_Born

c cpower: power of muR-dependent factor in the born
      double precision wgtcpower
      common/cwgtcpower/wgtcpower

c input of cpower (checked against calculated value)
      double precision cpowerinput
      parameter (cpowerinput=0.d0)

c switch for running muR-dependent factor runfac=1(running)/0(fixed)
      integer runfac
      parameter (runfac=0)
c WARNING: If you set runfac=1 to include a muR-dependent factor
c          make sure you modified the function rwgt_muR_dep_fac in
c	   reweight_xsec.f and compute_cpower in fks_singular.f
c          appropiately to include all muR dependent overall factors
c          (except for alpha_s) in the calculation. This procedure 
c          will be incorrect, if you miss one of the muR dependent
c          factors or if there is a not factorizing muR dependent term.
c	   You also have to set ren_group_coeff_in and cpowerinput
c	   to the proper values.

c first order coefficient of renormalization group equation of the
c muR-dependent factor,
c e.g. for masses:      ren_group_coeff = gamma0 = 3/2*C_F,
c i.e. also for Yukawa: ren_group_coeff = gamma0
      double precision ren_group_coeff_in
      parameter (ren_group_coeff_in=0d0)

c NLO+NNLL jet veto stuff
      double precision veto_multiplier,H1_factor_virt,
     &                 veto_compensating_factor,born_wgt_veto
      common/cwgt_jet_veto/veto_multiplier,H1_factor_virt,
     &                     veto_compensating_factor,born_wgt_veto

      integer n_ctr_found,max_n_ctr,n_mom_conf
      parameter (max_n_ctr=256)
      character*1024 n_ctr_str(max_n_ctr)
      double precision momenta_str(0:3,maxparticles,max_n_ctr)
      common /c_rwgt_lines/n_ctr_str,momenta_str,n_ctr_found,n_mom_conf

      integer max_weight_shower
      parameter (max_weight_shower=1024)