polnlo.F

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C*********************************************************************
      
      SUBROUTINE polnlo(IFLAG,X,Q2,
     &                  dxduv,dxddv,dxdg,dxdubar,dxddbar,dxds)
      IMPLICIT NONE      
      DOUBLE PRECISION aux(6),xd,q2d
      DOUBLE PRECISION dxduv,dxddv,dxdg,dxdubar,dxddbar,dxds      
      INTEGER iflag
      REAL x,q2


c ---- NLO polarized parton distributions as described in
c ---- T. Gehrmann and W.J. Stirling:
c ---- Polarized Parton Distributions of the Nucleon
c ---- Durham preprint DTP/95/82
c ----
c ---- DXDUV = u-ubar
c ---- DXDDV = d-dbar 
c ---- DXDG  = gluon
c ---- DXDUBAR = 1/2 usea
c ---- DXDDBAR = 1/2 dsea
c ---- DXDS = sbar = 1/2 strsea

      xd=dble(x)
      q2d=dble(q2)

      call rdarrynlo(xd,q2d,aux,iflag)
      dxduv=aux(1)*(xd**0.6d0*(1.d0-xd)**3)
      dxddv=aux(2)*(xd**0.75d0*(1.d0-xd)**4)
      dxdg=aux(3)*(xd**0.5d0*(1.d0-xd)**5)
      dxdubar=aux(4)*(xd**0.5d0*(1.d0-xd)**6)
      dxddbar=aux(5)*(xd**0.5d0*(1.d0-xd)**6)
      dxds=aux(6)*(xd**0.5d0*(1.d0-xd)**6)
      
      return
      end