flgint.F

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C **********************************************************************

      FUNCTION flgint(Z)

C...Gluon contribution integrand to QCD longitudinal structure function.

*
* to avoid variable conflictions, a second keep element is necessary
* with the same common block name (see LPTOU2)
*
      COMMON /leptou/ cut(14),lst(40),parl(30),
     &                x,y,w2,q2,u
      REAL cut,parl,x,y,w2,q2,u
      INTEGER lst
      SAVE /leptou/

      COMMON /linter/ pari(50),ewqc(2,2,8),qc(8),zl(2,4),zq(2,8),pq(17)
      REAL  pari,ewqc,qc,zl,zq,pq
      SAVE /linter/

      COMMON /linteg/ ntot,npass
      INTEGER ntot,npass
      SAVE /linteg/


      REAL flgint,z,xpq,pi
      dimension xpq(-6:6)
      DATA pi/3.14159/
      ntot=ntot+1
      CALL lnstrf(z,q2,xpq)
      flgint=20./9.*parl(25)/pi*(x/z)**2*(1.-x/z)/z*xpq(0)
      npass=npass+1

      RETURN
      END