flqint.F

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

      FUNCTION flqint(Z)

C...Quark 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/


      INTEGER i
      REAL xpq,z,flqint,pi
      dimension xpq(-6:6)
      DATA pi/3.14159/
      ntot=ntot+1
      CALL lnstrf(z,q2,xpq)
      flqint=0.
      DO 100 i=-lst(12),lst(12)
      IF(i.EQ.0) goto 100
      flqint=flqint+qc(iabs(i))**2*xpq(i)
  100 CONTINUE
      flqint=4./3.*parl(25)/pi*(x/z)**2*flqint/z
      npass=npass+1

      RETURN
      END