subroutine gg_hWWg(p,msq) implicit none C-----Author R.K. Ellis May 2007 c---- matrix element for H production c----in the heavy quark (mt=Infinity) limit. C----averaged over initial colours and spins C----f(p1)+f(p2) --> H(W^+(-->nu(p3)+e^+(p4)) +W^-(-->e^-(p5)+nu~(p6)))+g(p7) include 'constants.f' include 'masses.f' include 'qcdcouple.f' include 'ewcouple.f' integer j,k,iglue double precision msq(-nf:nf,-nf:nf),p(mxpart,4) double precision ss,tt,uu,mhsq,hdecay,s(mxpart,mxpart) double precision s3456,Asq,fac parameter(iglue=7) c--set msq=0 to initialize do j=-nf,nf do k=-nf,nf msq(j,k)=0d0 enddo enddo call dotem(iglue,p,s) s3456=s(3,4)+s(3,5)+s(3,6)+s(4,5)+s(4,6)+s(5,6) hdecay=gwsq**3*wmass**2*s(3,5)*s(6,4) hdecay=hdecay/(((s3456-hmass**2)**2+(hmass*hwidth)**2) . *((s(3,4)-wmass**2)**2+(wmass*wwidth)**2) . *((s(5,6)-wmass**2)**2+(wmass*wwidth)**2)) Asq=(as/(3d0*pi))**2/vevsq fac=Asq*gsq*hdecay c-- calculate propagators ss=s(1,2) tt=s(1,iglue) uu=s(2,iglue) mhsq=ss+tt+uu msq(0,0)= . avegg*fac*V*xn*(mhsq**4+ss**4+tt**4+uu**4)/(ss*tt*uu) msq(1,-1)=+aveqq*fac*V/2d0*(tt**2+uu**2)/ss msq(0,+1)=-aveqg*fac*V/2d0*(ss**2+tt**2)/uu msq(+1,0)=-aveqg*fac*V/2d0*(ss**2+uu**2)/tt do j=-nf,nf do k=-nf,nf if ((k .eq. -j) .and. (j .ne. 0)) then msq(j,k)=msq(1,-1) elseif ((j .eq. 0) .and. (k .ne. 0)) then msq(j,k)=msq(0,1) elseif ((j .ne. 0) .and. (k .eq. 0)) then msq(j,k)=msq(1,0) endif enddo enddo return end