1 #include "isajet/pilot.h"
4 C COMPUTE THE WEINBERG-SALAM HIGGS CROSS SECTION
5 C D(SIGMA)/D(QMW**2)D(YW)D(OMEGA)
6 C FOR THE SPECIFIED JET TYPES. TRIVIAL EXCEPT FOR W W FUSION,
7 C WHICH HAS INTERFERENCE WITH W W SCATTERING.
9 #include "isajet/itapes.inc"
10 #include "isajet/qcdpar.inc"
11 #include "isajet/jetpar.inc"
12 #include "isajet/pjets.inc"
13 #include "isajet/primar.inc"
14 #include "isajet/q1q2.inc"
15 #include "isajet/jetsig.inc"
16 #include "isajet/wsig.inc"
17 #include "isajet/qsave.inc"
18 #include "isajet/wcon.inc"
19 #include "isajet/const.inc"
20 #include "isajet/hcon.inc"
22 DIMENSION X(2),LISTJ(29),WTHELI(4)
23 EQUIVALENCE (S,SHAT),(T,THAT),(U,UHAT),(X(1),X1)
24 #if defined(CERNLIB_DOUBLE)
25 DOUBLE PRECISION C,TERM,SUM,DENOM,ZCM
28 C WTHELI ARE WEIGHTS OF HELICITY AMPLITUDES IN SIGMA.
29 DATA WTHELI/1.,2.,2.,4./
31 $9,1,-1,2,-2,3,-3,4,-4,5,-5,6,-6,
32 $11,-11,12,-12,13,-13,14,-14,15,-15,16,-16,
35 C QUARK OR GLUON FUSION TO HIGGS
37 IF(INITYP(1).LE.25) THEN
42 C W+W FUSION AND W+W->W+W IN EFFECTIVE W APPROXIMATION.
47 IFIN1=LISTJ(INITYP(1))
48 IFIN2=LISTJ(INITYP(2))
51 PINPF=SQRT((S-4.*WMI**2)*(S-4.*WMF**2))
52 ZCM=(.5*S+T-WMI**2-WMF**2)/(.5*PINPF)
53 C RESET COEFFICIENTS FOR SELECTED PROCESS
69 C SUM CROSS SECTION TERMS. I,J RUN OVER AMPLITUDE TERMS.
70 C L RUNS OVER HELICITY STATES. N RUNS OVER POWERS.
71 C REMEMBER THAT L=4 IS MISSING SIN(THETA)/SQRT(2)
75 DENOM=1./((ADWWWW(1,I)+ADWWWW(2,I)*ZCM)
76 $*(ADWWWW(1,J)+ADWWWW(2,J)*ZCM))
84 114 C=C+ANWWWW(K+1,I,L)*ANWWWW(N-K+1,J,L)
89 IF(L.EQ.4) TERM=TERM*(1.-ZCM**2)/2.
94 C ADD IMAGINARY PART SQUARED.
95 SUM=SUM+WTHELI(1)*AIWWWW(1)**2+WTHELI(2)*AIWWWW(2)**2
96 $+WTHELI(3)*AIWWWW(3)**2+WTHELI(4)*AIWWWW(4)**2
97 C CROSS SECTION. NOTE D(OMEGA)=2.*PI*D(Z)
98 SIG0=SUM/(64.*PI**2*S*SCM)*UNITS
99 SIG0=SIG0*TBRWW(JETTYP(1)-25,1)*TBRWW(JETTYP(2)-25,2)
101 IF(IABSF.EQ.90) SIG0=.5*SIG0
102 SIGLLQ=SIG0*QSAVE(INITYP(1),1)*QSAVE(INITYP(2),2)