#include "isajet/pilot.h" SUBROUTINE SETH C C Set the standard Weinberg-Salam Higgs parameters in /HCON/. C HMASS = Higgs mass C HGAM = Higgs width C HGAMS = Higgs partial width C ZSTARS = minimum allowed mass for Z* C C IQ = 1 2 3 4 5 6 7 8 9 10 11 12 13 C GL UP UB DN DB ST SB CH CB BT BB TP TB C IQ = 14 15 16 17 18 19 20 21 22 23 24 25 C NUE ANUE E- E+ NUMU ANUM MU- MU+ NUT ANUT TAU- TAU+ C IQ = 26 27 28 29 C GM W+ W- Z0 C C Ver 6.25: Added H -> GM GM. C Ver 6.26: Added H -> Z0 Z* from Keung and Marciano, Phys. C Rev. D30, 248 (1984). C Ver 6.30: Fixed sign of FFR in H -> GM GM for TAU<1. Added C H -> W W* to total width but not to partial widths C to get right branching ratios. C Ver 7.38: Add H_SM decay modes to SSSAVE for use in WHIGGS C #if defined(CERNLIB_IMPNONE) IMPLICIT NONE #endif #include "isajet/itapes.inc" #include "isajet/keys.inc" #include "isajet/wcon.inc" #include "isajet/qlmass.inc" #include "isajet/q1q2.inc" #include "isajet/nodcay.inc" #include "isajet/const.inc" #include "isajet/hcon.inc" C REAL GAMFCN,X,AMASS,AMQ,GAMQ,AML,WM,GAMWW,TAU,FFR,FFI,FR,FI, $ROOT,ROOTLN,TM,SUMBR,TERM,ETAR,ETAI,RQ,RQLOG,PHIR,PHII REAL EPS,FEPS,AM12 INTEGER IQ,IQ1,IQ2,I,IW INTEGER LISTJ(25),LISTW(4) DATA LISTJ/ $9,1,-1,2,-2,3,-3,4,-4,5,-5,6,-6, $11,-11,12,-12,13,-13,14,-14,15,-15,16,-16/ DATA LISTW/10,80,-80,90/ C GAMFCN(X)=SQRT(1.-4*X**2)*(1.-4.*X**2+12.*X**4) C C Calculate Higgs mass and width C HMASS=AMASS(81) HGAM=0. DO 100 IQ=1,29 100 HGAMS(IQ)=0. C C Quarks and leptons DO 110 IQ=1,6 AMQ=AMASS(IQ) IF(AMQ.GT.0..AND.AMQ.LT..5*HMASS) THEN GAMQ=3.*GF*AMQ**2*HMASS/(4.*PI*SQRT2) $ *(SQRT(1.-4.*AMQ**2/HMASS**2))**3 HGAM=HGAM+GAMQ HGAMS(2*IQ)=.5*GAMQ HGAMS(2*IQ+1)=.5*GAMQ CALL SSSAVE(81,GAMQ,IQ,-IQ,0,0,0) ENDIF AML=AMASS(IQ+10) IF(AML.GT.0..AND.AML.LT..5*HMASS) THEN GAMQ=GF*AML**2*HMASS/(4.*PI*SQRT2) $ *(SQRT(1.-4.*AML**2/HMASS**2))**3 HGAM=HGAM+GAMQ HGAMS(2*IQ+12)=.5*GAMQ HGAMS(2*IQ+13)=.5*GAMQ CALL SSSAVE(81,GAMQ,IQ+10,-(IQ+10),0,0,0) ENDIF 110 CONTINUE C C W+ W- and Z0 Z0, including W W* and Z Z*. WM=WMASS(2) IF(HMASS.GT.2.*WM) THEN GAMWW=GF*HMASS**3*GAMFCN(WM/HMASS)/(8.*PI*SQRT2) HGAM=HGAM+GAMWW HGAMS(27)=.5*GAMWW HGAMS(28)=.5*GAMWW CALL SSSAVE(81,GAMWW,80,-80,0,0,0) ELSEIF(HMASS.GT.WM) THEN EPS=WM/HMASS FEPS=3.*(1.-8.*EPS**2+20.*EPS**4)/SQRT(4.*EPS**2-1.) $ *ACOS((3.*EPS**2-1.)/(2.*EPS**3)) $ -(1.-EPS**2)*(47./2.*EPS**2-13./2.+1./EPS**2) $ -3.*(1.-6.*EPS**2+4.*EPS**4)*ALOG(EPS) GAMWW=3.*ALFA**2*HMASS/(32.*PI*SIN2W**2)*FEPS HGAM=HGAM+GAMWW HGAMS(27)=.5*GAMWW HGAMS(28)=.5*GAMWW CALL SSSAVE(81,GAMWW/18.,80,12,-11,0,0) CALL SSSAVE(81,GAMWW/18.,-80,-12,11,0,0) CALL SSSAVE(81,GAMWW/18.,80,14,-13,0,0) CALL SSSAVE(81,GAMWW/18.,-80,-14,13,0,0) CALL SSSAVE(81,GAMWW/18.,80,16,-15,0,0) CALL SSSAVE(81,GAMWW/18.,-80,-16,15,0,0) CALL SSSAVE(81,GAMWW/6.,80,-1,2,0,0) CALL SSSAVE(81,GAMWW/6.,-80,1,-2,0,0) CALL SSSAVE(81,GAMWW/6.,80,-4,3,0,0) CALL SSSAVE(81,GAMWW/6.,-80,4,-3,0,0) ENDIF WM=WMASS(4) IF(HMASS.GT.2.*WM) THEN GAMWW=GF*HMASS**3*GAMFCN(WM/HMASS)/(16.*PI*SQRT2) HGAM=HGAM+GAMWW HGAMS(29)=GAMWW CALL SSSAVE(81,GAMWW,90,90,0,0,0) ELSEIF(HMASS.GT.WM) THEN EPS=WM/HMASS FEPS=3.*(1.-8.*EPS**2+20.*EPS**4)/SQRT(4.*EPS**2-1.) $ *ACOS((3.*EPS**2-1.)/(2.*EPS**3)) $ -(1.-EPS**2)*(47./2.*EPS**2-13./2.+1./EPS**2) $ -3.*(1.-6.*EPS**2+4.*EPS**4)*ALOG(EPS) GAMWW=ALFA**2*HMASS/(128.*PI*SIN2W**2*(1.-SIN2W)**2) $ *(7.-40./3.*SIN2W+160./9.*SIN2W**2)*FEPS HGAM=HGAM+GAMWW HGAMS(29)=GAMWW CALL SSSAVE(81,.11922*GAMWW,90,-1,1,0,0) CALL SSSAVE(81,.15375*GAMWW,90,-2,2,0,0) CALL SSSAVE(81,.15375*GAMWW,90,-3,3,0,0) CALL SSSAVE(81,.11922*GAMWW,90,-4,4,0,0) CALL SSSAVE(81,.15375*GAMWW,90,-5,5,0,0) CALL SSSAVE(81,.06668*GAMWW,90,-11,11,0,0) CALL SSSAVE(81,.03343*GAMWW,90,-12,12,0,0) CALL SSSAVE(81,.06668*GAMWW,90,-13,13,0,0) CALL SSSAVE(81,.03343*GAMWW,90,-14,14,0,0) CALL SSSAVE(81,.06668*GAMWW,90,-15,15,0,0) CALL SSSAVE(81,.03343*GAMWW,90,-16,16,0,0) ENDIF C W* and Z* mass limits DO 120 I=1,2 ZSTARS(1,I)=0. DO 130 IW=2,4 ZSTARS(IW,I)=AMASS(LISTW(IW)) DO 140 IQ1=2,25 IQ2=MATCH(IQ1,IW) IF(IQ2.EQ.0) GO TO 140 IF(GOWW(IQ1,1).AND.GOWW(IQ2,2)) THEN AM12=AMASS(LISTJ(IQ1))+AMASS(LISTJ(IQ2)) ZSTARS(IW,I)=MIN(ZSTARS(IW,I),AM12) ENDIF 140 CONTINUE 130 CONTINUE 120 CONTINUE C C GM GM -- W loop term WM=WMASS(2) TAU=4.*WM**2/HMASS**2 IF(TAU.GE.1.0) THEN FFR=(ASIN(1./SQRT(TAU)))**2 FFI=0. ELSE ROOT=SQRT(1.-TAU) ROOTLN=ALOG((1.+ROOT)/(1.-ROOT)) FFR=-0.25*(ROOTLN**2-PI**2) FFI=0.5*PI*ROOTLN ENDIF FR=2.+3.*TAU+3.*TAU*(2.-TAU)*FFR FI=3.*TAU*(2.-TAU)*FFI C Top loop term TM=AMASS(6) TAU=4.*TM**2/HMASS**2 IF(TAU.GE.1.0) THEN FFR=(ASIN(1./SQRT(TAU)))**2 FFI=0. ELSE ROOT=SQRT(1.-TAU) ROOTLN=ALOG((1.+ROOT)/(1.-ROOT)) FFR=-0.25*(ROOTLN**2-PI**2) FFI=0.5*PI*ROOTLN ENDIF FR=FR-8./3.*TAU*(1.+(1.-TAU)*FFR) FI=FI-8./3.*TAU*(1.-TAU)*FFI C Total GM GM HGAMS(26)=ALFA**3/(256.*PI**2*SIN2W)*HMASS**3/WM**2*(FR**2+FI**2) HGAM=HGAM+HGAMS(26) CALL SSSAVE(81,HGAMS(26),10,10,0,0,0) C C Calculate Higgs-gluon-gluon coupling C ETAR=0. ETAI=0. DO 300 IQ=1,8 AMQ=AMASS(IQ) IF(AMQ.LE.0.) GO TO 300 RQ=(2.*AMQ/HMASS)**2 IF(RQ.GE.1.) THEN ETAR=ETAR+.5*RQ*(1.+(1.-RQ)*ASIN(1./SQRT(RQ))**2) ELSE RQLOG=ALOG((1.+SQRT(1.-RQ))/(1.-SQRT(1.-RQ))) PHIR=.25*(RQLOG**2-PI**2) ETAR=ETAR+.5*RQ*(1.+(RQ-1.)*PHIR) PHII=.5*PI*RQLOG ETAI=ETAI+.5*RQ*(1.+(RQ-1.)*PHII) ENDIF 300 CONTINUE ETAHGG=ETAR**2+ETAI**2 C RETURN END