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SUBROUTINE SB_SF_008(P,ANS_SUMMED)
C
C Generated by MadGraph5_aMC@NLO v. %(version)s, %(date)s
C By the MadGraph5_aMC@NLO Development Team
C Visit launchpad.net/madgraph5 and amcatnlo.web.cern.ch
C
C
C Return the sum of the split orders which are required in
C orders.inc (BORN_ORDERS)
C Also the values needed for the counterterms are stored in the
C C_BORN_CNT common block
C
C
C Process: g g > t t~ [ real = QED QCD ] QCD^2<=4 QED^2<=2
C spectators: 4 4
C
C
C CONSTANTS
C
IMPLICIT NONE
INCLUDE 'nexternal.inc'
INTEGER NSQAMPSO
PARAMETER (NSQAMPSO=1)
C
C ARGUMENTS
C
REAL*8 P(0:3,NEXTERNAL), ANS_SUMMED
C
C VARIABLES
C
INTEGER I,J
INCLUDE 'orders.inc'
REAL*8 ANS(0:NSQAMPSO)
LOGICAL KEEP_ORDER_CNT(NSPLITORDERS, NSQAMPSO)
COMMON /C_KEEP_ORDER_CNT/ KEEP_ORDER_CNT
INTEGER AMP_ORDERS(NSPLITORDERS)
DOUBLE PRECISION TINY
PARAMETER (TINY = 1D-12)
DOUBLE PRECISION MAX_VAL
C
C FUNCTIONS
C
INTEGER GETORDPOWFROMINDEX_B
INTEGER ORDERS_TO_AMP_SPLIT_POS
C
C BEGIN CODE
C
CALL SB_SF_008_SPLITORDERS(P,ANS)
C color-linked borns are called for QCD-type emissions
ANS_SUMMED = 0D0
MAX_VAL = 0D0
C reset the amp_split_cnt array
AMP_SPLIT_CNT(1:AMP_SPLIT_SIZE,1:2,1:NSPLITORDERS) = DCMPLX(0D0
$ ,0D0)
DO I = 1, NSQAMPSO
MAX_VAL = MAX(MAX_VAL, ABS(ANS(I)))
ENDDO
DO I = 1, NSQAMPSO
IF (KEEP_ORDER_CNT(QCD_POS, I)) THEN
ANS_SUMMED = ANS_SUMMED + ANS(I)
DO J = 1, NSPLITORDERS
AMP_ORDERS(J) = GETORDPOWFROMINDEX_B(J, I)
C take into account the fact that this is for QCD
IF (J.EQ.QCD_POS) AMP_ORDERS(J) = AMP_ORDERS(J) + 2
ENDDO
!amp_split_cnt(orders_to_amp_split_pos(amp_orders),1,qcd_pos) = ans(I)
IF(ABS(ANS(I)).GT.MAX_VAL*TINY)
$ AMP_SPLIT_CNT(ORDERS_TO_AMP_SPLIT_POS(AMP_ORDERS),1
$ ,QCD_POS) = ANS(I)
ENDIF
ENDDO
C this is to avoid fake non-zero contributions
IF (ABS(ANS_SUMMED).LT.MAX_VAL*TINY) ANS_SUMMED=0D0
RETURN
END
SUBROUTINE SB_SF_008_SPLITORDERS(P1,ANS)
C
C Generated by MadGraph5_aMC@NLO v. %(version)s, %(date)s
C By the MadGraph5_aMC@NLO Development Team
C Visit launchpad.net/madgraph5 and amcatnlo.web.cern.ch
C
C RETURNS AMPLITUDE SQUARED SUMMED/AVG OVER COLORS
C AND HELICITIES
C FOR THE POINT IN PHASE SPACE P(0:3,NEXTERNAL-1)
C
C Process: g g > t t~ [ real = QED QCD ] QCD^2<=4 QED^2<=2
C spectators: 4 4
C
IMPLICIT NONE
C
C CONSTANTS
C
INCLUDE 'nexternal.inc'
INTEGER NCOMB
PARAMETER ( NCOMB= 16 )
INTEGER NSQAMPSO
PARAMETER (NSQAMPSO=1)
INTEGER THEL
PARAMETER (THEL=NCOMB*10)
INTEGER NGRAPHS
PARAMETER (NGRAPHS= 3)
C
C ARGUMENTS
C
REAL*8 P1(0:3,NEXTERNAL-1),ANS(0:NSQAMPSO)
C
C LOCAL VARIABLES
C
INTEGER IHEL,IDEN,I,J
DOUBLE PRECISION T(NSQAMPSO)
INTEGER IDEN_VALUES(10)
DATA IDEN_VALUES /256, 256, 256, 256, 256, 256, 256, 256, 256,
$ 256/
C
C GLOBAL VARIABLES
C
LOGICAL GOODHEL(NCOMB,10)
COMMON /C_GOODHEL/ GOODHEL
DOUBLE PRECISION SAVEMOM(NEXTERNAL-1,2)
COMMON/TO_SAVEMOM/SAVEMOM
LOGICAL CALCULATEDBORN
COMMON/CCALCULATEDBORN/CALCULATEDBORN
INTEGER NFKSPROCESS
COMMON/C_NFKSPROCESS/NFKSPROCESS
C ----------
C BEGIN CODE
C ----------
IDEN=IDEN_VALUES(NFKSPROCESS)
IF (CALCULATEDBORN) THEN
DO J=1,NEXTERNAL-1
IF (SAVEMOM(J,1).NE.P1(0,J) .OR. SAVEMOM(J,2).NE.P1(3,J))
$ THEN
CALCULATEDBORN=.FALSE.
WRITE(*,*) 'Error in sb_sf: momenta not the same in the'
$ //' born'
STOP
ENDIF
ENDDO
ELSE
WRITE(*,*) 'Error in sb_sf: color_linked borns should be'
$ //' called only with calculatedborn = true'
STOP
ENDIF
DO I=0,NSQAMPSO
ANS(I) = 0D0
ENDDO
DO IHEL=1,NCOMB
IF (GOODHEL(IHEL,NFKSPROCESS)) THEN
CALL B_SF_008(IHEL,T)
DO I=1,NSQAMPSO
ANS(I)=ANS(I)+T(I)
ENDDO
ENDIF
ENDDO
DO I=1,NSQAMPSO
ANS(I)=ANS(I)/DBLE(IDEN)
ANS(0)=ANS(0)+ANS(I)
ENDDO
END
SUBROUTINE B_SF_008(HELL,ANS)
C
C Generated by MadGraph5_aMC@NLO v. %(version)s, %(date)s
C By the MadGraph5_aMC@NLO Development Team
C Visit launchpad.net/madgraph5 and amcatnlo.web.cern.ch
C RETURNS AMPLITUDE SQUARED SUMMED/AVG OVER COLORS
C FOR THE POINT WITH EXTERNAL LINES W(0:6,NEXTERNAL-1)
C Process: g g > t t~ [ real = QED QCD ] QCD^2<=4 QED^2<=2
C spectators: 4 4
C
IMPLICIT NONE
C
C CONSTANTS
C
INTEGER NAMPSO, NSQAMPSO
PARAMETER (NAMPSO=1, NSQAMPSO=1)
INTEGER NGRAPHS
PARAMETER ( NGRAPHS = 3 )
INTEGER NCOLOR1, NCOLOR2
PARAMETER (NCOLOR1=2, NCOLOR2=2)
REAL*8 ZERO
PARAMETER (ZERO=0D0)
COMPLEX*16 IMAG1
PARAMETER (IMAG1 = (0D0,1D0))
INCLUDE 'nexternal.inc'
INCLUDE 'born_nhel.inc'
C
C ARGUMENTS
C
INTEGER HELL
REAL*8 ANS(NSQAMPSO)
C
C LOCAL VARIABLES
C
INTEGER I,J,M,N
REAL*8 DENOM(NCOLOR1), CF(NCOLOR2,NCOLOR1)
COMPLEX*16 ZTEMP, AMP(NGRAPHS), JAMP1(NCOLOR1,NAMPSO),
$ JAMP2(NCOLOR2,NAMPSO)
C
C GLOBAL VARIABLES
C
DOUBLE COMPLEX SAVEAMP(NGRAPHS,MAX_BHEL)
COMMON/TO_SAVEAMP/SAVEAMP
LOGICAL CALCULATEDBORN
COMMON/CCALCULATEDBORN/CALCULATEDBORN
C
C FUNCTION
C
INTEGER SQSOINDEXB
C
C COLOR DATA
C
DATA DENOM(1)/3/
DATA (CF(I, 1),I= 1, 2) / 16, -2/
DATA DENOM(2)/3/
DATA (CF(I, 2),I= 1, 2) / -2, 16/
C ----------
C BEGIN CODE
C ----------
IF (.NOT. CALCULATEDBORN) THEN
WRITE(*,*) 'Error in b_sf: color_linked borns should be called'
$ //' only with calculatedborn = true'
STOP
ELSEIF (CALCULATEDBORN) THEN
DO I=1,NGRAPHS
AMP(I)=SAVEAMP(I,HELL)
ENDDO
ENDIF
C JAMP1s contributing to orders QCD=2 QED=0
JAMP1(1,1)=+IMAG1*AMP(1)-AMP(2)
JAMP1(2,1)=-IMAG1*AMP(1)-AMP(3)
C JAMP2s contributing to orders QCD=2 QED=0
JAMP2(1,1)=+1D0/4D0*(+3D0*IMAG1*AMP(1)-1D0/3D0*IMAG1*AMP(1)-3D0
$ *AMP(2)+1D0/3D0*AMP(2))
JAMP2(2,1)=+1D0/4D0*(-3D0*IMAG1*AMP(1)+1D0/3D0*IMAG1*AMP(1)-3D0
$ *AMP(3)+1D0/3D0*AMP(3))
DO I = 1, NSQAMPSO
ANS(I) = 0D0
ENDDO
DO M = 1, NAMPSO
DO I = 1, NCOLOR1
ZTEMP = (0.D0,0.D0)
DO J = 1, NCOLOR2
ZTEMP = ZTEMP + CF(J,I)*JAMP2(J,M)
ENDDO
DO N = 1, NAMPSO
ANS(SQSOINDEXB(M,N))=ANS(SQSOINDEXB(M,N))+ZTEMP
$ *DCONJG(JAMP1(I,N))/DENOM(I)
ENDDO
ENDDO
ENDDO
END
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