3 C***********************************************************************
5 SUBROUTINE PYSIGH_HIJING(NCHN,SIGS)
7 C...Differential matrix elements for all included subprocesses.
8 C...Note that what is coded is (disregarding the COMFAC factor)
9 C...1) for 2 -> 1 processes: s-hat/pi*d(sigma-hat), where,
10 C...when d(sigma-hat) is given in the zero-width limit, the delta
11 C...function in tau is replaced by a Breit-Wigner:
12 C...1/pi*(s*m_res*Gamma_res)/((s*tau-m_res^2)^2+(m_res*Gamma_res)^2);
13 C...2) for 2 -> 2 processes: (s-hat)**2/pi*d(sigma-hat)/d(t-hat);
14 C...i.e., dimensionless quantities. COMFAC contains the factor
15 C...pi/s and the conversion factor from GeV^-2 to mb.
16 #include "ludat1_hijing.inc"
17 #include "ludat2_hijing.inc"
18 #include "ludat3_hijing.inc"
19 #include "pysubs_hijing.inc"
20 #include "pypars_hijing.inc"
21 #include "pyint1_hijing.inc"
22 #include "pyint2_hijing.inc"
23 #include "pyint3_hijing.inc"
24 #include "pyint4_hijing.inc"
25 #include "pyint5_hijing.inc"
26 DIMENSION X(2),XPQ(-6:6),KFAC(2,-40:40),WDTP(0:40),WDTE(0:40,0:5)
28 C...Reset number of channels and cross-section.
32 C...Read kinematical variables and limits.
52 C...Derive kinematical quantities.
53 IF(ISET(ISUB).LE.2.OR.ISET(ISUB).EQ.5) THEN
54 X(1)=SQRT(TAU)*EXP(YST)
55 X(2)=SQRT(TAU)*EXP(-YST)
57 X(1)=SQRT(TAUP)*EXP(YST)
58 X(2)=SQRT(TAUP)*EXP(-YST)
60 IF(MINT(43).EQ.4.AND.ISET(ISUB).GE.1.AND.
61 &(X(1).GT.0.999.OR.X(2).GT.0.999)) RETURN
67 BE34=SQRT((1.-RM3-RM4)**2-4.*RM3*RM4)
68 RPTS=4.*VINT(71)**2/SH
69 BE34L=SQRT(MAX(0.,(1.-RM3-RM4)**2-4.*RM3*RM4-RPTS))
72 RTHM=(4.*RM3*RM4+RPTS)/(1.-RM3-RM4+BE34L)
73 TH=-0.5*SH*MAX(RTHM,1.-RM3-RM4-BE34*CTH)
74 UH=-0.5*SH*MAX(RTHM,1.-RM3-RM4+BE34*CTH)
75 SQPTH=0.25*SH*BE34**2*(1.-CTH**2)
80 C...Choice of Q2 scale.
81 IF(ISET(ISUB).EQ.1.OR.ISET(ISUB).EQ.3) THEN
83 ELSEIF(MOD(ISET(ISUB),2).EQ.0.OR.ISET(ISUB).EQ.5) THEN
84 IF(MSTP(32).EQ.1) THEN
85 Q2=2.*SH*TH*UH/(SH**2+TH**2+UH**2)
86 ELSEIF(MSTP(32).EQ.2) THEN
87 Q2=SQPTH+0.5*(SQM3+SQM4)
88 ELSEIF(MSTP(32).EQ.3) THEN
90 ELSEIF(MSTP(32).EQ.4) THEN
93 IF(ISET(ISUB).EQ.5.AND.MSTP(82).GE.2) Q2=Q2+PARP(82)**2
96 C...Store derived kinematical quantities.
105 VINT(50)=TAUP*VINT(2)
106 VINT(49)=SQRT(MAX(0.,VINT(50)))
110 C...Calculate parton structure functions.
111 IF(ISET(ISUB).LE.0) GOTO 145
112 IF(MINT(43).GE.2) THEN
114 IF(ISET(ISUB).EQ.3.OR.ISET(ISUB).EQ.4) THEN
116 IF(ISUB.EQ.8.OR.ISUB.EQ.76.OR.ISUB.EQ.77) Q2SF=PMAS(24,1)**2
118 DO 100 I=3-MINT(41),MINT(42)
120 IF(ISET(ISUB).EQ.5) XSF=X(I)/VINT(142+I)
121 CALL PYSTFU_HIJING(MINT(10+I),XSF,Q2SF,XPQ,I)
123 100 XSFX(I,KFL)=XPQ(KFL)
126 C...Calculate alpha_strong and K-factor.
127 IF(MSTP(33).NE.3) AS=ULALPS_HIJING(Q2)
130 IF(MSTP(33).EQ.1) THEN
132 ELSEIF(MSTP(33).EQ.2) THEN
134 FACA=PARP(32)/PARP(31)
135 ELSEIF(MSTP(33).EQ.3) THEN
137 IF(ISET(ISUB).EQ.5.AND.MSTP(82).GE.2) Q2AS=Q2AS+
139 AS=ULALPS_HIJING(Q2AS)
143 C...Set flags for allowed reacting partons/leptons.
147 IF(MINT(40+I).EQ.1) THEN
152 IF(ABS(J).GT.MSTP(54).AND.J.NE.21) KFAC(I,J)=0
154 IF(XSFX(I,J).LT.1.E-10) KFAC(I,J)=0
156 IF(XSFX(I,0).LT.1.E-10) KFAC(I,21)=0
162 C...Lower and upper limit for flavour loops.
168 IF(KFAC(1,-J).EQ.1) MIN1=-J
169 IF(KFAC(1,J).EQ.1) MAX1=J
170 IF(KFAC(2,-J).EQ.1) MIN2=-J
171 IF(KFAC(2,J).EQ.1) MAX2=J
176 C...Common conversion factors (including Jacobian) for subprocesses.
178 GMMZ=PMAS(23,1)*PMAS(23,2)
180 GMMW=PMAS(24,1)*PMAS(24,2)
182 GMMH=PMAS(25,1)*PMAS(25,2)
184 GMMZP=PMAS(32,1)*PMAS(32,2)
186 GMMHC=PMAS(37,1)*PMAS(37,2)
188 GMMR=PMAS(40,1)*PMAS(40,2)
192 C...Phase space integral in tau and y*.
193 COMFAC=PARU(1)*PARU(5)/VINT(2)
194 IF(MINT(43).EQ.4) COMFAC=COMFAC*FACK
195 IF((MINT(43).GE.2.OR.ISET(ISUB).EQ.3.OR.ISET(ISUB).EQ.4).AND.
196 &ISET(ISUB).NE.5) THEN
197 ATAU0=LOG(TAUMAX/TAUMIN)
198 ATAU1=(TAUMAX-TAUMIN)/(TAUMAX*TAUMIN)
199 H1=COEF(ISUB,1)+(ATAU0/ATAU1)*COEF(ISUB,2)/TAU
200 IF(MINT(72).GE.1) THEN
203 ATAU2=LOG(TAUMAX/TAUMIN*(TAUMIN+TAUR1)/(TAUMAX+TAUR1))/TAUR1
204 ATAU3=(ATAN((TAUMAX-TAUR1)/GAMR1)-ATAN((TAUMIN-TAUR1)/GAMR1))/
206 H1=H1+(ATAU0/ATAU2)*COEF(ISUB,3)/(TAU+TAUR1)+
207 & (ATAU0/ATAU3)*COEF(ISUB,4)*TAU/((TAU-TAUR1)**2+GAMR1**2)
209 IF(MINT(72).EQ.2) THEN
212 ATAU4=LOG(TAUMAX/TAUMIN*(TAUMIN+TAUR2)/(TAUMAX+TAUR2))/TAUR2
213 ATAU5=(ATAN((TAUMAX-TAUR2)/GAMR2)-ATAN((TAUMIN-TAUR2)/GAMR2))/
215 H1=H1+(ATAU0/ATAU4)*COEF(ISUB,5)/(TAU+TAUR2)+
216 & (ATAU0/ATAU5)*COEF(ISUB,6)*TAU/((TAU-TAUR2)**2+GAMR2**2)
218 COMFAC=COMFAC*ATAU0/(TAU*H1)
220 IF(MINT(43).EQ.4.AND.ISET(ISUB).NE.5) THEN
222 AYST1=0.5*(YSTMAX-YSTMIN)**2
224 AYST3=2.*(ATAN(EXP(YSTMAX))-ATAN(EXP(YSTMIN)))
225 H2=(AYST0/AYST1)*COEF(ISUB,7)*(YST-YSTMIN)+(AYST0/AYST2)*
226 & COEF(ISUB,8)*(YSTMAX-YST)+(AYST0/AYST3)*COEF(ISUB,9)/COSH(YST)
227 COMFAC=COMFAC*AYST0/H2
230 C...2 -> 1 processes: reduction in angular part of phase space integral
231 C...for case of decaying resonance.
232 ACTH0=CTNMAX-CTNMIN+CTPMAX-CTPMIN
233 IF((ISET(ISUB).EQ.1.OR.ISET(ISUB).EQ.3).AND.
234 &MDCY(KFPR(ISUB,1),1).EQ.1) THEN
235 IF(KFPR(ISUB,1).EQ.25.OR.KFPR(ISUB,1).EQ.37) THEN
236 COMFAC=COMFAC*0.5*ACTH0
238 COMFAC=COMFAC*0.125*(3.*ACTH0+CTNMAX**3-CTNMIN**3+
239 & CTPMAX**3-CTPMIN**3)
242 C...2 -> 2 processes: angular part of phase space integral.
243 ELSEIF(ISET(ISUB).EQ.2.OR.ISET(ISUB).EQ.4) THEN
244 ACTH1=LOG((MAX(RM34,RSQM-CTNMIN)*MAX(RM34,RSQM-CTPMIN))/
245 & (MAX(RM34,RSQM-CTNMAX)*MAX(RM34,RSQM-CTPMAX)))
246 ACTH2=LOG((MAX(RM34,RSQM+CTNMAX)*MAX(RM34,RSQM+CTPMAX))/
247 & (MAX(RM34,RSQM+CTNMIN)*MAX(RM34,RSQM+CTPMIN)))
248 ACTH3=1./MAX(RM34,RSQM-CTNMAX)-1./MAX(RM34,RSQM-CTNMIN)+
249 & 1./MAX(RM34,RSQM-CTPMAX)-1./MAX(RM34,RSQM-CTPMIN)
250 ACTH4=1./MAX(RM34,RSQM+CTNMIN)-1./MAX(RM34,RSQM+CTNMAX)+
251 & 1./MAX(RM34,RSQM+CTPMIN)-1./MAX(RM34,RSQM+CTPMAX)
253 & (ACTH0/ACTH1)*COEF(ISUB,11)/MAX(RM34,RSQM-CTH)+
254 & (ACTH0/ACTH2)*COEF(ISUB,12)/MAX(RM34,RSQM+CTH)+
255 & (ACTH0/ACTH3)*COEF(ISUB,13)/MAX(RM34,RSQM-CTH)**2+
256 & (ACTH0/ACTH4)*COEF(ISUB,14)/MAX(RM34,RSQM+CTH)**2
257 COMFAC=COMFAC*ACTH0*0.5*BE34/H3
260 C...2 -> 3, 4 processes: phace space integral in tau'.
261 IF(MINT(43).GE.2.AND.(ISET(ISUB).EQ.3.OR.ISET(ISUB).EQ.4)) THEN
262 ATAUP0=LOG(TAUPMX/TAUPMN)
263 ATAUP1=((1.-TAU/TAUPMX)**4-(1.-TAU/TAUPMN)**4)/(4.*TAU)
265 & ATAUP0/ATAUP1*COEF(ISUB,16)/TAUP*(1.-TAU/TAUP)**3
266 IF(1.-TAU/TAUP.GT.1.E-4) THEN
267 FZW=(1.+TAU/TAUP)*LOG(TAUP/TAU)-2.*(1.-TAU/TAUP)
269 FZW=1./6.*(1.-TAU/TAUP)**3*TAU/TAUP
271 COMFAC=COMFAC*ATAUP0*FZW/H4
274 C...Phase space integral for low-pT and multiple interactions.
275 IF(ISET(ISUB).EQ.5) THEN
276 COMFAC=PARU(1)*PARU(5)*FACK*0.5*VINT(2)/SH2
277 ATAU0=LOG(2.*(1.+SQRT(1.-XT2))/XT2-1.)
278 ATAU1=2.*ATAN(1./XT2-1.)/SQRT(XT2)
279 H1=COEF(ISUB,1)+(ATAU0/ATAU1)*COEF(ISUB,2)/SQRT(TAU)
280 COMFAC=COMFAC*ATAU0/H1
282 AYST1=0.5*(YSTMAX-YSTMIN)**2
283 AYST3=2.*(ATAN(EXP(YSTMAX))-ATAN(EXP(YSTMIN)))
284 H2=(AYST0/AYST1)*COEF(ISUB,7)*(YST-YSTMIN)+(AYST0/AYST1)*
285 & COEF(ISUB,8)*(YSTMAX-YST)+(AYST0/AYST3)*COEF(ISUB,9)/COSH(YST)
286 COMFAC=COMFAC*AYST0/H2
287 IF(MSTP(82).LE.1) COMFAC=COMFAC*XT2**2*(1./VINT(149)-1.)
288 C...For MSTP(82)>=2 an additional factor (xT2/(xT2+VINT(149))**2 is
289 C...introduced to make cross-section finite for xT2 -> 0.
290 IF(MSTP(82).GE.2) COMFAC=COMFAC*XT2**2/(VINT(149)*
294 C...A: 2 -> 1, tree diagrams.
296 145 IF(ISUB.LE.10) THEN
298 C...f + fb -> gamma*/Z0.
300 CALL PYWIDT_HIJING(23,SQRT(SH),WDTP,WDTE)
301 FACZ=COMFAC*AEM**2*4./3.
303 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 150
304 EI=KCHG(IABS(I),1)/3.
308 IF(IABS(I).LE.10) FACF=FACA/3.
313 SIGH(NCHN)=FACF*FACZ*(EI**2*VINT(111)+EI*VI/(8.*XW*(1.-XW))*
314 & SH*(SH-SQMZ)/((SH-SQMZ)**2+GMMZ**2)*VINT(112)+(VI**2+AI**2)/
315 & (16.*XW*(1.-XW))**2*SH2/((SH-SQMZ)**2+GMMZ**2)*VINT(114))
318 ELSEIF(ISUB.EQ.2) THEN
320 CALL PYWIDT_HIJING(24,SQRT(SH),WDTP,WDTE)
321 FACW=COMFAC*(AEM/XW)**2*1./24*SH2/((SH-SQMW)**2+GMMW**2)
323 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 170
326 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 160
328 IF(I*J.GT.0.OR.MOD(IA+JA,2).EQ.0) GOTO 160
329 IF((IA.LE.10.AND.JA.GT.10).OR.(IA.GT.10.AND.JA.LE.10)) GOTO 160
330 KCHW=(KCHG(IA,1)*ISIGN(1,I)+KCHG(JA,1)*ISIGN(1,J))/3
332 IF(IA.LE.10) FACF=VCKM((IA+1)/2,(JA+1)/2)*FACA/3.
337 SIGH(NCHN)=FACF*FACW*(WDTE(0,1)+WDTE(0,(5-KCHW)/2)+WDTE(0,4))
341 ELSEIF(ISUB.EQ.3) THEN
343 CALL PYWIDT_HIJING(25,SQRT(SH),WDTP,WDTE)
344 FACH=COMFAC*(AEM/XW)**2*1./48.*(SH/SQMW)**2*
345 & SH2/((SH-SQMH)**2+GMMH**2)*(WDTE(0,1)+WDTE(0,2)+WDTE(0,4))
347 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 180
348 RMQ=PMAS(IABS(I),1)**2/SH
353 SIGH(NCHN)=FACH*RMQ*SQRT(MAX(0.,1.-4.*RMQ))
356 ELSEIF(ISUB.EQ.4) THEN
357 C...gamma + W+/- -> W+/-.
359 ELSEIF(ISUB.EQ.5) THEN
361 CALL PYWIDT_HIJING(25,SQRT(SH),WDTP,WDTE)
362 FACH=COMFAC*1./(128.*PARU(1)**2*16.*(1.-XW)**3)*(AEM/XW)**4*
363 & (SH/SQMW)**2*SH2/((SH-SQMH)**2+GMMH**2)*
364 & (WDTE(0,1)+WDTE(0,2)+WDTE(0,4))
366 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 200
368 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 190
369 EI=KCHG(IABS(I),1)/3.
372 EJ=KCHG(IABS(J),1)/3.
379 SIGH(NCHN)=FACH*(VI**2+AI**2)*(VJ**2+AJ**2)
383 ELSEIF(ISUB.EQ.6) THEN
384 C...Z0 + W+/- -> W+/-.
386 ELSEIF(ISUB.EQ.7) THEN
389 ELSEIF(ISUB.EQ.8) THEN
391 CALL PYWIDT_HIJING(25,SQRT(SH),WDTP,WDTE)
392 FACH=COMFAC*1./(128*PARU(1)**2)*(AEM/XW)**4*(SH/SQMW)**2*
393 & SH2/((SH-SQMH)**2+GMMH**2)*(WDTE(0,1)+WDTE(0,2)+WDTE(0,4))
395 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 220
396 EI=SIGN(1.,FLOAT(I))*KCHG(IABS(I),1)
398 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 210
399 EJ=SIGN(1.,FLOAT(J))*KCHG(IABS(J),1)
400 IF(EI*EJ.GT.0.) GOTO 210
405 SIGH(NCHN)=FACH*VINT(180+I)*VINT(180+J)
410 C...B: 2 -> 2, tree diagrams.
412 ELSEIF(ISUB.LE.20) THEN
414 C...f + f' -> f + f'.
415 FACQQ1=COMFAC*AS**2*4./9.*(SH2+UH2)/TH2
416 FACQQB=COMFAC*AS**2*4./9.*((SH2+UH2)/TH2*FACA-
417 & MSTP(34)*2./3.*UH2/(SH*TH))
418 FACQQ2=COMFAC*AS**2*4./9.*((SH2+TH2)/UH2-
419 & MSTP(34)*2./3.*SH2/(TH*UH))
421 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 240
423 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 230
429 IF(I.EQ.-J) SIGH(NCHN)=FACQQB
431 SIGH(NCHN)=0.5*SIGH(NCHN)
436 SIGH(NCHN)=0.5*FACQQ2
441 ELSEIF(ISUB.EQ.12) THEN
442 C...f + fb -> f' + fb' (q + qb -> q' + qb' only).
443 CALL PYWIDT_HIJING(21,SQRT(SH),WDTP,WDTE)
444 FACQQB=COMFAC*AS**2*4./9.*(TH2+UH2)/SH2*(WDTE(0,1)+WDTE(0,2)+
445 & WDTE(0,3)+WDTE(0,4))
447 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 250
455 ELSEIF(ISUB.EQ.13) THEN
456 C...f + fb -> g + g (q + qb -> g + g only).
457 FACGG1=COMFAC*AS**2*32./27.*(UH/TH-(2.+MSTP(34)*1./4.)*UH2/SH2)
458 FACGG2=COMFAC*AS**2*32./27.*(TH/UH-(2.+MSTP(34)*1./4.)*TH2/SH2)
460 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 260
465 SIGH(NCHN)=0.5*FACGG1
470 SIGH(NCHN)=0.5*FACGG2
473 ELSEIF(ISUB.EQ.14) THEN
474 C...f + fb -> g + gamma (q + qb -> g + gamma only).
475 FACGG=COMFAC*AS*AEM*8./9.*(TH2+UH2)/(TH*UH)
477 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 270
478 EI=KCHG(IABS(I),1)/3.
483 SIGH(NCHN)=FACGG*EI**2
486 ELSEIF(ISUB.EQ.15) THEN
487 C...f + fb -> g + Z0 (q + qb -> g + Z0 only).
488 FACZG=COMFAC*AS*AEM/(XW*(1.-XW))*1./18.*
489 & (TH2+UH2+2.*SQM4*SH)/(TH*UH)
490 FACZG=FACZG*WIDS(23,2)
492 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 280
493 EI=KCHG(IABS(I),1)/3.
500 SIGH(NCHN)=FACZG*(VI**2+AI**2)
503 ELSEIF(ISUB.EQ.16) THEN
504 C...f + fb' -> g + W+/- (q + qb' -> g + W+/- only).
505 FACWG=COMFAC*AS*AEM/XW*2./9.*(TH2+UH2+2.*SQM4*SH)/(TH*UH)
507 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 300
510 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 290
512 IF(I*J.GT.0.OR.MOD(IA+JA,2).EQ.0) GOTO 290
513 KCHW=(KCHG(IA,1)*ISIGN(1,I)+KCHG(JA,1)*ISIGN(1,J))/3
515 IF(MINT(43).EQ.4) FCKM=VCKM((IA+1)/2,(JA+1)/2)
520 SIGH(NCHN)=FACWG*FCKM*WIDS(24,(5-KCHW)/2)
524 ELSEIF(ISUB.EQ.17) THEN
525 C...f + fb -> g + H0 (q + qb -> g + H0 only).
527 ELSEIF(ISUB.EQ.18) THEN
528 C...f + fb -> gamma + gamma.
529 FACGG=COMFAC*FACA*AEM**2*1./3.*(TH2+UH2)/(TH*UH)
531 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 310
532 EI=KCHG(IABS(I),1)/3.
537 SIGH(NCHN)=FACGG*EI**4
540 ELSEIF(ISUB.EQ.19) THEN
541 C...f + fb -> gamma + Z0.
542 FACGZ=COMFAC*FACA*AEM**2/(XW*(1.-XW))*1./24.*
543 & (TH2+UH2+2.*SQM4*SH)/(TH*UH)
544 FACGZ=FACGZ*WIDS(23,2)
546 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 320
547 EI=KCHG(IABS(I),1)/3.
554 SIGH(NCHN)=FACGZ*EI**2*(VI**2+AI**2)
557 ELSEIF(ISUB.EQ.20) THEN
558 C...f + fb' -> gamma + W+/-.
559 FACGW=COMFAC*FACA*AEM**2/XW*1./6.*
560 & ((2.*UH-TH)/(3.*(SH-SQM4)))**2*(TH2+UH2+2.*SQM4*SH)/(TH*UH)
562 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 340
565 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 330
567 IF(I*J.GT.0.OR.MOD(IA+JA,2).EQ.0) GOTO 330
568 KCHW=(KCHG(IA,1)*ISIGN(1,I)+KCHG(JA,1)*ISIGN(1,J))/3
570 IF(MINT(43).EQ.4) FCKM=VCKM((IA+1)/2,(JA+1)/2)
575 SIGH(NCHN)=FACGW*FCKM*WIDS(24,(5-KCHW)/2)
580 ELSEIF(ISUB.LE.30) THEN
582 C...f + fb -> gamma + H0.
584 ELSEIF(ISUB.EQ.22) THEN
585 C...f + fb -> Z0 + Z0.
586 FACZZ=COMFAC*FACA*(AEM/(XW*(1.-XW)))**2*1./768.*
587 & (UH/TH+TH/UH+2.*(SQM3+SQM4)*SH/(TH*UH)-
588 & SQM3*SQM4*(1./TH2+1./UH2))
589 FACZZ=FACZZ*WIDS(23,1)
591 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 350
592 EI=KCHG(IABS(I),1)/3.
599 SIGH(NCHN)=FACZZ*(VI**4+6.*VI**2*AI**2+AI**4)
602 ELSEIF(ISUB.EQ.23) THEN
603 C...f + fb' -> Z0 + W+/-.
604 FACZW=COMFAC*FACA*(AEM/XW)**2*1./6.
605 FACZW=FACZW*WIDS(23,2)
606 THUH=MAX(TH*UH-SQM3*SQM4,SH*CKIN(3)**2)
608 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 370
611 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 360
613 IF(I*J.GT.0.OR.MOD(IA+JA,2).EQ.0) GOTO 360
614 KCHW=(KCHG(IA,1)*ISIGN(1,I)+KCHG(JA,1)*ISIGN(1,J))/3
630 IF(MINT(43).EQ.4) FCKM=VCKM((IA+1)/2,(JA+1)/2)
635 SIGH(NCHN)=FACZW*FCKM*(1./(SH-SQMW)**2*
636 & ((9.-8.*XW)/4.*THUH+(8.*XW-6.)/4.*SH*(SQM3+SQM4))+
637 & (THUH-SH*(SQM3+SQM4))/(2.*(SH-SQMW))*((VJ+AJ)/TH-(VI+AI)/UH)+
638 & THUH/(16.*(1.-XW))*((VJ+AJ)**2/TH2+(VI+AI)**2/UH2)+
639 & SH*(SQM3+SQM4)/(8.*(1.-XW))*(VI+AI)*(VJ+AJ)/(TH*UH))*
640 & WIDS(24,(5-KCHW)/2)
644 ELSEIF(ISUB.EQ.24) THEN
645 C...f + fb -> Z0 + H0.
646 THUH=MAX(TH*UH-SQM3*SQM4,SH*CKIN(3)**2)
647 FACHZ=COMFAC*FACA*(AEM/(XW*(1.-XW)))**2*1./96.*
648 & (THUH+2.*SH*SQMZ)/(SH-SQMZ)**2
649 FACHZ=FACHZ*WIDS(23,2)*WIDS(25,2)
651 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 380
652 EI=KCHG(IABS(I),1)/3.
659 SIGH(NCHN)=FACHZ*(VI**2+AI**2)
662 ELSEIF(ISUB.EQ.25) THEN
663 C...f + fb -> W+ + W-.
664 FACWW=COMFAC*FACA*(AEM/XW)**2*1./12.
665 FACWW=FACWW*WIDS(24,1)
666 THUH=MAX(TH*UH-SQM3*SQM4,SH*CKIN(3)**2)
668 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 390
669 EI=KCHG(IABS(I),1)/3.
672 DSIGWW=THUH/SH2*(3.-(SH-3.*(SQM3+SQM4))/(SH-SQMZ)*
673 & (VI+AI)/(2.*AI*(1.-XW))+(SH/(SH-SQMZ))**2*
674 & (1.-2.*(SQM3+SQM4)/SH+12.*SQM3*SQM4/SH2)*(VI**2+AI**2)/
675 & (8.*(1.-XW)**2))-2.*SQMZ/(SH-SQMZ)*(VI+AI)/AI+
676 & SQMZ*SH/(SH-SQMZ)**2*(1.-2.*(SQM3+SQM4)/SH)*(VI**2+AI**2)/
678 IF(KCHG(IABS(I),1).LT.0) THEN
679 DSIGWW=DSIGWW+2.*(1.+SQMZ/(SH-SQMZ)*(VI+AI)/(2.*AI))*
680 & (THUH/(SH*TH)-(SQM3+SQM4)/TH)+THUH/TH2
682 DSIGWW=DSIGWW+2.*(1.+SQMZ/(SH-SQMZ)*(VI+AI)/(2.*AI))*
683 & (THUH/(SH*UH)-(SQM3+SQM4)/UH)+THUH/UH2
689 SIGH(NCHN)=FACWW*DSIGWW
692 ELSEIF(ISUB.EQ.26) THEN
693 C...f + fb' -> W+/- + H0.
694 THUH=MAX(TH*UH-SQM3*SQM4,SH*CKIN(3)**2)
695 FACHW=COMFAC*FACA*(AEM/XW)**2*1./24.*(THUH+2.*SH*SQMW)/
697 FACHW=FACHW*WIDS(25,2)
699 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 410
702 IF(J.EQ.0.OR.KFAC(1,J).EQ.0) GOTO 400
704 IF(I*J.GT.0.OR.MOD(IA+JA,2).EQ.0) GOTO 400
705 KCHW=(KCHG(IA,1)*ISIGN(1,I)+KCHG(JA,1)*ISIGN(1,J))/3
707 IF(MINT(43).EQ.4) FCKM=VCKM((IA+1)/2,(JA+1)/2)
712 SIGH(NCHN)=FACHW*FCKM*WIDS(24,(5-KCHW)/2)
716 ELSEIF(ISUB.EQ.27) THEN
717 C...f + fb -> H0 + H0.
719 ELSEIF(ISUB.EQ.28) THEN
720 C...f + g -> f + g (q + g -> q + g only).
721 FACQG1=COMFAC*AS**2*4./9.*((2.+MSTP(34)*1./4.)*UH2/TH2-UH/SH)*
723 FACQG2=COMFAC*AS**2*4./9.*((2.+MSTP(34)*1./4.)*SH2/TH2-SH/UH)
727 IF(ISDE.EQ.1.AND.KFAC(1,I)*KFAC(2,21).EQ.0) GOTO 420
728 IF(ISDE.EQ.2.AND.KFAC(1,21)*KFAC(2,I).EQ.0) GOTO 420
742 ELSEIF(ISUB.EQ.29) THEN
743 C...f + g -> f + gamma (q + g -> q + gamma only).
744 FGQ=COMFAC*FACA*AS*AEM*1./3.*(SH2+UH2)/(-SH*UH)
747 EI=KCHG(IABS(I),1)/3.
750 IF(ISDE.EQ.1.AND.KFAC(1,I)*KFAC(2,21).EQ.0) GOTO 440
751 IF(ISDE.EQ.2.AND.KFAC(1,21)*KFAC(2,I).EQ.0) GOTO 440
760 ELSEIF(ISUB.EQ.30) THEN
761 C...f + g -> f + Z0 (q + g -> q + Z0 only).
762 FZQ=COMFAC*FACA*AS*AEM/(XW*(1.-XW))*1./48.*
763 & (SH2+UH2+2.*SQM4*TH)/(-SH*UH)
767 EI=KCHG(IABS(I),1)/3.
770 FACZQ=FZQ*(VI**2+AI**2)
772 IF(ISDE.EQ.1.AND.KFAC(1,I)*KFAC(2,21).EQ.0) GOTO 460
773 IF(ISDE.EQ.2.AND.KFAC(1,21)*KFAC(2,I).EQ.0) GOTO 460
783 ELSEIF(ISUB.LE.40) THEN
785 C...f + g -> f' + W+/- (q + g -> q' + W+/- only).
786 FACWQ=COMFAC*FACA*AS*AEM/XW*1./12.*
787 & (SH2+UH2+2.*SQM4*TH)/(-SH*UH)
791 KCHW=ISIGN(1,KCHG(IA,1)*ISIGN(1,I))
793 IF(ISDE.EQ.1.AND.KFAC(1,I)*KFAC(2,21).EQ.0) GOTO 480
794 IF(ISDE.EQ.2.AND.KFAC(1,21)*KFAC(2,I).EQ.0) GOTO 480
799 SIGH(NCHN)=FACWQ*VINT(180+I)*WIDS(24,(5-KCHW)/2)
803 ELSEIF(ISUB.EQ.32) THEN
804 C...f + g -> f + H0 (q + g -> q + H0 only).
806 ELSEIF(ISUB.EQ.33) THEN
807 C...f + gamma -> f + g (q + gamma -> q + g only).
809 ELSEIF(ISUB.EQ.34) THEN
810 C...f + gamma -> f + gamma.
812 ELSEIF(ISUB.EQ.35) THEN
813 C...f + gamma -> f + Z0.
815 ELSEIF(ISUB.EQ.36) THEN
816 C...f + gamma -> f' + W+/-.
818 ELSEIF(ISUB.EQ.37) THEN
819 C...f + gamma -> f + H0.
821 ELSEIF(ISUB.EQ.38) THEN
822 C...f + Z0 -> f + g (q + Z0 -> q + g only).
824 ELSEIF(ISUB.EQ.39) THEN
825 C...f + Z0 -> f + gamma.
827 ELSEIF(ISUB.EQ.40) THEN
828 C...f + Z0 -> f + Z0.
831 ELSEIF(ISUB.LE.50) THEN
833 C...f + Z0 -> f' + W+/-.
835 ELSEIF(ISUB.EQ.42) THEN
836 C...f + Z0 -> f + H0.
838 ELSEIF(ISUB.EQ.43) THEN
839 C...f + W+/- -> f' + g (q + W+/- -> q' + g only).
841 ELSEIF(ISUB.EQ.44) THEN
842 C...f + W+/- -> f' + gamma.
844 ELSEIF(ISUB.EQ.45) THEN
845 C...f + W+/- -> f' + Z0.
847 ELSEIF(ISUB.EQ.46) THEN
848 C...f + W+/- -> f' + W+/-.
850 ELSEIF(ISUB.EQ.47) THEN
851 C...f + W+/- -> f' + H0.
853 ELSEIF(ISUB.EQ.48) THEN
854 C...f + H0 -> f + g (q + H0 -> q + g only).
856 ELSEIF(ISUB.EQ.49) THEN
857 C...f + H0 -> f + gamma.
859 ELSEIF(ISUB.EQ.50) THEN
860 C...f + H0 -> f + Z0.
863 ELSEIF(ISUB.LE.60) THEN
865 C...f + H0 -> f' + W+/-.
867 ELSEIF(ISUB.EQ.52) THEN
868 C...f + H0 -> f + H0.
870 ELSEIF(ISUB.EQ.53) THEN
871 C...g + g -> f + fb (g + g -> q + qb only).
872 CALL PYWIDT_HIJING(21,SQRT(SH),WDTP,WDTE)
873 FACQQ1=COMFAC*AS**2*1./6.*(UH/TH-(2.+MSTP(34)*1./4.)*UH2/SH2)*
874 & (WDTE(0,1)+WDTE(0,2)+WDTE(0,3)+WDTE(0,4))*FACA
875 FACQQ2=COMFAC*AS**2*1./6.*(TH/UH-(2.+MSTP(34)*1./4.)*TH2/SH2)*
876 & (WDTE(0,1)+WDTE(0,2)+WDTE(0,3)+WDTE(0,4))*FACA
877 IF(KFAC(1,21)*KFAC(2,21).EQ.0) GOTO 500
890 ELSEIF(ISUB.EQ.54) THEN
891 C...g + gamma -> f + fb (g + gamma -> q + qb only).
893 ELSEIF(ISUB.EQ.55) THEN
894 C...g + gamma -> f + fb (g + gamma -> q + qb only).
896 ELSEIF(ISUB.EQ.56) THEN
897 C...g + gamma -> f + fb (g + gamma -> q + qb only).
899 ELSEIF(ISUB.EQ.57) THEN
900 C...g + gamma -> f + fb (g + gamma -> q + qb only).
902 ELSEIF(ISUB.EQ.58) THEN
903 C...gamma + gamma -> f + fb.
905 ELSEIF(ISUB.EQ.59) THEN
906 C...gamma + Z0 -> f + fb.
908 ELSEIF(ISUB.EQ.60) THEN
909 C...gamma + W+/- -> f + fb'.
912 ELSEIF(ISUB.LE.70) THEN
914 C...gamma + H0 -> f + fb.
916 ELSEIF(ISUB.EQ.62) THEN
917 C...Z0 + Z0 -> f + fb.
919 ELSEIF(ISUB.EQ.63) THEN
920 C...Z0 + W+/- -> f + fb'.
922 ELSEIF(ISUB.EQ.64) THEN
923 C...Z0 + H0 -> f + fb.
925 ELSEIF(ISUB.EQ.65) THEN
926 C...W+ + W- -> f + fb.
928 ELSEIF(ISUB.EQ.66) THEN
929 C...W+/- + H0 -> f + fb'.
931 ELSEIF(ISUB.EQ.67) THEN
932 C...H0 + H0 -> f + fb.
934 ELSEIF(ISUB.EQ.68) THEN
936 FACGG1=COMFAC*AS**2*9./4.*(SH2/TH2+2.*SH/TH+3.+2.*TH/SH+
938 FACGG2=COMFAC*AS**2*9./4.*(UH2/SH2+2.*UH/SH+3.+2.*SH/UH+
940 FACGG3=COMFAC*AS**2*9./4.*(TH2/UH2+2.*TH/UH+3+2.*UH/TH+UH2/TH2)
941 IF(KFAC(1,21)*KFAC(2,21).EQ.0) GOTO 510
946 SIGH(NCHN)=0.5*FACGG1
951 SIGH(NCHN)=0.5*FACGG2
956 SIGH(NCHN)=0.5*FACGG3
959 ELSEIF(ISUB.EQ.69) THEN
960 C...gamma + gamma -> W+ + W-.
962 ELSEIF(ISUB.EQ.70) THEN
963 C...gamma + W+/- -> gamma + W+/-.
966 ELSEIF(ISUB.LE.80) THEN
968 C...Z0 + Z0 -> Z0 + Z0.
970 TH=-0.5*SH*BE2*(1.-CTH)
971 UH=-0.5*SH*BE2*(1.+CTH)
972 SHANG=1./(1.-XW)*SQMW/SQMZ*(1.+BE2)**2
973 ASHRE=(SH-SQMH)/((SH-SQMH)**2+GMMH**2)*SHANG
974 ASHIM=-GMMH/((SH-SQMH)**2+GMMH**2)*SHANG
975 THANG=1./(1.-XW)*SQMW/SQMZ*(BE2-CTH)**2
976 ATHRE=(TH-SQMH)/((TH-SQMH)**2+GMMH**2)*THANG
977 ATHIM=-GMMH/((TH-SQMH)**2+GMMH**2)*THANG
978 UHANG=1./(1.-XW)*SQMW/SQMZ*(BE2+CTH)**2
979 AUHRE=(UH-SQMH)/((UH-SQMH)**2+GMMH**2)*UHANG
980 AUHIM=-GMMH/((UH-SQMH)**2+GMMH**2)*UHANG
981 FACH=0.5*COMFAC*1./(4096.*PARU(1)**2*16.*(1.-XW)**2)*
982 & (AEM/XW)**4*(SH/SQMW)**2*((ASHRE+ATHRE+AUHRE)**2+
983 & (ASHIM+ATHIM+AUHIM)**2)*SQMZ/SQMW
985 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 530
986 EI=KCHG(IABS(I),1)/3.
991 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 520
992 EJ=KCHG(IABS(J),1)/3.
1000 SIGH(NCHN)=FACH*AVI*AVJ
1004 ELSEIF(ISUB.EQ.72) THEN
1005 C...Z0 + Z0 -> W+ + W-.
1006 BE2=SQRT((1.-4.*SQMW/SH)*(1.-4.*SQMZ/SH))
1008 TH=-0.5*SH*(1.-2.*(SQMW+SQMZ)/SH-BE2*CTH)
1009 UH=-0.5*SH*(1.-2.*(SQMW+SQMZ)/SH+BE2*CTH)
1010 SHANG=4.*SQRT(SQMW/(SQMZ*(1.-XW)))*(1.-2.*SQMW/SH)*
1012 ASHRE=(SH-SQMH)/((SH-SQMH)**2+GMMH**2)*SHANG
1013 ASHIM=-GMMH/((SH-SQMH)**2+GMMH**2)*SHANG
1014 ATWRE=(1.-XW)/SQMZ*SH/(TH-SQMW)*((CTH-BE2)**2*(3./2.+BE2/2.*CTH-
1015 & (SQMW+SQMZ)/SH+(SQMW-SQMZ)**2/(SH*SQMW))+4.*((SQMW+SQMZ)/SH*
1016 & (1.-3.*CTH2)+8.*SQMW*SQMZ/SH2*(2.*CTH2-1.)+
1017 & 4.*(SQMW**2+SQMZ**2)/SH2*CTH2+2.*(SQMW+SQMZ)/SH*BE2*CTH))
1019 AUWRE=(1.-XW)/SQMZ*SH/(UH-SQMW)*((CTH+BE2)**2*(3./2.-BE2/2.*CTH-
1020 & (SQMW+SQMZ)/SH+(SQMW-SQMZ)**2/(SH*SQMW))+4.*((SQMW+SQMZ)/SH*
1021 & (1.-3.*CTH2)+8.*SQMW*SQMZ/SH2*(2.*CTH2-1.)+
1022 & 4.*(SQMW**2+SQMZ**2)/SH2*CTH2-2.*(SQMW+SQMZ)/SH*BE2*CTH))
1024 A4RE=2.*(1.-XW)/SQMZ*(3.-CTH2-4.*(SQMW+SQMZ)/SH)
1026 FACH=COMFAC*1./(4096.*PARU(1)**2*16.*(1.-XW)**2)*(AEM/XW)**4*
1027 & (SH/SQMW)**2*((ASHRE+ATWRE+AUWRE+A4RE)**2+
1028 & (ASHIM+ATWIM+AUWIM+A4IM)**2)*SQMZ/SQMW
1030 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 550
1031 EI=KCHG(IABS(I),1)/3.
1036 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 540
1037 EJ=KCHG(IABS(J),1)/3.
1045 SIGH(NCHN)=FACH*AVI*AVJ
1049 ELSEIF(ISUB.EQ.73) THEN
1050 C...Z0 + W+/- -> Z0 + W+/-.
1051 BE2=1.-2.*(SQMZ+SQMW)/SH+((SQMZ-SQMW)/SH)**2
1052 EP1=1.+(SQMZ-SQMW)/SH
1053 EP2=1.-(SQMZ-SQMW)/SH
1054 TH=-0.5*SH*BE2*(1.-CTH)
1055 UH=(SQMZ-SQMW)**2/SH-0.5*SH*BE2*(1.+CTH)
1056 THANG=SQRT(SQMW/(SQMZ*(1.-XW)))*(BE2-EP1*CTH)*(BE2-EP2*CTH)
1057 ATHRE=(TH-SQMH)/((TH-SQMH)**2+GMMH**2)*THANG
1058 ATHIM=-GMMH/((TH-SQMH)**2+GMMH**2)*THANG
1059 ASWRE=(1.-XW)/SQMZ*SH/(SH-SQMW)*(-BE2*(EP1+EP2)**4*CTH+
1060 & 1./4.*(BE2+EP1*EP2)**2*((EP1-EP2)**2-4.*BE2*CTH)+
1061 & 2.*BE2*(BE2+EP1*EP2)*(EP1+EP2)**2*CTH-
1062 & 1./16.*SH/SQMW*(EP1**2-EP2**2)**2*(BE2+EP1*EP2)**2)
1064 AUWRE=(1.-XW)/SQMZ*SH/(UH-SQMW)*(-BE2*(EP2+EP1*CTH)*
1065 & (EP1+EP2*CTH)*(BE2+EP1*EP2)+BE2*(EP2+EP1*CTH)*
1066 & (BE2+EP1*EP2*CTH)*(2.*EP2-EP2*CTH+EP1)-BE2*(EP2+EP1*CTH)**2*
1067 & (BE2-EP2**2*CTH)-1./8.*(BE2+EP1*EP2*CTH)**2*((EP1+EP2)**2+
1068 & 2.*BE2*(1.-CTH))+1./32.*SH/SQMW*(BE2+EP1*EP2*CTH)**2*
1069 & (EP1**2-EP2**2)**2-BE2*(EP1+EP2*CTH)*(EP2+EP1*CTH)*
1070 & (BE2+EP1*EP2)+BE2*(EP1+EP2*CTH)*(BE2+EP1*EP2*CTH)*
1071 & (2.*EP1-EP1*CTH+EP2)-BE2*(EP1+EP2*CTH)**2*(BE2-EP1**2*CTH)-
1072 & 1./8.*(BE2+EP1*EP2*CTH)**2*((EP1+EP2)**2+2.*BE2*(1.-CTH))+
1073 & 1./32.*SH/SQMW*(BE2+EP1*EP2*CTH)**2*(EP1**2-EP2**2)**2)
1075 A4RE=(1.-XW)/SQMZ*(EP1**2*EP2**2*(CTH**2-1.)-
1076 & 2.*BE2*(EP1**2+EP2**2+EP1*EP2)*CTH-2.*BE2*EP1*EP2)
1078 FACH=COMFAC*1./(4096.*PARU(1)**2*4.*(1.-XW))*(AEM/XW)**4*
1079 & (SH/SQMW)**2*((ATHRE+ASWRE+AUWRE+A4RE)**2+
1080 & (ATHIM+ASWIM+AUWIM+A4IM)**2)*SQRT(SQMZ/SQMW)
1082 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 570
1083 EI=KCHG(IABS(I),1)/3.
1088 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 560
1089 EJ=KCHG(IABS(J),1)/3.
1097 SIGH(NCHN)=FACH*(AVI*VINT(180+J)+VINT(180+I)*AVJ)
1101 ELSEIF(ISUB.EQ.75) THEN
1102 C...W+ + W- -> gamma + gamma.
1104 ELSEIF(ISUB.EQ.76) THEN
1105 C...W+ + W- -> Z0 + Z0.
1106 BE2=SQRT((1.-4.*SQMW/SH)*(1.-4.*SQMZ/SH))
1108 TH=-0.5*SH*(1.-2.*(SQMW+SQMZ)/SH-BE2*CTH)
1109 UH=-0.5*SH*(1.-2.*(SQMW+SQMZ)/SH+BE2*CTH)
1110 SHANG=4.*SQRT(SQMW/(SQMZ*(1.-XW)))*(1.-2.*SQMW/SH)*
1112 ASHRE=(SH-SQMH)/((SH-SQMH)**2+GMMH**2)*SHANG
1113 ASHIM=-GMMH/((SH-SQMH)**2+GMMH**2)*SHANG
1114 ATWRE=(1.-XW)/SQMZ*SH/(TH-SQMW)*((CTH-BE2)**2*(3./2.+BE2/2.*CTH-
1115 & (SQMW+SQMZ)/SH+(SQMW-SQMZ)**2/(SH*SQMW))+4.*((SQMW+SQMZ)/SH*
1116 & (1.-3.*CTH2)+8.*SQMW*SQMZ/SH2*(2.*CTH2-1.)+
1117 & 4.*(SQMW**2+SQMZ**2)/SH2*CTH2+2.*(SQMW+SQMZ)/SH*BE2*CTH))
1119 AUWRE=(1.-XW)/SQMZ*SH/(UH-SQMW)*((CTH+BE2)**2*(3./2.-BE2/2.*CTH-
1120 & (SQMW+SQMZ)/SH+(SQMW-SQMZ)**2/(SH*SQMW))+4.*((SQMW+SQMZ)/SH*
1121 & (1.-3.*CTH2)+8.*SQMW*SQMZ/SH2*(2.*CTH2-1.)+
1122 & 4.*(SQMW**2+SQMZ**2)/SH2*CTH2-2.*(SQMW+SQMZ)/SH*BE2*CTH))
1124 A4RE=2.*(1.-XW)/SQMZ*(3.-CTH2-4.*(SQMW+SQMZ)/SH)
1126 FACH=0.5*COMFAC*1./(4096.*PARU(1)**2)*(AEM/XW)**4*(SH/SQMW)**2*
1127 & ((ASHRE+ATWRE+AUWRE+A4RE)**2+(ASHIM+ATWIM+AUWIM+A4IM)**2)
1129 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 590
1130 EI=SIGN(1.,FLOAT(I))*KCHG(IABS(I),1)
1132 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 580
1133 EJ=SIGN(1.,FLOAT(J))*KCHG(IABS(J),1)
1134 IF(EI*EJ.GT.0.) GOTO 580
1139 SIGH(NCHN)=FACH*VINT(180+I)*VINT(180+J)
1143 ELSEIF(ISUB.EQ.77) THEN
1144 C...W+/- + W+/- -> W+/- + W+/-.
1149 TH=-0.5*SH*BE2*(1.-CTH)
1150 UH=-0.5*SH*BE2*(1.+CTH)
1152 ASHRE=(SH-SQMH)/((SH-SQMH)**2+GMMH**2)*SHANG
1153 ASHIM=-GMMH/((SH-SQMH)**2+GMMH**2)*SHANG
1155 ATHRE=(TH-SQMH)/((TH-SQMH)**2+GMMH**2)*THANG
1156 ATHIM=-GMMH/((TH-SQMH)**2+GMMH**2)*THANG
1157 SGZANG=1./SQMW*BE2*(3.-BE2)**2*CTH
1160 ASZRE=(1.-XW)*SH/(SH-SQMZ)*SGZANG
1162 TGZANG=1./SQMW*(BE2*(4.-2.*BE2+BE4)+BE2*(4.-10.*BE2+BE4)*CTH+
1163 & (2.-11.*BE2+10.*BE4)*CTH2+BE2*CTH3)
1164 ATGRE=0.5*XW*SH/TH*TGZANG
1166 ATZRE=0.5*(1.-XW)*SH/(TH-SQMZ)*TGZANG
1168 A4RE=1./SQMW*(1.+2.*BE2-6.*BE2*CTH-CTH2)
1170 FACH=COMFAC*1./(4096.*PARU(1)**2)*(AEM/XW)**4*(SH/SQMW)**2*
1171 & ((ASHRE+ATHRE+ASGRE+ASZRE+ATGRE+ATZRE+A4RE)**2+
1172 & (ASHIM+ATHIM+ASGIM+ASZIM+ATGIM+ATZIM+A4IM)**2)
1174 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 610
1175 EI=SIGN(1.,FLOAT(I))*KCHG(IABS(I),1)
1177 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 600
1178 EJ=SIGN(1.,FLOAT(J))*KCHG(IABS(J),1)
1179 IF(EI*EJ.GT.0.) GOTO 600
1184 SIGH(NCHN)=FACH*VINT(180+I)*VINT(180+J)
1188 ELSEIF(ISUB.EQ.78) THEN
1189 C...W+/- + H0 -> W+/- + H0.
1191 ELSEIF(ISUB.EQ.79) THEN
1192 C...H0 + H0 -> H0 + H0.
1196 C...C: 2 -> 2, tree diagrams with masses.
1198 ELSEIF(ISUB.LE.90) THEN
1200 C...q + qb -> Q + QB.
1201 FACQQB=COMFAC*AS**2*4./9.*(((TH-SQM3)**2+
1202 & (UH-SQM3)**2)/SH2+2.*SQM3/SH)
1203 IF(MSTP(35).GE.1) THEN
1204 IF(MSTP(35).EQ.1) THEN
1209 Q2BN=SQRT(SQM3*((SQRT(SH)-2.*SQRT(SQM3))**2+PARP(36)**2))
1210 ALSSG=ULALPS_HIJING(Q2BN)
1213 XREPU=PARU(1)*ALSSG/(6.*SQRT(MAX(1E-20,1.-4.*SQM3/SH)))
1214 FREPU=XREPU/(EXP(MIN(100.,XREPU))-1.)
1219 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 620
1227 ELSEIF(ISUB.EQ.82) THEN
1228 C...g + g -> Q + QB.
1229 FACQQ1=COMFAC*FACA*AS**2*1./6.*((UH-SQM3)/(TH-SQM3)-
1230 & 2.*(UH-SQM3)**2/SH2+4.*SQM3/SH*(TH*UH-SQM3**2)/(TH-SQM3)**2)
1231 FACQQ2=COMFAC*FACA*AS**2*1./6.*((TH-SQM3)/(UH-SQM3)-
1232 & 2.*(TH-SQM3)**2/SH2+4.*SQM3/SH*(TH*UH-SQM3**2)/(UH-SQM3)**2)
1233 IF(MSTP(35).GE.1) THEN
1234 IF(MSTP(35).EQ.1) THEN
1239 Q2BN=SQRT(SQM3*((SQRT(SH)-2.*SQRT(SQM3))**2+PARP(36)**2))
1240 ALSSG=ULALPS_HIJING(Q2BN)
1243 XATTR=4.*PARU(1)*ALSSG/(3.*SQRT(MAX(1E-20,1.-4.*SQM3/SH)))
1244 FATTR=XATTR/(1.-EXP(-MIN(100.,XATTR)))
1245 XREPU=PARU(1)*ALSSG/(6.*SQRT(MAX(1E-20,1.-4.*SQM3/SH)))
1246 FREPU=XREPU/(EXP(MIN(100.,XREPU))-1.)
1247 FATRE=(2.*FATTR+5.*FREPU)/7.
1252 IF(KFAC(1,21)*KFAC(2,21).EQ.0) GOTO 630
1267 C...D: Mimimum bias processes.
1269 ELSEIF(ISUB.LE.100) THEN
1271 C...Elastic scattering.
1274 ELSEIF(ISUB.EQ.92) THEN
1275 C...Single diffractive scattering.
1278 ELSEIF(ISUB.EQ.93) THEN
1279 C...Double diffractive scattering.
1282 ELSEIF(ISUB.EQ.94) THEN
1283 C...Central diffractive scattering.
1286 ELSEIF(ISUB.EQ.95) THEN
1287 C...Low-pT scattering.
1290 ELSEIF(ISUB.EQ.96) THEN
1291 C...Multiple interactions: sum of QCD processes.
1292 CALL PYWIDT_HIJING(21,SQRT(SH),WDTP,WDTE)
1294 C...q + q' -> q + q'.
1295 FACQQ1=COMFAC*AS**2*4./9.*(SH2+UH2)/TH2
1296 FACQQB=COMFAC*AS**2*4./9.*((SH2+UH2)/TH2*FACA-
1297 & MSTP(34)*2./3.*UH2/(SH*TH))
1298 FACQQ2=COMFAC*AS**2*4./9.*((SH2+TH2)/UH2-
1299 & MSTP(34)*2./3.*SH2/(TH*UH))
1309 IF(I.EQ.-J) SIGH(NCHN)=FACQQB
1311 SIGH(NCHN)=0.5*SIGH(NCHN)
1316 SIGH(NCHN)=0.5*FACQQ2
1321 C...q + qb -> q' + qb' or g + g.
1322 FACQQB=COMFAC*AS**2*4./9.*(TH2+UH2)/SH2*(WDTE(0,1)+WDTE(0,2)+
1323 & WDTE(0,3)+WDTE(0,4))
1324 FACGG1=COMFAC*AS**2*32./27.*(UH/TH-(2.+MSTP(34)*1./4.)*UH2/SH2)
1325 FACGG2=COMFAC*AS**2*32./27.*(TH/UH-(2.+MSTP(34)*1./4.)*TH2/SH2)
1337 SIGH(NCHN)=0.5*FACGG1
1342 SIGH(NCHN)=0.5*FACGG2
1346 FACQG1=COMFAC*AS**2*4./9.*((2.+MSTP(34)*1./4.)*UH2/TH2-UH/SH)*
1348 FACQG2=COMFAC*AS**2*4./9.*((2.+MSTP(34)*1./4.)*SH2/TH2-SH/UH)
1354 ISIG(NCHN,3-ISDE)=21
1359 ISIG(NCHN,3-ISDE)=21
1365 C...g + g -> q + qb or g + g.
1366 FACQQ1=COMFAC*AS**2*1./6.*(UH/TH-(2.+MSTP(34)*1./4.)*UH2/SH2)*
1367 & (WDTE(0,1)+WDTE(0,2)+WDTE(0,3)+WDTE(0,4))*FACA
1368 FACQQ2=COMFAC*AS**2*1./6.*(TH/UH-(2.+MSTP(34)*1./4.)*TH2/SH2)*
1369 & (WDTE(0,1)+WDTE(0,2)+WDTE(0,3)+WDTE(0,4))*FACA
1370 FACGG1=COMFAC*AS**2*9./4.*(SH2/TH2+2.*SH/TH+3.+2.*TH/SH+
1372 FACGG2=COMFAC*AS**2*9./4.*(UH2/SH2+2.*UH/SH+3.+2.*SH/UH+
1374 FACGG3=COMFAC*AS**2*9./4.*(TH2/UH2+2.*TH/UH+3+2.*UH/TH+UH2/TH2)
1389 SIGH(NCHN)=0.5*FACGG1
1394 SIGH(NCHN)=0.5*FACGG2
1399 SIGH(NCHN)=0.5*FACGG3
1402 C...E: 2 -> 1, loop diagrams.
1404 ELSEIF(ISUB.LE.110) THEN
1405 IF(ISUB.EQ.101) THEN
1406 C...g + g -> gamma*/Z0.
1408 ELSEIF(ISUB.EQ.102) THEN
1410 CALL PYWIDT_HIJING(25,SQRT(SH),WDTP,WDTE)
1413 DO 690 I=1,2*MSTP(1)
1414 EPS=4.*PMAS(I,1)**2/SH
1416 IF(EPS.GT.1.E-4) THEN
1418 RLN=LOG((1.+ROOT)/(1.-ROOT))
1422 PHIRE=0.25*(RLN**2-PARU(1)**2)
1423 PHIIM=0.5*PARU(1)*RLN
1425 PHIRE=-(ASIN(1./SQRT(EPS)))**2
1428 ETARE=ETARE+0.5*EPS*(1.+(EPS-1.)*PHIRE)
1429 ETAIM=ETAIM+0.5*EPS*(EPS-1.)*PHIIM
1431 ETA2=ETARE**2+ETAIM**2
1432 FACH=COMFAC*FACA*(AS/PARU(1)*AEM/XW)**2*1./512.*
1433 & (SH/SQMW)**2*ETA2*SH2/((SH-SQMH)**2+GMMH**2)*
1434 & (WDTE(0,1)+WDTE(0,2)+WDTE(0,4))
1435 IF(KFAC(1,21)*KFAC(2,21).EQ.0) GOTO 700
1445 C...F: 2 -> 2, box diagrams.
1447 ELSEIF(ISUB.LE.120) THEN
1448 IF(ISUB.EQ.111) THEN
1449 C...f + fb -> g + H0 (q + qb -> g + H0 only).
1452 DO 710 I=1,2*MSTP(1)
1456 A5STUR=A5STUR+SQMQ/SQMH*(4.+4.*SH/(TH+UH)*(PYW1AU_HIJING(EPSS,1)
1457 $ -PYW1AU_HIJING(EPSH,1))+(1.-4.*SQMQ/(TH+UH))
1458 $ *(PYW2AU_HIJING(EPSS,1)-PYW2AU_HIJING(EPSH,1)))
1459 A5STUI=A5STUI+SQMQ/SQMH*(4.*SH/(TH+UH)*(PYW1AU_HIJING(EPSS,2)-
1460 & PYW1AU_HIJING(EPSH,2))+(1.-4.*SQMQ/(TH+UH))
1461 $ *(PYW2AU_HIJING(EPSS,2)-PYW2AU_HIJING(EPSH,2)))
1463 FACGH=COMFAC*FACA/(144.*PARU(1)**2)*AEM/XW*AS**3*SQMH/SQMW*
1464 & SQMH/SH*(UH**2+TH**2)/(UH+TH)**2*(A5STUR**2+A5STUI**2)
1465 FACGH=FACGH*WIDS(25,2)
1467 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 720
1475 ELSEIF(ISUB.EQ.112) THEN
1476 C...f + g -> f + H0 (q + g -> q + H0 only).
1479 DO 730 I=1,2*MSTP(1)
1483 A5TSUR=A5TSUR+SQMQ/SQMH*(4.+4.*TH/(SH+UH)*(PYW1AU_HIJING(EPST,1)
1484 $ -PYW1AU_HIJING(EPSH,1))+(1.-4.*SQMQ/(SH+UH))
1485 $ *(PYW2AU_HIJING(EPST,1)-PYW2AU_HIJING(EPSH,1)))
1486 A5TSUI=A5TSUI+SQMQ/SQMH*(4.*TH/(SH+UH)*(PYW1AU_HIJING(EPST,2)-
1487 & PYW1AU_HIJING(EPSH,2))+(1.-4.*SQMQ/(SH+UH))
1488 $ *(PYW2AU_HIJING(EPST,2)-PYW2AU_HIJING(EPSH,2)))
1490 FACQH=COMFAC*FACA/(384.*PARU(1)**2)*AEM/XW*AS**3*SQMH/SQMW*
1491 & SQMH/(-TH)*(UH**2+SH**2)/(UH+SH)**2*(A5TSUR**2+A5TSUI**2)
1492 FACQH=FACQH*WIDS(25,2)
1496 IF(ISDE.EQ.1.AND.KFAC(1,I)*KFAC(2,21).EQ.0) GOTO 740
1497 IF(ISDE.EQ.2.AND.KFAC(1,21)*KFAC(2,I).EQ.0) GOTO 740
1500 ISIG(NCHN,3-ISDE)=21
1506 ELSEIF(ISUB.EQ.113) THEN
1507 C...g + g -> g + H0.
1516 DO 760 I=6,2*MSTP(1)
1517 C'''Only t-quarks yet included
1523 IF(EPSH.LT.1.E-6) GOTO 760
1524 BESTU=0.5*(1.+SQRT(1.+EPSS*TH/UH))
1525 BEUST=0.5*(1.+SQRT(1.+EPSU*SH/TH))
1526 BETUS=0.5*(1.+SQRT(1.+EPST*UH/SH))
1530 W3STUR=PYI3AU_HIJING(BESTU,EPSH,1)-PYI3AU_HIJING(BESTU,EPSS,1)-
1531 & PYI3AU_HIJING(BESTU,EPSU,1)
1532 W3STUI=PYI3AU_HIJING(BESTU,EPSH,2)-PYI3AU_HIJING(BESTU,EPSS,2)-
1533 & PYI3AU_HIJING(BESTU,EPSU,2)
1534 W3SUTR=PYI3AU_HIJING(BESUT,EPSH,1)-PYI3AU_HIJING(BESUT,EPSS,1)-
1535 & PYI3AU_HIJING(BESUT,EPST,1)
1536 W3SUTI=PYI3AU_HIJING(BESUT,EPSH,2)-PYI3AU_HIJING(BESUT,EPSS,2)-
1537 & PYI3AU_HIJING(BESUT,EPST,2)
1538 W3TSUR=PYI3AU_HIJING(BETSU,EPSH,1)-PYI3AU_HIJING(BETSU,EPST,1)-
1539 & PYI3AU_HIJING(BETSU,EPSU,1)
1540 W3TSUI=PYI3AU_HIJING(BETSU,EPSH,2)-PYI3AU_HIJING(BETSU,EPST,2)-
1541 & PYI3AU_HIJING(BETSU,EPSU,2)
1542 W3TUSR=PYI3AU_HIJING(BETUS,EPSH,1)-PYI3AU_HIJING(BETUS,EPST,1)-
1543 & PYI3AU_HIJING(BETUS,EPSS,1)
1544 W3TUSI=PYI3AU_HIJING(BETUS,EPSH,2)-PYI3AU_HIJING(BETUS,EPST,2)-
1545 & PYI3AU_HIJING(BETUS,EPSS,2)
1546 W3USTR=PYI3AU_HIJING(BEUST,EPSH,1)-PYI3AU_HIJING(BEUST,EPSU,1)-
1547 & PYI3AU_HIJING(BEUST,EPST,1)
1548 W3USTI=PYI3AU_HIJING(BEUST,EPSH,2)-PYI3AU_HIJING(BEUST,EPSU,2)-
1549 & PYI3AU_HIJING(BEUST,EPST,2)
1550 W3UTSR=PYI3AU_HIJING(BEUTS,EPSH,1)-PYI3AU_HIJING(BEUTS,EPSU,1)-
1551 & PYI3AU_HIJING(BEUTS,EPSS,1)
1552 W3UTSI=PYI3AU_HIJING(BEUTS,EPSH,2)-PYI3AU_HIJING(BEUTS,EPSU,2)-
1553 & PYI3AU_HIJING(BEUTS,EPSS,2)
1554 B2STUR=SQMQ/SQMH**2*(SH*(UH-SH)/(SH+UH)+2.*TH*UH*(UH+2.*SH)/
1555 & (SH+UH)**2*(PYW1AU_HIJING(EPST,1)-PYW1AU_HIJING(EPSH,1))
1556 $ +(SQMQ-SH/4.)*(0.5*PYW2AU_HIJING(EPSS,1)+0.5
1557 $ *PYW2AU_HIJING(EPSH,1)-PYW2AU_HIJING(EPST,1)+W3STUR)+SH**2
1558 $ *(2.*SQMQ/(SH+UH)**2-0.5/(SH+UH))*(PYW2AU_HIJING(EPST,1)
1559 $ -PYW2AU_HIJING(EPSH,1))+0.5*TH*UH/SH*(PYW2AU_HIJING(EPSH,1)
1560 $ -2.*PYW2AU_HIJING(EPST,1))+0.125*(SH-12.*SQMQ-4.*TH*UH/SH)
1562 B2STUI=SQMQ/SQMH**2*(2.*TH*UH*(UH+2.*SH)/(SH+UH)**2*
1563 & (PYW1AU_HIJING(EPST,2)-PYW1AU_HIJING(EPSH,2))+(SQMQ-SH/4.)*
1564 & (0.5*PYW2AU_HIJING(EPSS,2)+0.5*PYW2AU_HIJING(EPSH,2)
1565 $ -PYW2AU_HIJING(EPST,2)+W3STUI)+SH**2*(2.*SQMQ/(SH+UH)**2-0
1566 $ .5/(SH+UH))*(PYW2AU_HIJING(EPST,2)-PYW2AU_HIJING(EPSH,2))+0
1567 $ .5*TH*UH/SH*(PYW2AU_HIJING(EPSH,2)-2.*PYW2AU_HIJING(EPST,2)
1568 $ )+0.125*(SH-12.*SQMQ-4.*TH*UH/SH)*W3TSUI)
1569 B2SUTR=SQMQ/SQMH**2*(SH*(TH-SH)/(SH+TH)+2.*UH*TH*(TH+2.*SH)/
1570 & (SH+TH)**2*(PYW1AU_HIJING(EPSU,1)-PYW1AU_HIJING(EPSH,1))
1571 $ +(SQMQ-SH/4.)*(0.5*PYW2AU_HIJING(EPSS,1)+0.5
1572 $ *PYW2AU_HIJING(EPSH,1)-PYW2AU_HIJING(EPSU,1)+W3SUTR)+SH**2
1573 $ *(2.*SQMQ/(SH+TH)**2-0.5/(SH+TH))*(PYW2AU_HIJING(EPSU,1)
1574 $ -PYW2AU_HIJING(EPSH,1))+0.5*UH*TH/SH*(PYW2AU_HIJING(EPSH,1)
1575 $ -2.*PYW2AU_HIJING(EPSU,1))+0.125*(SH-12.*SQMQ-4.*UH*TH/SH)
1577 B2SUTI=SQMQ/SQMH**2*(2.*UH*TH*(TH+2.*SH)/(SH+TH)**2*
1578 & (PYW1AU_HIJING(EPSU,2)-PYW1AU_HIJING(EPSH,2))+(SQMQ-SH/4.)*
1579 & (0.5*PYW2AU_HIJING(EPSS,2)+0.5*PYW2AU_HIJING(EPSH,2)
1580 $ -PYW2AU_HIJING(EPSU,2)+W3SUTI)+SH**2*(2.*SQMQ/(SH+TH)**2-0
1581 $ .5/(SH+TH))*(PYW2AU_HIJING(EPSU,2)-PYW2AU_HIJING(EPSH,2))+0
1582 $ .5*UH*TH/SH*(PYW2AU_HIJING(EPSH,2)-2.*PYW2AU_HIJING(EPSU,2)
1583 $ )+0.125*(SH-12.*SQMQ-4.*UH*TH/SH)*W3USTI)
1584 B2TSUR=SQMQ/SQMH**2*(TH*(UH-TH)/(TH+UH)+2.*SH*UH*(UH+2.*TH)/
1585 & (TH+UH)**2*(PYW1AU_HIJING(EPSS,1)-PYW1AU_HIJING(EPSH,1))
1586 $ +(SQMQ-TH/4.)*(0.5*PYW2AU_HIJING(EPST,1)+0.5
1587 $ *PYW2AU_HIJING(EPSH,1)-PYW2AU_HIJING(EPSS,1)+W3TSUR)+TH**2
1588 $ *(2.*SQMQ/(TH+UH)**2-0.5/(TH+UH))*(PYW2AU_HIJING(EPSS,1)
1589 $ -PYW2AU_HIJING(EPSH,1))+0.5*SH*UH/TH*(PYW2AU_HIJING(EPSH,1)
1590 $ -2.*PYW2AU_HIJING(EPSS,1))+0.125*(TH-12.*SQMQ-4.*SH*UH/TH)
1592 B2TSUI=SQMQ/SQMH**2*(2.*SH*UH*(UH+2.*TH)/(TH+UH)**2*
1593 & (PYW1AU_HIJING(EPSS,2)-PYW1AU_HIJING(EPSH,2))+(SQMQ-TH/4.)*
1594 & (0.5*PYW2AU_HIJING(EPST,2)+0.5*PYW2AU_HIJING(EPSH,2)
1595 $ -PYW2AU_HIJING(EPSS,2)+W3TSUI)+TH**2*(2.*SQMQ/(TH+UH)**2-0
1596 $ .5/(TH+UH))*(PYW2AU_HIJING(EPSS,2)-PYW2AU_HIJING(EPSH,2))+0
1597 $ .5*SH*UH/TH*(PYW2AU_HIJING(EPSH,2)-2.*PYW2AU_HIJING(EPSS,2)
1598 $ )+0.125*(TH-12.*SQMQ-4.*SH*UH/TH)*W3STUI)
1599 B2TUSR=SQMQ/SQMH**2*(TH*(SH-TH)/(TH+SH)+2.*UH*SH*(SH+2.*TH)/
1600 & (TH+SH)**2*(PYW1AU_HIJING(EPSU,1)-PYW1AU_HIJING(EPSH,1))
1601 $ +(SQMQ-TH/4.)*(0.5*PYW2AU_HIJING(EPST,1)+0.5
1602 $ *PYW2AU_HIJING(EPSH,1)-PYW2AU_HIJING(EPSU,1)+W3TUSR)+TH**2
1603 $ *(2.*SQMQ/(TH+SH)**2-0.5/(TH+SH))*(PYW2AU_HIJING(EPSU,1)
1604 $ -PYW2AU_HIJING(EPSH,1))+0.5*UH*SH/TH*(PYW2AU_HIJING(EPSH,1)
1605 $ -2.*PYW2AU_HIJING(EPSU,1))+0.125*(TH-12.*SQMQ-4.*UH*SH/TH)
1607 B2TUSI=SQMQ/SQMH**2*(2.*UH*SH*(SH+2.*TH)/(TH+SH)**2*
1608 & (PYW1AU_HIJING(EPSU,2)-PYW1AU_HIJING(EPSH,2))+(SQMQ-TH/4.)*
1609 & (0.5*PYW2AU_HIJING(EPST,2)+0.5*PYW2AU_HIJING(EPSH,2)
1610 $ -PYW2AU_HIJING(EPSU,2)+W3TUSI)+TH**2*(2.*SQMQ/(TH+SH)**2-0
1611 $ .5/(TH+SH))*(PYW2AU_HIJING(EPSU,2)-PYW2AU_HIJING(EPSH,2))+0
1612 $ .5*UH*SH/TH*(PYW2AU_HIJING(EPSH,2)-2.*PYW2AU_HIJING(EPSU,2)
1613 $ )+0.125*(TH-12.*SQMQ-4.*UH*SH/TH)*W3UTSI)
1614 B2USTR=SQMQ/SQMH**2*(UH*(TH-UH)/(UH+TH)+2.*SH*TH*(TH+2.*UH)/
1615 & (UH+TH)**2*(PYW1AU_HIJING(EPSS,1)-PYW1AU_HIJING(EPSH,1))
1616 $ +(SQMQ-UH/4.)*(0.5*PYW2AU_HIJING(EPSU,1)+0.5
1617 $ *PYW2AU_HIJING(EPSH,1)-PYW2AU_HIJING(EPSS,1)+W3USTR)+UH**2
1618 $ *(2.*SQMQ/(UH+TH)**2-0.5/(UH+TH))*(PYW2AU_HIJING(EPSS,1)
1619 $ -PYW2AU_HIJING(EPSH,1))+0.5*SH*TH/UH*(PYW2AU_HIJING(EPSH,1)
1620 $ -2.*PYW2AU_HIJING(EPSS,1))+0.125*(UH-12.*SQMQ-4.*SH*TH/UH)
1622 B2USTI=SQMQ/SQMH**2*(2.*SH*TH*(TH+2.*UH)/(UH+TH)**2*
1623 & (PYW1AU_HIJING(EPSS,2)-PYW1AU_HIJING(EPSH,2))+(SQMQ-UH/4.)*
1624 & (0.5*PYW2AU_HIJING(EPSU,2)+0.5*PYW2AU_HIJING(EPSH,2)
1625 $ -PYW2AU_HIJING(EPSS,2)+W3USTI)+UH**2*(2.*SQMQ/(UH+TH)**2-0
1626 $ .5/(UH+TH))*(PYW2AU_HIJING(EPSS,2)-PYW2AU_HIJING(EPSH,2))+0
1627 $ .5*SH*TH/UH*(PYW2AU_HIJING(EPSH,2)-2.*PYW2AU_HIJING(EPSS,2)
1628 $ )+0.125*(UH-12.*SQMQ-4.*SH*TH/UH)*W3SUTI)
1629 B2UTSR=SQMQ/SQMH**2*(UH*(SH-UH)/(UH+SH)+2.*TH*SH*(SH+2.*UH)/
1630 & (UH+SH)**2*(PYW1AU_HIJING(EPST,1)-PYW1AU_HIJING(EPSH,1))
1631 $ +(SQMQ-UH/4.)*(0.5*PYW2AU_HIJING(EPSU,1)+0.5
1632 $ *PYW2AU_HIJING(EPSH,1)-PYW2AU_HIJING(EPST,1)+W3UTSR)+UH**2
1633 $ *(2.*SQMQ/(UH+SH)**2-0.5/(UH+SH))*(PYW2AU_HIJING(EPST,1)
1634 $ -PYW2AU_HIJING(EPSH,1))+0.5*TH*SH/UH*(PYW2AU_HIJING(EPSH,1)
1635 $ -2.*PYW2AU_HIJING(EPST,1))+0.125*(UH-12.*SQMQ-4.*TH*SH/UH)
1637 B2UTSI=SQMQ/SQMH**2*(2.*TH*SH*(SH+2.*UH)/(UH+SH)**2*
1638 & (PYW1AU_HIJING(EPST,2)-PYW1AU_HIJING(EPSH,2))+(SQMQ-UH/4.)*
1639 & (0.5*PYW2AU_HIJING(EPSU,2)+0.5*PYW2AU_HIJING(EPSH,2)
1640 $ -PYW2AU_HIJING(EPST,2)+W3UTSI)+UH**2*(2.*SQMQ/(UH+SH)**2-0
1641 $ .5/(UH+SH))*(PYW2AU_HIJING(EPST,2)-PYW2AU_HIJING(EPSH,2))+0
1642 $ .5*TH*SH/UH*(PYW2AU_HIJING(EPSH,2)-2.*PYW2AU_HIJING(EPST,2)
1643 $ )+0.125*(UH-12.*SQMQ-4.*TH*SH/UH)*W3TUSI)
1644 B4STUR=SQMQ/SQMH*(-2./3.+(SQMQ/SQMH-1./4.)*(PYW2AU_HIJING(EPSS,1
1645 $ )-PYW2AU_HIJING(EPSH,1)+W3STUR))
1646 B4STUI=SQMQ/SQMH*(SQMQ/SQMH-1./4.)*(PYW2AU_HIJING(EPSS,2)-
1647 & PYW2AU_HIJING(EPSH,2)+W3STUI)
1648 B4TUSR=SQMQ/SQMH*(-2./3.+(SQMQ/SQMH-1./4.)*(PYW2AU_HIJING(EPST,1
1649 $ )-PYW2AU_HIJING(EPSH,1)+W3TUSR))
1650 B4TUSI=SQMQ/SQMH*(SQMQ/SQMH-1./4.)*(PYW2AU_HIJING(EPST,2)-
1651 & PYW2AU_HIJING(EPSH,2)+W3TUSI)
1652 B4USTR=SQMQ/SQMH*(-2./3.+(SQMQ/SQMH-1./4.)*(PYW2AU_HIJING(EPSU,1
1653 $ )-PYW2AU_HIJING(EPSH,1)+W3USTR))
1654 B4USTI=SQMQ/SQMH*(SQMQ/SQMH-1./4.)*(PYW2AU_HIJING(EPSU,2)-
1655 & PYW2AU_HIJING(EPSH,2)+W3USTI)
1656 A2STUR=A2STUR+B2STUR+B2SUTR
1657 A2STUI=A2STUI+B2STUI+B2SUTI
1658 A2USTR=A2USTR+B2USTR+B2UTSR
1659 A2USTI=A2USTI+B2USTI+B2UTSI
1660 A2TUSR=A2TUSR+B2TUSR+B2TSUR
1661 A2TUSI=A2TUSI+B2TUSI+B2TSUI
1662 A4STUR=A4STUR+B4STUR+B4USTR+B4TUSR
1663 A4STUI=A4STUI+B4STUI+B4USTI+B4TUSI
1665 FACGH=COMFAC*FACA*3./(128.*PARU(1)**2)*AEM/XW*AS**3*
1666 & SQMH/SQMW*SQMH**3/(SH*TH*UH)*(A2STUR**2+A2STUI**2+A2USTR**2+
1667 & A2USTI**2+A2TUSR**2+A2TUSI**2+A4STUR**2+A4STUI**2)
1668 FACGH=FACGH*WIDS(25,2)
1669 IF(KFAC(1,21)*KFAC(2,21).EQ.0) GOTO 770
1677 ELSEIF(ISUB.EQ.114) THEN
1678 C...g + g -> gamma + gamma.
1681 DO 780 I=1,2*MSTP(1)
1682 EI=KCHG(IABS(I),1)/3.
1687 IF(EPSS+ABS(EPST)+ABS(EPSU).LT.3.E-6) THEN
1688 A0STUR=1.+(TH-UH)/SH*LOG(TH/UH)+0.5*(TH2+UH2)/SH2*
1689 & (LOG(TH/UH)**2+PARU(1)**2)
1691 A0TSUR=1.+(SH-UH)/TH*LOG(-SH/UH)+0.5*(SH2+UH2)/TH2*
1693 A0TSUI=-PARU(1)*((SH-UH)/TH+(SH2+UH2)/TH2*LOG(-SH/UH))
1694 A0UTSR=1.+(TH-SH)/UH*LOG(-TH/SH)+0.5*(TH2+SH2)/UH2*
1696 A0UTSI=PARU(1)*((TH-SH)/UH+(TH2+SH2)/UH2*LOG(-TH/SH))
1702 BESTU=0.5*(1.+SQRT(1.+EPSS*TH/UH))
1703 BEUST=0.5*(1.+SQRT(1.+EPSU*SH/TH))
1704 BETUS=0.5*(1.+SQRT(1.+EPST*UH/SH))
1708 A0STUR=1.+(1.+2.*TH/SH)*PYW1AU_HIJING(EPST,1)+(1.+2.*UH/SH)*
1709 & PYW1AU_HIJING(EPSU,1)+0.5*((TH2+UH2)/SH2-EPSS)
1710 $ *(PYW2AU_HIJING(EPST,1)+PYW2AU_HIJING(EPSU,1))-0.25*EPST
1711 $ *(1.-0.5*EPSS)*(PYI3AU_HIJING(BESUT,EPSS,1)
1712 $ +PYI3AU_HIJING(BESUT,EPST,1))-0.25*EPSU*(1.-0.5*EPSS)
1713 $ *(PYI3AU_HIJING(BESTU,EPSS,1)+PYI3AU_HIJING(BESTU,EPSU,1)
1714 $ )+0.25*(-2.*(TH2+UH2)/SH2+4.*EPSS+EPST+EPSU+0.5*EPST*EPSU
1715 $ )*(PYI3AU_HIJING(BETSU,EPST,1)+PYI3AU_HIJING(BETSU,EPSU,1
1717 A0STUI=(1.+2.*TH/SH)*PYW1AU_HIJING(EPST,2)+(1.+2.*UH/SH)*
1718 & PYW1AU_HIJING(EPSU,2)+0.5*((TH2+UH2)/SH2-EPSS)
1719 $ *(PYW2AU_HIJING(EPST,2)+PYW2AU_HIJING(EPSU,2))-0.25*EPST
1720 $ *(1.-0.5*EPSS)*(PYI3AU_HIJING(BESUT,EPSS,2)
1721 $ +PYI3AU_HIJING(BESUT,EPST,2))-0.25*EPSU*(1.-0.5*EPSS)
1722 $ *(PYI3AU_HIJING(BESTU,EPSS,2)+PYI3AU_HIJING(BESTU,EPSU,2)
1723 $ )+0.25*(-2.*(TH2+UH2)/SH2+4.*EPSS+EPST+EPSU+0.5*EPST*EPSU
1724 $ )*(PYI3AU_HIJING(BETSU,EPST,2)+PYI3AU_HIJING(BETSU,EPSU,2
1726 A0TSUR=1.+(1.+2.*SH/TH)*PYW1AU_HIJING(EPSS,1)+(1.+2.*UH/TH)*
1727 & PYW1AU_HIJING(EPSU,1)+0.5*((SH2+UH2)/TH2-EPST)
1728 $ *(PYW2AU_HIJING(EPSS,1)+PYW2AU_HIJING(EPSU,1))-0.25*EPSS
1729 $ *(1.-0.5*EPST)*(PYI3AU_HIJING(BETUS,EPST,1)
1730 $ +PYI3AU_HIJING(BETUS,EPSS,1))-0.25*EPSU*(1.-0.5*EPST)
1731 $ *(PYI3AU_HIJING(BETSU,EPST,1)+PYI3AU_HIJING(BETSU,EPSU,1)
1732 $ )+0.25*(-2.*(SH2+UH2)/TH2+4.*EPST+EPSS+EPSU+0.5*EPSS*EPSU
1733 $ )*(PYI3AU_HIJING(BESTU,EPSS,1)+PYI3AU_HIJING(BESTU,EPSU,1
1735 A0TSUI=(1.+2.*SH/TH)*PYW1AU_HIJING(EPSS,2)+(1.+2.*UH/TH)*
1736 & PYW1AU_HIJING(EPSU,2)+0.5*((SH2+UH2)/TH2-EPST)
1737 $ *(PYW2AU_HIJING(EPSS,2)+PYW2AU_HIJING(EPSU,2))-0.25*EPSS
1738 $ *(1.-0.5*EPST)*(PYI3AU_HIJING(BETUS,EPST,2)
1739 $ +PYI3AU_HIJING(BETUS,EPSS,2))-0.25*EPSU*(1.-0.5*EPST)
1740 $ *(PYI3AU_HIJING(BETSU,EPST,2)+PYI3AU_HIJING(BETSU,EPSU,2)
1741 $ )+0.25*(-2.*(SH2+UH2)/TH2+4.*EPST+EPSS+EPSU+0.5*EPSS*EPSU
1742 $ )*(PYI3AU_HIJING(BESTU,EPSS,2)+PYI3AU_HIJING(BESTU,EPSU,2
1744 A0UTSR=1.+(1.+2.*TH/UH)*PYW1AU_HIJING(EPST,1)+(1.+2.*SH/UH)*
1745 & PYW1AU_HIJING(EPSS,1)+0.5*((TH2+SH2)/UH2-EPSU)
1746 $ *(PYW2AU_HIJING(EPST,1)+PYW2AU_HIJING(EPSS,1))-0.25*EPST
1747 $ *(1.-0.5*EPSU)*(PYI3AU_HIJING(BEUST,EPSU,1)
1748 $ +PYI3AU_HIJING(BEUST,EPST,1))-0.25*EPSS*(1.-0.5*EPSU)
1749 $ *(PYI3AU_HIJING(BEUTS,EPSU,1)+PYI3AU_HIJING(BEUTS,EPSS,1)
1750 $ )+0.25*(-2.*(TH2+SH2)/UH2+4.*EPSU+EPST+EPSS+0.5*EPST*EPSS
1751 $ )*(PYI3AU_HIJING(BETUS,EPST,1)+PYI3AU_HIJING(BETUS,EPSS,1
1753 A0UTSI=(1.+2.*TH/UH)*PYW1AU_HIJING(EPST,2)+(1.+2.*SH/UH)*
1754 & PYW1AU_HIJING(EPSS,2)+0.5*((TH2+SH2)/UH2-EPSU)
1755 $ *(PYW2AU_HIJING(EPST,2)+PYW2AU_HIJING(EPSS,2))-0.25*EPST
1756 $ *(1.-0.5*EPSU)*(PYI3AU_HIJING(BEUST,EPSU,2)
1757 $ +PYI3AU_HIJING(BEUST,EPST,2))-0.25*EPSS*(1.-0.5*EPSU)
1758 $ *(PYI3AU_HIJING(BEUTS,EPSU,2)+PYI3AU_HIJING(BEUTS,EPSS,2)
1759 $ )+0.25*(-2.*(TH2+SH2)/UH2+4.*EPSU+EPST+EPSS+0.5*EPST*EPSS
1760 $ )*(PYI3AU_HIJING(BETUS,EPST,2)+PYI3AU_HIJING(BETUS,EPSS,2
1762 A1STUR=-1.-0.25*(EPSS+EPST+EPSU)*(PYW2AU_HIJING(EPSS,1)+
1763 & PYW2AU_HIJING(EPST,1)+PYW2AU_HIJING(EPSU,1))+0.25*(EPSU+0
1764 $ .5*EPSS*EPST)*(PYI3AU_HIJING(BESUT,EPSS,1)
1765 $ +PYI3AU_HIJING(BESUT,EPST,1))+0.25*(EPST+0.5*EPSS*EPSU)
1766 $ *(PYI3AU_HIJING(BESTU,EPSS,1)+PYI3AU_HIJING(BESTU,EPSU,1)
1767 $ )+0.25*(EPSS+0.5*EPST*EPSU)*(PYI3AU_HIJING(BETSU,EPST,1)
1768 $ +PYI3AU_HIJING(BETSU,EPSU,1))
1769 A1STUI=-0.25*(EPSS+EPST+EPSU)*(PYW2AU_HIJING(EPSS,2)
1770 $ +PYW2AU_HIJING(EPST,2)+PYW2AU_HIJING(EPSU,2))+0.25*(EPSU
1771 $ +0.5*EPSS*EPST)*(PYI3AU_HIJING(BESUT,EPSS,2)
1772 $ +PYI3AU_HIJING(BESUT,EPST,2))+0.25*(EPST+0.5*EPSS*EPSU)
1773 $ *(PYI3AU_HIJING(BESTU,EPSS,2)+PYI3AU_HIJING(BESTU,EPSU,2)
1774 $ )+0.25*(EPSS+0.5*EPST*EPSU)*(PYI3AU_HIJING(BETSU,EPST,2)
1775 $ +PYI3AU_HIJING(BETSU,EPSU,2))
1776 A2STUR=-1.+0.125*EPSS*EPST*(PYI3AU_HIJING(BESUT,EPSS,1)+
1777 & PYI3AU_HIJING(BESUT,EPST,1))+0.125*EPSS*EPSU
1778 $ *(PYI3AU_HIJING(BESTU,EPSS,1)+PYI3AU_HIJING(BESTU,EPSU,1)
1779 $ )+0.125*EPST*EPSU*(PYI3AU_HIJING(BETSU,EPST,1)
1780 $ +PYI3AU_HIJING(BETSU,EPSU,1))
1781 A2STUI=0.125*EPSS*EPST*(PYI3AU_HIJING(BESUT,EPSS,2)+
1782 & PYI3AU_HIJING(BESUT,EPST,2))+0.125*EPSS*EPSU
1783 $ *(PYI3AU_HIJING(BESTU,EPSS,2)+PYI3AU_HIJING(BESTU,EPSU,2)
1784 $ )+0.125*EPST*EPSU*(PYI3AU_HIJING(BETSU,EPST,2)
1785 $ +PYI3AU_HIJING(BETSU,EPSU,2))
1787 ASRE=ASRE+EI**2*(A0STUR+A0TSUR+A0UTSR+4.*A1STUR+A2STUR)
1788 ASIM=ASIM+EI**2*(A0STUI+A0TSUI+A0UTSI+4.*A1STUI+A2STUI)
1790 FACGG=COMFAC*FACA/(8.*PARU(1)**2)*AS**2*AEM**2*(ASRE**2+ASIM**2)
1791 IF(KFAC(1,21)*KFAC(2,21).EQ.0) GOTO 790
1799 ELSEIF(ISUB.EQ.115) THEN
1800 C...g + g -> gamma + Z0.
1802 ELSEIF(ISUB.EQ.116) THEN
1803 C...g + g -> Z0 + Z0.
1805 ELSEIF(ISUB.EQ.117) THEN
1806 C...g + g -> W+ + W-.
1810 C...G: 2 -> 3, tree diagrams.
1812 ELSEIF(ISUB.LE.140) THEN
1813 IF(ISUB.EQ.121) THEN
1814 C...g + g -> f + fb + H0.
1818 C...H: 2 -> 1, tree diagrams, non-standard model processes.
1820 ELSEIF(ISUB.LE.160) THEN
1821 IF(ISUB.EQ.141) THEN
1822 C...f + fb -> gamma*/Z0/Z'0.
1824 CALL PYWIDT_HIJING(32,SQRT(SH),WDTP,WDTE)
1825 FACZP=COMFAC*AEM**2*4./9.
1827 IF(I.EQ.0.OR.KFAC(1,I)*KFAC(2,-I).EQ.0) GOTO 800
1828 EI=KCHG(IABS(I),1)/3.
1837 SIGH(NCHN)=FACZP*(EI**2*VINT(111)+EI*VI/(8.*XW*(1.-XW))*
1838 & SH*(SH-SQMZ)/((SH-SQMZ)**2+GMMZ**2)*VINT(112)+EI*VPI/(8.*XW*
1839 & (1.-XW))*SH*(SH-SQMZP)/((SH-SQMZP)**2+GMMZP**2)*VINT(113)+
1840 & (VI**2+AI**2)/(16.*XW*(1.-XW))**2*SH2/((SH-SQMZ)**2+GMMZ**2)*
1841 & VINT(114)+2.*(VI*VPI+AI*API)/(16.*XW*(1.-XW))**2*SH2*
1842 & ((SH-SQMZ)*(SH-SQMZP)+GMMZ*GMMZP)/(((SH-SQMZ)**2+GMMZ**2)*
1843 & ((SH-SQMZP)**2+GMMZP**2))*VINT(115)+(VPI**2+API**2)/
1844 & (16.*XW*(1.-XW))**2*SH2/((SH-SQMZP)**2+GMMZP**2)*VINT(116))
1847 ELSEIF(ISUB.EQ.142) THEN
1848 C...f + fb' -> H+/-.
1849 CALL PYWIDT_HIJING(37,SQRT(SH),WDTP,WDTE)
1850 FHC=COMFAC*(AEM/XW)**2*1./48.*(SH/SQMW)**2*SH2/
1851 & ((SH-SQMHC)**2+GMMHC**2)
1852 C'''No construction yet for leptons
1853 DO 840 I=1,MSTP(54)/2
1856 RMQL=PMAS(IL,1)**2/SH
1857 RMQU=PMAS(IU,1)**2/SH
1858 FACHC=FHC*((RMQL*PARU(121)+RMQU/PARU(121))*(1.-RMQL-RMQU)-
1859 & 4.*RMQL*RMQU)/SQRT(MAX(0.,(1.-RMQL-RMQU)**2-4.*RMQL*RMQU))
1860 IF(KFAC(1,IL)*KFAC(2,-IU).EQ.0) GOTO 810
1861 KCHHC=(KCHG(IL,1)-KCHG(IU,1))/3
1866 SIGH(NCHN)=FACHC*(WDTE(0,1)+WDTE(0,(5-KCHHC)/2)+WDTE(0,4))
1867 810 IF(KFAC(1,-IL)*KFAC(2,IU).EQ.0) GOTO 820
1868 KCHHC=(-KCHG(IL,1)+KCHG(IU,1))/3
1873 SIGH(NCHN)=FACHC*(WDTE(0,1)+WDTE(0,(5-KCHHC)/2)+WDTE(0,4))
1874 820 IF(KFAC(1,IU)*KFAC(2,-IL).EQ.0) GOTO 830
1875 KCHHC=(KCHG(IU,1)-KCHG(IL,1))/3
1880 SIGH(NCHN)=FACHC*(WDTE(0,1)+WDTE(0,(5-KCHHC)/2)+WDTE(0,4))
1881 830 IF(KFAC(1,-IU)*KFAC(2,IL).EQ.0) GOTO 840
1882 KCHHC=(-KCHG(IU,1)+KCHG(IL,1))/3
1887 SIGH(NCHN)=FACHC*(WDTE(0,1)+WDTE(0,(5-KCHHC)/2)+WDTE(0,4))
1890 ELSEIF(ISUB.EQ.143) THEN
1892 CALL PYWIDT_HIJING(40,SQRT(SH),WDTP,WDTE)
1893 FACR=COMFAC*(AEM/XW)**2*1./9.*SH2/((SH-SQMR)**2+GMMR**2)
1895 IF(I.EQ.0.OR.KFAC(1,I).EQ.0) GOTO 860
1898 IF(J.EQ.0.OR.KFAC(2,J).EQ.0) GOTO 850
1900 IF(I*J.GT.0.OR.IABS(IA-JA).NE.2) GOTO 850
1905 SIGH(NCHN)=FACR*(WDTE(0,1)+WDTE(0,(10-(I+J))/4)+WDTE(0,4))
1911 C...I: 2 -> 2, tree diagrams, non-standard model processes.
1914 IF(ISUB.EQ.161) THEN
1915 C...f + g -> f' + H+/- (q + g -> q' + H+/- only).
1916 FHCQ=COMFAC*FACA*AS*AEM/XW*1./24
1920 FACHCQ=FHCQ/PARU(121)*SQMQ/SQMW*(SH/(SQMQ-UH)+
1921 & 2.*SQMQ*(SQMHC-UH)/(SQMQ-UH)**2+(SQMQ-UH)/SH+
1922 & 2.*SQMQ/(SQMQ-UH)+2.*(SQMHC-UH)/(SQMQ-UH)*(SQMHC-SQMQ-SH)/SH)
1923 IF(KFAC(1,-I)*KFAC(2,21).EQ.0) GOTO 870
1924 KCHHC=ISIGN(1,-KCHG(I,1))
1929 SIGH(NCHN)=FACHCQ*(WDTE(0,1)+WDTE(0,(5-KCHHC)/2)+WDTE(0,4))
1930 870 IF(KFAC(1,I)*KFAC(2,21).EQ.0) GOTO 880
1931 KCHHC=ISIGN(1,KCHG(I,1))
1936 SIGH(NCHN)=FACHCQ*(WDTE(0,1)+WDTE(0,(5-KCHHC)/2)+WDTE(0,4))
1937 880 IF(KFAC(1,21)*KFAC(2,-I).EQ.0) GOTO 890
1938 KCHHC=ISIGN(1,-KCHG(I,1))
1943 SIGH(NCHN)=FACHCQ*(WDTE(0,1)+WDTE(0,(5-KCHHC)/2)+WDTE(0,4))
1944 890 IF(KFAC(1,21)*KFAC(2,I).EQ.0) GOTO 900
1945 KCHHC=ISIGN(1,KCHG(I,1))
1950 SIGH(NCHN)=FACHCQ*(WDTE(0,1)+WDTE(0,(5-KCHHC)/2)+WDTE(0,4))
1956 C...Multiply with structure functions.
1957 IF(ISUB.LE.90.OR.ISUB.GE.96) THEN
1959 IF(MINT(41).EQ.2) THEN
1961 IF(KFL1.EQ.21) KFL1=0
1962 SIGH(ICHN)=SIGH(ICHN)*XSFX(1,KFL1)
1964 IF(MINT(42).EQ.2) THEN
1966 IF(KFL2.EQ.21) KFL2=0
1967 SIGH(ICHN)=SIGH(ICHN)*XSFX(2,KFL2)
1969 910 SIGS=SIGS+SIGH(ICHN)