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Commit | Line | Data |
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e74335a4 | 1 | * $Id$ |
2 | ||
3 | C********************************************************************* | |
4 | ||
5 | SUBROUTINE PYXTOT_HIJING | |
6 | ||
7 | C...Parametrizes total, double diffractive, single diffractive and | |
8 | C...elastic cross-sections for different energies and beams. | |
9 | #include "ludat1_hijing.inc" | |
10 | #include "pypars_hijing.inc" | |
11 | #include "pyint1_hijing.inc" | |
12 | #include "pyint5_hijing.inc" | |
13 | DIMENSION BCS(5,8),BCB(2,5),BCC(3) | |
14 | ||
15 | C...The following data lines are coefficients needed in the | |
16 | C...Block, Cahn parametrization of total cross-section and nuclear | |
17 | C...slope parameter; see below. | |
18 | DATA ((BCS(I,J),J=1,8),I=1,5)/ | |
19 | 1 41.74, 0.66, 0.0000, 337., 0.0, 0.0, -39.3, 0.48, | |
20 | 2 41.66, 0.60, 0.0000, 306., 0.0, 0.0, -34.6, 0.51, | |
21 | 3 41.36, 0.63, 0.0000, 299., 7.3, 0.5, -40.4, 0.47, | |
22 | 4 41.68, 0.63, 0.0083, 330., 0.0, 0.0, -39.0, 0.48, | |
23 | 5 41.13, 0.59, 0.0074, 278., 10.5, 0.5, -41.2, 0.46/ | |
24 | DATA ((BCB(I,J),J=1,5),I=1,2)/ | |
25 | 1 10.79, -0.049, 0.040, 21.5, 1.23, | |
26 | 2 9.92, -0.027, 0.013, 18.9, 1.07/ | |
27 | DATA BCC/2.0164346,-0.5590311,0.0376279/ | |
28 | ||
29 | C...Total cross-section and nuclear slope parameter for pp and p-pbar | |
30 | NFIT=MIN(5,MAX(1,MSTP(31))) | |
31 | SIGP=BCS(NFIT,1)+BCS(NFIT,2)*(-0.25*PARU(1)**2* | |
32 | &(1.-0.25*BCS(NFIT,3)*PARU(1)**2)+(1.+0.5*BCS(NFIT,3)*PARU(1)**2)* | |
33 | &(LOG(VINT(2)/BCS(NFIT,4)))**2+BCS(NFIT,3)* | |
34 | &(LOG(VINT(2)/BCS(NFIT,4)))**4)/ | |
35 | &((1.-0.25*BCS(NFIT,3)*PARU(1)**2)**2+2.*BCS(NFIT,3)* | |
36 | &(1.+0.25*BCS(NFIT,3)*PARU(1)**2)*(LOG(VINT(2)/BCS(NFIT,4)))**2+ | |
37 | &BCS(NFIT,3)**2*(LOG(VINT(2)/BCS(NFIT,4)))**4)+BCS(NFIT,5)* | |
38 | &VINT(2)**(BCS(NFIT,6)-1.)*SIN(0.5*PARU(1)*BCS(NFIT,6)) | |
39 | SIGM=-BCS(NFIT,7)*VINT(2)**(BCS(NFIT,8)-1.)* | |
40 | &COS(0.5*PARU(1)*BCS(NFIT,8)) | |
41 | REFP=BCS(NFIT,2)*PARU(1)*LOG(VINT(2)/BCS(NFIT,4))/ | |
42 | &((1.-0.25*BCS(NFIT,3)*PARU(1)**2)**2+2.*BCS(NFIT,3)* | |
43 | &(1.+0.25*BCS(NFIT,3)*PARU(1)**2)+(LOG(VINT(2)/BCS(NFIT,4)))**2+ | |
44 | &BCS(NFIT,3)**2*(LOG(VINT(2)/BCS(NFIT,4)))**4)-BCS(NFIT,5)* | |
45 | &VINT(2)**(BCS(NFIT,6)-1.)*COS(0.5*PARU(1)*BCS(NFIT,6)) | |
46 | REFM=-BCS(NFIT,7)*VINT(2)**(BCS(NFIT,8)-1.)* | |
47 | &SIN(0.5*PARU(1)*BCS(NFIT,8)) | |
48 | SIGMA=SIGP-ISIGN(1,MINT(11)*MINT(12))*SIGM | |
49 | RHO=(REFP-ISIGN(1,MINT(11)*MINT(12))*REFM)/SIGMA | |
50 | ||
51 | C...Nuclear slope parameter B, curvature C: | |
52 | NFIT=1 | |
53 | IF(MSTP(31).GE.4) NFIT=2 | |
54 | BP=BCB(NFIT,1)+BCB(NFIT,2)*LOG(VINT(2))+ | |
55 | &BCB(NFIT,3)*(LOG(VINT(2)))**2 | |
56 | BM=BCB(NFIT,4)+BCB(NFIT,5)*LOG(VINT(2)) | |
57 | B=BP-ISIGN(1,MINT(11)*MINT(12))*SIGM/SIGP*(BM-BP) | |
58 | VINT(121)=B | |
59 | C=-0.5*BCC(2)/BCC(3)*(1.-SQRT(MAX(0.,1.+4.*BCC(3)/BCC(2)**2* | |
60 | &(1.E-03*VINT(1)-BCC(1))))) | |
61 | VINT(122)=C | |
62 | ||
63 | C...Elastic scattering cross-section (fixed by sigma-tot, rho and B). | |
64 | SIGEL=SIGMA**2*(1.+RHO**2)/(16.*PARU(1)*PARU(5)*B) | |
65 | ||
66 | C...Single diffractive scattering cross-section from Goulianos: | |
67 | SIGSD=2.*0.68*(1.+36./VINT(2))*LOG(0.6+0.1*VINT(2)) | |
68 | ||
69 | C...Double diffractive scattering cross-section (essentially fixed by | |
70 | C...sigma-sd and sigma-el). | |
71 | SIGDD=SIGSD**2/(3.*SIGEL) | |
72 | ||
73 | C...Total non-elastic, non-diffractive cross-section. | |
74 | SIGND=SIGMA-SIGDD-SIGSD-SIGEL | |
75 | ||
76 | C...Rescale for pions. | |
77 | IF(IABS(MINT(11)).EQ.211.AND.IABS(MINT(12)).EQ.211) THEN | |
78 | SIGMA=4./9.*SIGMA | |
79 | SIGDD=4./9.*SIGDD | |
80 | SIGSD=4./9.*SIGSD | |
81 | SIGEL=4./9.*SIGEL | |
82 | SIGND=4./9.*SIGND | |
83 | ELSEIF(IABS(MINT(11)).EQ.211.OR.IABS(MINT(12)).EQ.211) THEN | |
84 | SIGMA=2./3.*SIGMA | |
85 | SIGDD=2./3.*SIGDD | |
86 | SIGSD=2./3.*SIGSD | |
87 | SIGEL=2./3.*SIGEL | |
88 | SIGND=2./3.*SIGND | |
89 | ENDIF | |
90 | ||
91 | C...Save cross-sections in common block PYPARA. | |
92 | VINT(101)=SIGMA | |
93 | VINT(102)=SIGEL | |
94 | VINT(103)=SIGSD | |
95 | VINT(104)=SIGDD | |
96 | VINT(106)=SIGND | |
97 | XSEC(95,1)=SIGND | |
98 | ||
99 | RETURN | |
100 | END |