5 * Revision 1.4 2000/09/18 10:02:35 hristov
6 * Makefile added to PDF8
8 * Revision 1.1.1.2 1996/10/30 08:32:35 cernlib
11 * Revision 1.2 1996/10/28 15:02:12 pdflib
12 * PDFLIB new version 7.04
14 * Revision 1.1.1.1 1996/04/12 15:29:23 plothow
18 #include "pdf/pilot.h"
19 SUBROUTINE GRVGAH0 (ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL)
20 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
22 * G R V - P H O T O N - P A R A M E T R I Z A T I O N S *
24 * FOR A DETAILED EXPLANATION SEE : *
25 * M. GLUECK, E.REYA, A.VOGT: DO-TH 91/31 *
27 * THE OUTPUT IS ALWAYS 1./ ALPHA(EM) * X * PARTON DENSITY *
28 * output modified by HPB to be always X * PARTON DENSITY *
30 * THE PARAMETRIZATIONS ARE FITTED TO THE PARTON DISTRIBUTIONS *
31 * FOR Q ** 2 BETWEEN MU ** 2 (= 0.25 / 0.30 GEV ** 2 IN LO *
32 * / HO) AND 1.E6 GEV ** 2 AND FOR X BETWEEN 1.E-5 AND 1. *
34 * HEAVY QUARK THRESHOLDS Q(H) = M(H) : *
35 * M(C) = 1.5, M(B) = 4.5, M(T) = 100 GEV *
37 * CORRESPONDING LAMBDA(F) VALUES FOR F ACTIVE FLAVOURS : *
38 * LO : LAMBDA(3) = 0.232, LAMBDA(4) = 0.200, *
39 * LAMBDA(5) = 0.153, LAMBDA(6) = 0.082 GEV *
40 * HO : LAMBDA(3) = 0.248, LAMBDA(4) = 0.200, *
41 * LAMBDA(5) = 0.131, LAMBDA(6) = 0.053 GEV *
43 * HO DISTRIBUTIONS REFER TO THE DIS(GAMMA) SCHEME, SEE : *
44 * M. GLUECK, E.REYA, A.VOGT: DO-TH 91/26 *
46 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
49 #if defined(CERNLIB_DOUBLE)
52 #if defined(CERNLIB_SINGLE)
55 + ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL
57 DATA ALPHEM/7.29927D-3/
63 S = ALOG (ALOG(Q2/LAM2) / ALOG(MU2/LAM2))
66 C...X * U = X * UBAR :
69 AK = 0.527 + 0.200 * S - 0.107 * S2
70 BK = 7.106 - 0.310 * SS - 0.786 * S2
71 AG = 0.197 + 0.533 * S
72 BG = 0.062 - 0.398 * S + 0.109 * S2
73 C = 0.755 * S - 0.112 * S2
76 ES = 1.752 + 0.866 * S
77 U0 = GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
80 C...X * D = X * DBAR :
83 AK = 0.500 + 0.067 * SS - 0.055 * S2
84 BK = 0.376 - 0.453 * SS + 0.405 * S2
85 AG = 0.156 + 0.184 * S
86 BG = 0.0 - 0.528 * S + 0.146 * S2
88 D = 0.379 - 0.301 * S + 0.081 * S2
90 ES = 1.645 + 1.016 * S
91 D0 = GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
97 AK = 0.537 - 0.600 * SS
98 BK = 6.389 - 0.953 * S2
99 AG = 0.558 - 0.383 * SS + 0.261 * S2
101 C = -0.222 + 0.078 * S2
102 D = 0.153 + 0.978 * S - 0.209 * S2
103 E = 1.429 + 1.772 * S
104 ES = 3.331 + 0.806 * S
105 G0 = GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
107 C...X * S = X * SBAR :
111 AK = 0.622 + 0.332 * S - 0.300 * S2
113 AG = 0.211 - 0.064 * SS - 0.018 * S2
114 BG = -0.215 + 0.122 * S
116 D = 0.0 + 0.253 * S - 0.081 * S2
117 E = 3.990 + 2.014 * S
118 ES = 1.720 + 0.986 * S
119 S0 = GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
121 C...X * C = X * CBAR :
125 AK = 1.228 - 0.231 * S
126 BK = 3.806 - 0.337 * S2
127 AG = 0.932 + 0.150 * S
130 D = 0.0 + 0.138 * S - 0.028 * S2
131 E = 5.588 + 0.628 * S
132 ES = 2.665 + 1.054 * S
133 C0 = GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
135 C...X * B = X * BBAR :
139 AK = 1.719 - 0.292 * S
140 BK = 0.928 + 0.096 * S
141 AG = 0.845 + 0.178 * S
144 D = -0.191 + 0.151 * S
145 E = 6.089 + 0.282 * S
146 ES = 3.379 + 1.062 * S
147 B0 = GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)