--- /dev/null
+*
+* $Id$
+*
+* $Log$
+* Revision 1.1.1.2 1996/10/30 08:28:40 cernlib
+* Version 7.04
+*
+* Revision 1.1.1.1 1996/04/12 15:29:23 plothow
+* Version 7.01
+*
+*
+#include "pdf/pilot.h"
+ SUBROUTINE GRVGAHO (ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL)
+* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+* *
+* 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 *
+* *
+* FOR A DETAILED EXPLANATION SEE : *
+* M. GLUECK, E.REYA, A.VOGT: DO-TH 91/31 *
+* *
+* THE OUTPUT IS ALWAYS 1./ ALPHA(EM) * X * PARTON DENSITY *
+* output modified by HPB to be always X * PARTON DENSITY *
+* *
+* THE PARAMETRIZATIONS ARE FITTED TO THE PARTON DISTRIBUTIONS *
+* FOR Q ** 2 BETWEEN MU ** 2 (= 0.25 / 0.30 GEV ** 2 IN LO *
+* / HO) AND 1.E6 GEV ** 2 AND FOR X BETWEEN 1.E-5 AND 1. *
+* *
+* HEAVY QUARK THRESHOLDS Q(H) = M(H) : *
+* M(C) = 1.5, M(B) = 4.5, M(T) = 100 GEV *
+* *
+* CORRESPONDING LAMBDA(F) VALUES FOR F ACTIVE FLAVOURS : *
+* LO : LAMBDA(3) = 0.232, LAMBDA(4) = 0.200, *
+* LAMBDA(5) = 0.153, LAMBDA(6) = 0.082 GEV *
+* HO : LAMBDA(3) = 0.248, LAMBDA(4) = 0.200, *
+* LAMBDA(5) = 0.131, LAMBDA(6) = 0.053 GEV *
+* *
+* HO DISTRIBUTIONS REFER TO THE DIS(GAMMA) SCHEME, SEE : *
+* M. GLUECK, E.REYA, A.VOGT: DO-TH 91/26 *
+* *
+* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+C
+ IMPLICIT REAL (A - Y)
+#include "pdf/expdp.inc"
+ + ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL
+ DATA ALPHEM/7.29927D-3/
+ REAL X, Q
+ X = ZX
+ Q = ZQ
+ MU2 = 0.3
+ LAM2 = 0.248 * 0.248
+ Q2 = Q*Q
+ S = ALOG (ALOG(Q2/LAM2) / ALOG(MU2/LAM2))
+ SS = SQRT (S)
+ S2 = S * S
+C...X * U = X * UBAR :
+ AL = 0.583
+ BE = 0.688
+ AK = 0.449 - 0.025 * S - 0.071 * S2
+ BK = 5.060 - 1.116 * SS
+ AG = 0.103
+ BG = 0.319 + 0.422 * S
+ C = 1.508 + 4.792 * S - 1.963 * S2
+ D = 1.075 + 0.222 * SS - 0.193 * S2
+ E = 4.147 + 1.131 * S
+ ES = 1.661 + 0.874 * S
+ UH = GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
+ ZUV = UH * ALPHEM
+ ZUB = ZUV
+C...X * D = X * DBAR :
+ AL = 0.591
+ BE = 0.698
+ AK = 0.442 - 0.132 * S - 0.058 * S2
+ BK = 5.437 - 1.916 * SS
+ AG = 0.099
+ BG = 0.311 - 0.059 * S
+ C = 0.800 + 0.078 * S - 0.100 * S2
+ D = 0.862 + 0.294 * SS - 0.184 * S2
+ E = 4.202 + 1.352 * S
+ ES = 1.841 + 0.990 * S
+ DH = GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
+ ZDV = DH * ALPHEM
+ ZDB = ZDV
+C...X * G :
+ AL = 1.161
+ BE = 1.591
+ AK = 0.530 - 0.742 * SS + 0.025 * S2
+ BK = 5.662
+ AG = 0.533 - 0.281 * SS + 0.218 * S2
+ BG = 0.025 - 0.518 * S + 0.156 * S2
+ C = -0.282 + 0.209 * S2
+ D = 0.107 + 1.058 * S - 0.218 * S2
+ E = 0.0 + 2.704 * S
+ ES = 3.071 - 0.378 * S
+ GH = GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
+ ZGL = GH * ALPHEM
+C...X * S = X * SBAR :
+ SF = 0.0
+ AL = 0.635
+ BE = 0.456
+ AK = 1.770 - 0.735 * SS - 0.079 * S2
+ BK = 3.832
+ AG = 0.084 - 0.023 * S
+ BG = 0.136
+ C = 2.119 - 0.942 * S + 0.063 * S2
+ D = 1.271 + 0.076 * S - 0.190 * S2
+ E = 4.604 + 0.737 * S
+ ES = 1.641 + 0.976 * S
+ SH = GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
+ ZSB = SH * ALPHEM
+C...X * C = X * CBAR :
+ SF = 0.820
+ AL = 0.926
+ BE = 0.152
+ AK = 1.142 - 0.175 * S
+ BK = 3.276
+ AG = 0.504 + 0.317 * S
+ BG = -0.433
+ C = 3.334
+ D = 0.398 + 0.326 * S - 0.107 * S2
+ E = 5.493 + 0.408 * S
+ ES = 2.426 + 1.277 * S
+ CH = GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
+ ZCB = CH * ALPHEM
+C...X * B = X * BBAR :
+ SF = 1.297
+ AL = 0.969
+ BE = 0.266
+ AK = 1.953 - 0.391 * S
+ BK = 1.657 - 0.161 * S
+ AG = 1.076 + 0.034 * S
+ BG = -2.015
+ C = 1.662
+ D = 0.353 + 0.016 * S
+ E = 5.713 + 0.249 * S
+ ES = 3.456 + 0.673 * S
+ BH = GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
+ ZBB = BH * ALPHEM
+c
+ RETURN
+ END