5 * Revision 1.1.1.2 1996/10/30 08:29:48 cernlib
8 * Revision 1.1.1.1 1996/04/12 15:29:35 plothow
12 #include "pdf/pilot.h"
13 C-----------------------------------------------------------------------
14 SUBROUTINE SFGRVL(DX,DSCAL,DUPV,DDNV,DSEA,DSTR,DCHM,DBOT,DTOP,DGL)
16 C :::::::::::: Structure functions from Glueck, Reya and Vogt (LO)
17 C :::::::::::: Lambda(NF=3) = 0.250 GeV
20 #include "pdf/expdp.inc"
21 + DX,DSCAL,DUPV,DDNV,DSEA,DSTR,DCHM,DBOT,DTOP,DGL
22 PARAMETER (ALAM=0.250)
27 C generate the individual structure fcn calls
29 C...Lowest order parametrization of Gluck, Reya, Vogt.
30 C...Allowed variable range: 0.2 GeV^2 < Q2 < 1E6 GeV^2; 1E-4 < x < 1;
31 C...extended to 0.2 GeV^2 < Q2 < 1E8 GeV^2; 1E-6 < x < 1
32 C...after consultation with the authors.
34 C...Determine s and x.
35 Q2IN=MIN(1E8,MAX(0.2,Q2))
36 SD=LOG(LOG(Q2IN/ALAM**2)/LOG(0.2/ALAM**2))
40 C...Calculate structure functions.
41 XQ(1)=(0.794+0.312*SD)*XC**(0.427-0.011*SD)*
42 & (1.+(6.887-2.227*SD)*XC+(-11.083+2.136*SD)*XC**2+
43 & (3.900+1.079*SD)*XC**3)*(1.-XC)**(1.037+1.077*SD)
44 XQ(2)=(0.486+0.139*SD)*XC**(0.434-0.018*SD)*
45 & (1.+(7.716-2.684*SD)*XC+(-12.768+3.122*SD)*XC**2+
46 & (4.564+0.470*SD)*XC**3)*(1.-XC)**(1.889+1.129*SD)
47 XQ(3)=(XC**(0.415+0.186*SD)*((0.786+0.942*SD)+
48 & (5.256-5.810*SD)*XC+(-4.599+5.842*SD)*XC**2)+SD**0.592*
49 & EXP(-(0.398+2.135*SD)+SQRT(3.779*SD**1.250*XL)))*
50 & (1.-XC)**(1.622+1.980*SD)
51 XQ(4)=SD**0.448*(1.-XC)**(5.540-0.445*SD)*
52 & EXP(-(4.668+1.230*SD)+SQRT((13.173-1.361*SD)*SD**0.442*XL))/
53 & XL**(3.181-0.862*SD)
55 IF(SD.GT.1.125) XQ(5)=(SD-1.125)*(1.-XC)**(2.038+1.022*SD)*
56 & EXP(-(4.290+1.569*SD)+SQRT((2.982+1.452*SD)*SD**0.5*XL))
58 IF(SD.GT.1.603) XQ(6)=(SD-1.603)*(1.-XC)**(2.230+1.052*SD)*
59 & EXP(-(4.566+1.559*SD)+SQRT((4.147+1.268*SD)*SD**0.5*XL))
61 C...Put into output array - special factor for small x.
63 C IF(X.LT.1E-4.AND.ABS(XLOWPW-1.).GT.0.01)
64 C & CXS=(1E-4/X)**(XLOWPW-1.)