LHAPDF/lhapdf5.3.1/wrapgrvg.f

   1       subroutine GRVGevolvep0(xin,qin,p2in,ip2in,pdf)
   2       include 'parmsetup.inc'
   3       real*8 xin,qin,q2in,p2in,pdf(-6:6),xval(45),qcdl4,qcdl5
   4       real*8 upv,dnv,usea,dsea,str,chm,bot,top,glu,zbot,zchm
   5       character*16 name(nmxset)
   6       integer nmem(nmxset),ndef(nmxset),mmem
   7       common/NAME/name,nmem,ndef,mmem
   8       integer nset
   9
  10       save
  11
  12       call getnset(iset)
  13       call getnmem(iset,imem)
  14       if(imem.eq.1) then
  15         call GRVGALO (xin,qin,upv,dnv,usea,dsea,str,chm,bot,glu)
  16       elseif(imem.eq.2.or.imem.eq.0) then
  17         q2in = qin*qin
  18 c calls GRVGALO for charm and bottom, rest from GRSGALO
  19         call GRVGALO(xin,qin,upv,dnv,usea,dsea,str,chm,bot,glu)
  20         call GRSGALO(xin,q2in,p2in,
  21      +               upv,dnv,usea,dsea,str,zchm,zbot,glu)
  22       else
  23         CONTINUE
  24       endif
  25       pdf(-6)= 0.0d0
  26       pdf(6)= 0.0d0
  27       pdf(-5)= bot
  28       pdf(5 )= bot
  29       pdf(-4)= chm
  30       pdf(4 )= chm
  31       pdf(-3)= str
  32       pdf(3 )= str
  33       pdf(-2)= usea
  34       pdf(2 )= upv
  35       pdf(-1)= dsea
  36       pdf(1 )= dnv
  37       pdf(0 )= glu
  38
  39       return
  40 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
  41       entry GRVGevolvep1(xin,qin,p2in,ip2in,pdf)
  42
  43       if(imem.eq.1) then
  44         call GRVGAH0 (xin,qin,upv,dnv,usea,dsea,str,chm,bot,glu)
  45       elseif(imem.eq.2 .or. imem.eq.0) then
  46         call GRVGAHO (xin,qin,upv,dnv,usea,dsea,str,chm,bot,glu)
  47       else
  48         CONTINUE
  49       endif
  50
  51       pdf(-6)= 0.0d0
  52       pdf(6)= 0.0d0
  53       pdf(-5)= bot
  54       pdf(5 )= bot
  55       pdf(-4)= chm
  56       pdf(4 )= chm
  57       pdf(-3)= str
  58       pdf(3 )= str
  59       pdf(-2)= usea
  60       pdf(2 )= upv
  61       pdf(-1)= dsea
  62       pdf(1 )= dnv
  63       pdf(0 )= glu
  64
  65       return
  66 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
  67       entry GRVGread(nset)
  68       read(1,*)nmem(nset),ndef(nset)
  69       return
  70 c
  71 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
  72       entry GRVGalfa(alfas,qalfa)
  73         call getnset(iset)
  74         call GetOrderAsM(iset,iord)
  75         call Getlam4M(iset,imem,qcdl4)
  76         call Getlam5M(iset,imem,qcdl5)
  77         call aspdflib(alfas,Qalfa,iord,qcdl5)
  78       return
  79 c
  80 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
  81       entry GRVGinit(Eorder,Q2fit)
  82       return
  83 c
  84 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
  85       entry GRVGpdf(mem)
  86       call getnset(iset)
  87       call setnmem(iset,mem)
  88
  89 c      imem = mem
  90       return
  91 c
  92  1000 format(5e13.5)
  93       end
  94 c
  95        SUBROUTINE GRVGAH0 (ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL)
  96 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
  97 *                                                                 *
  98 *      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      *
  99 *                                                                 *
 100 *                 FOR A DETAILED EXPLANATION SEE :                *
 101 *              M. GLUECK, E.REYA, A.VOGT: DO-TH 91/31             *
 102 *                                                                 *
 103 *    THE OUTPUT IS ALWAYS   1./ ALPHA(EM) * X * PARTON DENSITY    *
 104 *    output modified by HPB to be always    X * PARTON DENSITY    *
 105 *                                                                 *
 106 *   THE PARAMETRIZATIONS ARE FITTED TO THE PARTON DISTRIBUTIONS   *
 107 *   FOR Q ** 2 BETWEEN MU ** 2 (=  0.25 / 0.30  GEV ** 2  IN LO   *
 108 *   / HO) AND  1.E6 GEV ** 2  AND FOR X BETWEEN  1.E-5  AND  1.   *
 109 *                                                                 *
 110 *              HEAVY QUARK THRESHOLDS  Q(H) = M(H) :              *
 111 *         M(C)  =  1.5,  M(B)  =  4.5,  M(T)  =  100  GEV         *
 112 *                                                                 *
 113 *      CORRESPONDING LAMBDA(F) VALUES FOR F ACTIVE FLAVOURS :     *
 114 *      LO :   LAMBDA(3)  =  0.232,   LAMBDA(4)  =  0.200,         *
 115 *             LAMBDA(5)  =  0.153,   LAMBDA(6)  =  0.082  GEV     *
 116 *      HO :   LAMBDA(3)  =  0.248,   LAMBDA(4)  =  0.200,         *
 117 *             LAMBDA(5)  =  0.131,   LAMBDA(6)  =  0.053  GEV     *
 118 *                                                                 *
 119 *      HO DISTRIBUTIONS REFER TO THE DIS(GAMMA) SCHEME, SEE :     *
 120 *              M. GLUECK, E.REYA, A.VOGT: DO-TH 91/26             *
 121 *                                                                 *
 122 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 123 C
 124        IMPLICIT REAL (A - Y)
 125        double precision
 126      +        ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL
 127        REAL  X, Q
 128        DATA ALPHEM/7.29927D-3/
 129        X = ZX
 130        Q = ZQ
 131        MU2  = 0.3
 132        LAM2 = 0.248 * 0.248
 133        Q2 = Q*Q
 134        S  = ALOG (ALOG(Q2/LAM2) / ALOG(MU2/LAM2))
 135        SS = SQRT (S)
 136        S2 = S * S
 137 C...X * U = X * UBAR :
 138        AL =  1.447
 139        BE =  0.848
 140        AK =  0.527 + 0.200 * S  - 0.107 * S2
 141        BK =  7.106 - 0.310 * SS - 0.786 * S2
 142        AG =  0.197 + 0.533 * S
 143        BG =  0.062 - 0.398 * S  + 0.109 * S2
 144        C  =          0.755 * S  - 0.112 * S2
 145        D  =  0.318 - 0.059 * S
 146        E  =  4.225 + 1.708 * S
 147        ES =  1.752 + 0.866 * S
 148        U0 =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 149        ZUV = U0 * ALPHEM
 150        ZUB = ZUV
 151 C...X * D = X * DBAR :
 152        AL =  1.424
 153        BE =  0.770
 154        AK =  0.500 + 0.067 * SS - 0.055 * S2
 155        BK =  0.376 - 0.453 * SS + 0.405 * S2
 156        AG =  0.156 + 0.184 * S
 157        BG =   0.0  - 0.528 * S  + 0.146 * S2
 158        C  =  0.121 + 0.092 * S
 159        D  =  0.379 - 0.301 * S  + 0.081 * S2
 160        E  =  4.346 + 1.638 * S
 161        ES =  1.645 + 1.016 * S
 162        D0  =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 163        ZDV = D0 * ALPHEM
 164        ZDB = ZDV
 165 C...X * G :
 166        AL =  0.661
 167        BE =  0.793
 168        AK =  0.537 - 0.600 * SS
 169        BK =  6.389              - 0.953 * S2
 170        AG =  0.558 - 0.383 * SS + 0.261 * S2
 171        BG =   0.0  - 0.305 * S
 172        C  = -0.222              + 0.078 * S2
 173        D  =  0.153 + 0.978 * S  - 0.209 * S2
 174        E  =  1.429 + 1.772 * S
 175        ES =  3.331 + 0.806 * S
 176        G0 =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 177        ZGL = G0 * ALPHEM
 178 C...X * S = X * SBAR :
 179        SF =   0.0
 180        AL =  1.578
 181        BE =  0.863
 182        AK =  0.622 + 0.332 * S  - 0.300 * S2
 183        BK =  2.469
 184        AG =  0.211 - 0.064 * SS - 0.018 * S2
 185        BG = -0.215 + 0.122 * S
 186        C  =  0.153
 187        D  =   0.0  + 0.253 * S  - 0.081 * S2
 188        E  =  3.990 + 2.014 * S
 189        ES =  1.720 + 0.986 * S
 190        S0 =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 191        ZSB = S0 * ALPHEM
 192 C...X * C = X * CBAR :
 193        SF =  0.820
 194        AL =  0.929
 195        BE =  0.381
 196        AK =  1.228 - 0.231 * S
 197        BK =  3.806             - 0.337 * S2
 198        AG =  0.932 + 0.150 * S
 199        BG = -0.906
 200        C  =  1.133
 201        D  =   0.0  + 0.138 * S  - 0.028 * S2
 202        E  =  5.588 + 0.628 * S
 203        ES =  2.665 + 1.054 * S
 204        C0 =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 205        ZCB = C0 * ALPHEM
 206 C...X * B = X * BBAR :
 207        SF =  1.297
 208        AL =  0.970
 209        BE =  0.207
 210        AK =  1.719 - 0.292 * S
 211        BK =  0.928 + 0.096 * S
 212        AG =  0.845 + 0.178 * S
 213        BG = -2.310
 214        C  =  1.558
 215        D  = -0.191 + 0.151 * S
 216        E  =  6.089 + 0.282 * S
 217        ES =  3.379 + 1.062 * S
 218        B0 =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 219        ZBB = B0 * ALPHEM
 220 C
 221        RETURN
 222        END
 223 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
 224        SUBROUTINE GRVGAHO (ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL)
 225 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 226 *                                                                 *
 227 *      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      *
 228 *                                                                 *
 229 *                 FOR A DETAILED EXPLANATION SEE :                *
 230 *              M. GLUECK, E.REYA, A.VOGT: DO-TH 91/31             *
 231 *                                                                 *
 232 *    THE OUTPUT IS ALWAYS   1./ ALPHA(EM) * X * PARTON DENSITY    *
 233 *    output modified by HPB to be always    X * PARTON DENSITY    *
 234 *                                                                 *
 235 *   THE PARAMETRIZATIONS ARE FITTED TO THE PARTON DISTRIBUTIONS   *
 236 *   FOR Q ** 2 BETWEEN MU ** 2 (=  0.25 / 0.30  GEV ** 2  IN LO   *
 237 *   / HO) AND  1.E6 GEV ** 2  AND FOR X BETWEEN  1.E-5  AND  1.   *
 238 *                                                                 *
 239 *              HEAVY QUARK THRESHOLDS  Q(H) = M(H) :              *
 240 *         M(C)  =  1.5,  M(B)  =  4.5,  M(T)  =  100  GEV         *
 241 *                                                                 *
 242 *      CORRESPONDING LAMBDA(F) VALUES FOR F ACTIVE FLAVOURS :     *
 243 *      LO :   LAMBDA(3)  =  0.232,   LAMBDA(4)  =  0.200,         *
 244 *             LAMBDA(5)  =  0.153,   LAMBDA(6)  =  0.082  GEV     *
 245 *      HO :   LAMBDA(3)  =  0.248,   LAMBDA(4)  =  0.200,         *
 246 *             LAMBDA(5)  =  0.131,   LAMBDA(6)  =  0.053  GEV     *
 247 *                                                                 *
 248 *      HO DISTRIBUTIONS REFER TO THE DIS(GAMMA) SCHEME, SEE :     *
 249 *              M. GLUECK, E.REYA, A.VOGT: DO-TH 91/26             *
 250 *                                                                 *
 251 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 252 C
 253        IMPLICIT REAL (A - Y)
 254        double precision
 255      +        ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL
 256        DATA ALPHEM/7.29927D-3/
 257        REAL  X, Q
 258        X = ZX
 259        Q = ZQ
 260        MU2  = 0.3
 261        LAM2 = 0.248 * 0.248
 262        Q2 = Q*Q
 263        S  = ALOG (ALOG(Q2/LAM2) / ALOG(MU2/LAM2))
 264        SS = SQRT (S)
 265        S2 = S * S
 266 C...X * U = X * UBAR :
 267        AL =  0.583
 268        BE =  0.688
 269        AK =  0.449 - 0.025 * S  - 0.071 * S2
 270        BK =  5.060 - 1.116 * SS
 271        AG =  0.103
 272        BG =  0.319 + 0.422 * S
 273        C  =  1.508 + 4.792 * S  - 1.963 * S2
 274        D  =  1.075 + 0.222 * SS - 0.193 * S2
 275        E  =  4.147 + 1.131 * S
 276        ES =  1.661 + 0.874 * S
 277        UH =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 278        ZUV = UH * ALPHEM
 279        ZUB = ZUV
 280 C...X * D = X * DBAR :
 281        AL =  0.591
 282        BE =  0.698
 283        AK =  0.442 - 0.132 * S  - 0.058 * S2
 284        BK =  5.437 - 1.916 * SS
 285        AG =  0.099
 286        BG =  0.311 - 0.059 * S
 287        C  =  0.800 + 0.078 * S  - 0.100 * S2
 288        D  =  0.862 + 0.294 * SS - 0.184 * S2
 289        E  =  4.202 + 1.352 * S
 290        ES =  1.841 + 0.990 * S
 291        DH  =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 292        ZDV = DH * ALPHEM
 293        ZDB = ZDV
 294 C...X * G :
 295        AL =  1.161
 296        BE =  1.591
 297        AK =  0.530 - 0.742 * SS + 0.025 * S2
 298        BK =  5.662
 299        AG =  0.533 - 0.281 * SS + 0.218 * S2
 300        BG =  0.025 - 0.518 * S  + 0.156 * S2
 301        C  = -0.282              + 0.209 * S2
 302        D  =  0.107 + 1.058 * S  - 0.218 * S2
 303        E  =   0.0  + 2.704 * S
 304        ES =  3.071 - 0.378 * S
 305        GH =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 306        ZGL = GH * ALPHEM
 307 C...X * S = X * SBAR :
 308        SF =   0.0
 309        AL =  0.635
 310        BE =  0.456
 311        AK =  1.770 - 0.735 * SS - 0.079 * S2
 312        BK =  3.832
 313        AG =  0.084 - 0.023 * S
 314        BG =  0.136
 315        C  =  2.119 - 0.942 * S  + 0.063 * S2
 316        D  =  1.271 + 0.076 * S  - 0.190 * S2
 317        E  =  4.604 + 0.737 * S
 318        ES =  1.641 + 0.976 * S
 319        SH =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 320        ZSB = SH * ALPHEM
 321 C...X * C = X * CBAR :
 322        SF =  0.820
 323        AL =  0.926
 324        BE =  0.152
 325        AK =  1.142 - 0.175 * S
 326        BK =  3.276
 327        AG =  0.504 + 0.317 * S
 328        BG = -0.433
 329        C  =  3.334
 330        D  =  0.398 + 0.326 * S  - 0.107 * S2
 331        E  =  5.493 + 0.408 * S
 332        ES =  2.426 + 1.277 * S
 333        CH =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 334        ZCB = CH * ALPHEM
 335 C...X * B = X * BBAR :
 336        SF =  1.297
 337        AL =  0.969
 338        BE =  0.266
 339        AK =  1.953 - 0.391 * S
 340        BK =  1.657 - 0.161 * S
 341        AG =  1.076 + 0.034 * S
 342        BG = -2.015
 343        C  =  1.662
 344        D  =  0.353 + 0.016 * S
 345        E  =  5.713 + 0.249 * S
 346        ES =  3.456 + 0.673 * S
 347        BH =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 348        ZBB = BH * ALPHEM
 349 c
 350        RETURN
 351        END
 352 cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
 353        SUBROUTINE GRVGALO (ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL)
 354 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 355 *                                                                 *
 356 *      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      *
 357 *                                                                 *
 358 *                 FOR A DETAILED EXPLANATION SEE :                *
 359 *              M. GLUECK, E.REYA, A.VOGT: DO-TH 91/31             *
 360 *                                                                 *
 361 *    THE OUTPUT IS ALWAYS   1./ ALPHA(EM) * X * PARTON DENSITY    *
 362 *    output modified by HPB to be always    X * PARTON DENSITY    *
 363 *                                                                 *
 364 *   THE PARAMETRIZATIONS ARE FITTED TO THE PARTON DISTRIBUTIONS   *
 365 *   FOR Q ** 2 BETWEEN MU ** 2 (=  0.25 / 0.30  GEV ** 2  IN LO   *
 366 *   / HO) AND  1.E6 GEV ** 2  AND FOR X BETWEEN  1.E-5  AND  1.   *
 367 *                                                                 *
 368 *              HEAVY QUARK THRESHOLDS  Q(H) = M(H) :              *
 369 *         M(C)  =  1.5,  M(B)  =  4.5,  M(T)  =  100  GEV         *
 370 *                                                                 *
 371 *      CORRESPONDING LAMBDA(F) VALUES FOR F ACTIVE FLAVOURS :     *
 372 *      LO :   LAMBDA(3)  =  0.232,   LAMBDA(4)  =  0.200,         *
 373 *             LAMBDA(5)  =  0.153,   LAMBDA(6)  =  0.082  GEV     *
 374 *      HO :   LAMBDA(3)  =  0.248,   LAMBDA(4)  =  0.200,         *
 375 *             LAMBDA(5)  =  0.131,   LAMBDA(6)  =  0.053  GEV     *
 376 *                                                                 *
 377 *      HO DISTRIBUTIONS REFER TO THE DIS(GAMMA) SCHEME, SEE :     *
 378 *              M. GLUECK, E.REYA, A.VOGT: DO-TH 91/26             *
 379 *                                                                 *
 380 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 381 C
 382        IMPLICIT REAL (A - Y)
 383        double precision
 384      +        ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL
 385        REAL  X, Q
 386        DATA ALPHEM/7.29927D-3/
 387        X = ZX
 388        Q = ZQ
 389        MU2  = 0.25
 390        LAM2 = 0.232 * 0.232
 391        Q2 = Q*Q
 392        S  = ALOG (ALOG(Q2/LAM2) / ALOG(MU2/LAM2))
 393        SS = SQRT (S)
 394        S2 = S * S
 395 C...X * U = X * UBAR :
 396        AL =  1.717
 397        BE =  0.641
 398        AK =  0.500 - 0.176 * S
 399        BK = 15.00  - 5.687 * SS - 0.552 * S2
 400        AG =  0.235 + 0.046 * SS
 401        BG =  0.082 - 0.051 * S  + 0.168 * S2
 402        C  =   0.0  + 0.459 * S
 403        D  =  0.354 - 0.061 * S
 404        E  =  4.899 + 1.678 * S
 405        ES =  2.046 + 1.389 * S
 406        UL =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 407        ZUV = UL * ALPHEM
 408        ZUB = ZUV
 409 C...X * D = X * DBAR :
 410        AL =  1.549
 411        BE =  0.782
 412        AK =  0.496 + 0.026 * S
 413        BK =  0.685 - 0.580 * SS + 0.608 * S2
 414        AG =  0.233 + 0.302 * S
 415        BG =   0.0  - 0.818 * S  + 0.198 * S2
 416        C  =  0.114 + 0.154 * S
 417        D  =  0.405 - 0.195 * S  + 0.046 * S2
 418        E  =  4.807 + 1.226 * S
 419        ES =  2.166 + 0.664 * S
 420        DL  =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 421        ZDV = DL * ALPHEM
 422        ZDB = ZDV
 423 C...X * G :
 424        AL =  0.676
 425        BE =  1.089
 426        AK =  0.462 - 0.524 * SS
 427        BK =  5.451              - 0.804 * S2
 428        AG =  0.535 - 0.504 * SS + 0.288 * S2
 429        BG =  0.364 - 0.520 * S
 430        C  = -0.323              + 0.115 * S2
 431        D  =  0.233 + 0.790 * S  - 0.139 * S2
 432        E  =  0.893 + 1.968 * S
 433        ES =  3.432 + 0.392 * S
 434        GL =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 435        ZGL = GL * ALPHEM
 436 C...X * S = X * SBAR :
 437        SF =   0.0
 438        AL =  1.609
 439        BE =  0.962
 440        AK =  0.470              - 0.099 * S2
 441        BK =  3.246
 442        AG =  0.121 - 0.068 * SS
 443        BG = -0.090 + 0.074 * S
 444        C  =  0.062 + 0.034 * S
 445        D  =   0.0  + 0.226 * S  - 0.060 * S2
 446        E  =  4.288 + 1.707 * S
 447        ES =  2.122 + 0.656 * S
 448        SL =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 449        ZSB = SL * ALPHEM
 450 C...X * C = X * CBAR :
 451        SF =  0.888
 452        AL =  0.970
 453        BE =  0.545
 454        AK =  1.254 - 0.251 * S
 455        BK =  3.932              - 0.327 * S2
 456        AG =  0.658 + 0.202 * S
 457        BG = -0.699
 458        C  =  0.965
 459        D  =   0.0  + 0.141 * S  - 0.027 * S2
 460        E  =  4.911 + 0.969 * S
 461        ES =  2.796 + 0.952 * S
 462        CL =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 463        ZCB = CL * ALPHEM
 464 C...X * B = X * BBAR :
 465        SF =  1.351
 466        AL =  1.016
 467        BE =  0.338
 468        AK =  1.961 - 0.370 * S
 469        BK =  0.923 + 0.119 * S
 470        AG =  0.815 + 0.207 * S
 471        BG = -2.275
 472        C  =  1.480
 473        D  = -0.223 + 0.173 * S
 474        E  =  5.426 + 0.623 * S
 475        ES =  3.819 + 0.901 * S
 476        BL =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 477        ZBB = BL * ALPHEM
 478 C
 479        RETURN
 480        END
 481 cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
 482 C-----------------------------------------------------------------------
 483 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 484 *                                                                 *
 485 *           G R S - LO - VIRTUAL PHOTON PARAMETRIZATIONS          *
 486 *                                                                 *
 487 *                 FOR A DETAILED EXPLANATION SEE                  *
 488 *                M. GLUECK, E.REYA, M. STRATMANN :                *
 489 *                    PHYS. REV. D51 (1995) 3220                   *
 490 *                                                                 *
 491 *   THE PARAMETRIZATIONS ARE FITTED TO THE EVOLVED PARTONS FOR    *
 492 *        Q**2 / GEV**2  BETWEEN   0.6   AND  5.E4                 *
 493 *                       AND (!)  Q**2 > 5 P**2                    *
 494 *        P**2 / GEV**2  BETWEEN   0.0   AND  10.                  *
 495 *                       P**2 = 0  <=> REAL PHOTON                 *
 496 *             X         BETWEEN  1.E-4  AND   1.                  *
 497 *                                                                 *
 498 *   HEAVY QUARK THRESHOLDS  Q(H) = M(H)  IN THE BETA FUNCTION :   *
 499 *                   M(C)  =  1.5,  M(B)  =  4.5                   *
 500 *   CORRESPONDING LAMBDA(F) VALUES IN GEV FOR  Q**2 > M(H)**2 :   *
 501 *      LO :   LAMBDA(3)  =  0.232,   LAMBDA(4)  =  0.200,         *
 502 *             LAMBDA(5)  =  0.153,                                *
 503 *   THE NUMBER OF ACTIVE QUARK FLAVOURS IS  NF = 3  EVERYWHERE    *
 504 *   EXCEPT IN THE BETA FUNCTION, I.E. THE HEAVY QUARKS C,B,...    *
 505 *   ARE NOT PRESENT AS PARTONS IN THE Q2-EVOLUTION.               *
 506 *                                                                 *
 507 *   PLEASE REPORT ANY STRANGE BEHAVIOUR TO :                      *
 508 *          STRAT@HAL1.PHYSIK.UNI-DORTMUND.DE                      *
 509 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 510 *
 511 *...INPUT PARAMETERS :
 512 *
 513 *    X   = MOMENTUM FRACTION
 514 *    Q2  = SCALE Q**2 IN GEV**2
 515 *    P2  = VIRTUALITY OF THE PHOTON IN GEV**2
 516 *
 517 *...OUTPUT (ALWAYS X TIMES THE DISTRIBUTION DIVIDED BY ALPHA_EM) :
 518 *...OUTPUT (ALWAYS X TIMES THE DISTRIBUTION) :  modified H.P.-B. 10.9.1996
 519 *
 520 ********************************************************
 521       SUBROUTINE GRSGALO(DX,DQ2,DP2,
 522      +                     DUPV,DDNV,DUSEA,DDSEA,DSTR,DCHM,DBOT,DGL)
 523 C      subroutine grsgalo(x,q2,p2,ugam,dgam,sgam,ggam)
 524       implicit real*8 (a-h,o-z)
 525       double precision
 526      +          x, q2, p2, mu2, lam2,
 527      +          ugam, dgam, sgam, ggam,
 528      +          DUPV,DDNV,DUSEA,DDSEA,DSTR,DCHM,DBOT,DGL
 529 C
 530       dimension u1(40),ds1(40),g1(40)
 531       dimension ud2(20),s2(20),g2(20)
 532       dimension up0(20),dsp0(20),gp0(20)
 533       DATA ALPHEM/7.29927D-3/
 534 c
 535       data u1/-0.139d0,0.783d0,0.132d0,0.087d0,0.003d0,-0.0134d0,
 536      +   0.009d0,-0.017d0,0.092d0,-0.516d0,-0.085d0,0.439d0,
 537      +   0.013d0,0.108d0,-0.019d0,-0.272d0,-0.167d0,0.138d0,
 538      +   0.076d0,0.026d0,-0.013d0,0.27d0,0.107d0,-0.097d0,0.04d0,
 539      +   0.064d0,0.011d0,0.002d0,0.057d0,-0.057d0,0.162d0,
 540      +   -0.172d0,0.124d0,-0.016d0,-0.065d0,0.044d0,-1.009d0,
 541      +   0.622d0,0.227d0,-0.184d0/
 542       data ds1/0.033d0,0.007d0,-0.0516d0,0.12d0,0.001d0,-0.013d0,
 543      +   0.018d0,-0.028d0,0.102d0,-0.595d0,-0.114d0,0.669d0,
 544      +   0.022d0,0.001d0,-0.003d0,-0.0583d0,-0.041d0,0.035d0,
 545      +   0.009d0,0.009d0,0.004d0,0.054d0,0.025d0,-0.02d0,
 546      +   0.007d0,0.021d0,0.01d0,0.004d0,-0.067d0,0.06d0,-0.148d0,
 547      +   0.13d0,0.032d0,-0.009d0,-0.06d0,0.036d0,-0.39d0,0.033d0,
 548      +   0.245d0,-0.171d0/
 549       data g1/0.025d0,0.d0,-0.018d0,0.112d0,-0.025d0,0.177d0,
 550      +   -0.022d0,0.024d0,0.001d0,-0.0104d0,0.d0,0.d0,-1.082d0,
 551      +   -1.666d0,0.d0,0.086d0,0.d0,0.053d0,0.005d0,-0.058d0,
 552      +   0.034d0,0.073d0,1.08d0,1.63d0,-0.0256d0,-0.088d0,0.d0,
 553      +   0.d0,-0.004d0,0.016d0,0.007d0,-0.012d0,0.01d0,-0.673d0,
 554      +   0.126d0,-0.167d0,0.032d0,-0.227d0,0.086d0,-0.159d0/
 555       data ud2/0.756d0,0.187d0,0.109d0,-0.163d0,0.002d0,0.004d0,
 556      +   0.054d0,-0.039d0,22.53d0,-21.02d0,5.608d0,0.332d0,
 557      +   -0.008d0,-0.021d0,0.381d0,0.572d0,4.774d0,1.436d0,
 558      +   -0.614d0,3.548d0/
 559       data s2/0.902d0,0.182d0,0.271d0,-0.346d0,0.017d0,-0.01d0,
 560      +   -0.011d0,0.0065d0,17.1d0,-13.29d0,6.519d0,0.031d0,
 561      +   -0.0176d0,0.003d0,1.243d0,0.804d0,4.709d0,1.499d0,
 562      +   -0.48d0,3.401d0/
 563       data g2/0.364d0,1.31d0,0.86d0,-0.254d0,0.611d0,0.008d0,
 564      +   -0.097d0,-2.412d0,-0.843d0,2.248d0,-0.201d0,1.33d0,
 565      +   0.572d0,0.44d0,1.233d0,0.009d0,0.954d0,1.862d0,3.791d0,
 566      +   -0.079d0/
 567       data up0/1.551d0,0.105d0,1.089d0,-0.172d0,3.822d0,-2.162d0,
 568      +   0.533d0,-0.467d0,-0.412d0,0.2d0,0.377d0,0.299d0,0.487d0,
 569      +   0.0766d0,0.119d0,0.063d0,7.605d0,0.234d0,-0.567d0,
 570      +   2.294d0/
 571       data dsp0/2.484d0,1.214d0,1.088d0,-0.1735d0,4.293d0,
 572      +   -2.802d0,0.5975d0,-0.1193d0,-0.0872d0,0.0418d0,0.128d0,
 573      +   0.0337d0,0.127d0,0.0135d0,0.14d0,0.0423d0,6.946d0,
 574      +   0.814d0,1.531d0,0.124d0/
 575       data gp0/1.682d0,1.1d0,0.5888d0,-0.4714d0,0.5362d0,0.0127d0,
 576      +   -2.438d0,0.03399d0,0.07825d0,0.05842d0,0.08393d0,2.348d0,
 577      +   -0.07182d0,1.084d0,0.3098d0,-0.07514d0,3.327d0,1.1d0,
 578      +   2.264d0,0.2675d0/
 579 c
 580       save u1,ds1,g1,ud2,s2,g2,up0,dsp0,gp0
 581 c
 582       x  = DX
 583       q  = SQRT(DQ2)
 584       q2 = DQ2
 585       p2 = DP2
 586       mu2=0.25d0
 587       lam2=0.232d0*0.232d0
 588 c
 589       if(p2.le.0.25d0) then
 590          s=log(log(q2/lam2)/log(mu2/lam2))
 591          lp1=0.d0
 592          lp2=0.d0
 593       else
 594          if(q2.lt.p2) then
 595             write(*,1000)
 596  1000       format
 597      +      ('  WARNING: GRSGALO has been called with Q2 < P2 !',/,
 598      +       '           GRSGALO is about to blow up, therefore',/,
 599      +       '           Q2 is set equal to P2')
 600             q2=p2
 601          endif
 602          s=log(log(q2/lam2)/log(p2/lam2))
 603          lp1=log(p2/mu2)*log(p2/mu2)
 604          lp2=log(p2/mu2+log(p2/mu2))
 605       endif
 606 c
 607       alp=up0(1)+lp1*u1(1)+lp2*u1(2)
 608       bet=up0(2)+lp1*u1(3)+lp2*u1(4)
 609       a=up0(3)+lp1*u1(5)+lp2*u1(6)+
 610      +  (up0(4)+lp1*u1(7)+lp2*u1(8))*s
 611       b=up0(5)+lp1*u1(9)+lp2*u1(10)+
 612      +  (up0(6)+lp1*u1(11)+lp2*u1(12))*s**0.5+
 613      +  (up0(7)+lp1*u1(13)+lp2*u1(14))*s**2
 614       gb=up0(8)+lp1*u1(15)+lp2*u1(16)+
 615      +  (up0(9)+lp1*u1(17)+lp2*u1(18))*s+
 616      +  (up0(10)+lp1*u1(19)+lp2*u1(20))*s**2
 617       ga=up0(11)+lp1*u1(21)+lp2*u1(22)+
 618      +  (up0(12)+lp1*u1(23)+lp2*u1(24))*s**0.5
 619       gc=up0(13)+lp1*u1(25)+lp2*u1(33)+
 620      +  (up0(14)+lp1*u1(26)+lp2*u1(34))*s
 621       gd=up0(15)+lp1*u1(27)+lp2*u1(35)+
 622      +  (up0(16)+lp1*u1(28)+lp2*u1(36))*s
 623       ge=up0(17)+lp1*u1(29)+lp2*u1(37)+
 624      +  (up0(18)+lp1*u1(30)+lp2*u1(38))*s
 625       gep=up0(19)+lp1*u1(31)+lp2*u1(39)+
 626      +  (up0(20)+lp1*u1(32)+lp2*u1(40))*s
 627       upart1=grsf2(x,s,alp,bet,a,b,ga,gb,gc,gd,ge,gep)
 628 c
 629       alp=dsp0(1)+lp1*ds1(1)+lp2*ds1(2)
 630       bet=dsp0(2)+lp1*ds1(3)+lp2*ds1(4)
 631       a=dsp0(3)+lp1*ds1(5)+lp2*ds1(6)+
 632      +  (dsp0(4)+lp1*ds1(7)+lp2*ds1(8))*s
 633       b=dsp0(5)+lp1*ds1(9)+lp2*ds1(10)+
 634      +  (dsp0(6)+lp1*ds1(11)+lp2*ds1(12))*s**0.5+
 635      +  (dsp0(7)+lp1*ds1(13)+lp2*ds1(14))*s**2
 636       gb=dsp0(8)+lp1*ds1(15)+lp2*ds1(16)+
 637      +  (dsp0(9)+lp1*ds1(17)+lp2*ds1(18))*s+
 638      +  (dsp0(10)+lp1*ds1(19)+lp2*ds1(20))*s**2
 639       ga=dsp0(11)+lp1*ds1(21)+lp2*ds1(22)+
 640      +  (dsp0(12)+lp1*ds1(23)+lp2*ds1(24))*s
 641       gc=dsp0(13)+lp1*ds1(25)+lp2*ds1(33)+
 642      +  (dsp0(14)+lp1*ds1(26)+lp2*ds1(34))*s
 643       gd=dsp0(15)+lp1*ds1(27)+lp2*ds1(35)+
 644      +  (dsp0(16)+lp1*ds1(28)+lp2*ds1(36))*s
 645       ge=dsp0(17)+lp1*ds1(29)+lp2*ds1(37)+
 646      +  (dsp0(18)+lp1*ds1(30)+lp2*ds1(38))*s
 647       gep=dsp0(19)+lp1*ds1(31)+lp2*ds1(39)+
 648      +  (dsp0(20)+lp1*ds1(32)+lp2*ds1(40))*s
 649       dspart1=grsf2(x,s,alp,bet,a,b,ga,gb,gc,gd,ge,gep)
 650 c
 651       alp=gp0(1)+lp1*g1(1)+lp2*g1(2)
 652       bet=gp0(2)+lp1*g1(3)+lp2*g1(4)
 653       a=gp0(3)+lp1*g1(5)+lp2*g1(6)+
 654      +  (gp0(4)+lp1*g1(7)+lp2*g1(8))*s**0.5
 655       b=gp0(5)+lp1*g1(9)+lp2*g1(10)+
 656      +  (gp0(6)+lp1*g1(11)+lp2*g1(12))*s**2
 657       gb=gp0(7)+lp1*g1(13)+lp2*g1(14)+
 658      +  (gp0(8)+lp1*g1(15)+lp2*g1(16))*s
 659       ga=gp0(9)+lp1*g1(17)+lp2*g1(18)+
 660      +  (gp0(10)+lp1*g1(19)+lp2*g1(20))*s**0.5+
 661      +  (gp0(11)+lp1*g1(21)+lp2*g1(22))*s**2
 662       gc=gp0(12)+lp1*g1(23)+lp2*g1(24)+
 663      +  (gp0(13)+lp1*g1(25)+lp2*g1(26))*s**2
 664       gd=gp0(14)+lp1*g1(27)+lp2*g1(28)+
 665      +  (gp0(15)+lp1*g1(29)+lp2*g1(30))*s+
 666      +  (gp0(16)+lp1*g1(31)+lp2*g1(32))*s**2
 667       ge=gp0(17)+lp1*g1(33)+lp2*g1(34)+
 668      +  (gp0(18)+lp1*g1(35)+lp2*g1(36))*s
 669       gep=gp0(19)+lp1*g1(37)+lp2*g1(38)+
 670      +  (gp0(20)+lp1*g1(39)+lp2*g1(40))*s
 671       gpart1=grsf2(x,s,alp,bet,a,b,ga,gb,gc,gd,ge,gep)
 672 c
 673       s=log(log(q2/lam2)/log(mu2/lam2))
 674       suppr=1.d0/(1.d0+p2/0.59d0)**2
 675 c
 676       alp=ud2(1)
 677       bet=ud2(2)
 678       a=ud2(3)+ud2(4)*s
 679       ga=ud2(5)+ud2(6)*s**0.5
 680       gc=ud2(7)+ud2(8)*s
 681       b=ud2(9)+ud2(10)*s+ud2(11)*s**2
 682       gb=ud2(12)+ud2(13)*s+ud2(14)*s**2
 683       gd=ud2(15)+ud2(16)*s
 684       ge=ud2(17)+ud2(18)*s
 685       gep=ud2(19)+ud2(20)*s
 686       udpart2=suppr*grsf1(x,s,alp,bet,a,b,ga,gb,gc,gd,ge,gep)
 687 c
 688       alp=s2(1)
 689       bet=s2(2)
 690       a=s2(3)+s2(4)*s
 691       ga=s2(5)+s2(6)*s**0.5
 692       gc=s2(7)+s2(8)*s
 693       b=s2(9)+s2(10)*s+s2(11)*s**2
 694       gb=s2(12)+s2(13)*s+s2(14)*s**2
 695       gd=s2(15)+s2(16)*s
 696       ge=s2(17)+s2(18)*s
 697       gep=s2(19)+s2(20)*s
 698       spart2=suppr*grsf2(x,s,alp,bet,a,b,ga,gb,gc,gd,ge,gep)
 699 c
 700       alp=g2(1)
 701       bet=g2(2)
 702       a=g2(3)+g2(4)*s**0.5
 703       b=g2(5)+g2(6)*s**2
 704       gb=g2(7)+g2(8)*s
 705       ga=g2(9)+g2(10)*s**0.5+g2(11)*s**2
 706       gc=g2(12)+g2(13)*s**2
 707       gd=g2(14)+g2(15)*s+g2(16)*s**2
 708       ge=g2(17)+g2(18)*s
 709       gep=g2(19)+g2(20)*s
 710       gpart2=suppr*grsf1(x,s,alp,bet,a,b,ga,gb,gc,gd,ge,gep)
 711 c
 712       ugam=upart1+udpart2
 713       DUPV = UGAM * ALPHEM
 714       DUSEA = DUPV
 715       dgam=dspart1+udpart2
 716       DDNV = DGAM * ALPHEM
 717       DDSEA = DDNV
 718       sgam=dspart1+spart2
 719       DSTR = SGAM * ALPHEM
 720       ggam=gpart1+gpart2
 721       DGL = GGAM * ALPHEM
 722 C
 723       DCHM = 0.D0
 724       DBOT = 0.D0
 725 c
 726       return
 727       end
 728 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
 729        FUNCTION GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 730        IMPLICIT REAL (A - Z)
 731        SX = SQRT (X)
 732        LX = ALOG (1./X)
 733        GRVGF  = (X**AK * (AG + BG * SX + C * X**BK)  +  S**AL
 734      1       * EXP (-E + SQRT (ES * S**BE * LX))) * (1.- X)**D
 735        RETURN
 736        END
 737 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
 738        FUNCTION GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
 739        IMPLICIT REAL (A - Z)
 740        IF (S .LE. SF) THEN
 741           GRVGFS = 0.0
 742        ELSE
 743           SX = SQRT (X)
 744           LX = ALOG (1./X)
 745           DS = S - SF
 746           GRVGFS = (DS * X**AK * (AG + BG * SX + C * X**BK) + DS**AL
 747      1         * EXP (-E + SQRT (ES * S**BE * LX))) * (1.- X)**D
 748        END IF
 749        RETURN
 750        END
 751 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
 752       double precision function grsf1(x,s,alp,bet,a,b,ga,gb,gc,gd,
 753      +                                ge,gep)
 754       implicit real*8 (a-h,o-z)
 755 C
 756       grsf1=(x**a*(ga+gb*sqrt(x)+gc*x**b)+
 757      +      s**alp*exp(-ge+sqrt(gep*s**bet*log(1.d0/x))))*
 758      +      (1.d0-x)**gd
 759       return
 760       end
 761 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
 762       double precision function grsf2(x,s,alp,bet,a,b,ga,gb,gc,gd,
 763      +                                ge,gep)
 764       implicit real*8 (a-h,o-z)
 765 C
 766       grsf2=(s*x**a*(ga+gb*sqrt(x)+gc*x**b)+
 767      +      s**alp*exp(-ge+sqrt(gep*s**bet*log(1.d0/x))))*
 768      +      (1.d0-x)**gd
 769       return
 770       end
 771 ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
 772