PDF/spdf/structf.F

   1 *
   2 * $Id$
   3 *
   4 * $Log$
   5 * Revision 1.1.1.2  1996/10/30 08:31:55  cernlib
   6 * Version 7.04
   7 *
   8 * Revision 1.1.1.1  1996/04/12 15:30:06  plothow
   9 * Version 7.01
  10 *
  11 *
  12 #include "pdf/pilot.h"
  13 C
  14 C-----------------------------------------------------------------------
  15 C
  16       SUBROUTINE STRUCTF(X,SCALE,UPV,DNV,SEA,STR,CHM,BOT,TOP,GL)
  17 C
  18 C  *********************************************************************
  19 C  *                                                                   *
  20 C  *             Interface to main steering routine                    *
  21 C  *             for all sets of structure functions                   *
  22 C  *                                                                   *
  23 C  *                                                                   *
  24 C  *   Input:    X     = x value of parton                             *
  25 C  *             SCALE = QCD scale in GeV                              *
  26 C  *                                                                   *
  27 C  *   Output:   UPV   = up valence quark                              *
  28 C  *             DNV   = down valence quark                            *
  29 C  *             SEA   = sea (up and down)                             *
  30 C  *             STR   = strange quark                                 *
  31 C  *             CHM   = charm quark                                   *
  32 C  *             BOT   = bottom quark                                  *
  33 C  *             TOP   = top quark                                     *
  34 C  *             GL    = gluon                                         *
  35 C  *                                                                   *
  36 C  *                                                                   *
  37 C  *   The variable  MODE  should be,                                  *
  38 C  *   the variables NFL,LO,TMAS,QCDL4,QCDL5,XMIN,XMAX,Q2MIN,Q2MAX     *
  39 C  *   could be provided by the user via a call to the                 *
  40 C  *   subroutine PDFSET at the initialization phase, where            *
  41 C  *                                                                   *
  42 C  *             MODE   = number of selected structure function        *
  43 C  *                      (Default: MODE = 45)                         *
  44 C  *             NFL    = desired number of flavours for alpha(s)      *
  45 C  *                      (Default: NFL = 5)                           *
  46 C  *             LO     = order of alpha(s) calculation                *
  47 C  *                      (Default: LO = 2)                            *
  48 C  *             TMAS   = top quark mass in GeV/c**2  (optional)       *
  49 C  *                      (Default: TMAS = 100.0D0)                    *
  50 C  *             QCDL4  = QCD scale in GeV for four flavours           *
  51 C  *             QCDL5  = QCD scale in GeV for five flavours           *
  52 C  *                      corresponding to QCDL4                       *
  53 C  *             XMIN   = minimal allowed x value                      *
  54 C  *             XMAX   = maximal allowed x value                      *
  55 C  *             Q2MIN  = minimal allowed Q**2 value                   *
  56 C  *             Q2MAX  = maximal allowed Q**2 value                   *
  57 C  *                                                                   *
  58 C  *   for each set of structure fuction.                              *
  59 C  *                                                                   *
  60 C  *   The internal COMMON blocks                                      *
  61 C  *                                                                   *
  62 C  *   COMMON/W50511/ MODE,NFL,LO,NDUMMY,TMAS                          *
  63 C  *   COMMON/W50512/ QCDL4,QCDL5                                      *
  64 C  *   COMMON/W50513/ XMIN,XMAX,Q2MIN,Q2MAX                            *
  65 C  *                                                                   *
  66 C  *   are filled then by the subroutine PDFSET.                       *
  67 C  *                                                                   *
  68 C  *                                                                   *
  69 C  *     Note: STRUCTF returns X * parton distribution function !      *
  70 C  *                                                                   *
  71 C  *                                                                   *
  72 C  *     Author:   H. Plothow-Besch                                    *
  73 C  *               CERN-PPE, CH - 1211 Geneva 23, Switzerland          *
  74 C  *                                                                   *
  75 C  *     Please return any problems, questions, suggestions            *
  76 C  *     to the author                                                 *
  77 C  *                                                                   *
  78 C  *********************************************************************
  79 C
  80 C
  81 #include "pdf/impdp.inc"
  82 C
  83         CALL STRUCTM(X,SCALE,UPV,DNV,USEA,DSEA,STR,CHM,BOT,TOP,GL)
  84         SEA = (USEA + DSEA)/2.
  85 C
  86       RETURN
  87       END