TEvtGen/EvtGenModels/EvtbTosllAliFF.cxx

   1 //--------------------------------------------------------------------------
   2 //
   3 // Environment:
   4 //      This software is part of the EvtGen package developed jointly
   5 //      for the BaBar and CLEO collaborations.  If you use all or part
   6 //      of it, please give an appropriate acknowledgement.
   7 //
   8 // Copyright Information: See EvtGen/COPYRIGHT
   9 //      Copyright (C) 2000      Caltech, UCSB
  10 //
  11 // Module:
  12 // Description: Form factors for b->sll according to Ali '02 et al.
  13 //              PRD 66 34002
  14 //
  15 // Modification history:
  16 //
  17 //    Ryd     March 30, 2003         Module created
  18 //
  19 //------------------------------------------------------------------------
  20 #include "EvtGenBase/EvtPatches.hh"
  21
  22 #include "EvtGenBase/EvtPatches.hh"
  23 #include "EvtGenBase/EvtPDL.hh"
  24 #include "EvtGenModels/EvtbTosllAliFF.hh"
  25 #include <math.h>
  26
  27 EvtbTosllAliFF::EvtbTosllAliFF(){}
  28
  29
  30 void EvtbTosllAliFF::getScalarFF(EvtId parent, EvtId daught,
  31                                  double t, double /*mass*/,
  32                                  double& fp,double& f0,double& ft){
  33
  34   double m=EvtPDL::getMeanMass(parent);
  35   //double md=EvtPDL::getMeanMass(daught);
  36
  37   double shat=t/(m*m);
  38   double shat2=shat*shat;
  39   double shat3=shat2*shat;
  40
  41   fp = 0.278*exp(1.568*shat+0.470*shat2+0.885*shat3);
  42   f0 = 0.278*exp(0.740*shat+0.080*shat2+0.425*shat3);
  43   ft = 0.300*exp(1.600*shat+0.501*shat2+0.796*shat3);
  44
  45 }
  46
  47
  48 void EvtbTosllAliFF::getVectorFF(EvtId parent, EvtId daught,
  49                                  double t, double /*mass*/,
  50                                  double& a1,double& a2,double& a0, double& v,
  51                                  double& t1, double& t2, double& t3 ){
  52
  53
  54   double m=EvtPDL::getMeanMass(parent);
  55
  56   double shat=t/(m*m);
  57   double shat2=shat*shat;
  58
  59   //this is Ali 'minimum allowed form factors'
  60   a1=0.294*exp(0.656*shat+0.456*shat2);
  61   a2=0.246*exp(1.237*shat+0.822*shat2);
  62   a0=0.412*exp(1.543*shat+0.954*shat2);
  63   v=0.399*exp(1.537*shat+1.123*shat2);
  64
  65   t1=0.334*exp(1.575*shat+1.140*shat2);
  66   t2=0.334*exp(0.562*shat+0.481*shat2);
  67   t3=0.234*exp(1.230*shat+1.089*shat2);
  68
  69 }
  70
  71