// @(#)root/eg:$Name:  $:$Id: TDatabasePDG.cxx,v 1.27 2006/11/16 17:17:37 rdm Exp $
// Author: Pasha Murat   12/02/99

/*************************************************************************
 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

#ifdef R__HAVE_CONFIG
#include "RConfigure.h"
#endif

#include "TROOT.h"
#include "TEnv.h"
#include "TSystem.h"
#include "TDatabasePDG.h"
#include "TDecayChannel.h"
#include "TParticlePDG.h"


////////////////////////////////////////////////////////////////////////
//
//  Particle database manager class
//
//  This manager creates a list of particles which by default is
//  initialised from with the constants used by PYTHIA6 (plus some
//  other particles added). See definition and the format of the default
//  particle list in $ROOTSYS/etc/pdg_table.txt
//
//  there are 2 ways of redefining the name of the file containing the
//  particle properties
//
//  1. one can define the name in .rootrc file:
//
//  Root.DatabasePDG: $(HOME)/my_pdg_table.txt
//
//  2. one can use TDatabasePDG::ReadPDGTable method explicitly:
//
//     - TDatabasePDG *pdg = new TDatabasePDG();
//     - pdg->ReadPDGtable(filename)
//
//  See TParticlePDG for the description of a static particle properties.
//  See TParticle    for the description of a dynamic particle particle.
//
////////////////////////////////////////////////////////////////////////

ClassImp(TDatabasePDG)

TDatabasePDG*  TDatabasePDG::fgInstance = 0;

//______________________________________________________________________________
TDatabasePDG::TDatabasePDG(): TNamed("PDGDB","The PDG particle data base")
{
  // Create PDG database. Initialization of the DB has to be done via explicit
  // call to ReadDataBasePDG (also done by GetParticle methods)

   fParticleList  = 0;
   fListOfClasses = 0;
      if (fgInstance) {
      Warning("TDatabasePDG", "object already instantiated");
   } else {
      fgInstance = this;
      gROOT->GetListOfSpecials()->Add(this);
   }
}

//______________________________________________________________________________
TDatabasePDG::~TDatabasePDG()
{
   // Cleanup the PDG database.

   if (fParticleList) {
      fParticleList->Delete();
      delete fParticleList;
   }
                                // classes do not own particles...
   if (fListOfClasses) delete fListOfClasses;
   gROOT->GetListOfSpecials()->Remove(this);
   fgInstance = 0;
}

//______________________________________________________________________________
TDatabasePDG*  TDatabasePDG::Instance()
{
   //static function
   return (fgInstance) ? (TDatabasePDG*) fgInstance : new TDatabasePDG();
}


//______________________________________________________________________________
TParticlePDG* TDatabasePDG::AddParticle(const char *name, const char *title,
                                        Double_t mass, Bool_t stable,
                                        Double_t width, Double_t charge,
                                        const char* ParticleClass,
                                        Int_t PDGcode,
                                        Int_t Anti,
                                        Int_t TrackingCode)
{
  //
  //  Particle definition normal constructor. If the particle is set to be
  //  stable, the decay width parameter does have no meaning and can be set to
  //  any value. The parameters granularity, LowerCutOff and HighCutOff are
  //  used for the construction of the mean free path look up tables. The
  //  granularity will be the number of logwise energy points for which the
  //  mean free path will be calculated.
  //

   TParticlePDG* old = GetParticle(PDGcode);

   if (old) {
      printf(" *** TDatabasePDG::AddParticle: particle with PDGcode=%d already defined\n",PDGcode);
      return 0;
   }

   TParticlePDG* p = new TParticlePDG(name, title, mass, stable, width,
                                     charge, ParticleClass, PDGcode, Anti,
                                     TrackingCode);
   fParticleList->Add(p);

   TParticleClassPDG* pclass = GetParticleClass(ParticleClass);

   if (!pclass) {
      pclass = new TParticleClassPDG(ParticleClass);
      fListOfClasses->Add(pclass);
   }

   pclass->AddParticle(p);

   return p;
}

//______________________________________________________________________________
TParticlePDG* TDatabasePDG::AddAntiParticle(const char* Name, Int_t PdgCode)
{
   // assuming particle has already been defined

   TParticlePDG* old = GetParticle(PdgCode);

   if (old) {
      printf(" *** TDatabasePDG::AddAntiParticle: can't redefine parameters\n");
      return NULL;
   }

   Int_t pdg_code  = abs(PdgCode);
   TParticlePDG* p = GetParticle(pdg_code);

   TParticlePDG* ap = AddParticle(Name,
                                  Name,
                                  p->Mass(),
                                  1,
                                  p->Width(),
                                  -p->Charge(),
                                  p->ParticleClass(),
                                  PdgCode,
                                  1,
                                  p->TrackingCode());
   return ap;
}


//______________________________________________________________________________
TParticlePDG *TDatabasePDG::GetParticle(const char *name) const
{
   //
   //  Get a pointer to the particle object according to the name given
   //

   if (fParticleList == 0)  ((TDatabasePDG*)this)->ReadPDGTable();

   TParticlePDG *def = (TParticlePDG *)fParticleList->FindObject(name);
//     if (!def) {
//        Error("GetParticle","No match for %s exists!",name);
//     }
   return def;
}

//______________________________________________________________________________
TParticlePDG *TDatabasePDG::GetParticle(Int_t PDGcode) const
{
   //
   //  Get a pointer to the particle object according to the MC code number
   //

   if (fParticleList == 0)  ((TDatabasePDG*)this)->ReadPDGTable();

   TParticlePDG *p;
   TObjLink *lnk = fParticleList->FirstLink();
   while (lnk) {
      p = (TParticlePDG*)lnk->GetObject();
      if (p->PdgCode() == PDGcode) return p;
      lnk = lnk->Next();
   }
   //   Error("GetParticle","No match for PDG code %d exists!",PDGcode);
   return 0;
}

//______________________________________________________________________________
void TDatabasePDG::Print(Option_t *option) const
{
   // Print contents of PDG database.

   if (fParticleList == 0)  ((TDatabasePDG*)this)->ReadPDGTable();

   TIter next(fParticleList);
   TParticlePDG *p;
   while ((p = (TParticlePDG *)next())) {
      p->Print(option);
   }
}

//______________________________________________________________________________
Int_t TDatabasePDG::ConvertGeant3ToPdg(Int_t Geant3number) {
  // Converts Geant3 particle codes to PDG convention. (Geant4 uses
  // PDG convention already)
  // Source: BaBar User Guide, Neil I. Geddes,
  //
  //Begin_Html
  /*
   see <A href="http://www.slac.stanford.edu/BFROOT/www/Computing/Environment/NewUser/htmlbug/node51.html"> Conversion table</A>
  */
  //End_Html
  // with some fixes by PB, marked with (PB) below. Checked against
  // PDG listings from 2000.
  //
  // Paul Balm, Nov 19, 2001

   switch(Geant3number) {

      case 1   : return 22;       // photon
      case 25  : return -2112;    // anti-neutron
      case 2   : return -11;      // e+
      case 26  : return -3122;    // anti-Lambda
      case 3   : return 11;       // e-
      case 27  : return -3222;    // Sigma-
      case 4   : return 12;       // e-neutrino (NB: flavour undefined by Geant)
      case 28  : return -3212;    // Sigma0
      case 5   : return -13;      // mu+
      case 29  : return -3112;    // Sigma+ (PB)*/
      case 6   : return 13;       // mu-
      case 30  : return -3322;    // Xi0
      case 7   : return 111;      // pi0
      case 31  : return -3312;    // Xi+
      case 8   : return 211;      // pi+
      case 32  : return -3334;    // Omega+ (PB)
      case 9   : return -211;     // pi-
      case 33  : return -15;      // tau+
      case 10  : return 130;      // K long
      case 34  : return 15;       // tau-
      case 11  : return 321;      // K+
      case 35  : return 411;      // D+
      case 12  : return -321;     // K-
      case 36  : return -411;     // D-
      case 13  : return 2112;     // n
      case 37  : return 421;      // D0
      case 14  : return 2212;     // p
      case 38  : return -421;     // D0
      case 15  : return -2212;    // anti-proton
      case 39  : return 431;      // Ds+
      case 16  : return 310;      // K short
      case 40  : return -431;     // anti Ds-
      case 17  : return 221;      // eta
      case 41  : return 4122;     // Lamba_c+
      case 18  : return 3122;     // Lambda
      case 42  : return 24;       // W+
      case 19  : return 3222;     // Sigma+
      case 43  : return -24;      // W-
      case 20  : return 3212;     // Sigma0
      case 44  : return 23;       // Z
      case 21  : return 3112;     // Sigma-
      case 45  : return 0;        // deuteron
      case 22  : return 3322;     // Xi0
      case 46  : return 0;        // triton
      case 23  : return 3312;     // Xi-
      case 47  : return 0;        // alpha
      case 24  : return 3334;     // Omega- (PB)
      case 48  : return 0;        // G nu ? PDG ID 0 is undefined

      default  : return 0;

   }
}

//______________________________________________________________________________
Int_t TDatabasePDG::ConvertPdgToGeant3(Int_t pdgNumber) {
   // Converts pdg code to geant3 id

   switch(pdgNumber) {

      case   22     : return  1;    // photon
      case   -2112  : return  25;   // anti-neutron
      case   -11    : return  2;    // e+
      case   -3122  : return  26;   // anti-Lambda
      case   11     : return  3;    // e-
      case   -3222  : return  27;   // Sigma-
      case   12     : return  4;    // e-neutrino (NB: flavour undefined by Geant)
      case   -3212  : return  28;   // Sigma0
      case   -13    : return  5;    // mu+
      case   -3112  : return  29;   // Sigma+ (PB)*/
      case   13     : return  6;    // mu-
      case   -3322  : return  30;   // Xi0
      case   111    : return  7;    // pi0
      case   -3312  : return  31;   // Xi+
      case   211    : return  8;    // pi+
      case   -3334  : return  32;   // Omega+ (PB)
      case   -211   : return  9;    // pi-
      case   -15    : return  33;   // tau+
      case   130    : return  10;   // K long
      case   15     : return  34;   // tau-
      case   321    : return  11;   // K+
      case   411    : return  35;   // D+
      case   -321   : return  12;   // K-
      case   -411   : return  36;   // D-
      case   2112   : return  13;   // n
      case   421    : return  37;   // D0
      case   2212   : return  14;   // p
      case   -421   : return  38;   // D0
      case   -2212  : return  15;   // anti-proton
      case   431    : return  39;   // Ds+
      case   310    : return  16;   // K short
      case   -431   : return  40;   // anti Ds-
      case   221    : return  17;   // eta
      case   4122   : return  41;   // Lamba_c+
      case   3122   : return  18;   // Lambda
      case   24     : return  42;   // W+
      case   3222   : return  19;   // Sigma+
      case   -24    : return  43;   // W-
      case   3212   : return  20;   // Sigma0
      case   23     : return  44;   // Z
      case   3112   : return  21;   // Sigma-
      case   3322   : return  22;   // Xi0
      case   3312   : return  23;   // Xi-
      case   3334   : return  24;   // Omega- (PB)

      default  : return 0;

   }
}

//______________________________________________________________________________
Int_t TDatabasePDG::ConvertIsajetToPdg(Int_t isaNumber)
{
//
//  Converts the ISAJET Particle number into the PDG MC number
//
   switch (isaNumber) {
      case     1 : return     2; //     UP        .30000E+00       .67
      case    -1 : return    -2; //     UB        .30000E+00      -.67
      case     2 : return     1; //     DN        .30000E+00      -.33
      case    -2 : return    -1; //     DB        .30000E+00       .33
      case     3 : return     3; //     ST        .50000E+00      -.33
      case    -3 : return    -3; //     SB        .50000E+00       .33
      case     4 : return     4; //     CH        .16000E+01       .67
      case    -4 : return    -4; //     CB        .16000E+01      -.67
      case     5 : return     5; //     BT        .49000E+01      -.33
      case    -5 : return    -5; //     BB        .49000E+01       .33
      case     6 : return     6; //     TP        .17500E+03       .67
      case    -6 : return    -6; //     TB        .17500E+03      -.67
      case     9 : return    21; //     GL       0.               0.00
      case    80 : return    24; //     W+        SIN2W=.23       1.00
      case   -80 : return   -24; //     W-        SIN2W=.23      -1.00
      case    90 : return    23; //     Z0        SIN2W=.23       0.00
      case   230 : return   311; //     K0        .49767E+00      0.00
      case  -230 : return  -311; //     AK0       .49767E+00      0.00
      case   330 : return   331; //     ETAP      .95760E+00      0.00
      case   340 : return     0; //     F-        .20300E+01     -1.00
      case  -340 : return     0; //     F+        .20300E+01      1.00
      case   440 : return   441; //     ETAC      .29760E+01      0.00
      case   111 : return   113; //     RHO0      .77000E+00      0.00
      case   121 : return   213; //     RHO+      .77000E+00      1.00
      case  -121 : return  -213; //     RHO-      .77000E+00     -1.00
      case   221 : return   223; //     OMEG      .78260E+00      0.00
      case   131 : return   323; //     K*+       .88810E+00      1.00
      case  -131 : return  -323; //     K*-       .88810E+00     -1.00
      case   231 : return   313; //     K*0       .89220E+00      0.00
      case  -231 : return  -313; //     AK*0      .89220E+00      0.00
      case   331 : return   333; //     PHI       .10196E+01      0.00
      case  -140 : return   421; //     D0
      case   140 : return  -421; //     D0 bar
      case   141 : return  -423; //     AD*0      .20060E+01      0.00
      case  -141 : return   423; //     D*0       .20060E+01      0.00
      case  -240 : return  -411; //     D+
      case   240 : return   411; //     D-
      case   241 : return  -413; //     D*-       .20086E+01     -1.00
      case  -241 : return   413; //     D*+       .20086E+01      1.00
      case   341 : return     0; //     F*-       .21400E+01     -1.00
      case  -341 : return     0; //     F*+       .21400E+01      1.00
      case   441 : return   443; //     JPSI      .30970E+01      0.00

                                        // B-mesons, Bc still missing
      case   250 : return   511; // B0
      case  -250 : return  -511; // B0 bar
      case   150 : return   521; // B+
      case  -150 : return  -521; // B-
      case   350 : return   531; // Bs  0
      case  -350 : return  -531; // Bs  bar
      case   351 : return   533; // Bs* 0
      case  -351 : return  -533; // Bs* bar
      case   450 : return   541; // Bc  +
      case  -450 : return  -541; // Bc  bar

      case  1140 : return  4222; //     SC++      .24300E+01      2.00
      case -1140 : return -4222; //     ASC--     .24300E+01     -2.00
      case  1240 : return  4212; //     SC+       .24300E+01      1.00
      case -1240 : return -4212; //     ASC-      .24300E+01     -1.00
      case  2140 : return  4122; //     LC+       .22600E+01      1.00
      case -2140 : return -4122; //     ALC-      .22600E+01     -1.00
      case  2240 : return  4112; //     SC0       .24300E+01      0.00
      case -2240 : return -4112; //     ASC0      .24300E+01      0.00
      case  1340 : return     0; //     USC.      .25000E+01      1.00
      case -1340 : return     0; //     AUSC.     .25000E+01     -1.00
      case  3140 : return     0; //     SUC.      .24000E+01      1.00
      case -3140 : return     0; //     ASUC.     .24000E+01     -1.00
      case  2340 : return     0; //     DSC.      .25000E+01      0.00
      case -2340 : return     0; //     ADSC.     .25000E+01      0.00
      case  3240 : return     0; //     SDC.      .24000E+01      0.00
      case -3240 : return     0; //     ASDC.     .24000E+01      0.00
      case  3340 : return     0; //     SSC.      .26000E+01      0.00
      case -3340 : return     0; //     ASSC.     .26000E+01      0.00
      case  1440 : return     0; //     UCC.      .35500E+01      2.00
      case -1440 : return     0; //     AUCC.     .35500E+01     -2.00
      case  2440 : return     0; //     DCC.      .35500E+01      1.00
      case -2440 : return     0; //     ADCC.     .35500E+01     -1.00
      case  3440 : return     0; //     SCC.      .37000E+01      1.00
      case -3440 : return     0; //     ASCC.     .37000E+01     -1.00
      case  1111 : return  2224; //     DL++      .12320E+01      2.00
      case -1111 : return -2224; //     ADL--     .12320E+01     -2.00
      case  1121 : return  2214; //     DL+       .12320E+01      1.00
      case -1121 : return -2214; //     ADL-      .12320E+01     -1.00
      case  1221 : return  2114; //     DL0       .12320E+01      0.00
      case -1221 : return -2114; //     ADL0      .12320E+01      0.00
      case  2221 : return   1114; //     DL-       .12320E+01     -1.00
      case -2221 : return -1114; //     ADL+      .12320E+01      1.00
      case  1131 : return  3224; //     S*+       .13823E+01      1.00
      case -1131 : return -3224; //     AS*-      .13823E+01     -1.00
      case  1231 : return  3214; //     S*0       .13820E+01      0.00
      case -1231 : return -3214; //     AS*0      .13820E+01      0.00
      case  2231 : return  3114; //     S*-       .13875E+01     -1.00
      case -2231 : return -3114; //     AS*+      .13875E+01      1.00
      case  1331 : return  3324; //     XI*0      .15318E+01      0.00
      case -1331 : return -3324; //     AXI*0     .15318E+01      0.00
      case  2331 : return  3314; //     XI*-      .15350E+01     -1.00
      case -2331 : return -3314; //     AXI*+     .15350E+01      1.00
      case  3331 : return  3334; //     OM-       .16722E+01     -1.00
      case -3331 : return -3334; //     AOM+      .16722E+01      1.00
      case  1141 : return     0; //     UUC*      .26300E+01      2.00
      case -1141 : return     0; //     AUUC*     .26300E+01     -2.00
      case  1241 : return     0; //     UDC*      .26300E+01      1.00
      case -1241 : return     0; //     AUDC*     .26300E+01     -1.00
      case  2241 : return     0; //     DDC*      .26300E+01      0.00
      case -2241 : return     0; //     ADDC*     .26300E+01      0.00
      case  1341 : return     0; //     USC*      .27000E+01      1.00
      case -1341 : return     0; //     AUSC*     .27000E+01     -1.00
      case  2341 : return     0; //     DSC*      .27000E+01      0.00
      case -2341 : return     0; //     ADSC*     .27000E+01      0.00
      case  3341 : return     0; //     SSC*      .28000E+01      0.00
      case -3341 : return     0; //     ASSC*     .28000E+01      0.00
      case  1441 : return     0; //     UCC*      .37500E+01      2.00
      case -1441 : return     0; //     AUCC*     .37500E+01     -2.00
      case  2441 : return     0; //     DCC*      .37500E+01      1.00
      case -2441 : return     0; //     ADCC*     .37500E+01     -1.00
      case  3441 : return     0; //     SCC*      .39000E+01      1.00
      case -3441 : return     0; //     ASCC*     .39000E+01     -1.00
      case  4441 : return     0; //     CCC*      .48000E+01      2.00
      case -4441 : return     0; //     ACCC*     .48000E+01     -2.00
      case    10 : return    22; // Photon
      case    12 : return    11; // Electron
      case   -12 : return   -11; // Positron
      case    14 : return    13; // Muon-
      case   -14 : return   -13; // Muon+
      case    16 : return    15; // Tau-
      case   -16 : return   -15; // Tau+
      case    11 : return    12; // Neutrino e
      case   -11 : return   -12; // Anti Neutrino e
      case    13 : return    14; // Neutrino Muon
      case   -13 : return   -14; // Anti Neutrino Muon
      case    15 : return    16; // Neutrino Tau
      case   -15 : return   -16; // Anti Neutrino Tau
      case   110 : return   111; // Pion0
      case   120 : return   211; // Pion+
      case  -120 : return  -211; // Pion-
      case   220 : return   221; // Eta
      case   130 : return   321; // Kaon+
      case  -130 : return  -321; // Kaon-
      case   -20 : return   130; // Kaon Long
      case    20 : return   310; // Kaon Short

                                        // baryons
      case  1120 : return  2212; // Proton
      case -1120 : return -2212; // Anti Proton
      case  1220 : return  2112; // Neutron
      case -1220 : return -2112; // Anti Neutron
      case  2130 : return  3122; // Lambda
      case -2130 : return -3122; // Lambda bar
      case  1130 : return  3222; // Sigma+
      case -1130 : return -3222; // Sigma bar -
      case  1230 : return  3212; // Sigma0
      case -1230 : return -3212; // Sigma bar 0
      case  2230 : return  3112; // Sigma-
      case -2230 : return -3112; // Sigma bar +
      case  1330 : return  3322; // Xi0
      case -1330 : return -3322; // Xi bar 0
      case  2330 : return  3312; // Xi-
      case -2330 : return -3312; // Xi bar +
      default :    return 0;      // isajet or pdg number does not exist
   }
}

//______________________________________________________________________________
void TDatabasePDG::ReadPDGTable(const char *FileName)
{
   // read list of particles from a file
   // if the particle list does not exist, it is created, otherwise
   // particles are added to the existing list
   // See $ROOTSYS/etc/pdg_table.txt to see the file format

   if (fParticleList == 0) {
      fParticleList  = new THashList;
      fListOfClasses = new TObjArray;
   }

   TString default_name;
   const char *fn;

   if (strlen(FileName) == 0) {
#ifdef ROOTETCDIR
      default_name.Form("%s/pdg_table.txt", ROOTETCDIR);
#else
      default_name.Form("%s/etc/pdg_table.txt", gSystem->Getenv("ROOTSYS"));
#endif
      fn = gEnv->GetValue("Root.DatabasePDG", default_name.Data());
   } else {
      fn = FileName;
   }

   FILE* file = fopen(fn,"r");
   if (file == 0) {
      Error("ReadPDGTable","Could not open PDG particle file %s",fn);
      return;
   }

   char      c[512];
   Int_t     class_number, anti, isospin, i3, spin, tracking_code;
   Int_t     ich, kf, nch, charge;
   char      name[30], class_name[30];
   Double_t  mass, width, branching_ratio;
   Int_t     dau[20];

   Int_t     idecay, decay_type, flavor, ndau;

   while ( (c[0]=getc(file)) != EOF) {

      if (c[0] != '#') {
         ungetc(c[0],file);
         // read channel number
         fscanf(file,"%i",&ich);
         fscanf(file,"%s",name  );
         fscanf(file,"%i",&kf   );
         fscanf(file,"%i",&anti );

         if (kf < 0) {
            AddAntiParticle(name,kf);
            // nothing more on this line
            fgets(c,200,file);
         } else {
            fscanf(file,"%i",&class_number);
            fscanf(file,"%s",class_name);
            fscanf(file,"%i",&charge);
            fscanf(file,"%le",&mass);
            fscanf(file,"%le",&width);
            fscanf(file,"%i",&isospin);
            fscanf(file,"%i",&i3);
            fscanf(file,"%i",&spin);
            fscanf(file,"%i",&flavor);
            fscanf(file,"%i",&tracking_code);
            fscanf(file,"%i",&nch);
            // nothing more on this line
            fgets(c,200,file);


            // create particle

            TParticlePDG* part = AddParticle(name,
                                             name,
                                             mass,
                                             1,
                                             width,
                                             charge,
                                             class_name,
                                             kf,
                                             anti,
                                             tracking_code);

            if (nch) {
               // read in decay channels
               int ich = 0;
               while ( ((c[0]=getc(file)) != EOF) && (ich <nch)) {
                  if (c[0] != '#') {
                     ungetc(c[0],file);

                     fscanf(file,"%i",&idecay);
                     fscanf(file,"%i",&decay_type);
                     fscanf(file,"%le",&branching_ratio);
                     fscanf(file,"%i",&ndau);
                     for (int idau=0; idau<ndau; idau++) {
                        fscanf(file,"%i",&dau[idau]);
                     }
                     // add decay channel

                     part->AddDecayChannel(decay_type,branching_ratio,ndau,dau);
                     ich++;
                  }
                  // skip end of line
                  fgets(c,200,file);
               }
            }
         }
      } else {
         // skip end of line
         fgets(c,200,file);
      }
   }
   // in the end loop over the antiparticles and
   // define their decay lists
   TIter it(fParticleList);

   Int_t code[20];
   TParticlePDG  *ap, *p, *daughter;
   TDecayChannel dc;

   while ((p = (TParticlePDG*) it.Next())) {

      // define decay channels for antiparticles
      if (p->PdgCode() < 0) {
         ap = GetParticle(-p->PdgCode());
         nch = ap->NDecayChannels();
         for (int ich=0; ich<nch; ich++) {
            TDecayChannel* dc = ap->DecayChannel(ich);
            ndau = dc->NDaughters();
            for (int i=0; i<ndau; i++) {
               // conserve CPT

               code[i] = dc->DaughterPdgCode(i);
               daughter = GetParticle(code[i]);
               if (daughter->AntiParticle()) {
                  // this particle does have an
                  // antiparticle
                  code[i] = -code[i];
               }
            }
            p->AddDecayChannel(dc->MatrixElementCode(),
                               dc->BranchingRatio(),
                               dc->NDaughters(),
                               code);
         }
         p->SetAntiParticle(ap);
         ap->SetAntiParticle(p);
      }
   }

   fclose(file);
   return;
}


//______________________________________________________________________________
void TDatabasePDG::Browse(TBrowser* b)
{
   //browse data base
   if (fListOfClasses ) fListOfClasses->Browse(b);
}


//______________________________________________________________________________
Int_t TDatabasePDG::WritePDGTable(const char * /*filename*/)
{
   // write contents of the particle DB into a file

   Error("WritePDGTable"," not implemented yet");
   return 0;
/*
  if (1) return 0;

  FILE *file = fopen(filename,"w");
  if (file == 0) {
    Error("WritePDGTable","Could not open PDG particle file %s",filename);
    return -1;
  }

  fclose(file);
*/
}