DEMPgen/include/Constants.hxx

0001 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
0002   Declaration of constants for use throughout the program
0003   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
0004
0005 #ifndef Constants_H
0006 #define Constants_H
0007
0008 #include "TMath.h"
0009
0010 namespace constants{
0011
0012   const double electron_mass_mev = 0.511;
0013   const double proton_mass_mev = 938.272;
0014   const double pion_mass_mev = 139.57;
0015   const double neutron_mass_mev =  939.565;
0016
0017   const double electron_mass_gev = 0.511/1000;
0018   const double proton_mass_gev = 938.272/1000;
0019   const double pion_mass_gev = 139.57/1000;
0020   const double neutron_mass_gev =  939.565/1000;
0021
0022   const double DEG = 180.0/TMath::Pi();
0023
0024   const int pid_pion = -211;
0025   const int pid_prot = 2212;
0026   const int pid_elec = 11;
0027   const int pid_neut = 0;
0028   const int pid_phot = 22;
0029
0030   //const double EBeam = 11000;
0031   //const double PSF = ((EBeam*0.9-EBeam*0.1)/1000)
0032   //  * (28.0-5.0)/DEG * 2*TMath::Pi()
0033   //  *((EBeam*0.9-EBeam*0.1)/1000)
0034   //  * (60.0-0.0)/DEG * 2*TMath::Pi();
0035   const double Lumi = 1.0e36;
0036   const double nBcm2 = 1.0e-33;
0037   const double uBcm2 = 1.0e-30;
0038
0039   const double alpha = 1.0/137.0;
0040
0041
0042   //Helium
0043
0044   const double Helium_Z = 2.0;
0045   const double Helium_A = 4.002602;
0046   const double Helium_Density = 1.345e-3;
0047
0048   // Taget Window
0049
0050   const double Window_Density  = 2.76;    // g/cm^3
0051   const double Window_Thickness  = 19.4246; // g/cm2 this is equal to my X0
0052   const double Window_Thickness_RadLen = 7.038;    // cm
0053   const double Window_Z = 17;
0054   const double Window_A = 35;
0055
0056
0057   // Air
0058   const double Airtotal = (0.000124 + 0.755267
0059                            + 0.231781 + 0.012827);  //total mass of component of air
0060   const double Air_Z = int( 6 * 0.000124 / Airtotal + 7 * 0.755267
0061                             / Airtotal + 8 * 0.231781 / Airtotal + 18* 0.012827 / Airtotal);
0062   const double Air_A = Air_Z / 0.499;
0063   const double Air_Density = 1.205e-03;
0064
0065
0066 }
0067
0068 #endif