StRoot: StarClassLibrary/PhysicalConstants.h Source File

00001 /***************************************************************************
00002  *
00003  * $Id: PhysicalConstants.h,v 1.2 1999/02/22 16:52:47 didenko Exp $
00004  *
00005  * Author: CLHEP (see below)
00006  ***************************************************************************
00007  *
00008  * Description:  Taken as-is from CLHEP.
00009  *               Modified original CVS-Id to retain version info. 
00010  ***************************************************************************
00011  *
00012  * $Log: PhysicalConstants.h,v $
00013  * Revision 1.2  1999/02/22 16:52:47  didenko
00014  * updates from Gene
00015  *
00016  * Revision 1.1  1999/01/30 03:58:59  fisyak
00017  * Root Version of StarClassLibrary
00018  *
00019  * Revision 1.1  1999/01/23 00:27:34  ullrich
00020  * Initial Revision
00021  *
00022  **************************************************************************/
00023 
00024 #ifndef HEP_PHYSICAL_CONSTANTS_H
00025 #define HEP_PHYSICAL_CONSTANTS_H
00026 
00027 #include "SystemOfUnits.h"
00028 #include <math.h>
00029 
00030 #ifndef ST_NO_NAMESPACES
00031 using namespace units;
00032 #endif
00033 
00034 //
00035 //
00036 //
00037 static const double     pi  = M_PI;    // from <math.h>
00038 static const double  twopi  = 2*pi;
00039 static const double halfpi  = pi/2;
00040 static const double    pi2  = pi*pi;
00041 
00042 //
00043 // 
00044 //
00045 static const double Avogadro = 6.0221367e+23/mole;
00046 
00047 //
00048 // c   = 299.792458 mm/ns
00049 // c^2 = 898.7404 (mm/ns)^2 
00050 //
00051 static const double c_light   = 2.99792458e+8 * meter/second;
00052 static const double c_squared = c_light * c_light;
00053 
00054 //
00055 // h     = 4.13566e-12 MeV*ns
00056 // hbar  = 6.58212e-13 MeV*ns
00057 // hbarc = 197.32705e-12 MeV*mm
00058 //
00059 static const double h_Planck      = 6.6260755e-34 * joule*second;
00060 static const double hbar_Planck   = h_Planck/twopi;
00061 static const double hbarc         = hbar_Planck * c_light;
00062 static const double hbarc_squared = hbarc * hbarc;
00063 
00064 //
00065 //
00066 //
00067 static const double electron_charge = - eplus; // see SystemOfUnits.h
00068 static const double e_squared = eplus * eplus;
00069 
00070 //
00071 // amu_c2 - atomic equivalent mass unit
00072 // amu    - atomic mass unit
00073 //
00074 static const double electron_mass_c2 = 0.51099906 * MeV;
00075 static const double   proton_mass_c2 = 938.27231 * MeV;
00076 static const double  neutron_mass_c2 = 939.56563 * MeV;
00077 static const double           amu_c2 = 931.49432 * MeV;
00078 static const double              amu = amu_c2/c_squared;
00079 
00080 static const double kaon_0_short_mass_c2 = 497.672  * MeV;
00081 static const double    pion_plus_mass_c2 = 139.5700 * MeV;
00082 static const double   pion_minus_mass_c2 = 139.5700 * MeV;
00083 static const double       lambda_mass_c2 = 1115.684 * MeV;
00084 static const double   antilambda_mass_c2 = 1115.684 * MeV;
00085 static const double     xi_minus_mass_c2 = 1321.32  * MeV;
00086 
00087 
00088 //
00089 // permeability of free space mu0    = 2.01334e-16 Mev*(ns*eplus)^2/mm
00090 // permittivity of free space epsil0 = 5.52636e+10 eplus^2/(MeV*mm)
00091 //
00092 static const double mu0      = 4*pi*1.e-7 * henry/meter;
00093 static const double epsilon0 = 1./(c_squared*mu0);
00094 
00095 //
00096 // electromagnetic coupling = 1.43996e-12 MeV*mm/(eplus^2)
00097 //
00098 static const double elm_coupling           = e_squared/(4*pi*epsilon0);
00099 static const double fine_structure_const   = elm_coupling/hbarc;
00100 static const double classic_electr_radius  = elm_coupling/electron_mass_c2;
00101 static const double electron_Compton_length = hbarc/electron_mass_c2;
00102 static const double Bohr_radius = electron_Compton_length/fine_structure_const;
00103 
00104 static const double alpha_rcl2 = fine_structure_const
00105                                    *classic_electr_radius
00106                                    *classic_electr_radius;
00107 
00108 static const double twopi_mc2_rcl2 = twopi*electron_mass_c2
00109                                              *classic_electr_radius
00110                                              *classic_electr_radius;
00111 //
00112 //
00113 //
00114 static const double k_Boltzmann = 8.617385e-11 * MeV/kelvin;
00115 
00116 //
00117 //
00118 //
00119 static const double STP_Temperature = 273.15*kelvin;
00120 static const double STP_Pressure    = 1.*atmosphere;
00121 static const double kGasThreshold   = 1.e-2*gram/centimeter3;
00122 
00123 #endif /* HEP_PHYSICAL_CONSTANTS_H */
00124 
00125 
00126 
00127 
00128