| Geant4 Cross Reference |
1 // -*- C++ -*- 1 // -*- C++ -*-
2 // ------------------------------------------- 2 // ----------------------------------------------------------------------
3 // HEP coherent Physical Constants 3 // HEP coherent Physical Constants
4 // 4 //
5 // This file has been provided by Geant4 (simu 5 // This file has been provided by Geant4 (simulation toolkit for HEP).
6 // 6 //
7 // The basic units are : 7 // The basic units are :
8 // millimeter 8 // millimeter
9 // nanosecond 9 // nanosecond
10 // Mega electron Volt 10 // Mega electron Volt
11 // positon charge 11 // positon charge
12 // degree Kelvin 12 // degree Kelvin
13 // amount of substance (mole) 13 // amount of substance (mole)
14 // luminous intensity (candela) 14 // luminous intensity (candela)
15 // radian 15 // radian
16 // steradian 16 // steradian
17 // 17 //
18 // Below is a non exhaustive list of Physical 18 // Below is a non exhaustive list of Physical CONSTANTS,
19 // computed in the Internal HEP System Of Unit 19 // computed in the Internal HEP System Of Units.
20 // 20 //
21 // Most of them are extracted from the Particl 21 // Most of them are extracted from the Particle Data Book :
22 // Phys. Rev. D volume 50 3-1 (1994) p 22 // Phys. Rev. D volume 50 3-1 (1994) page 1233
23 // 23 //
24 // ...with a meaningful (?) name ... 24 // ...with a meaningful (?) name ...
25 // 25 //
26 // You can add your own constants. 26 // You can add your own constants.
27 // 27 //
28 // Author: M.Maire 28 // Author: M.Maire
29 // 29 //
30 // History: 30 // History:
31 // 31 //
32 // 23.02.96 Created 32 // 23.02.96 Created
33 // 26.03.96 Added constants for standard condi 33 // 26.03.96 Added constants for standard conditions of temperature
34 // and pressure; also added Gas thres 34 // and pressure; also added Gas threshold.
35 // 29.04.08 Use PDG 2006 values << 35 // 29.04.08 use PDG 2006 values
36 // 03.11.08 Use PDG 2008 values << 36 // 03.11.08 use PDG 2008 values
37 // 17.07.20 Use PDG 2019 values <<
38 // 06.05.21 Added Bohr_magneton and nuclear_ma <<
39 37
40 #ifndef HEP_PHYSICAL_CONSTANTS_H 38 #ifndef HEP_PHYSICAL_CONSTANTS_H
41 #define HEP_PHYSICAL_CONSTANTS_H 39 #define HEP_PHYSICAL_CONSTANTS_H
42 40
43 #include "CLHEP/Units/SystemOfUnits.h" 41 #include "CLHEP/Units/SystemOfUnits.h"
44 42
45 namespace CLHEP { 43 namespace CLHEP {
46 44
47 // 45 //
48 // 46 //
49 // 47 //
50 static constexpr double Avogadro = 6.02214076e << 48 static constexpr double Avogadro = 6.02214179e+23/mole;
51 49
52 // 50 //
53 // c = 299.792458 mm/ns 51 // c = 299.792458 mm/ns
54 // c^2 = 898.7404 (mm/ns)^2 52 // c^2 = 898.7404 (mm/ns)^2
55 // 53 //
56 static constexpr double c_light = 2.99792458 54 static constexpr double c_light = 2.99792458e+8 * m/s;
57 static constexpr double c_squared = c_light * 55 static constexpr double c_squared = c_light * c_light;
58 56
59 // 57 //
60 // h = 4.13566e-12 MeV*ns 58 // h = 4.13566e-12 MeV*ns
61 // hbar = 6.58212e-13 MeV*ns 59 // hbar = 6.58212e-13 MeV*ns
62 // hbarc = 197.32705e-12 MeV*mm 60 // hbarc = 197.32705e-12 MeV*mm
63 // 61 //
64 static constexpr double h_Planck = 6.6260 << 62 static constexpr double h_Planck = 6.62606896e-34 * joule*s;
65 static constexpr double hbar_Planck = h_Plan 63 static constexpr double hbar_Planck = h_Planck/twopi;
66 static constexpr double hbarc = hbar_P 64 static constexpr double hbarc = hbar_Planck * c_light;
67 static constexpr double hbarc_squared = hbarc 65 static constexpr double hbarc_squared = hbarc * hbarc;
68 66
69 // 67 //
70 // 68 //
71 // 69 //
72 static constexpr double electron_charge = - ep 70 static constexpr double electron_charge = - eplus; // see SystemOfUnits.h
73 static constexpr double e_squared = eplus * ep 71 static constexpr double e_squared = eplus * eplus;
74 72
75 // 73 //
76 // amu_c2 - atomic equivalent mass unit 74 // amu_c2 - atomic equivalent mass unit
77 // - AKA, unified atomic mass unit (u) 75 // - AKA, unified atomic mass unit (u)
78 // amu - atomic mass unit 76 // amu - atomic mass unit
79 // 77 //
80 static constexpr double electron_mass_c2 = 0.5 78 static constexpr double electron_mass_c2 = 0.510998910 * MeV;
81 static constexpr double proton_mass_c2 = 938 79 static constexpr double proton_mass_c2 = 938.272013 * MeV;
82 static constexpr double neutron_mass_c2 = 939 80 static constexpr double neutron_mass_c2 = 939.56536 * MeV;
83 static constexpr double amu_c2 = 931 81 static constexpr double amu_c2 = 931.494028 * MeV;
84 static constexpr double amu = amu 82 static constexpr double amu = amu_c2/c_squared;
85 83
86 // 84 //
87 // permeability of free space mu0 = 2.01334 85 // permeability of free space mu0 = 2.01334e-16 Mev*(ns*eplus)^2/mm
88 // permittivity of free space epsil0 = 5.52636 86 // permittivity of free space epsil0 = 5.52636e+10 eplus^2/(MeV*mm)
89 // 87 //
90 static constexpr double mu0 = 4*pi*1.e-7 88 static constexpr double mu0 = 4*pi*1.e-7 * henry/m;
91 static constexpr double epsilon0 = 1./(c_squar 89 static constexpr double epsilon0 = 1./(c_squared*mu0);
92 90
93 // 91 //
94 // electromagnetic coupling = 1.43996e-12 MeV* 92 // electromagnetic coupling = 1.43996e-12 MeV*mm/(eplus^2)
95 // 93 //
96 static constexpr double elm_coupling 94 static constexpr double elm_coupling = e_squared/(4*pi*epsilon0);
97 static constexpr double fine_structure_const 95 static constexpr double fine_structure_const = elm_coupling/hbarc;
98 static constexpr double classic_electr_radius 96 static constexpr double classic_electr_radius = elm_coupling/electron_mass_c2;
99 static constexpr double electron_Compton_lengt 97 static constexpr double electron_Compton_length = hbarc/electron_mass_c2;
100 static constexpr double Bohr_radius = electron 98 static constexpr double Bohr_radius = electron_Compton_length/fine_structure_const;
101 99
102 static constexpr double alpha_rcl2 = fine_stru 100 static constexpr double alpha_rcl2 = fine_structure_const
103 *classic_el 101 *classic_electr_radius
104 *classic_el 102 *classic_electr_radius;
105 103
106 static constexpr double twopi_mc2_rcl2 = twopi 104 static constexpr double twopi_mc2_rcl2 = twopi*electron_mass_c2
107 * 105 *classic_electr_radius
108 * 106 *classic_electr_radius;
109 <<
110 static constexpr double Bohr_magneton = (eplus <<
111 static constexpr double nuclear_magneton = (ep <<
112 <<
113 // 107 //
114 // 108 //
115 // 109 //
116 static constexpr double k_Boltzmann = 8.617333 << 110 static constexpr double k_Boltzmann = 8.617343e-11 * MeV/kelvin;
117 111
118 // 112 //
119 // 113 //
120 // 114 //
121 static constexpr double STP_Temperature = 273. 115 static constexpr double STP_Temperature = 273.15*kelvin;
122 static constexpr double STP_Pressure = 1.*a 116 static constexpr double STP_Pressure = 1.*atmosphere;
123 static constexpr double kGasThreshold = 10.* 117 static constexpr double kGasThreshold = 10.*mg/cm3;
124 118
125 // 119 //
126 // 120 //
127 // 121 //
128 static constexpr double universe_mean_density 122 static constexpr double universe_mean_density = 1.e-25*g/cm3;
129 123
130 } // namespace CLHEP 124 } // namespace CLHEP
131 125
132 #endif /* HEP_PHYSICAL_CONSTANTS_H */ 126 #endif /* HEP_PHYSICAL_CONSTANTS_H */
133 127
134 128
135 129
136 130
137 131
138 132