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