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SystemOfUnits.h
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1// -*- C++ -*-
2// ----------------------------------------------------------------------
3// HEP coherent system of Units
4//
5// This file has been provided to CLHEP by Geant4 (simulation toolkit for HEP).
6//
7// The basic units are :
8// millimeter (millimeter)
9// nanosecond (nanosecond)
10// Mega electron Volt (MeV)
11// positron charge (eplus)
12// degree Kelvin (kelvin)
13// the amount of substance (mole)
14// luminous intensity (candela)
15// radian (radian)
16// steradian (steradian)
17//
18// Below is a non exhaustive list of derived and pratical units
19// (i.e. mostly the SI units).
20// You can add your own units.
21//
22// The SI numerical value of the positron charge is defined here,
23// as it is needed for conversion factor : positron charge = e_SI (coulomb)
24//
25// The others physical constants are defined in the header file :
26// PhysicalConstants.h
27//
28// Authors: M.Maire, S.Giani
29//
30// History:
31//
32// 06.02.96 Created.
33// 28.03.96 Added miscellaneous constants.
34// 05.12.97 E.Tcherniaev: Redefined pascal (to avoid warnings on WinNT)
35// 20.05.98 names: meter, second, gram, radian, degree
36// (from Brian.Lasiuk@yale.edu (STAR)). Added luminous units.
37// 05.08.98 angstrom, picobarn, microsecond, picosecond, petaelectronvolt
38// 01.03.01 parsec
39// 31.01.06 kilogray, milligray, microgray
40// 29.04.08 use PDG 2006 value of e_SI
41// 03.11.08 use PDG 2008 value of e_SI
42// 19.08.15 added liter and its sub units (mma)
43// 12.01.16 added symbols for microsecond (us) and picosecond (ps) (mma)
44// 17.07.20 use PDG 2019 value of e_SI
45
46#ifndef HEP_SYSTEM_OF_UNITS_H
47#define HEP_SYSTEM_OF_UNITS_H
48
49namespace CLHEP {
50
51 //
52 //
53 //
54 static constexpr double pi = 3.14159265358979323846;
55 static constexpr double twopi = 2*pi;
56 static constexpr double halfpi = pi/2;
57 static constexpr double pi2 = pi*pi;
58
59 //
60 // Length [L]
61 //
62 static constexpr double millimeter = 1.;
63 static constexpr double millimeter2 = millimeter*millimeter;
64 static constexpr double millimeter3 = millimeter*millimeter*millimeter;
65
66 static constexpr double centimeter = 10.*millimeter;
67 static constexpr double centimeter2 = centimeter*centimeter;
68 static constexpr double centimeter3 = centimeter*centimeter*centimeter;
69
70 static constexpr double meter = 1000.*millimeter;
71 static constexpr double meter2 = meter*meter;
72 static constexpr double meter3 = meter*meter*meter;
73
74 static constexpr double kilometer = 1000.*meter;
75 static constexpr double kilometer2 = kilometer*kilometer;
76 static constexpr double kilometer3 = kilometer*kilometer*kilometer;
77
78 static constexpr double parsec = 3.0856775807e+16*meter;
79
80 static constexpr double micrometer = 1.e-6 *meter;
81 static constexpr double nanometer = 1.e-9 *meter;
82 static constexpr double angstrom = 1.e-10*meter;
83 static constexpr double fermi = 1.e-15*meter;
84
85 static constexpr double barn = 1.e-28*meter2;
86 static constexpr double millibarn = 1.e-3 *barn;
87 static constexpr double microbarn = 1.e-6 *barn;
88 static constexpr double nanobarn = 1.e-9 *barn;
89 static constexpr double picobarn = 1.e-12*barn;
90
91 // symbols
92 static constexpr double nm = nanometer;
93 static constexpr double um = micrometer;
94
95 static constexpr double mm = millimeter;
96 static constexpr double mm2 = millimeter2;
97 static constexpr double mm3 = millimeter3;
98
99 static constexpr double cm = centimeter;
100 static constexpr double cm2 = centimeter2;
101 static constexpr double cm3 = centimeter3;
102
103 static constexpr double liter = 1.e+3*cm3;
104 static constexpr double L = liter;
105 static constexpr double dL = 1.e-1*liter;
106 static constexpr double cL = 1.e-2*liter;
107 static constexpr double mL = 1.e-3*liter;
108
109 static constexpr double m = meter;
110 static constexpr double m2 = meter2;
111 static constexpr double m3 = meter3;
112
113 static constexpr double km = kilometer;
114 static constexpr double km2 = kilometer2;
115 static constexpr double km3 = kilometer3;
116
117 static constexpr double pc = parsec;
118
119 //
120 // Angle
121 //
122 static constexpr double radian = 1.;
123 static constexpr double milliradian = 1.e-3*radian;
124 static constexpr double degree = (pi/180.0)*radian;
125
126 static constexpr double steradian = 1.;
127
128 // symbols
129 static constexpr double rad = radian;
130 static constexpr double mrad = milliradian;
131 static constexpr double sr = steradian;
132 static constexpr double deg = degree;
133
134 //
135 // Time [T]
136 //
137 static constexpr double nanosecond = 1.;
138 static constexpr double second = 1.e+9 *nanosecond;
139 static constexpr double millisecond = 1.e-3 *second;
140 static constexpr double microsecond = 1.e-6 *second;
141 static constexpr double picosecond = 1.e-12*second;
142
143 static constexpr double hertz = 1./second;
144 static constexpr double kilohertz = 1.e+3*hertz;
145 static constexpr double megahertz = 1.e+6*hertz;
146
147 // symbols
148 static constexpr double ns = nanosecond;
149 static constexpr double s = second;
150 static constexpr double ms = millisecond;
151 static constexpr double us = microsecond;
152 static constexpr double ps = picosecond;
153
154 //
155 // Electric charge [Q]
156 //
157 static constexpr double eplus = 1. ;// positron charge
158 static constexpr double e_SI = 1.602176634e-19;// positron charge in coulomb
159 static constexpr double coulomb = eplus/e_SI;// coulomb = 6.24150 e+18 * eplus
160
161 //
162 // Energy [E]
163 //
164 static constexpr double megaelectronvolt = 1. ;
165 static constexpr double electronvolt = 1.e-6*megaelectronvolt;
166 static constexpr double kiloelectronvolt = 1.e-3*megaelectronvolt;
167 static constexpr double gigaelectronvolt = 1.e+3*megaelectronvolt;
168 static constexpr double teraelectronvolt = 1.e+6*megaelectronvolt;
169 static constexpr double petaelectronvolt = 1.e+9*megaelectronvolt;
170
171 static constexpr double joule = electronvolt/e_SI;// joule = 6.24150 e+12 * MeV
172
173 // symbols
174 static constexpr double MeV = megaelectronvolt;
175 static constexpr double eV = electronvolt;
176 static constexpr double keV = kiloelectronvolt;
177 static constexpr double GeV = gigaelectronvolt;
178 static constexpr double TeV = teraelectronvolt;
179 static constexpr double PeV = petaelectronvolt;
180
181 //
182 // Mass [E][T^2][L^-2]
183 //
184 static constexpr double kilogram = joule*second*second/(meter*meter);
185 static constexpr double gram = 1.e-3*kilogram;
186 static constexpr double milligram = 1.e-3*gram;
187
188 // symbols
189 static constexpr double kg = kilogram;
190 static constexpr double g = gram;
191 static constexpr double mg = milligram;
192
193 //
194 // Power [E][T^-1]
195 //
196 static constexpr double watt = joule/second;// watt = 6.24150 e+3 * MeV/ns
197
198 //
199 // Force [E][L^-1]
200 //
201 static constexpr double newton = joule/meter;// newton = 6.24150 e+9 * MeV/mm
202
203 //
204 // Pressure [E][L^-3]
205 //
206#define pascal hep_pascal // a trick to avoid warnings
207 static constexpr double hep_pascal = newton/m2; // pascal = 6.24150 e+3 * MeV/mm3
208 static constexpr double bar = 100000*pascal; // bar = 6.24150 e+8 * MeV/mm3
209 static constexpr double atmosphere = 101325*pascal; // atm = 6.32420 e+8 * MeV/mm3
210
211 //
212 // Electric current [Q][T^-1]
213 //
214 static constexpr double ampere = coulomb/second; // ampere = 6.24150 e+9 * eplus/ns
215 static constexpr double milliampere = 1.e-3*ampere;
216 static constexpr double microampere = 1.e-6*ampere;
217 static constexpr double nanoampere = 1.e-9*ampere;
218
219 //
220 // Electric potential [E][Q^-1]
221 //
222 static constexpr double megavolt = megaelectronvolt/eplus;
223 static constexpr double kilovolt = 1.e-3*megavolt;
224 static constexpr double volt = 1.e-6*megavolt;
225
226 //
227 // Electric resistance [E][T][Q^-2]
228 //
229 static constexpr double ohm = volt/ampere;// ohm = 1.60217e-16*(MeV/eplus)/(eplus/ns)
230
231 //
232 // Electric capacitance [Q^2][E^-1]
233 //
234 static constexpr double farad = coulomb/volt;// farad = 6.24150e+24 * eplus/Megavolt
235 static constexpr double millifarad = 1.e-3*farad;
236 static constexpr double microfarad = 1.e-6*farad;
237 static constexpr double nanofarad = 1.e-9*farad;
238 static constexpr double picofarad = 1.e-12*farad;
239
240 //
241 // Magnetic Flux [T][E][Q^-1]
242 //
243 static constexpr double weber = volt*second;// weber = 1000*megavolt*ns
244
245 //
246 // Magnetic Field [T][E][Q^-1][L^-2]
247 //
248 static constexpr double tesla = volt*second/meter2;// tesla =0.001*megavolt*ns/mm2
249
250 static constexpr double gauss = 1.e-4*tesla;
251 static constexpr double kilogauss = 1.e-1*tesla;
252
253 //
254 // Inductance [T^2][E][Q^-2]
255 //
256 static constexpr double henry = weber/ampere;// henry = 1.60217e-7*MeV*(ns/eplus)**2
257
258 //
259 // Temperature
260 //
261 static constexpr double kelvin = 1.;
262
263 //
264 // Amount of substance
265 //
266 static constexpr double mole = 1.;
267
268 //
269 // Activity [T^-1]
270 //
271 static constexpr double becquerel = 1./second ;
272 static constexpr double curie = 3.7e+10 * becquerel;
273 static constexpr double kilobecquerel = 1.e+3*becquerel;
274 static constexpr double megabecquerel = 1.e+6*becquerel;
275 static constexpr double gigabecquerel = 1.e+9*becquerel;
276 static constexpr double millicurie = 1.e-3*curie;
277 static constexpr double microcurie = 1.e-6*curie;
278 static constexpr double Bq = becquerel;
279 static constexpr double kBq = kilobecquerel;
280 static constexpr double MBq = megabecquerel;
281 static constexpr double GBq = gigabecquerel;
282 static constexpr double Ci = curie;
283 static constexpr double mCi = millicurie;
284 static constexpr double uCi = microcurie;
285
286 //
287 // Absorbed dose [L^2][T^-2]
288 //
289 static constexpr double gray = joule/kilogram ;
290 static constexpr double kilogray = 1.e+3*gray;
291 static constexpr double milligray = 1.e-3*gray;
292 static constexpr double microgray = 1.e-6*gray;
293
294 //
295 // Luminous intensity [I]
296 //
297 static constexpr double candela = 1.;
298
299 //
300 // Luminous flux [I]
301 //
302 static constexpr double lumen = candela*steradian;
303
304 //
305 // Illuminance [I][L^-2]
306 //
307 static constexpr double lux = lumen/meter2;
308
309 //
310 // Miscellaneous
311 //
312 static constexpr double perCent = 0.01 ;
313 static constexpr double perThousand = 0.001;
314 static constexpr double perMillion = 0.000001;
315
316} // namespace CLHEP
317
318#endif /* HEP_SYSTEM_OF_UNITS_H */
pascal
#define pascal
Definition: SystemOfUnits.h:206
CLHEP
Definition: DoubConv.h:17
ns
#define ns
Definition: xmlparse.cc:614