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RandomObjects/CLHEP/Units/SystemOfUnits.h
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1// -*- C++ -*-
2// $Id: SystemOfUnits.h,v 1.4 2010/06/16 17:12:28 garren Exp $
3// ----------------------------------------------------------------------
4// HEP coherent system of Units
5//
6// This file has been provided to CLHEP by Geant4 (simulation toolkit for HEP).
7//
8// The basic units are :
9// millimeter (millimeter)
10// nanosecond (nanosecond)
11// Mega electron Volt (MeV)
12// positron charge (eplus)
13// degree Kelvin (kelvin)
14// the amount of substance (mole)
15// luminous intensity (candela)
16// radian (radian)
17// steradian (steradian)
18//
19// Below is a non exhaustive list of derived and pratical units
20// (i.e. mostly the SI units).
21// You can add your own units.
22//
23// The SI numerical value of the positron charge is defined here,
24// as it is needed for conversion factor : positron charge = e_SI (coulomb)
25//
26// The others physical constants are defined in the header file :
27//PhysicalConstants.h
28//
29// Authors: M.Maire, S.Giani
30//
31// History:
32//
33// 06.02.96 Created.
34// 28.03.96 Added miscellaneous constants.
35// 05.12.97 E.Tcherniaev: Redefined pascal (to avoid warnings on WinNT)
36// 20.05.98 names: meter, second, gram, radian, degree
37// (from Brian.Lasiuk@yale.edu (STAR)). Added luminous units.
38// 05.08.98 angstrom, picobarn, microsecond, picosecond, petaelectronvolt
39// 01.03.01 parsec
40// 31.01.06 kilogray, milligray, microgray
41// 29.04.08 use PDG 2006 value of e_SI
42// 03.11.08 use PDG 2008 value of e_SI
43
44#ifndef HEP_SYSTEM_OF_UNITS_H
45#define HEP_SYSTEM_OF_UNITS_H
46
47#include "CLHEP/Units/defs.h"
48
49namespace CLHEP {
50
51 //
52 // Length [L]
53 //
54 static const double millimeter = 1.;
55 static const double millimeter2 = millimeter*millimeter;
56 static const double millimeter3 = millimeter*millimeter*millimeter;
57
58 static const double centimeter = 10.*millimeter;
59 static const double centimeter2 = centimeter*centimeter;
60 static const double centimeter3 = centimeter*centimeter*centimeter;
61
62 static const double meter = 1000.*millimeter;
63 static const double meter2 = meter*meter;
64 static const double meter3 = meter*meter*meter;
65
66 static const double kilometer = 1000.*meter;
67 static const double kilometer2 = kilometer*kilometer;
68 static const double kilometer3 = kilometer*kilometer*kilometer;
69
70 static const double parsec = 3.0856775807e+16*meter;
71
72 static const double micrometer = 1.e-6 *meter;
73 static const double nanometer = 1.e-9 *meter;
74 static const double angstrom = 1.e-10*meter;
75 static const double fermi = 1.e-15*meter;
76
77 static const double barn = 1.e-28*meter2;
78 static const double millibarn = 1.e-3 *barn;
79 static const double microbarn = 1.e-6 *barn;
80 static const double nanobarn = 1.e-9 *barn;
81 static const double picobarn = 1.e-12*barn;
82
83 // symbols
84 static const double nm = nanometer;
85 static const double um = micrometer;
86
87 static const double mm = millimeter;
88 static const double mm2 = millimeter2;
89 static const double mm3 = millimeter3;
90
91 static const double cm = centimeter;
92 static const double cm2 = centimeter2;
93 static const double cm3 = centimeter3;
94
95 static const double m = meter;
96 static const double m2 = meter2;
97 static const double m3 = meter3;
98
99 static const double km = kilometer;
100 static const double km2 = kilometer2;
101 static const double km3 = kilometer3;
102
103 static const double pc = parsec;
104
105 //
106 // Angle
107 //
108 static const double radian = 1.;
109 static const double milliradian = 1.e-3*radian;
110 static const double degree = (3.14159265358979323846/180.0)*radian;
111
112 static const double steradian = 1.;
113
114 // symbols
115 static const double rad = radian;
116 static const double mrad = milliradian;
117 static const double sr = steradian;
118 static const double deg = degree;
119
120 //
121 // Time [T]
122 //
123 static const double nanosecond = 1.;
124 static const double second = 1.e+9 *nanosecond;
125 static const double millisecond = 1.e-3 *second;
126 static const double microsecond = 1.e-6 *second;
127 static const double picosecond = 1.e-12*second;
128
129 static const double hertz = 1./second;
130 static const double kilohertz = 1.e+3*hertz;
131 static const double megahertz = 1.e+6*hertz;
132
133 // symbols
134 static const double ns = nanosecond;
135 static const double s = second;
136 static const double ms = millisecond;
137
138 //
139 // Electric charge [Q]
140 //
141 static const double eplus = 1. ;// positron charge
142 static const double e_SI = 1.602176487e-19;// positron charge in coulomb
143 static const double coulomb = eplus/e_SI;// coulomb = 6.24150 e+18 * eplus
144
145 //
146 // Energy [E]
147 //
148 static const double megaelectronvolt = 1. ;
149 static const double electronvolt = 1.e-6*megaelectronvolt;
150 static const double kiloelectronvolt = 1.e-3*megaelectronvolt;
151 static const double gigaelectronvolt = 1.e+3*megaelectronvolt;
152 static const double teraelectronvolt = 1.e+6*megaelectronvolt;
153 static const double petaelectronvolt = 1.e+9*megaelectronvolt;
154
155 static const double joule = electronvolt/e_SI;// joule = 6.24150 e+12 * MeV
156
157 // symbols
158 static const double MeV = megaelectronvolt;
159 static const double eV = electronvolt;
160 static const double keV = kiloelectronvolt;
161 static const double GeV = gigaelectronvolt;
162 static const double TeV = teraelectronvolt;
163 static const double PeV = petaelectronvolt;
164
165 //
166 // Mass [E][T^2][L^-2]
167 //
168 static const double kilogram = joule*second*second/(meter*meter);
169 static const double gram = 1.e-3*kilogram;
170 static const double milligram = 1.e-3*gram;
171
172 // symbols
173 static const double kg = kilogram;
174 static const double g = gram;
175 static const double mg = milligram;
176
177 //
178 // Power [E][T^-1]
179 //
180 static const double watt = joule/second;// watt = 6.24150 e+3 * MeV/ns
181
182 //
183 // Force [E][L^-1]
184 //
185 static const double newton = joule/meter;// newton = 6.24150 e+9 * MeV/mm
186
187 //
188 // Pressure [E][L^-3]
189 //
190#define pascal hep_pascal // a trick to avoid warnings
191 static const double hep_pascal = newton/m2; // pascal = 6.24150 e+3 * MeV/mm3
192 static const double bar = 100000*pascal; // bar = 6.24150 e+8 * MeV/mm3
193 static const double atmosphere = 101325*pascal; // atm = 6.32420 e+8 * MeV/mm3
194
195 //
196 // Electric current [Q][T^-1]
197 //
198 static const double ampere = coulomb/second; // ampere = 6.24150 e+9 * eplus/ns
199 static const double milliampere = 1.e-3*ampere;
200 static const double microampere = 1.e-6*ampere;
201 static const double nanoampere = 1.e-9*ampere;
202
203 //
204 // Electric potential [E][Q^-1]
205 //
206 static const double megavolt = megaelectronvolt/eplus;
207 static const double kilovolt = 1.e-3*megavolt;
208 static const double volt = 1.e-6*megavolt;
209
210 //
211 // Electric resistance [E][T][Q^-2]
212 //
213 static const double ohm = volt/ampere;// ohm = 1.60217e-16*(MeV/eplus)/(eplus/ns)
214
215 //
216 // Electric capacitance [Q^2][E^-1]
217 //
218 static const double farad = coulomb/volt;// farad = 6.24150e+24 * eplus/Megavolt
219 static const double millifarad = 1.e-3*farad;
220 static const double microfarad = 1.e-6*farad;
221 static const double nanofarad = 1.e-9*farad;
222 static const double picofarad = 1.e-12*farad;
223
224 //
225 // Magnetic Flux [T][E][Q^-1]
226 //
227 static const double weber = volt*second;// weber = 1000*megavolt*ns
228
229 //
230 // Magnetic Field [T][E][Q^-1][L^-2]
231 //
232 static const double tesla = volt*second/meter2;// tesla =0.001*megavolt*ns/mm2
233
234 static const double gauss = 1.e-4*tesla;
235 static const double kilogauss = 1.e-1*tesla;
236
237 //
238 // Inductance [T^2][E][Q^-2]
239 //
240 static const double henry = weber/ampere;// henry = 1.60217e-7*MeV*(ns/eplus)**2
241
242 //
243 // Temperature
244 //
245 static const double kelvin = 1.;
246
247 //
248 // Amount of substance
249 //
250 static const double mole = 1.;
251
252 //
253 // Activity [T^-1]
254 //
255 static const double becquerel = 1./second ;
256 static const double curie = 3.7e+10 * becquerel;
257 static const double kilobecquerel = 1.e+3*becquerel;
258 static const double megabecquerel = 1.e+6*becquerel;
259 static const double gigabecquerel = 1.e+9*becquerel;
260 static const double millicurie = 1.e-3*curie;
261 static const double microcurie = 1.e-6*curie;
262 static const double Bq = becquerel;
263 static const double kBq = kilobecquerel;
264 static const double MBq = megabecquerel;
265 static const double GBq = gigabecquerel;
266 static const double Ci = curie;
267 static const double mCi = millicurie;
268 static const double uCi = microcurie;
269
270 //
271 // Absorbed dose [L^2][T^-2]
272 //
273 static const double gray = joule/kilogram ;
274 static const double kilogray = 1.e+3*gray;
275 static const double milligray = 1.e-3*gray;
276 static const double microgray = 1.e-6*gray;
277
278 //
279 // Luminous intensity [I]
280 //
281 static const double candela = 1.;
282
283 //
284 // Luminous flux [I]
285 //
286 static const double lumen = candela*steradian;
287
288 //
289 // Illuminance [I][L^-2]
290 //
291 static const double lux = lumen/meter2;
292
293 //
294 // Miscellaneous
295 //
296 static const double perCent = 0.01 ;
297 static const double perThousand = 0.001;
298 static const double perMillion = 0.000001;
299
300} // namespace CLHEP
301
302#ifdef ENABLE_BACKWARDS_COMPATIBILITY
303// backwards compatibility will be enabled ONLY in CLHEP 1.9
304using namespace CLHEP;
305#endif
306
307#endif /* HEP_SYSTEM_OF_UNITS_H */