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SystemOfUnits.h
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1// -*- C++ -*-
2// $Id:$
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
47namespace CLHEP {
48
49 //
50 // Length [L]
51 //
52 static const double millimeter = 1.;
53 static const double millimeter2 = millimeter*millimeter;
54 static const double millimeter3 = millimeter*millimeter*millimeter;
55
56 static const double centimeter = 10.*millimeter;
57 static const double centimeter2 = centimeter*centimeter;
58 static const double centimeter3 = centimeter*centimeter*centimeter;
59
60 static const double meter = 1000.*millimeter;
61 static const double meter2 = meter*meter;
62 static const double meter3 = meter*meter*meter;
63
64 static const double kilometer = 1000.*meter;
65 static const double kilometer2 = kilometer*kilometer;
66 static const double kilometer3 = kilometer*kilometer*kilometer;
67
68 static const double parsec = 3.0856775807e+16*meter;
69
70 static const double micrometer = 1.e-6 *meter;
71 static const double nanometer = 1.e-9 *meter;
72 static const double angstrom = 1.e-10*meter;
73 static const double fermi = 1.e-15*meter;
74
75 static const double barn = 1.e-28*meter2;
76 static const double millibarn = 1.e-3 *barn;
77 static const double microbarn = 1.e-6 *barn;
78 static const double nanobarn = 1.e-9 *barn;
79 static const double picobarn = 1.e-12*barn;
80
81 // symbols
82 static const double nm = nanometer;
83 static const double um = micrometer;
84
85 static const double mm = millimeter;
86 static const double mm2 = millimeter2;
87 static const double mm3 = millimeter3;
88
89 static const double cm = centimeter;
90 static const double cm2 = centimeter2;
91 static const double cm3 = centimeter3;
92
93 static const double m = meter;
94 static const double m2 = meter2;
95 static const double m3 = meter3;
96
97 static const double km = kilometer;
98 static const double km2 = kilometer2;
99 static const double km3 = kilometer3;
100
101 static const double pc = parsec;
102
103 //
104 // Angle
105 //
106 static const double radian = 1.;
107 static const double milliradian = 1.e-3*radian;
108 static const double degree = (3.14159265358979323846/180.0)*radian;
109
110 static const double steradian = 1.;
111
112 // symbols
113 static const double rad = radian;
114 static const double mrad = milliradian;
115 static const double sr = steradian;
116 static const double deg = degree;
117
118 //
119 // Time [T]
120 //
121 static const double nanosecond = 1.;
122 static const double second = 1.e+9 *nanosecond;
123 static const double millisecond = 1.e-3 *second;
124 static const double microsecond = 1.e-6 *second;
125 static const double picosecond = 1.e-12*second;
126
127 static const double hertz = 1./second;
128 static const double kilohertz = 1.e+3*hertz;
129 static const double megahertz = 1.e+6*hertz;
130
131 // symbols
132 static const double ns = nanosecond;
133 static const double s = second;
134 static const double ms = millisecond;
135
136 //
137 // Electric charge [Q]
138 //
139 static const double eplus = 1. ;// positron charge
140 static const double e_SI = 1.602176487e-19;// positron charge in coulomb
141 static const double coulomb = eplus/e_SI;// coulomb = 6.24150 e+18 * eplus
142
143 //
144 // Energy [E]
145 //
146 static const double megaelectronvolt = 1. ;
147 static const double electronvolt = 1.e-6*megaelectronvolt;
148 static const double kiloelectronvolt = 1.e-3*megaelectronvolt;
149 static const double gigaelectronvolt = 1.e+3*megaelectronvolt;
150 static const double teraelectronvolt = 1.e+6*megaelectronvolt;
151 static const double petaelectronvolt = 1.e+9*megaelectronvolt;
152
153 static const double joule = electronvolt/e_SI;// joule = 6.24150 e+12 * MeV
154
155 // symbols
156 static const double MeV = megaelectronvolt;
157 static const double eV = electronvolt;
158 static const double keV = kiloelectronvolt;
159 static const double GeV = gigaelectronvolt;
160 static const double TeV = teraelectronvolt;
161 static const double PeV = petaelectronvolt;
162
163 //
164 // Mass [E][T^2][L^-2]
165 //
166 static const double kilogram = joule*second*second/(meter*meter);
167 static const double gram = 1.e-3*kilogram;
168 static const double milligram = 1.e-3*gram;
169
170 // symbols
171 static const double kg = kilogram;
172 static const double g = gram;
173 static const double mg = milligram;
174
175 //
176 // Power [E][T^-1]
177 //
178 static const double watt = joule/second;// watt = 6.24150 e+3 * MeV/ns
179
180 //
181 // Force [E][L^-1]
182 //
183 static const double newton = joule/meter;// newton = 6.24150 e+9 * MeV/mm
184
185 //
186 // Pressure [E][L^-3]
187 //
188#define pascal hep_pascal // a trick to avoid warnings
189 static const double hep_pascal = newton/m2; // pascal = 6.24150 e+3 * MeV/mm3
190 static const double bar = 100000*pascal; // bar = 6.24150 e+8 * MeV/mm3
191 static const double atmosphere = 101325*pascal; // atm = 6.32420 e+8 * MeV/mm3
192
193 //
194 // Electric current [Q][T^-1]
195 //
196 static const double ampere = coulomb/second; // ampere = 6.24150 e+9 * eplus/ns
197 static const double milliampere = 1.e-3*ampere;
198 static const double microampere = 1.e-6*ampere;
199 static const double nanoampere = 1.e-9*ampere;
200
201 //
202 // Electric potential [E][Q^-1]
203 //
204 static const double megavolt = megaelectronvolt/eplus;
205 static const double kilovolt = 1.e-3*megavolt;
206 static const double volt = 1.e-6*megavolt;
207
208 //
209 // Electric resistance [E][T][Q^-2]
210 //
211 static const double ohm = volt/ampere;// ohm = 1.60217e-16*(MeV/eplus)/(eplus/ns)
212
213 //
214 // Electric capacitance [Q^2][E^-1]
215 //
216 static const double farad = coulomb/volt;// farad = 6.24150e+24 * eplus/Megavolt
217 static const double millifarad = 1.e-3*farad;
218 static const double microfarad = 1.e-6*farad;
219 static const double nanofarad = 1.e-9*farad;
220 static const double picofarad = 1.e-12*farad;
221
222 //
223 // Magnetic Flux [T][E][Q^-1]
224 //
225 static const double weber = volt*second;// weber = 1000*megavolt*ns
226
227 //
228 // Magnetic Field [T][E][Q^-1][L^-2]
229 //
230 static const double tesla = volt*second/meter2;// tesla =0.001*megavolt*ns/mm2
231
232 static const double gauss = 1.e-4*tesla;
233 static const double kilogauss = 1.e-1*tesla;
234
235 //
236 // Inductance [T^2][E][Q^-2]
237 //
238 static const double henry = weber/ampere;// henry = 1.60217e-7*MeV*(ns/eplus)**2
239
240 //
241 // Temperature
242 //
243 static const double kelvin = 1.;
244
245 //
246 // Amount of substance
247 //
248 static const double mole = 1.;
249
250 //
251 // Activity [T^-1]
252 //
253 static const double becquerel = 1./second ;
254 static const double curie = 3.7e+10 * becquerel;
255
256 //
257 // Absorbed dose [L^2][T^-2]
258 //
259 static const double gray = joule/kilogram ;
260 static const double kilogray = 1.e+3*gray;
261 static const double milligray = 1.e-3*gray;
262 static const double microgray = 1.e-6*gray;
263
264 //
265 // Luminous intensity [I]
266 //
267 static const double candela = 1.;
268
269 //
270 // Luminous flux [I]
271 //
272 static const double lumen = candela*steradian;
273
274 //
275 // Illuminance [I][L^-2]
276 //
277 static const double lux = lumen/meter2;
278
279 //
280 // Miscellaneous
281 //
282 static const double perCent = 0.01 ;
283 static const double perThousand = 0.001;
284 static const double perMillion = 0.000001;
285
286} // namespace CLHEP
287
288#endif /* HEP_SYSTEM_OF_UNITS_H */
pascal
#define pascal
Definition: SystemOfUnits.h:188
CLHEP
Definition: DoubConv.h:17
ns
#define ns
Definition: xmlparse.cc:597