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Vector/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 
49 namespace 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
304 using namespace CLHEP;
305 #endif
306 
307 #endif /* HEP_SYSTEM_OF_UNITS_H */