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SystemOfUnits.py
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1 # File: AthenaCommon/share/SystemOfUnits.py
2 # Author: Wim Lavrijsen (LBNL, WLavrijsen@lbl.gov)
3 # Created: 01/21/04
4 # Last: 01/21/04
5 
6 # This script is a direct adaptation of CLHEP/Units/SystemOfUnits.h
7 # and the following is the originial CLHEP comment:
8 #
9 # -----
10 # HEP coherent system of Units
11 #
12 # This file has been provided to CLHEP by Geant4 (simulation toolkit for HEP).
13 #
14 # The basic units are :
15 # millimeter (millimeter)
16 # nanosecond (nanosecond)
17 # Mega electron Volt (MeV)
18 # positron charge (eplus)
19 # degree Kelvin (kelvin)
20 # the amount of substance (mole)
21 # luminous intensity (candela)
22 # radian (radian)
23 # steradian (steradian)
24 #
25 # Below is a non exhaustive list of derived and pratical units
26 # (i.e. mostly the SI units).
27 # You can add your own units.
28 #
29 # The SI numerical value of the positron charge is defined here,
30 # as it is needed for conversion factor : positron charge = e_SI (coulomb)
31 #
32 # The others physical constants are defined in the header file :
33 # PhysicalConstants.h
34 #
35 # Authors: M.Maire, S.Giani
36 #
37 # History:
38 #
39 # 06.02.96 Created.
40 # 28.03.96 Added miscellaneous constants.
41 # 05.12.97 E.Tcherniaev: Redefined pascal (to avoid warnings on WinNT)
42 # 20.05.98 names: meter, second, gram, radian, degree
43 # (from Brian.Lasiuk@yale.edu (STAR)). Added luminous units.
44 # 05.08.98 angstrom, picobarn, microsecond, picosecond, petaelectronvolt
45 # 01.03.01 parsec
46 # -----
47 
48 #
49 # Length [L]
50 #
51 millimeter = 1.
52 millimeter2 = millimeter*millimeter
53 millimeter3 = millimeter*millimeter*millimeter
54 
55 centimeter = 10.*millimeter
56 centimeter2 = centimeter*centimeter
57 centimeter3 = centimeter*centimeter*centimeter
58 
59 meter = 1000.*millimeter
60 meter2 = meter*meter
61 meter3 = meter*meter*meter
62 
63 kilometer = 1000.*meter
64 kilometer2 = kilometer*kilometer
65 kilometer3 = kilometer*kilometer*kilometer
66 
67 parsec = 3.0856775807e+16*meter
68 
69 micrometer = 1.e-6 *meter
70 nanometer = 1.e-9 *meter
71 angstrom = 1.e-10*meter
72 fermi = 1.e-15*meter
73 
74 barn = 1.e-28*meter2
75 millibarn = 1.e-3 *barn
76 microbarn = 1.e-6 *barn
77 nanobarn = 1.e-9 *barn
78 picobarn = 1.e-12*barn
79 
80 # symbols
81 mm = millimeter
82 mm2 = millimeter2
83 mm3 = millimeter3
84 
85 cm = centimeter
86 cm2 = centimeter2
87 cm3 = centimeter3
88 
89 m = meter
90 m2 = meter2
91 m3 = meter3
92 
93 km = kilometer
94 km2 = kilometer2
95 km3 = kilometer3
96 
97 pc = parsec
98 
99 #
100 # Angle
101 #
102 radian = 1.
103 milliradian = 1.e-3*radian
104 degree = (3.14159265358979323846/180.0)*radian
105 
106 steradian = 1.
107 
108 # symbols
109 rad = radian
110 mrad = milliradian
111 sr = steradian
112 deg = degree
113 
114 #
115 # Time [T]
116 #
117 nanosecond = 1.
118 second = 1.e+9 *nanosecond
119 millisecond = 1.e-3 *second
120 microsecond = 1.e-6 *second
121 picosecond = 1.e-12*second
122 femtosecond = 1.e-15*second
123 
124 hertz = 1./second
125 kilohertz = 1.e+3*hertz
126 megahertz = 1.e+6*hertz
127 
128 # symbols
129 ns = nanosecond
130 s = second
131 ms = millisecond
132 
133 #
134 # Electric charge [Q]
135 #
136 eplus = 1. # positron charge
137 e_SI = 1.60217733e-19 # positron charge in coulomb
138 coulomb = eplus/e_SI # coulomb = 6.24150 e+18 * eplus
139 
140 #
141 # Energy [E]
142 #
143 megaelectronvolt = 1.
144 electronvolt = 1.e-6*megaelectronvolt
145 kiloelectronvolt = 1.e-3*megaelectronvolt
146 gigaelectronvolt = 1.e+3*megaelectronvolt
147 teraelectronvolt = 1.e+6*megaelectronvolt
148 petaelectronvolt = 1.e+9*megaelectronvolt
149 
150 joule = electronvolt/e_SI # joule = 6.24150 e+12 * MeV
151 
152 # symbols
153 MeV = megaelectronvolt
154 eV = electronvolt
155 keV = kiloelectronvolt
156 GeV = gigaelectronvolt
157 TeV = teraelectronvolt
158 PeV = petaelectronvolt
159 
160 #
161 # Mass [E][T^2][L^-2]
162 #
163 kilogram = joule*second*second/(meter*meter)
164 gram = 1.e-3*kilogram
165 milligram = 1.e-3*gram
166 
167 # symbols
168 kg = kilogram
169 g = gram
170 mg = milligram
171 
172 #
173 # Power [E][T^-1]
174 #
175 watt = joule/second # watt = 6.24150 e+3 * MeV/ns
176 
177 #
178 # Force [E][L^-1]
179 #
180 newton = joule/meter # newton = 6.24150 e+9 * MeV/mm
181 
182 #
183 # Pressure [E][L^-3]
184 #
185 hep_pascal = newton/m2 # pascal = 6.24150 e+3 * MeV/mm3
186 pascal = hep_pascal # a trick to avoid warnings
187 bar = 100000*pascal # bar = 6.24150 e+8 * MeV/mm3
188 atmosphere = 101325*pascal # atm = 6.32420 e+8 * MeV/mm3
189 
190 #
191 # Electric current [Q][T^-1]
192 #
193 ampere = coulomb/second # ampere = 6.24150 e+9 * eplus/ns
194 milliampere = 1.e-3*ampere
195 microampere = 1.e-6*ampere
196 nanoampere = 1.e-9*ampere
197 
198 #
199 # Electric potential [E][Q^-1]
200 #
201 megavolt = megaelectronvolt/eplus
202 kilovolt = 1.e-3*megavolt
203 volt = 1.e-6*megavolt
204 
205 #
206 # Electric resistance [E][T][Q^-2]
207 #
208 ohm = volt/ampere # ohm = 1.60217e-16*(MeV/eplus)/(eplus/ns)
209 
210 #
211 # Electric capacitance [Q^2][E^-1]
212 #
213 farad = coulomb/volt # farad = 6.24150e+24 * eplus/Megavolt
214 millifarad = 1.e-3*farad
215 microfarad = 1.e-6*farad
216 nanofarad = 1.e-9*farad
217 picofarad = 1.e-12*farad
218 
219 #
220 # Magnetic Flux [T][E][Q^-1]
221 #
222 weber = volt*second # weber = 1000*megavolt*ns
223 
224 #
225 # Magnetic Field [T][E][Q^-1][L^-2]
226 #
227 tesla = volt*second/meter2 # tesla =0.001*megavolt*ns/mm2
228 
229 gauss = 1.e-4*tesla
230 kilogauss = 1.e-1*tesla
231 
232 #
233 # Inductance [T^2][E][Q^-2]
234 #
235 henry = weber/ampere # henry = 1.60217e-7*MeV*(ns/eplus)**2
236 
237 #
238 # Temperature
239 #
240 kelvin = 1.
241 
242 #
243 # Amount of substance
244 #
245 mole = 1.
246 
247 #
248 # Activity [T^-1]
249 #
250 becquerel = 1./second
251 curie = 3.7e+10 * becquerel
252 
253 #
254 # Absorbed dose [L^2][T^-2]
255 #
256 gray = joule/kilogram
257 
258 #
259 # Luminous intensity [I]
260 #
261 candela = 1.
262 
263 #
264 # Luminous flux [I]
265 #
266 lumen = candela*steradian
267 
268 #
269 # Illuminance [I][L^-2]
270 #
271 lux = lumen/meter2
272 
273 #
274 # Miscellaneous
275 #
276 perCent = 0.01
277 perThousand = 0.001
278 perMillion = 0.000001