SystemOfUnits.py

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# This script is a direct adaptation of CLHEP/Units/SystemOfUnits.h
# and the following is the originial CLHEP comment:
#
# -----
# HEP coherent system of Units
#
# This file has been provided to CLHEP by Geant4 (simulation toolkit for HEP).
#
# The basic units are :
#               millimeter              (millimeter)
#               nanosecond              (nanosecond)
#               Mega electron Volt      (MeV)
#               positron charge         (eplus)
#               degree Kelvin           (kelvin)
#              the amount of substance (mole)
#              luminous intensity      (candela)
#               radian                  (radian)
#              steradian               (steradian)
#
# Below is a non exhaustive list of derived and pratical units
# (i.e. mostly the SI units).
# You can add your own units.
#
# The SI numerical value of the positron charge is defined here,
# as it is needed for conversion factor : positron charge = e_SI (coulomb)
#
# The others physical constants are defined in the header file :
#                       PhysicalConstants.h
#
# Authors: M.Maire, S.Giani
#
# History:
#
# 06.02.96   Created.
# 28.03.96   Added miscellaneous constants.
# 05.12.97   E.Tcherniaev: Redefined pascal (to avoid warnings on WinNT)
# 20.05.98   names: meter, second, gram, radian, degree
#            (from Brian.Lasiuk@yale.edu (STAR)). Added luminous units.
# 05.08.98   angstrom, picobarn, microsecond, picosecond, petaelectronvolt
# 01.03.01   parsec
# 06.20.25   e_SI
# -----
 
#
# Length [L]
#
millimeter = 1.0
millimeter2 = millimeter * millimeter
millimeter3 = millimeter * millimeter * millimeter
 
centimeter = 10.0 * millimeter
centimeter2 = centimeter * centimeter
centimeter3 = centimeter * centimeter * centimeter
 
meter = 1000.0 * millimeter
meter2 = meter * meter
meter3 = meter * meter * meter
 
kilometer = 1000.0 * meter
kilometer2 = kilometer * kilometer
kilometer3 = kilometer * kilometer * kilometer
 
parsec = 3.0856775807e16 * meter
 
micrometer = 1.0e-6 * meter
nanometer = 1.0e-9 * meter
angstrom = 1.0e-10 * meter
fermi = 1.0e-15 * meter
 
barn = 1.0e-28 * meter2
millibarn = 1.0e-3 * barn
microbarn = 1.0e-6 * barn
nanobarn = 1.0e-9 * barn
picobarn = 1.0e-12 * barn
 
liter = 1.0e3 * centimeter3
L = liter
dL = 1.0e-1 * liter
cL = 1.0e-2 * liter
mL = 1.0e-3 * liter
 
# symbols
mm = millimeter
mm2 = millimeter2
mm3 = millimeter3
 
cm = centimeter
cm2 = centimeter2
cm3 = centimeter3
 
m = meter
m2 = meter2
m3 = meter3
 
km = kilometer
km2 = kilometer2
km3 = kilometer3
 
pc = parsec
 
#
# Angle
#
radian = 1.0
milliradian = 1.0e-3 * radian
degree = (3.14159265358979323846 / 180.0) * radian
 
steradian = 1.0
 
# symbols
rad = radian
mrad = milliradian
sr = steradian
deg = degree
 
#
# Time [T]
#
nanosecond = 1.0
second = 1.0e9 * nanosecond
millisecond = 1.0e-3 * second
microsecond = 1.0e-6 * second
picosecond = 1.0e-12 * second
femtosecond = 1.0e-15 * second
 
hertz = 1.0 / second
kilohertz = 1.0e3 * hertz
megahertz = 1.0e6 * hertz
 
# symbols
ns = nanosecond
s = second
ms = millisecond
us = microsecond
ps = picosecond
 
#
# Electric charge [Q]
#
eplus = 1.0  # positron charge
e_SI = 1.602176634e-19  # positron charge in coulomb
coulomb = eplus / e_SI  # coulomb = 6.24150 e+18 * eplus
 
#
# Energy [E]
#
megaelectronvolt = 1.0
electronvolt = 1.0e-6 * megaelectronvolt
kiloelectronvolt = 1.0e-3 * megaelectronvolt
gigaelectronvolt = 1.0e3 * megaelectronvolt
teraelectronvolt = 1.0e6 * megaelectronvolt
petaelectronvolt = 1.0e9 * megaelectronvolt
 
joule = electronvolt / e_SI  # joule = 6.24150 e+12 * MeV
 
# symbols
MeV = megaelectronvolt
eV = electronvolt
keV = kiloelectronvolt
GeV = gigaelectronvolt
TeV = teraelectronvolt
PeV = petaelectronvolt
 
#
# Mass [E][T^2][L^-2]
#
kilogram = joule * second * second / (meter * meter)
gram = 1.0e-3 * kilogram
milligram = 1.0e-3 * gram
 
# symbols
kg = kilogram
g = gram
mg = milligram
 
#
# Power [E][T^-1]
#
watt = joule / second  # watt = 6.24150 e+3 * MeV/ns
 
#
# Force [E][L^-1]
#
newton = joule / meter  # newton = 6.24150 e+9 * MeV/mm
 
#
# Pressure [E][L^-3]
#
hep_pascal = newton / m2  # pascal = 6.24150 e+3 * MeV/mm3
pascal = hep_pascal  # a trick to avoid warnings
bar = 100000 * pascal  # bar    = 6.24150 e+8 * MeV/mm3
atmosphere = 101325 * pascal  # atm    = 6.32420 e+8 * MeV/mm3
 
#
# Electric current [Q][T^-1]
#
ampere = coulomb / second  # ampere = 6.24150 e+9 * eplus/ns
milliampere = 1.0e-3 * ampere
microampere = 1.0e-6 * ampere
nanoampere = 1.0e-9 * ampere
 
#
# Electric potential [E][Q^-1]
#
megavolt = megaelectronvolt / eplus
kilovolt = 1.0e-3 * megavolt
volt = 1.0e-6 * megavolt
 
#
# Electric resistance [E][T][Q^-2]
#
# ohm = 1.60217e-16*(MeV/eplus)/(eplus/ns)
ohm = volt / ampere
 
#
# Electric capacitance [Q^2][E^-1]
#
# farad = 6.24150e+24 * eplus/Megavolt
farad = coulomb / volt
millifarad = 1.0e-3 * farad
microfarad = 1.0e-6 * farad
nanofarad = 1.0e-9 * farad
picofarad = 1.0e-12 * farad
 
#
# Magnetic Flux [T][E][Q^-1]
#
weber = volt * second  # weber = 1000*megavolt*ns
 
#
# Magnetic Field [T][E][Q^-1][L^-2]
#
tesla = volt * second / meter2  # tesla =0.001*megavolt*ns/mm2
 
gauss = 1.0e-4 * tesla
kilogauss = 1.0e-1 * tesla
 
#
# Inductance [T^2][E][Q^-2]
#
# henry = 1.60217e-7*MeV*(ns/eplus)**2
henry = weber / ampere
 
#
# Temperature
#
kelvin = 1.0
 
#
# Amount of substance
#
mole = 1.0
 
#
# Activity [T^-1]
#
becquerel = 1.0 / second
curie = 3.7e10 * becquerel
kilobecquerel = 1.0e3 * becquerel
megabecquerel = 1.0e6 * becquerel
gigabecquerel = 1.0e9 * becquerel
millicurie = 1.0e-3 * curie
microcurie = 1.0e-6 * curie
Bq = becquerel
kBq = kilobecquerel
MBq = megabecquerel
GBq = gigabecquerel
Ci = curie
mCi = millicurie
uCi = microcurie
 
#
# Absorbed dose [L^2][T^-2]
#
gray = joule / kilogram
kilogray = 1.0e3 * gray
milligray = 1.0e-3 * gray
microgray = 1.0e-6 * gray
 
#
# Luminous intensity [I]
#
candela = 1.0
 
#
# Luminous flux [I]
#
lumen = candela * steradian
 
#
# Illuminance [I][L^-2]
#
lux = lumen / meter2
 
#
# Miscellaneous
#
perCent = 0.01
perThousand = 0.001
perMillion = 0.000001