SystemOfUnits.py

# File: AthenaCommon/share/SystemOfUnits.py
# Author: Wim Lavrijsen (LBNL, WLavrijsen@lbl.gov)
# Created: 01/21/04
# Last: 01/21/04

# 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
# -----

#
# Length [L]
#
millimeter  = 1.
millimeter2 = millimeter*millimeter
millimeter3 = millimeter*millimeter*millimeter

centimeter  = 10.*millimeter
centimeter2 = centimeter*centimeter
centimeter3 = centimeter*centimeter*centimeter

meter  = 1000.*millimeter
meter2 = meter*meter
meter3 = meter*meter*meter

kilometer = 1000.*meter
kilometer2 = kilometer*kilometer
kilometer3 = kilometer*kilometer*kilometer

parsec = 3.0856775807e+16*meter

micrometer = 1.e-6 *meter
nanometer  = 1.e-9 *meter
angstrom   = 1.e-10*meter
fermi      = 1.e-15*meter

barn       = 1.e-28*meter2
millibarn  = 1.e-3 *barn
microbarn  = 1.e-6 *barn
nanobarn   = 1.e-9 *barn
picobarn   = 1.e-12*barn

# 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.
milliradian = 1.e-3*radian
degree = (3.14159265358979323846/180.0)*radian

steradian   = 1.

# symbols
rad  = radian
mrad = milliradian
sr   = steradian
deg  = degree

#
# Time [T]
#
nanosecond  = 1.
second      = 1.e+9 *nanosecond
millisecond = 1.e-3 *second
microsecond = 1.e-6 *second
picosecond  = 1.e-12*second
femtosecond = 1.e-15*second

hertz = 1./second
kilohertz = 1.e+3*hertz
megahertz = 1.e+6*hertz

# symbols
ns = nanosecond
s  = second
ms = millisecond

#
# Electric charge [Q]
#
eplus = 1.                                   # positron charge
e_SI  = 1.60217733e-19                       # positron charge in coulomb
coulomb = eplus/e_SI                         # coulomb = 6.24150 e+18 * eplus

#
# Energy [E]
#
megaelectronvolt = 1.
electronvolt     = 1.e-6*megaelectronvolt
kiloelectronvolt = 1.e-3*megaelectronvolt
gigaelectronvolt = 1.e+3*megaelectronvolt
teraelectronvolt = 1.e+6*megaelectronvolt
petaelectronvolt = 1.e+9*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.e-3*kilogram
milligram = 1.e-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.e-3*ampere
microampere = 1.e-6*ampere
nanoampere  = 1.e-9*ampere

#
# Electric potential [E][Q^-1]
#
megavolt = megaelectronvolt/eplus
kilovolt = 1.e-3*megavolt
volt = 1.e-6*megavolt

#
# Electric resistance [E][T][Q^-2]
#
ohm = volt/ampere                            # ohm = 1.60217e-16*(MeV/eplus)/(eplus/ns)

#
# Electric capacitance [Q^2][E^-1]
#
farad = coulomb/volt                         # farad = 6.24150e+24 * eplus/Megavolt
millifarad = 1.e-3*farad
microfarad = 1.e-6*farad
nanofarad = 1.e-9*farad
picofarad = 1.e-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.e-4*tesla
kilogauss = 1.e-1*tesla

#
# Inductance [T^2][E][Q^-2]
#
henry = weber/ampere                         # henry = 1.60217e-7*MeV*(ns/eplus)**2

#
# Temperature
#
kelvin = 1.

#
# Amount of substance
#
mole = 1.

#
# Activity [T^-1]
#
becquerel = 1./second
curie = 3.7e+10 * becquerel

#
# Absorbed dose [L^2][T^-2]
#
gray = joule/kilogram

#
# Luminous intensity [I]
#
candela = 1.

#
# Luminous flux [I]
#
lumen = candela*steradian

#
# Illuminance [I][L^-2]
#
lux = lumen/meter2

#
# Miscellaneous
#
perCent     = 0.01
perThousand = 0.001
perMillion  = 0.000001