G4SIunits.hh

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//
// G4SIunits
//
// Description:
//
// This file is a modified version of CLHEP SystemOfUnits.h
// It is provided for checking the overall 'units coherence' in Geant4.
// The basic units are those of the International System:
//
//          meter
//          second
//          kilogram
//          ampere
//          degree kelvin
//      the amount of substance (mole)
//      luminous intensity      (candela)
//          radian
//          steradian
//
// 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 CLHEP header file
// for PhysicalConstants.
 
// Authors: M.Maire, S.Giani - 10.03.1999
// --------------------------------------------------------------------
#ifndef SI_SYSTEM_OF_UNITS_HH
#define SI_SYSTEM_OF_UNITS_HH 1
 
static constexpr double pi     = 3.14159265358979323846;
static constexpr double twopi  = 2 * pi;
static constexpr double halfpi = pi / 2;
static constexpr double pi2    = pi * pi;
//
// Length [L]
//
static constexpr double meter  = 1.;
static constexpr double meter2 = meter * meter;
static constexpr double meter3 = meter * meter * meter;
 
static constexpr double millimeter  = 0.001 * meter;
static constexpr double millimeter2 = millimeter * millimeter;
static constexpr double millimeter3 = millimeter * millimeter * millimeter;
 
static constexpr double centimeter  = 10. * millimeter;
static constexpr double centimeter2 = centimeter * centimeter;
static constexpr double centimeter3 = centimeter * centimeter * centimeter;
 
static constexpr double kilometer  = 1000. * meter;
static constexpr double kilometer2 = kilometer * kilometer;
static constexpr double kilometer3 = kilometer * kilometer * kilometer;
 
static constexpr double parsec = 3.0856775807e+16 * meter;
 
static constexpr double micrometer = 1.e-6 * meter;
static constexpr double nanometer  = 1.e-9 * meter;
static constexpr double angstrom   = 1.e-10 * meter;
static constexpr double fermi      = 1.e-15 * meter;
 
static constexpr double barn      = 1.e-28 * meter2;
static constexpr double millibarn = 1.e-3 * barn;
static constexpr double microbarn = 1.e-6 * barn;
static constexpr double nanobarn  = 1.e-9 * barn;
static constexpr double picobarn  = 1.e-12 * barn;
 
// symbols
static constexpr double nm = nanometer;
static constexpr double um = micrometer;
 
static constexpr double mm  = millimeter;
static constexpr double mm2 = millimeter2;
static constexpr double mm3 = millimeter3;
 
static constexpr double cm  = centimeter;
static constexpr double cm2 = centimeter2;
static constexpr double cm3 = centimeter3;
 
static constexpr double liter = 1.e+3 * cm3;
static constexpr double L     = liter;
static constexpr double dL    = 1.e-1 * liter;
static constexpr double cL    = 1.e-2 * liter;
static constexpr double mL    = 1.e-3 * liter;
 
static constexpr double m  = meter;
static constexpr double m2 = meter2;
static constexpr double m3 = meter3;
 
static constexpr double km  = kilometer;
static constexpr double km2 = kilometer2;
static constexpr double km3 = kilometer3;
 
static constexpr double pc = parsec;
 
//
// Angle
//
static constexpr double radian      = 1.;
static constexpr double milliradian = 1.e-3 * radian;
static constexpr double degree      = (pi / 180.0) * radian;
 
static constexpr double steradian = 1.;
 
// symbols
static constexpr double rad  = radian;
static constexpr double mrad = milliradian;
static constexpr double sr   = steradian;
static constexpr double deg  = degree;
 
//
// Time [T]
//
static constexpr double second      = 1.;
static constexpr double nanosecond  = 1.e-9 * second;
static constexpr double millisecond = 1.e-3 * second;
static constexpr double microsecond = 1.e-6 * second;
static constexpr double picosecond  = 1.e-12 * second;
 
static constexpr double minute = 60*second;
static constexpr double hour   = 60*minute;
static constexpr double day    = 24*hour;
static constexpr double year   = 365*day;  
 
static constexpr double hertz     = 1. / second;
static constexpr double kilohertz = 1.e+3 * hertz;
static constexpr double megahertz = 1.e+6 * hertz;
 
// symbols
static constexpr double ns = nanosecond;
static constexpr double s  = second;
static constexpr double ms = millisecond;
static constexpr double us = microsecond;
static constexpr double ps = picosecond;
 
//
// Mass [E][T^2][L^-2]
//
static constexpr double kilogram  = 1.;
static constexpr double gram      = 1.e-3 * kilogram;
static constexpr double milligram = 1.e-3 * gram;
 
// symbols
static constexpr double kg = kilogram;
static constexpr double g  = gram;
static constexpr double mg = milligram;
 
//
// Electric current [Q][T^-1]
//
static constexpr double ampere      = 1.;
static constexpr double milliampere = 1.e-3 * ampere;
static constexpr double microampere = 1.e-6 * ampere;
static constexpr double nanoampere  = 1.e-9 * ampere;
 
//
// Electric charge [Q]
//
static constexpr double coulomb = ampere * second;
static constexpr double e_SI  = 1.602176634e-19;  // positron charge in coulomb
static constexpr double eplus = e_SI * coulomb;   // positron charge
 
//
// Energy [E]
//
static constexpr double joule = kg * m * m / (s * s);
 
static constexpr double electronvolt     = e_SI * joule;
static constexpr double kiloelectronvolt = 1.e+3 * electronvolt;
static constexpr double megaelectronvolt = 1.e+6 * electronvolt;
static constexpr double gigaelectronvolt = 1.e+9 * electronvolt;
static constexpr double teraelectronvolt = 1.e+12 * electronvolt;
static constexpr double petaelectronvolt = 1.e+15 * electronvolt;
static constexpr double millielectronvolt = 1.e-3 * electronvolt;  
 
// symbols
static constexpr double MeV = megaelectronvolt;
static constexpr double eV  = electronvolt;
static constexpr double keV = kiloelectronvolt;
static constexpr double GeV = gigaelectronvolt;
static constexpr double TeV = teraelectronvolt;
static constexpr double PeV = petaelectronvolt;
 
//
// Power [E][T^-1]
//
static constexpr double watt = joule / second;  // watt = 6.24150 e+3 * MeV/ns
 
//
// Force [E][L^-1]
//
static constexpr double newton =
  joule / meter;  // newton = 6.24150 e+9 * MeV/mm
 
//
// Pressure [E][L^-3]
//
#define pascal hep_pascal  // a trick to avoid warnings
static constexpr double hep_pascal =
  newton / m2;  // pascal = 6.24150 e+3 * MeV/mm3
static constexpr double bar = 100000 * pascal;  // bar = 6.24150 e+8 * MeV/mm3
static constexpr double atmosphere =
  101325 * pascal;  // atm = 6.32420 e+8 * MeV/mm3
 
//
// Electric potential [E][Q^-1]
//
static constexpr double megavolt = megaelectronvolt / eplus;
static constexpr double kilovolt = 1.e-3 * megavolt;
static constexpr double volt     = 1.e-6 * megavolt;
 
//
// Electric resistance [E][T][Q^-2]
//
static constexpr double ohm =
  volt / ampere;  // ohm = 1.60217e-16*(MeV/eplus)/(eplus/ns)
 
//
// Electric capacitance [Q^2][E^-1]
//
static constexpr double farad =
  coulomb / volt;  // farad = 6.24150e+24 * eplus/Megavolt
static constexpr double millifarad = 1.e-3 * farad;
static constexpr double microfarad = 1.e-6 * farad;
static constexpr double nanofarad  = 1.e-9 * farad;
static constexpr double picofarad  = 1.e-12 * farad;
 
//
// Magnetic Flux [T][E][Q^-1]
//
static constexpr double weber = volt * second;  // weber = 1000*megavolt*ns
 
//
// Magnetic Field [T][E][Q^-1][L^-2]
//
static constexpr double tesla =
  volt * second / meter2;  // tesla =0.001*megavolt*ns/mm2
 
static constexpr double gauss     = 1.e-4 * tesla;
static constexpr double kilogauss = 1.e-1 * tesla;
 
//
// Inductance [T^2][E][Q^-2]
//
static constexpr double henry =
  weber / ampere;  // henry = 1.60217e-7*MeV*(ns/eplus)**2
 
//
// Temperature
//
static constexpr double kelvin = 1.;
 
//
// Amount of substance
//
static constexpr double mole = 1.;
 
//
// Activity [T^-1]
//
static constexpr double becquerel     = 1. / second;
static constexpr double curie         = 3.7e+10 * becquerel;
static constexpr double kilobecquerel = 1.e+3 * becquerel;
static constexpr double megabecquerel = 1.e+6 * becquerel;
static constexpr double gigabecquerel = 1.e+9 * becquerel;
static constexpr double millicurie    = 1.e-3 * curie;
static constexpr double microcurie    = 1.e-6 * curie;
static constexpr double Bq            = becquerel;
static constexpr double kBq           = kilobecquerel;
static constexpr double MBq           = megabecquerel;
static constexpr double GBq           = gigabecquerel;
static constexpr double Ci            = curie;
static constexpr double mCi           = millicurie;
static constexpr double uCi           = microcurie;
 
//
// Absorbed dose [L^2][T^-2]
//
static constexpr double gray      = joule / kilogram;
static constexpr double kilogray  = 1.e+3 * gray;
static constexpr double milligray = 1.e-3 * gray;
static constexpr double microgray = 1.e-6 * gray;
 
//
// Luminous intensity [I]
//
static constexpr double candela = 1.;
 
//
// Luminous flux [I]
//
static constexpr double lumen = candela * steradian;
 
//
// Illuminance [I][L^-2]
//
static constexpr double lux = lumen / meter2;
 
//
// Miscellaneous
//
static constexpr double perCent     = 0.01;
static constexpr double perThousand = 0.001;
static constexpr double perMillion  = 0.000001;
 
#endif