CLHEPSystemOfUnits.h

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// author: Jonas Rademacker (Jonas.Rademacker@bristol.ac.uk)
// status:  Mon 9 Feb 2009 19:17:56 GMT
// -*- C++ -*-
// ----------------------------------------------------------------------
// 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    

#ifndef HEP_SYSTEM_OF_UNITS_H
#define HEP_SYSTEM_OF_UNITS_H

// 
// Length [L]
//
static const double millimeter  = 1.;                        
static const double millimeter2 = millimeter*millimeter;
static const double millimeter3 = millimeter*millimeter*millimeter;

static const double centimeter  = 10.*millimeter;   
static const double centimeter2 = centimeter*centimeter;
static const double centimeter3 = centimeter*centimeter*centimeter;

static const double meter  = 1000.*millimeter;                  
static const double meter2 = meter*meter;
static const double meter3 = meter*meter*meter;

static const double kilometer = 1000.*meter;                   
static const double kilometer2 = kilometer*kilometer;
static const double kilometer3 = kilometer*kilometer*kilometer;

static const double parsec = 3.0856775807e+16*meter;

static const double micrometer = 1.e-6 *meter;             
static const double  nanometer = 1.e-9 *meter;
static const double  angstrom  = 1.e-10*meter;
static const double  fermi     = 1.e-15*meter;

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

// symbols
static const double mm  = millimeter;                        
static const double mm2 = millimeter2;
static const double mm3 = millimeter3;

static const double cm  = centimeter;   
static const double cm2 = centimeter2;
static const double cm3 = centimeter3;

static const double m  = meter;                  
static const double m2 = meter2;
static const double m3 = meter3;

static const double km  = kilometer;                   
static const double km2 = kilometer2;
static const double km3 = kilometer3;

static const double pc = parsec;

//
// Angle
//
static const double radian      = 1.;                  
static const double milliradian = 1.e-3*radian;
static const double degree = (3.14159265358979323846/180.0)*radian;

static const double   steradian = 1.;
    
// symbols
static const double rad  = radian;  
static const double mrad = milliradian;
static const double sr   = steradian;
static const double deg  = degree;

//
// Time [T]
//
static const double nanosecond  = 1.;
static const double second      = 1.e+9 *nanosecond;
static const double millisecond = 1.e-3 *second;
static const double microsecond = 1.e-6 *second;
static const double  picosecond = 1.e-12*second;

static const double hertz = 1./second;
static const double kilohertz = 1.e+3*hertz;
static const double megahertz = 1.e+6*hertz;

// symbols
static const double ns = nanosecond;            
static const double  s = second;
static const double ms = millisecond;

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

//
// Energy [E]
//
static const double megaelectronvolt = 1. ;
static const double     electronvolt = 1.e-6*megaelectronvolt;
static const double kiloelectronvolt = 1.e-3*megaelectronvolt;
static const double gigaelectronvolt = 1.e+3*megaelectronvolt;
static const double teraelectronvolt = 1.e+6*megaelectronvolt;
static const double petaelectronvolt = 1.e+9*megaelectronvolt;

static const double joule = electronvolt/e_SI;  // joule = 6.24150 e+12 * MeV

// symbols
static const double MeV = megaelectronvolt;
static const double  eV = electronvolt;
static const double keV = kiloelectronvolt;
static const double GeV = gigaelectronvolt;
static const double TeV = teraelectronvolt;
static const double PeV = petaelectronvolt;

//
// Mass [E][T^2][L^-2]
//
static const double  kilogram = joule*second*second/(meter*meter);   
static const double      gram = 1.e-3*kilogram;
static const double milligram = 1.e-3*gram;

// symbols
static const double  kg = kilogram;
static const double   g = gram;
static const double  mg = milligram;

//
// Power [E][T^-1]
//
static const double watt = joule/second;    // watt = 6.24150 e+3 * MeV/ns

//
// Force [E][L^-1]
//
static const double newton = joule/meter;   // newton = 6.24150 e+9 * MeV/mm

//
// Pressure [E][L^-3]
//
#ifndef __CINT__
#define pascal hep_pascal                          // a trick to avoid warnings 
static const double hep_pascal = newton/m2;    // pascal = 6.24150 e+3 * MeV/mm3
#else
static const double hep_pascal = newton/m2;    // pascal = 6.24150 e+3 * MeV/mm3
static const double pascal = hep_pascal;
#endif

static const double bar        = 100000*pascal; // bar    = 6.24150 e+8 * MeV/mm3
static const double atmosphere = 101325*pascal; // atm    = 6.32420 e+8 * MeV/mm3

//
// Electric current [Q][T^-1]
//
static const double      ampere = coulomb/second; // ampere = 6.24150 e+9 * eplus/ns
static const double milliampere = 1.e-3*ampere;
static const double microampere = 1.e-6*ampere;
static const double  nanoampere = 1.e-9*ampere;

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

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

//
// Electric capacitance [Q^2][E^-1]
//
static const double farad = coulomb/volt;   // farad = 6.24150e+24 * eplus/Megavolt
static const double millifarad = 1.e-3*farad;
static const double microfarad = 1.e-6*farad;
static const double  nanofarad = 1.e-9*farad;
static const double  picofarad = 1.e-12*farad;

//
// Magnetic Flux [T][E][Q^-1]
//
static const double weber = volt*second;    // weber = 1000*megavolt*ns

//
// Magnetic Field [T][E][Q^-1][L^-2]
//
static const double tesla     = volt*second/meter2; // tesla =0.001*megavolt*ns/mm2

static const double gauss     = 1.e-4*tesla;
static const double kilogauss = 1.e-1*tesla;

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

//
// Temperature
//
static const double kelvin = 1.;

//
// Amount of substance
//
static const double mole = 1.;

//
// Activity [T^-1]
//
static const double becquerel = 1./second ;
static const double curie = 3.7e+10 * becquerel;

//
// Absorbed dose [L^2][T^-2]
//
static const double gray = joule/kilogram ;

//
// Luminous intensity [I]
//
static const double candela = 1.;

//
// Luminous flux [I]
//
static const double lumen = candela*steradian;

//
// Illuminance [I][L^-2]
//
static const double lux = lumen/meter2;

//
// Miscellaneous
//
static const double perCent     = 0.01 ;
static const double perThousand = 0.001;
static const double perMillion  = 0.000001;

#endif /* HEP_SYSTEM_OF_UNITS_H */