Variables
TDatabasePDG *	pdgBase = TDatabasePDG::Instance()

const double	mass_proton = pdgBase->GetParticle(2212)->Mass()*units::GeV

const double	mass_neutron = pdgBase->GetParticle(2112)->Mass()*units::GeV

const double	mass_electron = pdgBase->GetParticle(11)->Mass()*units::GeV

const double	mass_muon = pdgBase->GetParticle(13)->Mass()*units::GeV

const double	mass_pion_zero = pdgBase->GetParticle(111)->Mass()*units::GeV

const double	mass_pion_charged = pdgBase->GetParticle(211)->Mass()*units::GeV

const double	mass_kaon_zero = pdgBase->GetParticle(311)->Mass()*units::GeV

const double	mass_kaon_charged = pdgBase->GetParticle(321)->Mass()*units::GeV

const double	pi = 3.14159265358979323846

const double	twopi = 2*pi

const double	halfpi = pi/2

const double	pi2 = pi*pi

const double	Avogadro = 6.0221367e+23/mole

const double	c_light = 2.99792458e+8 * meter/second

const double	c_squared = c_light * c_light

const double	h_Planck = 6.6260755e-34 * joule*second

const double	hbar_Planck = h_Planck/twopi

const double	hbarc = hbar_Planck * c_light

const double	hbarc_squared = hbarc * hbarc

const double	electron_charge = - eplus

const double	e_squared = eplus * eplus

const double	electron_mass_c2 = 0.51099906 * MeV

const double	proton_mass_c2 = 938.27231 * MeV

const double	neutron_mass_c2 = 939.56563 * MeV

const double	amu_c2 = 931.49432 * MeV

const double	amu = amu_c2/c_squared

const double	mu0 = 4pi1.e-7 * henry/meter

const double	epsilon0 = 1./(c_squared*mu0)

const double	elm_coupling = e_squared/(4piepsilon0)

const double	fine_structure_const = elm_coupling/hbarc

const double	classic_electr_radius = elm_coupling/electron_mass_c2

const double	electron_Compton_length = hbarc/electron_mass_c2

const double	Bohr_radius = electron_Compton_length/fine_structure_const

const double	alpha_rcl2

const double	twopi_mc2_rcl2

const double	k_Boltzmann = 8.617385e-11 * MeV/kelvin

const double	STP_Temperature = 273.15*kelvin

const double	STP_Pressure = 1.*atmosphere

const double	kGasThreshold = 10.*milligram/centimeter3

const double	universe_mean_density = 1.e-25*gram/centimeter3

const double	yotta = 1.e+24

const double	zetta = 1.e+21

const double	exa = 1.e+18

const double	peta = 1.e+15

const double	tera = 1.e+12

const double	giga = 1.e+9

const double	mega = 1.e+6

const double	kilo = 1.e+3

const double	hecto = 100

const double	deca = 10

const double	deci = 0.1

const double	centi = 0.01

const double	milli = 1.e-3

const double	micro = 1.e-6

const double	nano = 1.e-9

const double	pico = 1.e-12

const double	femto = 1.e-15

const double	atto = 1.e-18

const double	zepto = 1.e-21

const double	yocto = 1.e-24

const double	millimeter = 1.

const double	millimeter2 = millimeter*millimeter

const double	millimeter3 = millimetermillimetermillimeter

const double	centimeter = 10.*millimeter

const double	centimeter2 = centimeter*centimeter

const double	centimeter3 = centimetercentimetercentimeter

const double	meter = 1000.*millimeter

const double	meter2 = meter*meter

const double	meter3 = metermetermeter

const double	kilometer = kilo*meter

const double	kilometer2 = kilometer*kilometer

const double	kilometer3 = kilometerkilometerkilometer

const double	micrometer = micro*meter

const double	nanometer = nano*meter

const double	angstrom = 1.e-10*meter

const double	fermi = femto*meter

const double	barn = 1.e-28*meter2

const double	millibarn = milli*barn

const double	microbarn = micro*barn

const double	nanobarn = nano*barn

const double	picobarn = pico*barn

const double	nm = nanometer

const double	mm = millimeter

const double	mm2 = millimeter2

const double	mm3 = millimeter3

const double	cm = centimeter

const double	cm2 = centimeter2

const double	cm3 = centimeter3

const double	m = meter

const double	m2 = meter2

const double	m3 = meter3

const double	km = kilometer

const double	km2 = kilometer2

const double	km3 = kilometer3

const double	radian = 1.

const double	milliradian = milli*radian

const double	degree = (3.14159265358979323846/180.0)*radian

const double	steradian = 1.

const double	rad = radian

const double	mrad = milliradian

const double	sr = steradian

const double	deg = degree

const double	nanosecond = 1.

const double	second = 1.e+9 *nanosecond

const double	millisecond = milli*second

const double	microsecond = micro*second

const double	picosecond = pico*second

const double	hertz = 1./second

const double	kilohertz = kilo*hertz

const double	megahertz = mega*hertz

const double	ns = nanosecond

const double	s = second

const double	ms = millisecond

const double	eplus = 1.

const double	e_SI = 1.60217733e-19

const double	coulomb = eplus/e_SI

const double	microcoulomb = micro*coulomb

const double	femtocoulomb = femto*coulomb

const double	fC = femtocoulomb

const double	megaelectronvolt = 1.

const double	electronvolt = 1.e-6*megaelectronvolt

const double	kiloelectronvolt = kilo*electronvolt

const double	gigaelectronvolt = giga*electronvolt

const double	teraelectronvolt = tera*electronvolt

const double	petaelectronvolt = peta*electronvolt

const double	joule = electronvolt/e_SI

const double	MeV = megaelectronvolt

const double	eV = electronvolt

const double	keV = kiloelectronvolt

const double	GeV = gigaelectronvolt

const double	TeV = teraelectronvolt

const double	PeV = petaelectronvolt

const double	kilogram = joulesecondsecond/(meter*meter)

const double	gram = 1.e-3*kilogram

const double	milligram = milli*gram

const double	kg = kilogram

const double	g = gram

const double	mg = milligram

const double	watt = joule/second

const double	newton = joule/meter

const double	pascal = newton/m2

const double	bar = 100000*pascal

const double	atmosphere = 101325*pascal

const double	ampere = coulomb/second

const double	milliampere = milli*ampere

const double	microampere = micro*ampere

const double	nanoampere = nano*ampere

const double	megavolt = megaelectronvolt/eplus

const double	kilovolt = 1.e-3*megavolt

const double	volt = 1.e-6*megavolt

const double	ohm = volt/ampere

const double	farad = coulomb/volt

const double	millifarad = milli*farad

const double	microfarad = micro*farad

const double	nanofarad = nano*farad

const double	picofarad = pico*farad

const double	weber = volt*second

const double	tesla = volt*second/meter2

const double	gauss = 1.e-4*tesla

const double	kilogauss = 1.e-1*tesla

const double	henry = weber/ampere

const double	kelvin = 1.

const double	mole = 1.

const double	becquerel = 1./second

const double	curie = 3.7e+10 * becquerel

const double	gray = joule/kilogram

const double	candela = 1.

const double	lumen = candela*steradian

const double	lux = lumen/meter2

const double	perCent = 0.01

const double	perThousand = 0.001

const double	perMillion = 0.000001

Detailed Description

A coherent system of units 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 practical units (i.e. mostly the SI units). We can add our 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 unit definitions are defined in HEPUnits.hxx

The (non-unit) physical constants are defined in HEPConstants.hxx

This is taken from CLHEP and originated with GEANT4. It is included here so that we don't have to depend on CLHEP. All of the units are in the units:: namespace.

Variable Documentation

§ alpha_rcl2

const double units::alpha_rcl2

Initial value:

= fine_structure_const
    *classic_electr_radius
    *classic_electr_radius

Definition at line 109 of file HEPConstants.hxx.

§ twopi_mc2_rcl2

const double units::twopi_mc2_rcl2

Initial value:

= twopi*electron_mass_c2
    *classic_electr_radius
    *classic_electr_radius

Definition at line 113 of file HEPConstants.hxx.

Variables

Detailed Description

Variable Documentation

§ alpha_rcl2

§ twopi_mc2_rcl2