Physical Constants¶

Constant contents¶

Constant introduction
Namespace o2scl_const
Namespace o2scl_mks
Namespace o2scl_cgs
Namespace o2scl_cgsm

Constant introduction¶

The constants from GSL are reworked with the type const double and placed in namespaces called o2scl_mks, o2scl_cgs, and o2scl_mksa. The GSL MKSA constants are identical to the MKS constants and thus are not duplicated here. The numerical constants from gsl_num and some other additional constants are given in the namespace o2scl_const, Some of the numerical values have been updated with CODATA 2018 values.

The find_constants class contains a simple constant database which can be searched at compiled time and also provides the constant database to acol -constants (see The acol Command Line Utility).

These physical constants can also be used to create unit conversion factors, described in Unit Conversions.

Namespace o2scl_const¶

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namespace o2scl_const¶

Constants.

CODATA 2014 values were from [Mohr16] and previous versions contained constants from [Luzum11] and [Mohr12] .

CODATA 2018 values are from physics.nist.gov/constants. IAU 2015 values are the nominal values from arXiv:1510.07674 and arXiv:1605.09788 .

Squared electron charge

const double e2_gaussian = o2scl_const::hc_mev_fm * o2scl_const::fine_structure_f<double>()¶

Electron charge squared in Gaussian units (derived)

In Gaussian Units:

\[\begin{split}\begin{eqnarray*} &\vec{\nabla} \cdot \vec{E} = 4 \pi \rho \, , \quad \vec{E}=-\vec{\nabla} \Phi \, , \quad \nabla^2 \Phi = - 4 \pi \rho \, , &\\& F=\frac{q_1 q_2}{r^2} \, , \quad W=\frac{1}{2} \int \rho V d^3 x =\frac{1}{8 \pi} \int | \vec{E} |^2 d^3 x \, , \quad \alpha=\frac{e^2}{\hbar c}=\frac{1}{137}& \end{eqnarray*}\end{split}\]

const double e2_hlorentz = o2scl_const::fine_structure_f<double>() * 4.0 * pi ¶

Electron charge sqaured in Heaviside-Lorentz units where \(\hbar=c=1\) (derived)

In Heaviside-Lorentz units:

\[\begin{split}\begin{eqnarray*} &\vec{\nabla} \cdot \vec{E} = \rho \, , \quad \vec{E}=-\vec{\nabla} \Phi \, , \quad \nabla^2 \Phi = - \rho \, , &\\& F=\frac{q_1 q_2}{4 \pi r^2} \, , \quad W=\frac{1}{2} \int \rho V d^3 x =\frac{1}{2} \int | \vec{E} |^2 d^3 x \, , \quad \alpha=\frac{e^2}{4 \pi}=\frac{1}{137}& \end{eqnarray*}\end{split}\]

const double e2_mks = o2scl_mks::electron_charge¶

Electron charge squared in SI(MKS) units (derived)

In MKS units:

\[\begin{split}\begin{eqnarray*} &\vec{\nabla} \cdot \vec{E} = \rho \, , \quad \vec{E}=-\vec{\nabla} \Phi \, , \quad \nabla^2 \Phi = - \rho \, , &\\& F=\frac{1}{4 \pi \varepsilon_0}\frac{q_1 q_2}{r^2} \, , \quad W=\frac{1}{2} \int \rho V d^3 x =\frac{\varepsilon_0}{2} \int | \vec{E} |^2 d^3 x \, , \quad \alpha=\frac{e^2}{4 \pi \varepsilon_0 \hbar c}=\frac{1}{137}& \end{eqnarray*}\end{split}\]

Note the conversion formulas

\[ q_HL=\sqrt{4 \pi} q_G = \frac{1}{\sqrt{\varepsilon_0}} q_{SI} \]

as mentioned, e.g. in pg. 13 of D. Griffiths Intro to Elem. Particles.

const double ec_gauss_fm2 = o2scl_mks::electron_charge * 1.0e-34 / o2scl_mks::plancks_constant_hbar¶: 1 \(\mathrm{Gauss}\) times the electron charge in Gaussian units in \(\mathrm{fm}^{-2}\)

const double gauss2_fm4 = ec_gauss_fm2 * ec_gauss_fm2 / o2scl_const::fine_structure_f<double>()¶

Conversion factor from \( \mathrm{Gauss}^2 \) to \(\mathrm{fm}^{-4}\) in Gaussian units.

This is useful, e.g. in converting magnetic field squared to an energy density.

Particle masses from PDG 2020

const double mass_lambda_MeV = 1115.683¶: \( \Lambda \) hyperon mass in \( \mathrm{MeV} \) (used value labeled “OUR FIT”)

const double mass_sigma_minus_MeV = 1197.449¶: \( \Sigma^{-} \) hyperon mass in \( \mathrm{MeV} \) (used value labeled “OUR FIT”)

const double mass_sigma_zero_MeV = 1192.642¶: \( \Sigma^{0} \) hyperon mass in \( \mathrm{MeV} \) (used value labeled “OUR FIT”)

const double mass_sigma_plus_MeV = 1189.37¶: \( \Sigma^{+} \) hyperon mass in \( \mathrm{MeV} \) (used value labeled “OUR FIT”)

const double mass_cascade_zero_MeV = 1314.86¶: \( \Xi^{0} \) hyperon mass in \( \mathrm{MeV} \) (used value labeled “OUR FIT”)

const double mass_cascade_minus_MeV = 1321.71¶: \( \Xi^{-} \) hyperon mass in \( \mathrm{MeV} \) (used value labeled “OUR FIT”)

const double mass_up_MeV = 2.16¶: Up quark mass in \( \mathrm{MeV} \) (used value labeled “OUR EVALUATION”)

const double mass_down_MeV = 4.67¶: Down quark mass in \( \mathrm{MeV} \) (used value labeled “OUR EVALUATION”)

const double mass_strange_MeV = 93.0¶: Strange quark mass in \( \mathrm{MeV} \) (used value labeled “OUR EVALUATION”)

Functions

template<class fp_t> fp_t fine_structure_f()¶: Fine structure constant (CODATA 2018 value)

template<class fp_t> fp_t avogadro_f()¶: Avogadro’s number (CODATA 2018 value; exact)

template<class fp_t> fp_t sin2_theta_weak_f()¶: \( \sin^2 \theta_W \) (PDG 2020 value)

template<class fp_t> fp_t gfermi_gev2_f()¶: Fermi coupling constant in \( \mathrm{GeV}^{-2} \) (CODATA 2018 value)

template<class fp_t> fp_t planck_f(size_t system = o2scl_mks)¶: Planck constant.

template<class fp_t> fp_t hbar_f(size_t system = o2scl_mks)¶: Reduced Planck constant.

template<class fp_t> fp_t speed_of_light_f(size_t system = o2scl_mks)¶: Speed of light.

template<class fp_t> fp_t boltzmann_f(size_t system = o2scl_mks)¶: Boltzmann’s constant.

template<class fp_t> fp_t hbarc_f(size_t system = o2scl_mks)¶: Reduced Planck’s constant times speed of light \( \hbar c \).

template<class fp_t> fp_t gravitational_constant_f(size_t system = o2scl_mks)¶

Gravitational constant (CODATA 2018 value)

Of course the gravitational constant is not known precisely, but this function ensures there is no additional noise in the multiprecision generalization.

template<class fp_t> fp_t elem_charge_f()¶: Elementary charge.

template<class fp_t> fp_t hc_mev_fm_f()¶: Reduced Planck constant times speed of light in \( \mathrm{MeV}~\mathrm{fm} \).

Variables

const double yotta = 1e24¶

const double zetta = 1e21¶

const double exa = 1e18¶

const double peta = 1e15¶

const double tera = 1e12¶

const double giga = 1e9¶

const double mega = 1e6¶

const double kilo = 1e3¶

const double milli = 1e-3¶

const double micro = 1e-6¶

const double nano = 1e-9¶

const double pico = 1e-12¶

const double femto = 1e-15¶

const double atto = 1e-18¶

const double zepto = 1e-21¶

const double yocto = 1e-24¶

static const size_t o2scl_mks = 1¶: MKS units.

static const size_t o2scl_cgs = 2¶: CGS units.

const double pi = boost::math::constants::pi<double>()¶: \( \pi \)

const double pi2 = boost::math::constants::pi_sqr<double>()¶: \( \pi^2 \)

const double root_pi = boost::math::constants::root_pi<double>()¶: \( \sqrt{\pi} \)

const double zeta32 = 2.6123753486854883433¶: \( \zeta(3/2) \)

const double zeta2 = boost::math::constants::zeta_two<double>()¶: \( \zeta(2) \)

const double zeta52 = 1.3414872572509171798¶: \( \zeta(5/2) \)

const double zeta3 = boost::math::constants::zeta_three<double>()¶: \( \zeta(3) \)

const double zeta5 = 1.0369277551433699263¶: \( \zeta(5) \)

const double zeta7 = 1.0083492773819228268¶: \( \zeta(7) \)

const double euler = boost::math::constants::euler<double>()¶: The Euler-Mascheroni constant.

const double hc_mev_fm = hc_mev_fm_f<double>()¶: \( \hbar c \) in MeV fm (exact)

const double hc_mev_cm = hc_mev_fm * 1.0e-13¶: \( \hbar c \) in MeV cm (exact)

const double mass_proton_amu = 1.007276466621¶: Mass of proton in amu from CODATA 2018.

Namespace o2scl_mks¶

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namespace o2scl_mks¶

Constants in MKS units.

Where possible, constants here are defined in terms of the values in o2scl_cgs, in order to make it easier to update these values. See also the documentation at o2scl_cgs .

Fundamental constants

const double speed_of_light = o2scl_cgs::speed_of_light / 1.0e2¶: Speed of light in m / s.

const double gravitational_constant = o2scl_cgs::gravitational_constant / 1.0e3¶: Newtonian constant of gravitation in m^3 / kg s^2.

const double plancks_constant_h = o2scl_cgs::plancks_constant_h / 1.0e7¶: Planck constant in kg m^2 / s.

const double plancks_constant_hbar = o2scl_cgs::plancks_constant_hbar / 1.0e7¶: Planck constant divided by 2 pi in kg m^2 / s.

const double electron_volt = o2scl_cgs::electron_volt / 1.0e7¶: Electron volt in kg m^2 / s^2.

const double boltzmann = o2scl_cgs::boltzmann / 1.0e7¶: Boltzmann constant in kg m^2 / K s^2.

const double bohr_radius = o2scl_cgs::bohr_radius / 1.0e2¶: Bohr radius in m.

const double stefan_boltzmann_constant = o2scl_cgs::stefan_boltzmann_constant / 1.0e3¶: Stefan-Boltzmann constant in kg / K^4 s^3.

const double thomson_cross_section = o2scl_cgs::thomson_cross_section / 1.0e4¶: Thomson cross section in m^2.

const double gfermi = o2scl_cgs::gfermi * 1.0e14¶: Fermi coupling constant in s^4 / m^4 kg^2.

Solar system properties

const double solar_mass_parameter = o2scl_cgs::solar_mass_parameter ¶: Solar mass times gravitational constant in km^3 / s^2.

const double solar_mass = o2scl_cgs::solar_mass / 1.0e3¶: Mass of the sun in kg.

const double solar_radius = o2scl_cgs::solar_radius / 1.0e2¶: Radius of the sun in m.

const double solar_temperature = o2scl_cgs::solar_temperature ¶: Temperature of the sun’s photosphere in K.

const double solar_luminosity = o2scl_cgs::solar_luminosity ¶: Luminosity of sun in erg/s.

const double earth_mass_parameter = o2scl_cgs::earth_mass_parameter ¶: Earth mass times gravitational constant in m^3 / s^2.

const double earth_mass = o2scl_cgs::earth_mass / 1.0e3¶: Mass of the earth in kg.

const double earth_radius_equatorial = o2scl_cgs::earth_radius_equatorial / 1.0e2¶: Equatorial radius of earth in m.

const double earth_radius_polar = o2scl_cgs::earth_radius_polar / 1.0e2¶: Polar radius of earth in m.

const double jupiter_mass_parameter = o2scl_cgs::jupiter_mass_parameter ¶: Jupter mass times gravitational constant in m^3 / s^2.

const double jupiter_mass = o2scl_cgs::jupiter_mass / 1.0e3 / 1.0e2¶: Mass of jupiter in kg.

const double jupiter_radius_equatorial = o2scl_cgs::jupiter_radius_equatorial ¶: Equatorial radius of jupiter in m.

const double jupiter_radius_polar = o2scl_cgs::jupiter_radius_polar / 1.0e2¶: Polar radius of jupiter in m.

const double mercury_mass = o2scl_cgs::mercury_mass / 1.0e3¶: Mass of mercury in kg.

const double mercury_radius = o2scl_cgs::mercury_radius / 1.0e2¶: Radius of mercury in m.

const double venus_mass = o2scl_cgs::venus_mass / 1.0e3¶: Mass of venus in kg.

const double venus_radius = o2scl_cgs::venus_radius / 1.0e2¶: Radius of venus in m.

const double mars_mass = o2scl_cgs::mars_mass / 1.0e3¶: Mass of mars in kg.

const double mars_radius_equatorial = o2scl_cgs::mars_radius_equatorial / 1.0e2¶: Equatorial radius of mars in m.

const double mars_radius_polar = o2scl_cgs::mars_radius_polar / 1.0e2¶: Polar radius of mars in m.

const double saturn_mass = o2scl_cgs::saturn_mass / 1.0e3¶: Mass of saturn in kg.

const double saturn_radius_equatorial = o2scl_cgs::saturn_radius_equatorial / 1.0e2¶: Equatorial radius of saturn in m.

const double saturn_radius_polar = o2scl_cgs::saturn_radius_polar / 1.0e2¶: Polar radius of saturn in m.

const double uranus_mass = o2scl_cgs::uranus_mass / 1.0e3¶: Mass of uranus in kg.

const double uranus_radius_equatorial = o2scl_cgs::uranus_radius_equatorial / 1.0e2¶: Equatorial radius of uranus in m.

const double uranus_radius_polar = o2scl_cgs::uranus_radius_polar / 1.0e2¶: Polar radius of uranus in m.

const double neptune_mass = o2scl_cgs::neptune_mass / 1.0e3¶: Mass of neptune in kg.

const double neptune_radius_equatorial = o2scl_cgs::neptune_radius_equatorial / 1.0e2¶: Equatorial radius of neptune in m.

const double neptune_radius_polar = o2scl_cgs::neptune_radius_polar / 1.0e2¶: Polar radius of neptune in m.

const double pluto_mass = o2scl_cgs::pluto_mass / 1.0e3¶: Mass of pluto in kg.

const double pluto_radius = o2scl_cgs::pluto_radius / 1.0e2¶: Radius of pluto in m.

Astrophysical constants

const double astronomical_unit = o2scl_cgs::astronomical_unit / 1.0e2¶: Astronomical unit in m.

const double parsec = o2scl_cgs::parsec / 1.0e2¶: Parsec in \( \mathrm{m} \).

const double grav_accel = o2scl_cgs::grav_accel / 1.0e2¶: Acccleration due to gravity in m / s^2.

const double schwarzchild_radius = o2scl_cgs::schwarzchild_radius / 1.0e2¶: Schwarzchild radius in m.

const double sidereal_year = o2scl_cgs::sidereal_year ¶: Sidereal year in s (from https://pdg.lbl.gov/2021/reviews/contents_sports.html)

const double tropical_year = o2scl_cgs::tropical_year ¶: Tropical year in s (from https://pdg.lbl.gov/2021/reviews/contents_sports.html)

const double julian_year = o2scl_cgs::julian_year ¶: Julian year in s.

const double light_year = o2scl_cgs::light_year / 1.0e2¶: Light year in \( \mathrm{m} \).

Particle masses

const double mass_electron = o2scl_cgs::mass_electron / 1.0e3¶: Electron mass in kg.

const double mass_muon = o2scl_cgs::mass_muon / 1.0e3¶: Muon mass in kg.

const double mass_tau = o2scl_cgs::mass_tau / 1.0e3¶: Muon mass in kg.

const double mass_proton = o2scl_cgs::mass_proton / 1.0e3¶: Proton mass in kg.

const double mass_neutron = o2scl_cgs::mass_neutron / 1.0e3¶: Neutron mass in kg.

Nuclear masses

const double mass_deuteron = o2scl_cgs::mass_deuteron / 1.0e3¶: Deuteron mass in kg.

const double mass_triton = o2scl_cgs::mass_triton / 1.0e3¶: Triton mass in kg.

const double mass_helion = o2scl_cgs::mass_helion / 1.0e3¶: Helion mass in kg.

const double mass_alpha = o2scl_cgs::mass_alpha / 1.0e3¶: Alpha particle mass in kg.

const double unified_atomic_mass = o2scl_cgs::unified_atomic_mass / 1.0e3¶: Atomic mass constant in kg.

Chemical constants

const double rydberg = o2scl_cgs::rydberg / 1.0e7¶: Rydberg constant in kg m^2 / s^2.

const double molar_gas = o2scl_cgs::molar_gas / 1.0e7¶: kg m^2 / K mol s^2

const double standard_gas_volume = o2scl_cgs::standard_gas_volume / 1.0e6¶: m^3 / mol

Unit conversions

const double minute = o2scl_cgs::minute ¶: s

const double hour = o2scl_cgs::hour ¶: s

const double day = o2scl_cgs::day ¶: s

const double week = o2scl_cgs::week ¶: s

const double inch = o2scl_cgs::inch * 1.0e-2¶: m

const double foot = o2scl_cgs::foot * 1.0e-2¶: m

const double yard = o2scl_cgs::yard * 1.0e-2¶: m

const double mile = o2scl_cgs::mile * 1.0e-2¶: m

const double nautical_mile = o2scl_cgs::nautical_mile * 1.0e-2¶: m

const double fathom = o2scl_cgs::fathom * 1.0e-2¶: m

const double mil = o2scl_cgs::mil * 1.0e-2¶: m

const double point = o2scl_cgs::point * 1.0e-2¶: m

const double texpoint = o2scl_cgs::texpoint * 1.0e-2¶: m

const double micron = o2scl_cgs::micron * 1.0e-2¶: m

const double angstrom = o2scl_cgs::angstrom * 1.0e-2¶: m

const double hectare = o2scl_cgs::hectare * 1.0e-4¶: m^2

const double acre = o2scl_cgs::acre * 1.0e-4¶: m^2

const double barn = o2scl_cgs::barn * 1.0e-4¶: m^2

const double liter = o2scl_cgs::liter * 1.0e-6¶: m^3

const double us_gallon = o2scl_cgs::us_gallon * 1.0e-6¶: m^3

const double quart = o2scl_cgs::quart * 1.0e-6¶: m^3

const double pint = o2scl_cgs::pint * 1.0e-6¶: m^3

const double cup = o2scl_cgs::cup * 1.0e-6¶: m^3

const double fluid_ounce = o2scl_cgs::fluid_ounce * 1.0e-6¶: m^3

const double tablespoon = o2scl_cgs::tablespoon * 1.0e-6¶: m^3

const double teaspoon = o2scl_cgs::teaspoon * 1.0e-6¶: m^3

const double canadian_gallon = o2scl_cgs::canadian_gallon * 1.0e-6¶: m^3

const double uk_gallon = o2scl_cgs::uk_gallon * 1.0e-6¶: m^3

const double miles_per_hour = o2scl_cgs::miles_per_hour * 1.0e-2¶: m / s

const double kilometers_per_hour = o2scl_cgs::kilometers_per_hour * 1.0e-2¶: m / s

const double knot = o2scl_cgs::knot * 1.0e-2¶: m / s

const double pound_mass = o2scl_cgs::pound_mass * 1.0e-3¶: kg

const double ounce_mass = o2scl_cgs::ounce_mass * 1.0e-3¶: kg

const double ton = o2scl_cgs::ton * 1.0e-3¶: kg

const double metric_ton = o2scl_cgs::metric_ton * 1.0e-3¶: kg

const double uk_ton = o2scl_cgs::uk_ton * 1.0e-3¶: kg

const double troy_ounce = o2scl_cgs::troy_ounce * 1.0e-3¶: kg

const double carat = o2scl_cgs::carat * 1.0e-3¶: kg

const double gram_force = o2scl_cgs::gram_force * 1.0e-5¶: kg m / s^2

const double pound_force = o2scl_cgs::pound_force * 1.0e-5¶: kg m / s^2

const double kilopound_force = o2scl_cgs::kilopound_force * 1.0e-5¶: kg m / s^2

const double poundal = o2scl_cgs::poundal * 1.0e-5¶: kg m / s^2

const double calorie = o2scl_cgs::calorie * 1.0e-7¶: kg m^2 / s^2

const double btu = o2scl_cgs::btu * 1.0e-7¶: kg m^2 / s^2

const double therm = o2scl_cgs::therm * 1.0e-7¶: kg m^2 / s^2

const double horsepower = o2scl_cgs::horsepower * 1.0e-7¶: kg m^2 / s^3

const double bar = o2scl_cgs::bar * 1.0e-1¶: kg / m s^2

const double std_atmosphere = o2scl_cgs::std_atmosphere * 1.0e-1¶: kg / m s^2

const double torr = o2scl_cgs::torr * 1.0e-1¶: kg / m s^2

const double meter_of_mercury = o2scl_cgs::meter_of_mercury * 1.0e-1¶: kg / m s^2

const double inch_of_mercury = o2scl_cgs::inch_of_mercury * 1.0e-1¶: kg / m s^2

const double inch_of_water = o2scl_cgs::inch_of_water * 1.0e-1¶: kg / m s^2

const double psi = o2scl_cgs::psi * 1.0e-1¶: kg / m s^2

const double poise = o2scl_cgs::poise * 1.0e-1¶: kg m^-1 s^-1

const double stokes = o2scl_cgs::stokes * 1.0e-4¶: m^2 / s

const double gauss = 1.0e-4¶: kg / A s^2

const double stilb = o2scl_cgs::stilb * 1.0e4¶: cd / m^2

const double lumen = o2scl_cgs::lumen ¶: cd sr

const double lux = o2scl_cgs::lux * 1.0e4¶: cd sr / m^2

const double phot = o2scl_cgs::phot * 1.0e4¶: cd sr / m^2

const double footcandle = o2scl_cgs::footcandle * 1.0e4¶: cd sr / m^2

const double lambert = o2scl_cgs::lambert * 1.0e4¶: cd sr / m^2

const double footlambert = o2scl_cgs::footlambert * 1.0e4¶: cd sr / m^2

const double curie = o2scl_cgs::curie ¶: 1 / s

const double rad = o2scl_cgs::rad * 1.0e-4¶: m^2 / s^2

const double newton = o2scl_cgs::newton * 1.0e-5¶: kg m / s^2

const double dyne = o2scl_cgs::dyne * 1.0e-5¶: kg m / s^2

const double joule = o2scl_cgs::joule * 1.0e-7¶: kg m^2 / s^2

const double erg = o2scl_cgs::erg * 1.0e-7¶: kg m^2 / s^2

ELectromagnetic constants

const double electron_magnetic_moment = o2scl_cgsm::electron_magnetic_moment / 1.0e3¶: A m^2.

const double proton_magnetic_moment = o2scl_cgsm::proton_magnetic_moment / 1.0e3¶: A m^2.

const double roentgen = o2scl_cgs::roentgen * 1.0e3¶: A s / kg.

const double bohr_magneton = o2scl_cgsm::bohr_magneton / 1.0e3¶: Bohr magneton in A m^2.

const double nuclear_magneton = o2scl_cgsm::nuclear_magneton / 1.0e3¶: A m^2.

const double vacuum_permittivity = 8.8541878128e-12¶: A^2 s^4 / kg m^3 (derived)

const double vacuum_permeability = 1.25663706212e-6¶: Vacuum permeability in kg m / A^2 s^2.

const double faraday = o2scl_cgsm::faraday * 10.0¶: A s / mol.

const double electron_charge = o2scl_cgsm::electron_charge * 1.0e1¶: A s (derived)

Namespace o2scl_cgs¶

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namespace o2scl_cgs¶

Constants in CGS units.

CODATA 2014 values were from [Mohr16]. CODATA 2018 values are from physics.nist.gov/constants. IAU 2015 values are the nominal values from arXiv:1510.07674 and arXiv:1605.09788 .

Fundamental constants

const double speed_of_light = 2.99792458e10¶: Speed of light in \( \mathrm{cm}/\mathrm{s} \) (exact)

const double gravitational_constant = 6.67430e-8¶: Newtonian constant of gravitation in cm^3 / g s^2 (CODATA 2018 value)

const double plancks_constant_h = 6.62607015e-27¶: Planck constant in g cm^2 / s (CODATA 2018 value; exact)

const double plancks_constant_hbar = o2scl_cgs::plancks_constant_h / 2.0 / o2scl_const::pi ¶: Planck constant divided by 2 pi in g cm^2 / s (derived)

const double electron_volt = 1.602176634e-12¶: Electron volt in g cm^2 / s^2 (CODATA 2018; exact)

const double boltzmann = 1.380649e-16¶: Boltzmann constant in g cm^2 / K s^2 (CODATA 2018; exact)

const double bohr_radius = 5.29177210903e-9¶: Bohr radius in cm (CODATA 2018 value)

const double stefan_boltzmann_constant = o2scl_const::pi * o2scl_const::pi * o2scl_cgs::boltzmann * o2scl_cgs::boltzmann * o2scl_cgs::boltzmann * o2scl_cgs::boltzmann / 60.0 / o2scl_cgs::plancks_constant_hbar / o2scl_cgs::plancks_constant_hbar / o2scl_cgs::plancks_constant_hbar / o2scl_cgs::speed_of_light / o2scl_cgs::speed_of_light ¶: Stefan-Boltzmann constant in g / K^4 s^3 (CODATA 2018; derived; exact)

const double thomson_cross_section = 6.6524587321e-25¶: Thomson cross section in cm^2 (CODATA 2018 value)

const double gfermi = o2scl_const::gfermi_gev2_f<double>() * 1.0e-18 / o2scl_cgs::electron_volt / o2scl_cgs::electron_volt ¶: Fermi coupling constant in s^4 / cm^4 g^2 (derived from CODATA 2018 value)

Solar system properties

const double solar_mass_parameter = 1.3271244e26¶

Solar mass times gravitational constant in cm^3 / s^2 (IAU 2015 value, see https://arxiv.org/abs/1510.07674)

Note that this value differs slightly in Barycentric Coordinate Time and Barycentric Dynamical Time. This is the IAU’s nominal value.

const double solar_mass = solar_mass_parameter / gravitational_constant ¶: Mass of the sun in g (derived)

const double solar_radius = 6.957e10¶: Radius of the sun in cm (IAU 2015 nominal value)

const double solar_temperature = 5772.0¶: Temperature of the sun’s photosphere in K (IAU 2015 nominal value)

const double solar_luminosity = 3.828e40¶: Luminosity of sun in erg/s (IAU 2015 nominal value)

const double solar_irradiance = 1361.0¶: Solar total irradiance in W/m^2 (IAU 2015 nominal value)

const double earth_mass_parameter = 3.986004e20¶: Earth mass times gravitational constant in cm^3 / s^2 (IAU 2015 nominal values)

const double earth_mass = earth_mass_parameter / gravitational_constant ¶: Mass of the earth in g (derived)

const double earth_radius_equatorial = 6.3781e8¶: Equatorial radius of earth in cm (IAU 2015 value)

const double earth_radius_polar = 6.3568e8¶: Polar radius of earth in cm (IAU 2015 value)

const double jupiter_mass_parameter = 1.2668653e23¶: Jupter mass times gravitational constant in cm^3 / s^2 (IAU 2015 nominal values)

const double jupiter_mass = jupiter_mass_parameter / gravitational_constant ¶: Mass of jupiter in g (derived)

const double jupiter_radius_equatorial = 7.1492e9¶: Equatorial radius of jupiter in cm (IAU 2015 value)

const double jupiter_radius_polar = 6.6854e9¶: Polar radius of jupiter in cm (IAU 2015 value)

const double mercury_mass = 3.3011e26¶: Mass of mercury in g.

const double mercury_radius = 2.4397e8¶: Radius of mercury in cm.

const double venus_mass = 7.8675e27¶: Mass of venus in g.

const double venus_radius = 6.0518e8¶: Radius of venus in cm.

const double mars_mass = 6.4171e26¶: Mass of mars in g.

const double mars_radius_equatorial = 3.3962e8¶: Equatorial radius of mars in cm.

const double mars_radius_polar = 3.3762e8¶: Polar radius of mars in cm.

const double saturn_mass = 5.6834e29¶: Mass of saturn in g.

const double saturn_radius_equatorial = 6.0268e9¶: Equatorial radius of saturn in cm.

const double saturn_radius_polar = 5.4364e9¶: Polar radius of saturn in cm.

const double uranus_mass = 8.6810e28¶: Mass of uranus in g.

const double uranus_radius_equatorial = 2.5559e9¶: Equatorial radius of uranus in cm.

const double uranus_radius_polar = 2.4973e9¶: Polar radius of uranus in cm.

const double neptune_mass = 1.02413e29¶: Mass of neptune in g.

const double neptune_radius_equatorial = 2.4764e9¶: Equatorial radius of neptune in cm.

const double neptune_radius_polar = 2.4341e9¶: Polar radius of neptune in cm.

const double pluto_mass = 1.303e25¶: Mass of pluto in g.

const double pluto_radius = 1.1883e8¶: Radius of pluto in cm.

Astrophysical constants

const double astronomical_unit = 1.495978707e13¶: Astronomical unit in cm (IAU 2009 value; now exact)

const double parsec = o2scl_cgs::astronomical_unit * 648000.0 / o2scl_const::pi ¶: Parsec in \( \mathrm{cm} \) (derived; exact)

const double grav_accel = 9.80665e2¶: Acccleration due to gravity in cm / s^2 (CODATA 2018; now exact)

const double schwarzchild_radius = 2.0 * o2scl_cgs::solar_mass_parameter / o2scl_cgs::speed_of_light / o2scl_cgs::speed_of_light ¶: Schwarzchild radius in cm (derived)

const double sidereal_year = 31558149.8¶: Sidereal year in s (from https://pdg.lbl.gov/2021/reviews/contents_sports.html)

const double tropical_year = 31556925.1¶: Tropical year in s (from https://pdg.lbl.gov/2021/reviews/contents_sports.html)

const double julian_year = 365.25 * 8.64e4¶: Julian year in s (exact)

const double light_year = o2scl_cgs::julian_year * o2scl_cgs::speed_of_light ¶: Light year in \( \mathrm{cm} \) (derived; exact)

Particle masses

const double mass_electron = 9.1093837015e-28¶: Electron mass in g (CODATA 2018 value)

const double mass_muon = 1.883531627e-25¶: Muon mass in g (CODATA 2018 value)

const double mass_tau = 3.16754e-24¶: Muon mass in g (CODATA 2018 value)

const double mass_proton = 1.67262192369e-24¶: Proton mass in g (CODATA 2018 value)

const double mass_neutron = 1.67492749804e-24¶: Neutron mass in g (CODATA 2018 value)

Nuclear masses

const double mass_deuteron = 3.3435837724e-24¶: Deuteron mass in kg (CODATA 2018 value)

const double mass_triton = 5.0073567446e-24¶: Triton mass in kg (CODATA 2018 value)

const double mass_helion = 5.0064127796e-24¶: Helion mass in kg (CODATA 2018 value)

const double mass_alpha = 6.6446573357e-24¶: Alpha particle mass in kg (CODATA 2018 value)

const double unified_atomic_mass = 1.6605390666e-24¶: Atomic mass constant in g (CODATA 2018 value)

Chemical constants

const double rydberg = 2.1798723611035e-11¶: Rydberg constant in g cm^2 / s^2 (CODATA 2018 value)

const double molar_gas = o2scl_const::avogadro_f<double>() * o2scl_cgs::boltzmann ¶: Molar gas constant, “R”, in g cm^2 / K mol s^2 (CODATA 2018; exact; derived)

const double standard_gas_volume = 2.271095464e4¶: Molar volume of ideal gas at standard T and P in cm^3 / mol (CODATA 2018 value)

Unit conversions

const double minute = 6e1¶: s

const double hour = 3.6e3¶: s

const double day = 8.64e4¶: s

const double week = 6.048e5¶: s

const double inch = 2.54e0¶: cm

const double foot = 3.048e1¶: cm

const double yard = 9.144e1¶: cm

const double mile = 1.609344e5¶: cm

const double nautical_mile = 1.852e5¶: cm

const double fathom = 1.8288e2¶: cm

const double mil = 2.54e-3¶: cm

const double point = 3175.0 / 90000.0¶: cm

const double texpoint = 3.51459803515e-2¶: cm

const double micron = 1e-4¶: cm

const double angstrom = 1e-8¶: cm

const double hectare = 1e8¶: cm^2

const double acre = 4.04685642241e7¶: cm^2

const double barn = 1e-24¶: cm^2

const double liter = 1e3¶: cm^3

const double us_gallon = 3.78541178402e3¶: cm^3

const double quart = 9.46352946004e2¶: cm^3

const double pint = 4.73176473002e2¶: cm^3

const double cup = 2.36588236501e2¶: cm^3

const double fluid_ounce = 2.95735295626e1¶: cm^3

const double tablespoon = 1.47867647813e1¶: cm^3

const double teaspoon = 4.92892159375e0¶: cm^3

const double canadian_gallon = 4.54609e3¶: cm^3

const double uk_gallon = 4.546092e3¶: cm^3

const double miles_per_hour = 4.4704e1¶: cm / s

const double kilometers_per_hour = 250.0 / 9.0¶: cm / s

const double knot = 463.0 / 9.0¶: cm / s

const double pound_mass = 4.5359237e2¶: g

const double ounce_mass = 2.8349523125e1¶: g

const double ton = 9.0718474e5¶: g

const double metric_ton = 1e6¶: g

const double uk_ton = 1.0160469088e6¶: g

const double troy_ounce = 3.1103475e1¶: g

const double carat = 2e-1¶: g

const double gram_force = 9.80665e2¶: cm g / s^2

const double pound_force = 4.44822161526e5¶: cm g / s^2

const double kilopound_force = 4.44822161526e8¶: cm g / s^2

const double poundal = 1.38255e4¶: cm g / s^2

const double calorie = 4.1868e7¶: g cm^2 / s^2

const double btu = 1.05505585262e10¶: g cm^2 / s^2

const double therm = 1.05506e15¶: g cm^2 / s^2

const double horsepower = 7.457e9¶: g cm^2 / s^3

const double bar = 1e6¶: g / cm s^2

const double std_atmosphere = 1.01325e6¶: g / cm s^2

const double torr = 1.33322368421e3¶: g / cm s^2

const double meter_of_mercury = 1.33322368421e6¶: g / cm s^2

const double inch_of_mercury = 3.38638815789e4¶: g / cm s^2

const double inch_of_water = 2.490889e3¶: g / cm s^2

const double psi = 6.89475729317e4¶: g / cm s^2

const double poise = 1e0¶: g / cm s

const double stokes = 1e0¶: cm^2 / s

const double stilb = 1e0¶: cd / cm^2

const double lumen = 1e0¶: cd sr

const double lux = 1e-4¶: cd sr / cm^2

const double phot = 1e0¶: cd sr / cm^2

const double footcandle = 1.076e-3¶: cd sr / cm^2

const double lambert = 1e0¶: cd sr / cm^2

const double footlambert = 1.07639104e-3¶: cd sr / cm^2

const double curie = 3.7e10¶: 1 / s

const double rad = 1e2¶: cm^2 / s^2

const double newton = 1e5¶: cm g / s^2

const double dyne = 1e0¶: cm g / s^2

const double joule = 1e7¶: g cm^2 / s^2

const double erg = 1e0¶: g cm^2 / s^2

Electromagnetic constants

const double roentgen = 2.58e-7¶: A s / g.

Namespace o2scl_cgsm¶

Top

namespace o2scl_cgsm¶

Constants in CGSM units.

Where possible, constants here are defined in terms of the values in o2scl_cgs, in order to make it easier to update these values. See also the documentation at o2scl_cgs .

Fundamental constants

const double speed_of_light = o2scl_cgs::speed_of_light ¶: Speed of light in cm / s.

const double gravitational_constant = o2scl_cgs::gravitational_constant ¶: Newtonian constant of gravitation in cm^3 / g s^2.

const double plancks_constant_h = o2scl_cgs::plancks_constant_h ¶: Planck constant in g cm^2 / s.

const double plancks_constant_hbar = o2scl_cgs::plancks_constant_hbar ¶: Planck constant divided by 2 pi in g cm^2 / s.

const double electron_volt = o2scl_cgs::electron_volt ¶: Electron volt in g cm^2 / s^2.

const double boltzmann = o2scl_cgs::boltzmann ¶: Boltzmann constant in g cm^2 / K s^2.

const double bohr_radius = o2scl_cgs::bohr_radius ¶: Bohr radius in cm.

const double stefan_boltzmann_constant = o2scl_cgs::stefan_boltzmann_constant ¶: Stefan-Boltzmann constant in g / K^4 s^3.

const double thomson_cross_section = o2scl_cgs::thomson_cross_section ¶: Thomson cross section in cm^2.

const double gfermi = o2scl_cgs::gfermi ¶: Fermi coupling constant in s^4 / cm^4 g^2.

Solar system properties

const double solar_mass_parameter = o2scl_cgs::solar_mass_parameter ¶

Solar mass times gravitational constant in cm^3 / s^2 (IAU 2015 value)

Note that this value differs slightly in Barycentric Coordinate Time and Barycentric Dynamical Time. This is the IAU’s nominal value.

const double solar_mass = o2scl_cgs::solar_mass ¶: Mass of the sun in g (derived)

const double solar_radius = o2scl_cgs::solar_radius ¶: Radius of the sun in cm (IAU 2015 value)

const double solar_temperature = o2scl_cgs::solar_temperature ¶: Temperature of the sun’s photosphere in K (IAU 2015 value)

const double solar_luminosity = o2scl_cgs::solar_luminosity ¶: Luminosity of sun in erg/s (IAU 2015 value)

const double earth_mass_parameter = o2scl_cgs::earth_mass_parameter ¶: Earth mass times gravitational constant in cm^3 / s^2 (IAU 2015 value)

const double earth_mass = o2scl_cgs::earth_mass ¶: Mass of the earth in g (derived)

const double earth_radius_equatorial = o2scl_cgs::earth_radius_equatorial ¶: Equatorial radius of earth in cm (IAU 2015 value)

const double earth_radius_polar = o2scl_cgs::earth_radius_polar ¶: Polar radius of earth in cm (IAU 2015 value)

const double jupiter_mass_parameter = o2scl_cgs::jupiter_mass_parameter ¶: Jupter mass times gravitational constant in cm^3 / s^2 (IAU 2015 value)

const double jupiter_mass = o2scl_cgs::jupiter_mass ¶: Mass of jupiter in g (derived)

const double jupiter_radius_equatorial = o2scl_cgs::jupiter_radius_equatorial ¶: Equatorial radius of jupiter in cm (IAU 2015 value)

const double jupiter_radius_polar = o2scl_cgs::jupiter_radius_polar ¶: Polar radius of jupiter in cm (IAU 2015 value)

const double mercury_mass = o2scl_cgs::mercury_mass ¶: Mass of mercury in g.

const double mercury_radius = o2scl_cgs::mercury_radius ¶: Radius of mercury in cm.

const double venus_mass = o2scl_cgs::venus_mass ¶: Mass of venus in g.

const double venus_radius = o2scl_cgs::venus_radius ¶: Radius of venus in cm.

const double mars_mass = o2scl_cgs::mars_mass ¶: Mass of mars in g.

const double mars_radius_equatorial = o2scl_cgs::mars_radius_equatorial ¶: Equatorial radius of mars in cm.

const double mars_radius_polar = o2scl_cgs::mars_radius_polar ¶: Polar radius of mars in cm.

const double saturn_mass = o2scl_cgs::saturn_mass ¶: Mass of saturn in g.

const double saturn_radius_equatorial = o2scl_cgs::saturn_radius_equatorial ¶: Equatorial radius of saturn in cm.

const double saturn_radius_polar = o2scl_cgs::saturn_radius_polar ¶: Polar radius of saturn in cm.

const double uranus_mass = o2scl_cgs::uranus_mass ¶: Mass of uranus in g.

const double uranus_radius_equatorial = o2scl_cgs::uranus_radius_equatorial ¶: Equatorial radius of uranus in cm.

const double uranus_radius_polar = o2scl_cgs::uranus_radius_polar ¶: Polar radius of uranus in cm.

const double neptune_mass = o2scl_cgs::neptune_mass ¶: Mass of neptune in g.

const double neptune_radius_equatorial = o2scl_cgs::neptune_radius_equatorial ¶: Equatorial radius of neptune in cm.

const double neptune_radius_polar = o2scl_cgs::neptune_radius_polar ¶: Polar radius of neptune in cm.

const double pluto_mass = o2scl_cgs::pluto_mass ¶: Mass of pluto in g.

const double pluto_radius = o2scl_cgs::pluto_radius ¶: Radius of pluto in cm.

Astrophysical constants

const double astronomical_unit = o2scl_cgs::astronomical_unit ¶: Astronomical unit in cm (IAU 2009 value; now exact)

const double parsec = o2scl_cgs::parsec ¶: Parsec in \( \mathrm{cm} \) (derived; exact)

const double grav_accel = o2scl_cgs::grav_accel ¶: Acccleration due to gravity in cm / s^2 (CODATA 2018; now exact)

const double schwarzchild_radius = o2scl_cgs::schwarzchild_radius ¶: Schwarzchild radius in cm (derived)

const double sidereal_year = o2scl_cgs::sidereal_year ¶: Sidereal year in s (from https://pdg.lbl.gov/2021/reviews/contents_sports.html)

const double tropical_year = o2scl_cgs::tropical_year ¶: Tropical year in s (from https://pdg.lbl.gov/2021/reviews/contents_sports.html)

const double julian_year = o2scl_cgs::julian_year ¶: Julian year in s (exact)

const double light_year = o2scl_cgs::light_year ¶: Light year in \( \mathrm{cm} \) (derived; exact)

Particle masses

const double mass_electron = o2scl_cgs::mass_electron ¶: Electron mass in g.

const double mass_muon = o2scl_cgs::mass_muon ¶: Muon mass in g.

const double mass_tau = o2scl_cgs::mass_tau ¶: Muon mass in g.

const double mass_proton = o2scl_cgs::mass_proton ¶: Proton mass in g.

const double mass_neutron = o2scl_cgs::mass_neutron ¶: Neutron mass in g.

Nuclear masses

const double mass_deuteron = o2scl_cgs::mass_deuteron ¶: Deuteron mass in g.

const double mass_triton = o2scl_cgs::mass_triton ¶: Triton mass in g.

const double mass_helion = o2scl_cgs::mass_helion ¶: Helion mass in g.

const double mass_alpha = o2scl_cgs::mass_alpha ¶: Alpha particle mass in g.

const double unified_atomic_mass = o2scl_cgs::unified_atomic_mass ¶: Atomic mass constant in g.

Chemical constants

const double rydberg = o2scl_cgs::rydberg ¶: Rydberg constant in g cm^2 / s^2.

const double molar_gas = o2scl_cgs::molar_gas ¶: Molar gas constant, “R”, in g cm^2 / K mol s^2.

const double standard_gas_volume = o2scl_cgs::standard_gas_volume ¶: Molar volume of ideal gas at standard T and P in cm^3 / mol.

Unit conversions

const double minute = o2scl_cgs::minute ¶: s

const double hour = o2scl_cgs::hour ¶: s

const double day = o2scl_cgs::day ¶: s

const double week = o2scl_cgs::week ¶: s

const double inch = o2scl_cgs::inch ¶: cm

const double foot = o2scl_cgs::foot ¶: cm

const double yard = o2scl_cgs::yard ¶: cm

const double mile = o2scl_cgs::mile ¶: cm

const double nautical_mile = o2scl_cgs::nautical_mile ¶: cm

const double fathom = o2scl_cgs::fathom ¶: cm

const double mil = o2scl_cgs::mil ¶: cm

const double point = o2scl_cgs::point ¶: cm

const double texpoint = o2scl_cgs::texpoint ¶: cm

const double micron = o2scl_cgs::micron ¶: cm

const double angstrom = o2scl_cgs::angstrom ¶: cm

const double hectare = o2scl_cgs::hectare ¶: cm^2

const double acre = o2scl_cgs::acre ¶: cm^2

const double barn = o2scl_cgs::barn ¶: cm^2

const double liter = o2scl_cgs::liter ¶: cm^3

const double us_gallon = o2scl_cgs::us_gallon ¶: cm^3

const double quart = o2scl_cgs::quart ¶: cm^3

const double pint = o2scl_cgs::pint ¶: cm^3

const double cup = o2scl_cgs::cup ¶: cm^3

const double fluid_ounce = o2scl_cgs::fluid_ounce ¶: cm^3

const double tablespoon = o2scl_cgs::tablespoon ¶: cm^3

const double teaspoon = o2scl_cgs::teaspoon ¶: cm^3

const double canadian_gallon = o2scl_cgs::canadian_gallon ¶: cm^3

const double uk_gallon = o2scl_cgs::uk_gallon ¶: cm^3

const double miles_per_hour = o2scl_cgs::miles_per_hour ¶: cm / s

const double kilometers_per_hour = o2scl_cgs::kilometers_per_hour ¶: cm / s

const double knot = o2scl_cgs::knot ¶: cm / s

const double pound_mass = o2scl_cgs::pound_mass ¶: g

const double ounce_mass = o2scl_cgs::ounce_mass ¶: g

const double ton = o2scl_cgs::ton ¶: g

const double metric_ton = o2scl_cgs::metric_ton ¶: g

const double uk_ton = o2scl_cgs::uk_ton ¶: g

const double troy_ounce = o2scl_cgs::troy_ounce ¶: g

const double carat = o2scl_cgs::carat ¶: g

const double gram_force = o2scl_cgs::gram_force ¶: cm g / s^2

const double pound_force = o2scl_cgs::pound_force ¶: cm g / s^2

const double kilopound_force = o2scl_cgs::kilopound_force ¶: cm g / s^2

const double poundal = o2scl_cgs::poundal ¶: cm g / s^2

const double calorie = o2scl_cgs::calorie ¶: g cm^2 / s^2

const double btu = o2scl_cgs::btu ¶: g cm^2 / s^2

const double therm = o2scl_cgs::therm ¶: g cm^2 / s^2

const double horsepower = o2scl_cgs::horsepower ¶: g cm^2 / s^3

const double bar = o2scl_cgs::bar ¶: g / cm s^2

const double std_atmosphere = o2scl_cgs::std_atmosphere ¶: g / cm s^2

const double torr = o2scl_cgs::torr ¶: g / cm s^2

const double meter_of_mercury = o2scl_cgs::meter_of_mercury ¶: g / cm s^2

const double inch_of_mercury = o2scl_cgs::inch_of_mercury ¶: g / cm s^2

const double inch_of_water = o2scl_cgs::inch_of_water ¶: g / cm s^2

const double psi = o2scl_cgs::psi ¶: g / cm s^2

const double poise = o2scl_cgs::poise ¶: g / cm s

const double stokes = o2scl_cgs::stokes ¶: cm^2 / s

const double stilb = o2scl_cgs::stilb ¶: cd / cm^2

const double lumen = o2scl_cgs::lumen ¶: cd sr

const double lux = o2scl_cgs::lux ¶: cd sr / cm^2

const double phot = o2scl_cgs::phot ¶: cd sr / cm^2

const double footcandle = o2scl_cgs::footcandle ¶: cd sr / cm^2

const double lambert = o2scl_cgs::lambert ¶: cd sr / cm^2

const double footlambert = o2scl_cgs::footlambert ¶: cd sr / cm^2

const double curie = o2scl_cgs::curie ¶: 1 / s

const double rad = o2scl_cgs::rad ¶: cm^2 / s^2

const double newton = o2scl_cgs::newton ¶: cm g / s^2

const double dyne = o2scl_cgs::dyne ¶: cm g / s^2

const double joule = o2scl_cgs::joule ¶: g cm^2 / s^2

const double erg = o2scl_cgs::erg ¶: g cm^2 / s^2

Electromagnetic constants

const double electron_magnetic_moment = 9.2847647043e-21¶: Electron magnetic moment in abamp cm^2 (CODATA 2018 value)

const double proton_magnetic_moment = 1.41060679736e-23¶: Proton magnetic moment in abamp cm^2 (CODATA 2018 value)

const double roentgen = o2scl_cgs::roentgen / 10.0¶: Roentgen abamp s / g.

const double bohr_magneton = 9.2740100783e-21¶: Bohr magneton in abamp cm^2 (CODATA 2018 value)

const double nuclear_magneton = 5.0507837461e-24¶: Nuclear magneton in abamp cm^2 (CODATA 2018 value)

const double faraday = o2scl_const::avogadro_f<double>() * o2scl_cgs::electron_volt / 1.0e8¶: Faraday constant in abamp s / mol (CODATA 2018 value; derived; exact)

const double electron_charge = electron_volt * 1.0e-8¶: Electron charge in abamp s (derived)