constants.hpp

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/** \file constants.hpp
 * \author Jared R. Males (jaredmales@gmail.com)
 * \brief Constants for astronomy.
 * \ingroup astrofiles
 *
 */
 
#ifndef __mx_astro_constants_hpp__
#define __mx_astro_constants_hpp__
 
namespace mx
{
 
namespace astro
{
 
namespace constants
{
 
/** \defgroup dimensionless_constants Dimensionless Constants
 * \ingroup astroconstants
 * Constants without dimensions are provided with a template argument specifying the precision.
 * @{
 */
 
/// Tangent of 1.0 arcsec
/** Calculated with 100 digits of precision, recorded here with 50 digits.
 */
template <typename realT>
constexpr realT tan_arcsec()
{
    return static_cast<realT>( 4.8481368111333441675396429478852851658848753880815e-06 );
}
 
///@} Dimensionless Constants
 
/** \defgroup dimensioned_constants Constants with Dimensions
 * \ingroup astroconstants
 * Constants with dimensions are provided with a template argument specifying the units system to use, see \ref
 * astrounits.
 * @{
 */
 
/// Newton's Gravitational Constant
/** Source: 2014 CODATA recommended values \cite codata_2014, http://physics.nist.gov/cuu/Constants/index.html
 */
template <typename units>
constexpr typename units::realT G()
{
    return static_cast<typename units::realT>( 6.67408e-11 ) * ( units::length * units::length * units::length ) /
           ( units::mass * units::time * units::time );
}
 
/// The speed of light.
/** Source: 2014 CODATA recommended values \cite codata_2014, http://physics.nist.gov/cuu/Constants/index.html
 */
template <typename units>
constexpr typename units::realT c()
{
    return static_cast<typename units::realT>( 299792458 ) * ( units::length / units::time );
}
 
/// Boltzmann Constant
/** \f$ k = 1.38064852 \times 10^{-23} \: J \: K^{-1}\f$
 *
 * Source: 2014 CODATA recommended values \cite codata_2014, http://physics.nist.gov/cuu/Constants/index.html
 */
template <typename units>
constexpr typename units::realT k()
{
    return static_cast<typename units::realT>( 1.38064852e-23 ) * units::energy / units::temperature;
}
 
/// Stefan-Boltzmann Constant
/** \f$ \sigma =  5.670367 \times 10^{-8} \: W \: m^{-2} \: K^{-4} \f$
 *
 * Source: 2014 CODATA recommended values \cite codata_2014, http://physics.nist.gov/cuu/Constants/index.html
 */
template <typename units>
constexpr typename units::realT sigma()
{
    return static_cast<typename units::realT>( 5.670367e-8 ) * ( units::energy / units::time ) /
           ( units::length * units::length ) /
           ( units::temperature * units::temperature * units::temperature * units::temperature );
}
 
/// Planck Constant
/** Source: 2014 CODATA recommended values \cite codata_2014, http://physics.nist.gov/cuu/Constants/index.html
 */
template <typename units>
constexpr typename units::realT h()
{
    return static_cast<typename units::realT>( 6.626070040e-34 ) * units::energy * units::time;
}
 
/// Length of day
/** As defined by IAU
 */
template <typename units>
constexpr typename units::realT day()
{
    return static_cast<typename units::realT>( 86400.0 ) * units::time;
}
 
/// Length of year
/** As defined by IAU
 */
template <typename units>
constexpr typename units::realT year()
{
    return ( static_cast<typename units::realT>( 365.25 ) * static_cast<typename units::realT>( 86400.0 ) ) *
           units::time;
}
 
/// Astronomical Unit
/** As defined by IAU Resolution 2012 B2
 */
template <typename units>
constexpr typename units::realT au()
{
    return static_cast<typename units::realT>( 149597870700.0 ) * units::length;
}
 
/// The parsec
template <typename units>
constexpr typename units::realT parsec()
{
    return au<units>() / tan_arcsec<typename units::realT>();
}
 
/// Radius of the Sun
/** \f$ R_{sun} = 6.957\times 10^{8} \: m\f$
 *
 * Source: IAU Resolution 2015 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2015_English.pdf">https://www.iau.org/static/resolutions/IAU2015_English.pdf</a>
 */
template <typename units>
constexpr typename units::realT radSun()
{
    return static_cast<typename units::realT>( 6.957e8 ) * units::length;
}
 
/// Solar Irradiance at 1 au
/** \f$ S_{sun} = 1361 \: W \: m^{-2}\f$
 *
 * Source: IAU Resolution 2015 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2015_English.pdf">https://www.iau.org/static/resolutions/IAU2015_English.pdf</a>
 */
template <typename units>
constexpr typename units::realT solarIrrad()
{
    return static_cast<typename units::realT>( 1361 ) * units::energy / units::time / ( units::length * units::length );
}
 
/// Luminosity of the Sun
/** \f$ L_{sun} = 3.828\times 10^{26} \: W\f$
 *
 * Source: IAU Resolution 2015 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2015_English.pdf">https://www.iau.org/static/resolutions/IAU2015_English.pdf</a>
 */
template <typename units>
constexpr typename units::realT lumSun()
{
    return static_cast<typename units::realT>( 3.828e26 ) * units::energy / units::time;
}
 
/// Effective Temperature of the Sun
/** \f$ T_{sun} = 5772 \: K \f$
 *
 * Source: IAU Resolution 2015 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2015_English.pdf">https://www.iau.org/static/resolutions/IAU2015_English.pdf</a>
 */
template <typename units>
constexpr typename units::realT TeffSun()
{
    return static_cast<typename units::realT>( 5772.0 ) * units::temperature;
}
 
/// Solar Mass Parameter
/** \f$ GM_{sun} =  1.3271244 \times 10^20 \: m^3 \: s^{-2} \f$
 *
 * Source: IAU Resolution 2015 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2015_English.pdf">https://www.iau.org/static/resolutions/IAU2015_English.pdf</a>
 */
template <typename units>
constexpr typename units::realT GMSun()
{
    return static_cast<typename units::realT>( 1.3271244e20 ) * ( units::length * units::length * units::length ) /
           ( units::time * units::time );
}
 
/// Solar Mass
/** The mass of Sun is the \ref GMSun() "Solar mass parameter" divided by the \ref G() "graviational constant".
 *
 * \f$ M_{Sun} =  GM_{Sun}/G \f$
 *
 */
template <typename units>
constexpr typename units::realT massSun()
{
    return GMSun<units>() / G<units>();
}
 
/// Radius of Earth (nominal equatorial)
/** \f$ R_{e} =  6.3781\times 10^6 \: m \f$
 *
 * Source: IAU Resolution 2015 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2015_English.pdf">https://www.iau.org/static/resolutions/IAU2015_English.pdf</a>
 */
template <typename units>
constexpr typename units::realT radEarth()
{
    return static_cast<typename units::realT>( 6.3781e6 ) * units::length;
}
 
/// Earth Mass Parameter
/** \f$ GM_{e} =  3.986004 \times 10^14 \: m^3 \: s^{-2} \f$
 *
 * Source: IAU Resolution 2015 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2015_English.pdf">https://www.iau.org/static/resolutions/IAU2015_English.pdf</a>
 */
template <typename units>
constexpr typename units::realT GMEarth()
{
    return static_cast<typename units::realT>( 3.986004e14 ) * ( units::length * units::length * units::length ) /
           ( units::time * units::time );
}
 
/// Earth Mass
/** The mass of Earth is the \ref GMEarth() "mass parameter"  divided by the \ref G() "gravitational constant".
 *
 * \f$ M_{e} =  GM_{e}/G \f$
 *
 */
template <typename units>
constexpr typename units::realT massEarth()
{
    return GMEarth<units>() / G<units>();
}
 
/// Radius of Jupiter (nominal equatorial)
/** \f$ R_{J} =  7.1492\times 10^7 \: m \f$
 *
 * Source: IAU Resolution 2015 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2015_English.pdf">https://www.iau.org/static/resolutions/IAU2015_English.pdf</a>
 */
template <typename units>
constexpr typename units::realT radJupiter()
{
    return static_cast<typename units::realT>( 7.1492e7 ) * units::length;
}
 
/// Jupiter Mass Parameter
/** \f$ GM_{J} =  1.2668653 \times 10^17 \: m^3 \: s^{-2} \f$
 *
 * Source: IAU Resolution 2015 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2015_English.pdf">https://www.iau.org/static/resolutions/IAU2015_English.pdf</a>
 */
template <typename units>
constexpr typename units::realT GMJupiter()
{
    return static_cast<typename units::realT>( 1.2668653e17 ) * ( units::length * units::length * units::length ) /
           ( units::time * units::time );
}
 
/// Jupiter Mass
/** The mass of Jupiter is the \ref GMJupiter() "Jupiter mass parameter"  divided by the \ref G()  "gravitational
 * constant".
 *
 * \f$ M_{J} =  GM_{J}/G \f$
 *
 */
template <typename units>
constexpr typename units::realT massJupiter()
{
    return GMJupiter<units>() / G<units>();
}
 
/// Mass ratio of Mercury to the Sun.
/**
 * \f$ M_{Sun}/M_{Me} = 6.023657330 \times 10^{6} \f$
 *
 * Source: IAU Resolution 2009 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2009_English.pdf">https://www.iau.org/static/resolutions/IAU2009_English.pdf</a>.
 * see also <a href="http://maia.usno.navy.mil/NSFA/NSFA_cbe.html">http://maia.usno.navy.mil/NSFA/NSFA_cbe.html</a>
 *
 */
template <typename units>
constexpr typename units::realT mrMercury()
{
    return static_cast<typename units::realT>( 6.023657330e6 );
}
 
/// Mass of Mercury.
/**
 * The mass of Mercury is the \ref massSun() "mass of the Sun" divided by the \ref mrMercury() "mass ratio of Mercury to
 * the Sun".
 *
 */
template <typename units>
constexpr typename units::realT massMercury()
{
    return massSun<units>() / mrMercury<units>();
}
 
/// Radius of Mercury.
/**
 * \f$ = 2.4397 \times 10^{6}
 *
 * Source: Seidelmann et al. (2007) \cite seidelmann_2007
 *
 */
template <typename units>
constexpr typename units::realT radMercury()
{
    return static_cast<typename units::realT>( 2.4397e6 ) * units::length;
}
 
/// Mass ratio of Venus to the Sun.
/**
 * \f$ M_{Sun}/M_{Ve} = 4.08523719 \times 10^{5}\f$
 *
 * Source: IAU Resolution 2009 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2009_English.pdf">https://www.iau.org/static/resolutions/IAU2009_English.pdf</a>.
 * see also <a href="http://maia.usno.navy.mil/NSFA/NSFA_cbe.html">http://maia.usno.navy.mil/NSFA/NSFA_cbe.html</a>
 *
 */
template <typename units>
constexpr typename units::realT mrVenus()
{
    return static_cast<typename units::realT>( 4.08523719e5 );
}
 
/// Mass of Venus.
/**
 * The mass of Venus is the \ref massSun() "mass of the Sun" divided by the \ref mrVenus() "mass ratio of Venus to the
 * Sun".
 *
 */
template <typename units>
constexpr typename units::realT massVenus()
{
    return massSun<units>() / mrVenus<units>();
}
 
/// Radius of Venus.
/**
 * \f$ = 6.0518 \times 10^{6}
 *
 * Source: Seidelmann et al. (2007) \cite seidelmann_2007
 *
 */
template <typename units>
constexpr typename units::realT radVenus()
{
    return static_cast<typename units::realT>( 6.0518e6 ) * units::length;
}
 
/// Mass ratio of Mars to the Sun.
/**
 * \f$ M_{Sun}/M_{Ma} = 3.09870359 \times 10^{6}\f$
 *
 * Source: IAU Resolution 2009 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2009_English.pdf">https://www.iau.org/static/resolutions/IAU2009_English.pdf</a>.
 * see also <a href="http://maia.usno.navy.mil/NSFA/NSFA_cbe.html">http://maia.usno.navy.mil/NSFA/NSFA_cbe.html</a>
 *
 */
template <typename units>
constexpr typename units::realT mrMars()
{
    return static_cast<typename units::realT>( 3.09870359e6 );
}
 
/// Mass of Mars.
/**
 * The mass of Mars is the mass of the Sun divided by the mass ratio of Mars to the Sun.
 *
 */
template <typename units>
constexpr typename units::realT massMars()
{
    return massSun<units>() / mrMars<units>();
}
 
/// Radius of Mars.
/**
 * \f$ = 3.39619 \times 10^{6}
 *
 * Source: Seidelmann et al. (2007) \cite seidelmann_2007
 *
 */
template <typename units>
constexpr typename units::realT radMars()
{
    return static_cast<typename units::realT>( 3.39619e6 ) * units::length;
}
 
/// Mass ratio of Saturn to the Sun.
/**
 * \f$ M_{Sun}/M_{Sa} = 3.4979018 \times 10^{3}\f$
 *
 * Source: IAU Resolution 2009 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2009_English.pdf">https://www.iau.org/static/resolutions/IAU2009_English.pdf</a>.
 * see also <a href="http://maia.usno.navy.mil/NSFA/NSFA_cbe.html">http://maia.usno.navy.mil/NSFA/NSFA_cbe.html</a>
 *
 */
template <typename units>
constexpr typename units::realT mrSaturn()
{
    return static_cast<typename units::realT>( 3.4979018e3 );
}
 
/// Mass of Saturn.
/**
 * The mass of Saturn is the mass of the Sun divided by the mass ratio of Saturn to the Sun.
 *
 */
template <typename units>
constexpr typename units::realT massSaturn()
{
    return massSun<units>() / mrSaturn<units>();
}
 
/// Radius of Saturn.
/**
 * \f$ = 6.0268 \times 10^{7}
 *
 * Source: Seidelmann et al. (2007) \cite seidelmann_2007
 *
 */
template <typename units>
constexpr typename units::realT radSaturn()
{
    return static_cast<typename units::realT>( 6.0268e7 ) * units::length;
}
 
/// Mass ratio of Uranus to the Sun.
/**
 * \f$ M_{Sun}/M_{U} = 2.2902951 \times 10^{4}\f$
 *
 * Source: IAU Resolution 2009 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2009_English.pdf">https://www.iau.org/static/resolutions/IAU2009_English.pdf</a>.
 * see also <a href="http://maia.usno.navy.mil/NSFA/NSFA_cbe.html">http://maia.usno.navy.mil/NSFA/NSFA_cbe.html</a>
 *
 */
template <typename units>
constexpr typename units::realT mrUranus()
{
    return static_cast<typename units::realT>( 2.2902951e4 );
}
 
/// Mass of Uranus.
/**
 * The mass of Uranus is the mass of the Sun divided by the mass ratio of Uranus to the Sun.
 *
 */
template <typename units>
constexpr typename units::realT massUranus()
{
    return massSun<units>() / mrUranus<units>();
}
 
/// Radius of Uranus.
/**
 * \f$ = 2.5559 \times 10^{7}
 *
 * Source: Seidelmann et al. (2007) \cite seidelmann_2007
 *
 */
template <typename units>
constexpr typename units::realT radUranus()
{
    return static_cast<typename units::realT>( 2.5559e7 ) * units::length;
}
 
/// Mass ratio of Neptune to the Sun.
/**
 * \f$ M_{Sun}/M_{U} = 1.941226 \times 10^{4}\f$
 *
 * Source: IAU Resolution 2009 B2, <a
 * href="https://www.iau.org/static/resolutions/IAU2009_English.pdf">https://www.iau.org/static/resolutions/IAU2009_English.pdf</a>.
 * see also <a href="http://maia.usno.navy.mil/NSFA/NSFA_cbe.html">http://maia.usno.navy.mil/NSFA/NSFA_cbe.html</a>
 *
 */
template <typename units>
constexpr typename units::realT mrNeptune()
{
    return static_cast<typename units::realT>( 1.941226e4 );
}
 
/// Mass of Neptune.
/**
 * The mass of Neptune is the mass of the Sun divided by the mass ratio of Neptune to the Sun.
 *
 */
template <typename units>
constexpr typename units::realT massNeptune()
{
    return massSun<units>() / mrNeptune<units>();
}
 
/// Radius of Neptune.
/**
 * \f$ = 2.4764 \times 10^{7}
 *
 * Source: Seidelmann et al. (2007) \cite seidelmann_2007
 *
 */
template <typename units>
constexpr typename units::realT radNeptune()
{
    return static_cast<typename units::realT>( 2.4764e7 ) * units::length;
}
 
///@} Dimensioned constants
 
} // namespace constants
} // namespace astro
} // namespace mx
 
#endif //__mx_astro_constants_hpp__