QC.h

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// # QC.h: physical constants with units
// # Copyright (C) 1994,1995,1996,1997,1998,1999
// # Associated Universities, Inc. Washington DC, USA.
// #
// # This library is free software; you can redistribute it and/or modify it
// # under the terms of the GNU Library General Public License as published by
// # the Free Software Foundation; either version 2 of the License, or (at your
// # option) any later version.
// #
// # This library is distributed in the hope that it will be useful, but WITHOUT
// # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
// # License for more details.
// #
// # You should have received a copy of the GNU Library General Public License
// # along with this library; if not, write to the Free Software Foundation,
// # Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
// #
// # Correspondence concerning AIPS++ should be addressed as follows:
// #        Internet email: casa-feedback@nrao.edu.
// #        Postal address: AIPS++ Project Office
// #                        National Radio Astronomy Observatory
// #                        520 Edgemont Road
// #                        Charlottesville, VA 22903-2475 USA
 
#ifndef CASA_QC_H
#define CASA_QC_H
 
// # Includes
#include <casacore/casa/aips.h>
#include <casacore/casa/BasicSL/Constants.h>
#include <casacore/casa/Quanta/Quantum.h>
 
namespace casacore {  // # NAMESPACE CASACORE - BEGIN
 
// # Forward Declarations
 
// # Typedefs
 
// <summary>
// Physical constants (i.e. dimensioned values)
// </summary>
 
// <use visibility=export>
 
// <reviewed reviewer="UNKNOWN" date="before2004/08/25" tests="tQuantum">
 
// <prerequisite>
//   <li> <linkto class=Quantum>Quantum</linkto>
// </prerequisite>
 
// <etymology>
// A QC is based on the Quantum and C (constants) class
// </etymology>
 
// <synopsis>
// QC:name will produce a Quantity (Quantum&lt;Double&gt;) value consisting of
// a value and a unit. See the <linkto class=Quantum>Quantum</linkto> class
//  for possibilities of manipulating quanta.
// tQuantum will give a list of the currently available constants
// </synopsis>
 
// <example>
// To obtain the velocity of light in pc/a, use:
// <srcblock>
// #include <casacore/casa/Quanta.h>
// Double vel_pcpy = (C::c).convert("pc/a").getValue();
// </srcblock>
// </example>
 
// ############################################################################
// # NOTE:  Delete the following listing of the public data members when
// #        public data members are handled properly by the documentation
// #        extractor.
// ############################################################################
 
// The following constants are defined as public data members of class QC.
//
// <note role=caution>
// The following public data member documentation is currently extracted by
// hand, and thus could be out of date if this documentation was not updated
// when the class was modified.
// </note>
 
// <srcblock>
//
//    // vel of light
//    Quantum<Double> c( );
//
//    // Gravitational constant
//    Quantum<Double> G( );
//
//    // Planck
//    Quantum<Double> h( );
//
//    // HI line
//    Quantum<Double> HI( );
//
//    // Gas constant
//    Quantum<Double> R( );
//
//    // Avogadro
//    Quantum<Double> NA( );
//
//    // electron charge
//    Quantum<Double> e( );
//
//    // proton mass
//    Quantum<Double> mp( );
//
//    // mp/me
//    Quantum<Double> mp_me( );
//
//    // permeability vacuum
//    Quantum<Double> mu0( );
//
//    // permittivity vacuum
//    Quantum<Double> epsilon0( );
//
//    // Boltzmann
//    Quantum<Double> k( );
//
//    // Faraday
//    Quantum<Double> F( );
//
//    // mass electron
//    Quantum<Double> me( );
//
//    // radius electron
//    Quantum<Double> re( );
//
//    // Bohr's radius
//    Quantum<Double> a0( );
//
//    // Solar radius
//    Quantum<Double> R0( );
//
//    // IAU Gaussian grav. const **2
//    Quantum<Double> k2( );
//
//    // quarter turn = 90 degrees = pi/2 radians
//    Quantum<Double> qTurn( );
//
//    // half turn = 180 degrees = pi radians
//    Quantum<Double> hTurn( );
//
//    // full turn = 360 degrees = 2pi radians
//    Quantum<Double> fTurn( );
//
// </srcblock>
 
// <motivation>
// Physical constants should be known with their proper dimensions
// </motivation>
//
// <todo asof="941110">
// </todo>
 
class QC {
  friend class QC_init;
 
 public:
  // # If you change any of the public data members, make the corresponding
  // # change above to the documentation of the public data members.
 
  // vel of light
  inline static const Quantum<Double> &c() {
    static Quantum<Double> result(C::c, "m/s");
    return result;
  }
 
  // Gravitational constant
  inline static const Quantum<Double> &G() {
    static Quantum<Double> result(6.67259e-11, "N.m2/kg2");
    return result;
  }
 
  // Planck
  inline static const Quantum<Double> &h() {
    static Quantum<Double> result(6.6260755e-34, "J.s");
    return result;
  }
 
  // HI line
  inline static const Quantum<Double> &HI() {
    static Quantum<Double> result(1420.405751786, "MHz");
    return result;
  }
 
  // Gas constant
  inline static Quantum<Double> &R() {
    static Quantum<Double> result(8.314510, "J/K/mol");
    return result;
  }
 
  // Avogadro
  inline static const Quantum<Double> &NA() {
    static Quantum<Double> result(6.0221367e+23, "mol-1");
    return result;
  }
 
  // electron charge
  inline static const Quantum<Double> &e() {
    static Quantum<Double> result(1.60217733e-19, "C");
    return result;
  }
 
  // proton mass
  inline static const Quantum<Double> &mp() {
    static Quantum<Double> result(1.6726231e-27, "kg");
    return result;
  }
 
  // mp/me
  inline static const Quantum<Double> &mp_me() {
    static Quantum<Double> result(1836.152701, "");
    return result;
  }
 
  // permeability vacuum
  inline static const Quantum<Double> &mu0() {
    static Quantum<Double> result(4.0e-7 * M_PI, "H/m");
    return result;
  }
 
  // permittivity vacuum
  inline static const Quantum<Double> &epsilon0() {
    static Quantum<Double> result(1.0 / (4.0e-7 * M_PI * C::c * C::c), "F/m");
    return result;
  }
 
  // Boltzmann
  inline static const Quantum<Double> &k() {
    static Quantum<Double> result(8.314510 / 6.0221367e+23, "J/K");
    return result;
  }
 
  // Faraday
  inline static const Quantum<Double> &F() {
    static Quantum<Double> result(6.0221367e+23 * 1.60217733e-19, "C/mol");
    return result;
  }
 
  // mass electron
  inline static const Quantum<Double> &me() {
    static Quantum<Double> result(1.6726231e-27 / 1836.152701, "kg");
    return result;
  }
 
  // radius electron
  inline static const Quantum<Double> &re() {
    static Quantum<Double> result(2.8179e-15, "m");
    return result;
  }
 
  // Bohr's radius
  inline static const Quantum<Double> &a0() {
    static Quantum<Double> result(5.2918e-11, "m");
    return result;
  }
 
  // Solar radius
  inline static const Quantum<Double> &R0() {
    static Quantum<Double> result(6.9599e+08, "m");
    return result;
  }
 
  // IAU Gaussian grav. const **2
  inline static const Quantum<Double> &k2() {
    const Double IAU_k = 0.01720209895;
    static Quantum<Double> result(IAU_k * IAU_k, "AU3/d2/S0");
    return result;
  }
 
  // quarter turn = 90 degrees = pi/2 radians
  inline static const Quantum<Double> &qTurn() {
    static Quantum<Double> result(90.0, "deg");
    return result;
  }
 
  // half turn = 180 degrees = pi radians
  inline static const Quantum<Double> &hTurn() {
    static Quantum<Double> result(180.0, "deg");
    return result;
  }
 
  // full turn = 360 degrees = 2pi radians
  inline static const Quantum<Double> &fTurn() {
    static Quantum<Double> result(360.0, "deg");
    return result;
  }
};
 
}  // namespace casacore
 
#endif