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#ifndef MANTID_PHYSICALCONSTANTS_H_
#define MANTID_PHYSICALCONSTANTS_H_
#include <cmath>
// NAN is not defined in Visual C++ < 2013
#if (defined(_MSC_VER) && (_MSC_VER <= 1800))
#define INFINITY (DBL_MAX + DBL_MAX)
#define NAN (INFINITY - INFINITY)
/** A namespace containing physical constants that are required by algorithms
and unit routines.
Copyright © 2007-2010 ISIS Rutherford Appleton Laboratory, NScD Oak
Ridge National Laboratory & European Spallation Source
This file is part of Mantid.
Mantid is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
Mantid 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
File change history is stored at: <https://github.com/mantidproject/mantid>.
Code Documentation is available at: <http://doxygen.mantidproject.org>
*/
namespace PhysicalConstants {
/** Avagodro constant in mol<SUP>-1</SUP>. Taken from
<http://physics.nist.gov/cuu/Constants> on 2010-12-28. */
static constexpr double N_A = 6.02214179e23;
/** Planck constant in J*s. Taken from <http://physics.nist.gov/cuu/Constants>
on 2007-10-31 and confirmed again on 2010-12-28. */
static constexpr double h = 6.62606896e-34;
/** Planck constant in J*s, divided by 2 PI. */
static constexpr double h_bar = h / (2 * M_PI);
/** Standard acceleration due to gravity. Precise value in ms<SUP>-2</SUP>. */
static constexpr double g = 9.80665;
/** Mass of the neutron in kg. Taken from
* <http://physics.nist.gov/cuu/Constants> on 30/10/2007. */
static constexpr double NeutronMass = 1.674927211e-27;
/** Mass of the neutron in AMU. Taken from
* <http://physics.nist.gov/cuu/Constants> on 02/01/2013. */
static constexpr double NeutronMassAMU = 1.008664916;
/** AMU in kg. Taken from <http://physics.nist.gov/cuu/Constants> on 10/09/2014.
*/
static constexpr double AtomicMassUnit = 1.660538921e-27;
/** 1 meV in Joules. Taken from <http://physics.nist.gov/cuu/Constants> on
* 28/03/2008. */
static constexpr double meV = 1.602176487e-22;
/** 1 meV in wavenumber (cm<SUP>-1</SUP>). Taken from
* <http://physics.nist.gov/cuu/Constants> on 02/04/2008. */
static constexpr double meVtoWavenumber = 8.06554465;
/** 1 meV in frequency (GHz). Division of energy by Plank's constant. Taken from
* <http://physics.nist.gov/cuu/Constants> on 03/11/2017. */
static constexpr double meVtoFrequency = 0.2417989262;
/** 1 meV in Kelvin. Taken from <http://physics.nist.gov/cuu/Constants> on
* 09/09/2011. */
static constexpr double meVtoKelvin = 11.604519;
/** Transformation coefficient to transform neutron energy into neutron
* wavevector: K-neutron[m^-10] = sqrt(E_neutron[meV]/E_transtormation[mEv]);*/
static constexpr double E_mev_toNeutronWavenumberSq =
1.0e20 * h_bar * h_bar / (2 * NeutronMass * meV); //[meV*Angstrom^2]
/** Muon lifetime. Taken from Particle Data Group on 15/1/2016
* <http://pdg.lbl.gov/2015/tables/rpp2015-sum-leptons.pdf>. */
static constexpr double MuonLifetime = 2.1969811e-6;
/** Standard atmospheric pressure in kPa.
* Taken from
* <http://physics.nist.gov/cgi-bin/cuu/Value?stdatm|search_for=adopted_in!> on
* 01/12/2010 **/
static constexpr double StandardAtmosphere = 101.325;
/** Boltzmann Constant in meV/K
* Taken from <http://physics.nist.gov/cuu/Constants> on 10/07/2012
*/
static constexpr double BoltzmannConstant = 8.6173324e-02;
/** Muon gyromagnetic ratio in MHz/G
* Taken from CalMuonDetectorPhases and DynamicKuboToyabe on 02/02/2016
*/
static constexpr double MuonGyromagneticRatio = 0.01355342;
} // namespace PhysicalConstants
} // namespace Mantid
#endif /*MANTID_PHYSICALCONSTANTS_H_*/