C-----------------------------------------------------------------------
C !F77-INC
C
C !DESCRIPTION:
C    Fundamental constants for Planck functions.
C
C !INPUT PARAMETERS:
C    None
C
C !OUTPUT PARAMETERS:
C    None
C
C !REVISION HISTORY:
C
C !TEAM-UNIQUE HEADER:
C    Developed by the MODIS Group, CIMSS/SSEC, UW-Madison.
C
C !END
C-----------------------------------------------------------------------

c  Fundamental constants required for the monochromatic
c  Planck function routines PLANCK_M, PLANC_M, BRIGHT_M, BRITE_M
c
c  Taken from the NIST Reference on Constants, Units, and Uncertainty
c
c  http://physics.nist.gov/cuu/Constants/
c
c  See also:
c
c  Mohr, P.J. and B.N. Taylor, "CODATA recommended values of the
c    fundamental physical constants: 1998", Reviews of Modern Physics,
c    Vol.72, No.2, 2000.

c ... Planck constant (Joule second)
      double precision h
      parameter (h = 6.62606876d-34)

c ... Speed of light in vacuum (meters per second)
      double precision c
      parameter (c = 2.99792458d+08)

c ... Boltzmann constant (Joules per Kelvin)      
      double precision k
      parameter (k = 1.3806503d-23)

c ... Derived constants      
      double precision c1, c2
      parameter (c1 = 2.0d+0 * h * c * c)
      parameter (c2 = (h * c) / k)