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XMM-Newton Science Analysis System


ssclib (ssclib-3.29.3) [xmmsas_20070708_1801-7.1.0]

Meta Index / Home Page / A module which contains / Black Body routines

Per unit wavelength

The precision at long wavelengths L is limited by the calculation of exp(x)-1, where x = hk/TL. At low values of x, exp(x) is close to 1 and thus the difference between exp(x) and 1 is a number of low precision. Thus for x values less than 0.1, a series expansion of (exp(x)-1)/x is used instead. The minimum precision occurs at x = 0.1 and is approximately equal to precision(1d0)-1.

  subroutine getBBfluxPerMetre(angstromValues, kelvin, powerValues)
    real(double), intent(in)  :: angstromValues(:), kelvin
    real(double), intent(out) :: powerValues(size(angstromValues))
  end subroutine getBBfluxPerMetre

  function bbFluxPerMetre(angstroms, kelvin) result(power)
    real(double), intent(in) :: angstroms, kelvin
    real(double)             :: power
  end function bbFluxPerMetre