radis.phys.blackbody module

Notes

Planck functions: - planck: planck radiation with wavelength input - planck_wn: planck radiation with wavenumber input - sPlanck: a RADIS Spectrum blackbody object

Example

Generate Earth blackbody:

s = sPlanck(wavelength_min=3000, wavelength_max=50000,
            T=288, eps=1)
s.plot()

planck(lmbda, T, eps=1, unit='mW/sr/cm2/nm')[source]

Planck function for blackbody radiation.

\[\epsilon \frac{2h c^2}{{\lambda}^5} \frac{1}{\operatorname{exp}\left(\frac{h c}{\lambda k T}\right)-1}\]
Parameters
  • λ (np.array (nm)) – wavelength

  • T (float (K)) – equilibrium temperature

  • eps (grey-body emissivity) – default 1

  • unit (output unit) – default ‘mW/sr/cm2/nm’

Returns

np.array – equilibrium radiance

Return type

(mW.sr-1.cm-2/nm)

See also

sPlanck(), planck_wn()

planck_wn(wavenum, T, eps=1, unit='mW/sr/cm2/cm-1')[source]

Planck function for blackbody radiation, wavenumber version.

\[\epsilon 2h c^2 {\nu}^3 \frac{1}{\operatorname{exp}\left(\frac{h c \nu}{k T}\right)-1}\]
Parameters
  • wavenum (np.array (cm-1)) – wavenumber

  • T (float (K)) – equilibrium temperature

  • eps (grey-body emissivity) – default 1

  • unit (str) – output unit. Default ‘mW/sr/cm2/cm-1’

Returns

np.array – equilibrium radiance

Return type

default (mW/sr/cm2/cm-1)

See also

sPlanck(), planck()

sPlanck(wavenum_min=None, wavenum_max=None, wavelength_min=None, wavelength_max=None, T=None, eps=1, wstep=0.01, medium='air', **kwargs)[source]

Return a RADIS Spectrum object with blackbody radiation.

It’s easier to plug in a SerialSlabs() line-of-sight than the Planck radiance calculated by planck(). And you don’t need to worry about units as they are handled internally.

See Spectrum documentation for more information

Parameters
  • wavenum_min / wavenum_max (():math:cm^{-1})) – minimum / maximum wavenumber to be processed in \(cm^{-1}\).

  • wavelength_min / wavelength_max ((\(nm\))) – minimum / maximum wavelength to be processed in \(nm\).

  • T (float (K)) – blackbody temperature

  • eps (float [0-1]) – blackbody emissivity. Default 1

Other Parameters
  • wstep (float (cm-1 or nm)) – wavespace step for calculation

  • **kwargs (other keyword inputs) – all are forwarded to spectrum conditions. For instance you can add a ‘path_length=1’ after all the other arguments

Examples

Generate Earth blackbody:

s = sPlanck(wavelength_min=3000, wavelength_max=50000,
            T=288, eps=1)
s.plot()

Examples using sPlanck :

References

In wavelength:

\[\epsilon \frac{2h c^2}{{\lambda}^5} \frac{1}{\operatorname{exp}\left(\frac{h c}{\lambda k T}\right)-1}\]

In wavenumber:

\[\epsilon 2h c^2 {\nu}^3 \frac{1}{\operatorname{exp}\left(\frac{h c \nu}{k T}\right)-1}\]

See also

planck(), planck_wn()