Difference between revisions of "Rayleigh scattering"
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To be noticed : | To be noticed : | ||
| − | + | TAURAY(NW) is calculated in calc_rayleigh.F90. | |
| − | + | It is in fact TAUVAR which calculated, and then averaged by the black body function for each channel to give TAURAY : | |
| − | + | <math> \text{TAURAY(NW)} = \frac{\int_{\lambda' \in \text{channel}} \text{TAUVAR} (\lambda') B_{\lambda} \, \mathrm{d}\lambda'}{\int B_{\lambda} \, \mathrm{d}\lambda'} </math> | |
| − | |||
| − | <math> \text{TAURAY(NW)} = \frac{\int_{\lambda'} \text{TAUVAR} (\lambda') B_{\lambda} \, \mathrm{d}\lambda'}{\int B_{\lambda} \, \mathrm{d}\lambda'} </math> | ||
<math> \displaystyle \tau(\lambda) </math> is called TAUVAR | <math> \displaystyle \tau(\lambda) </math> is called TAUVAR | ||
Revision as of 15:06, 28 September 2022
About Rayleigh scattering in LMDZ Generic
Formalism
References
Hansen (1974) : https://ui.adsabs.harvard.edu/link_gateway/1974SSRv...16..527H/ADS_PDF
Rayleigh routine in exo_k : http://perso.astrophy.u-bordeaux.fr/~jleconte/exo_k-doc/_modules/exo_k/rayleigh.html#Rayleigh.sigma_mol
Exo_k uses formalism from : Caldas (2019) : https://hal.archives-ouvertes.fr/hal-02005332/document
Equation
in optcv.F90 :
TRAY(K,NW) = TAURAY(NW) * DPR(K)
In exo_k we have :
TRAY \( \displaystyle = \sigma_{exok} dN \) with \( \displaystyle \sigma_{exok} \) the cross section and dN in molecules/m2
which gives : TRAY \( \displaystyle = \sigma_{exok} \frac{dm}{m_{molecule}} \) with dm in kg/m2
and then : TRAY \( \displaystyle = \frac{\sigma_{exok}}{g * m_{molecule}} dP\)
so
\( \displaystyle \text{TAURAY} = \frac{\sigma_{exok}}{g * m_{molecule}} \)
To be noticed :
TAURAY(NW) is calculated in calc_rayleigh.F90.
It is in fact TAUVAR which calculated, and then averaged by the black body function for each channel to give TAURAY \[ \text{TAURAY(NW)} = \frac{\int_{\lambda' \in \text{channel}} \text{TAUVAR} (\lambda') B_{\lambda} \, \mathrm{d}\lambda'}{\int B_{\lambda} \, \mathrm{d}\lambda'} \]
\( \displaystyle \tau(\lambda) \) is called TAUVAR
