Difference between revisions of "Rayleigh scattering"
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here | here | ||
| − | TRAY <math> \displaystyle = \sigma_{exok} | + | TRAY <math> \displaystyle = \sigma_{exok} dN </math> with dm in kg/m2 |
| − | TRAY <math> \displaystyle = \frac{\sigma_{exok}}{g | + | TRAY <math> \displaystyle = \sigma_{exok} \frac{dm}{m_{molecule}} </math> with dm in kg/m2 |
| + | |||
| + | TRAY <math> \displaystyle = \frac{\sigma_{exok}}{g m_{molecule}} dP</math> | ||
so | so | ||
<math> \displaystyle \tau_{RAY}(\lambda) = \frac{\sigma_{exok}}{g * m_{molecule}} </math> | <math> \displaystyle \tau_{RAY}(\lambda) = \frac{\sigma_{exok}}{g * m_{molecule}} </math> | ||
Revision as of 14:50, 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)
We write \( \displaystyle TRAY = \tau_{RAY} dP\)
TAURAY(NW) is calculated in calc_rayleigh.F90
TAURAY(NW) \[ \displaystyle \tau_{RAY} = \frac{\int \tau(\lambda) B_{\lambda} \, \mathrm{d}\lambda}{\int B_{\lambda} \, \mathrm{d}\lambda} \]
\( \displaystyle \tau(\lambda) \) is called TAUVAR
For a given \( \displaystyle \lambda \), we have \( \displaystyle TAURAY(\lambda) = \tau(\lambda) dP \)
here
TRAY \( \displaystyle = \sigma_{exok} dN \) with dm in kg/m2
TRAY \( \displaystyle = \sigma_{exok} \frac{dm}{m_{molecule}} \) with dm in kg/m2
TRAY \( \displaystyle = \frac{\sigma_{exok}}{g m_{molecule}} dP\)
so
\( \displaystyle \tau_{RAY}(\lambda) = \frac{\sigma_{exok}}{g * m_{molecule}} \)
