diff --git a/README.md b/README.md index 7e5c5e0..746cc00 100644 --- a/README.md +++ b/README.md @@ -1,6 +1,6 @@ -Here you can find a set of models describing the atmospheric refraction and dispersion. +*Here you can find a set of models describing the atmospheric refraction and dispersion.* -Contents: +**Contents:** - atmosphericModel.py : Python model that can be used to calculate the atmospheric refraction and dispersion - refractionModel.py : Python script that compares the output of the different rerfraction models. Can be used as an example on how to use atmosphericModel.py @@ -12,7 +12,8 @@ Contents: -On the dispersion model: +**On the dispersion model:** + Dispersion model from Ciddor, 1996, calculates the index of refraction of air using the following parameters: - Temperature - Pressure @@ -22,13 +23,14 @@ Dispersion model from Ciddor, 1996, calculates the index of refraction of air us -On the atmospheric refraction / atmospheric dispersion models: +**On the atmospheric refraction / atmospheric dispersion models:** + Available models: - Full integration using the refractive integral (requires detailed information about the atmosphere, e.g. 1976USSA.txt) - Plane-parallel atmosphere refraction model - Cassini's homogeneous atmosphere refraction model -- Oriani's theorem ( A*tan(z) + B^*tanˆ^3(z) ) -- Oriani's theorem expanded ( A*tan(z) + B*tanˆ^3(z) + C*tan^5(z) ) +- Oriani's theorem ( Atan(z) + Btan^3(z) ) +- Oriani's theorem expanded ( Atan(z) + Btan^3(z) + Ctan^5(z) ) - Error function refraction model @@ -42,4 +44,43 @@ Input parameters for the spherical atmosphere models (all but the first): - Latitude [deg] - Height above sea level [m] - Wavelength(s) [um] -- Zenith angle [deg] \ No newline at end of file +- Zenith angle [deg] + + +**Analytical error propagation** + +Full analytical error propagation is available for the Ciddor dispersion model (Observatory.dn_tph( ) ), for the Cassini refraction model (refraction.cassiniError( ) ) and for the Cassini dispersion model (dispersion.cassiniError( ) ). +The results agree well with a Monte Carlo simulation, suggesting that if additional errors have not been considered, they are of neglible importance. + +Uncertainties that are considered: + +Ciddor dispersion model: + +| Param. | Description | Unit | +| ------ | ------ | ------ | +| dl | Wavelength | um | +| dT | Temperature | K | +| dP | Pressure | Pa | +| dRH | Relative Humidity | | +| dCO2 | CO2 density | ppm | + + +Cassini refraction model: + +| Param. | Description | Unit | +| ------ | ------ | ------ | +| dn | Refractive index | | +| dz | Zenith angle | deg | + +Cassini dispersion model: + + +| Param. | Description | Unit | +| ------ | ------ | ------ | +| dl1, dl2 | Wavelength(s) | um | +| dT | Temperature | K | +| dP | Pressure | Pa | +| dRH | Relative Humidity | | +| dCO2 | CO2 density | ppm | +| dz | Zenith angle | deg | + \ No newline at end of file