# Rayleigh Model¶

class rapoc.Rayleigh(atom, wavenumber_grid=None, model=None)[source]

The Rayleigh class estimates the Rayleigh scattering for the indicated atom using the equations from Chapter 10 of David R. Lide, ed., CRC Handbook of Chemistry and Physics, Internet Version 2005, hbcponline, CRC Press, Boca Raton, FL, 2005. These values won’t depend on pressure or temperature and therefore only a wavenumbers grid is needed to produce them. The wavenumbers grid can be given by the user or loaded from an already initialised Model class (as Rosseland or PLanck). The latter solution might be of help in using the Rayleigh scattering along with other opacities.

Parameters
• atom (str) – name of the considered atom

• wavenumber_grid (list or numpy.array or astropy.units.Quantity) – data wavenumber grid

• model (Model) – built model to use to load the wavenumbers grid.

Examples

First we prepare a data wavenumbers grid, then we can produce the Rayleigh data:

>>> rayleigh = Rayleigh('H', wavenumber_grid=[100000, 10000, 1000])


if we already have a molecular model loaded, as example built from a datafile, we can use it to initialise the Rayleigh class:

>>> input_data = Rosseland(input_data=exomol_file)
>>> rayleigh = Rayleigh(atom='Na', model=input_data)


Now the Rayleigh data are ready to be used as input data for any RAPOC Model class:

>>> pl = Planck(input_data=rayleigh)
>>> rs = Rosseland(input_data=rayleigh)

compute_opacities()[source]

It computes the opacities for Rayleigh scattering as described in David R. Lide, ed., CRC Handbook of Chemistry and Physics, Internet Version 2005, hbcponline, CRC Press, Boca Raton, FL, 2005. chapter 10 table 1:

$\alpha(\lambda) = \frac{128 \pi^5}{3 \lambda^4} \frac{a^2}{m}$

where $$a$$ is depending on the atom polarizabiility listed in table 2 chapter 10 of CRC handbook, and $$m$$ is the atom mass.

Returns

returns the estimated opacity sampled at the indicated wavenumbers.

Return type

astropy.units.Quantity

read_content()[source]

Reads the class content and returns the needed valued for the opacity models.

Returns

• str – molecule name

• astropy.units.Quantity – molecular mass

• astropy.units.Quantity – data pressure grid in si units

• astropy.units.Quantity – data temperature grid in si units

• astropy.units.Quantity – data wavenumber grid

• astropy.units.Quantity – data opacities grid in si units