pytmosph3r.emission

Module Contents

surface_projection(local_latitudes, n_per_latitudes, local_longitudes, n_per_longitudes, n_total_longitudes, obs_latitude, obs_longitude, planet_radius, local_projection)

Compute surface projection of local_latitudes and local_longitudes on the plane of the sky (as seen from the observer). local_projection is the output of the function.

class Emission(planet_to_star_flux_ratio=None, phase_curve=None, n_phases=None, surface_resolution=None, store_raw_flux=None, **kwargs)

Bases: pytmosph3r.log.Logger

The emission module computes the flux emitted by a body by iterating over the latitudes and longitudes of the model. It relies on Exo_k for the computation of the 1D flux in each column. The flux is then scaled with respected to the surface of the atmosphere projected onto the plane of the sky. A phase curve mode can be activated, in which case, we iterate over n_phases longitudes for the observer and scale the flux using the projection of the surface onto that direction.

Parameters

• planet_to_star_flux_ratio (bool) – The output spectrum will be a ratio between the flux of the planet and that of the star (instead of the flux of the planet).

• phase_curve (bool) – Activates the computation of the phase curve.

• n_phases (int) – Number of phases for the pĥase curve. Defaults to 100.

• surface_resolution (int) – Number of grid points to calculate projected surface (the more points, the more accurate). Defaults to 500.

• store_raw_flux (bool) – Whether or not to store raw flux (over each (latitude, longitude)).

• kwargs (dict) – See documentation of Exo_k to see what other options are available.

Returns

If planet_to_star_flux_ratio is True, the planet to star flux ratio (\(F_P/F_S * (R_P/R_S)^2\)), else the planet flux (in \(W/m^2/cm^{-1}\)).

Return type

(Spectrum)

planet_to_star_flux_ratio

Returns the planet to star flux ratio instead of the planet flux.

phase_curve_mode

Activates the computation of the phase curve.

n_phases

Number of phases in the phase curve.

flux

Output spectrum (Exo_k object).

surface_resolution

Number of grid points to calculate projected surface.

store_raw_flux

Whether or not to store raw flux (over each (latitude, longitude)).

build(self, model)

No need for an altitude-based grid (as done in transmission), so we just copy the input grid.

compute_projection(self)

Compute the projection surface of the grid cells over the plane of the sky.

compute(self, model)

Iterate over vertical columns (lat/lon) of the model, in which we use the exo_k 1D two-stream emission function (emission_spectrum_2stream() for the Atm class). Then integrate the output flux in the direction of the observer. For that, we compute the solid angle associated to the position of the observer, projecting the visible surface of the atmosphere onto the plane of the sky. The flux is scaled with respect to that projected surface. If planet_to_star_flux_ratio is True, the flux is scaled to the flux of the star (a blackbody). If the phase curve mode is activated, this function also computes a phase_curve object with the spectrum associated to all n_phases phase/observer longitudes (see compute_phase_curve()).

Parameters

model (Model) – Model in which to read latitudes, longitudes, pressure, etc.

Returns

Spectrum (either planet flux or planet-to-star flux ratio, following if planet_to_star_flux_ratio is activated).

Return type

Spectrum (exo_k object)

compute_phase_curve(self)

Computation of a phase curve, along n_phases observer longitudes. This function is called by compute().

inputs(self)

outputs(self)