SingleScattering¶

class nyx.atmosphere.single_scattering.SingleScattering[source]¶

Bases: AtmosphereModel

Single-scattering atmosphere, composed of named components.

Each ScatteringComponent supplies its own optical depth, phase function, single-scattering albedo, airmass and trainable parameters.

Build the atmosphere.

Parameters:

geo (Geometry)
components (dict of str to ScatteringComponent) – Components to compose, each built against geo.wvls.
airmass_formula (str) – Key into AIRMASS_FUNCTIONS.

Attributes Summary

components

Methods Summary

`evaluate`(sky)	Extinction and scattering kernel over the whole hemisphere.
`extinct`(altitudes, spectra, height_km)	Extinct point-source spectra, shape `(n_sources, n_wvl)`.
`from_hg`(geo[, aod_500, angstrom_exp, ...])	Rayleigh scattering plus Angstrom-law aerosol, no molecular absorption.
`from_hg_ozone`(geo[, aod_500, angstrom_exp, ...])	`from_hg()` plus an ozone absorption layer.
`scatter_sources`(sky, source_coords, ...)	Scatter discrete point sources onto the FOV grid.

Attributes Documentation

components = <dataclasses._MISSING_TYPE object>¶

Methods Documentation

evaluate(sky)[source]¶

Extinction and scattering kernel over the whole hemisphere.

Parameters:: sky (SkyGeometry)
Return type:: AtmosphereResult

extinct(altitudes, spectra, height_km)[source]¶: Extinct point-source spectra, shape (n_sources, n_wvl).

classmethod from_hg(geo, aod_500=0.1, angstrom_exp=1.5, hg_asymmetry=0.65, hg_ssa=0.9, airmass_formula='kasten_young_1989', pressure_hpa=None)[source]¶

Rayleigh scattering plus Angstrom-law aerosol, no molecular absorption.

Parameters:

geo (Geometry)
aod_500 (float) – Aerosol optical depth at 500 nm.
angstrom_exp (float) – Angstrom exponent.
hg_asymmetry (float) – Henyey-Greenstein asymmetry and aerosol single-scattering albedo.
hg_ssa (float) – Henyey-Greenstein asymmetry and aerosol single-scattering albedo.
airmass_formula (str) – Key into AIRMASS_FUNCTIONS.
pressure_hpa (float or None) – Station pressure for the Rayleigh column; None uses the barometric estimate from the observer height.

Return type:

SingleScattering

classmethod from_hg_ozone(geo, aod_500=0.1, angstrom_exp=1.5, hg_asymmetry=0.65, hg_ssa=0.9, airmass_formula='kasten_young_1989', pressure_hpa=None, ozone_height_km=25.0)[source]¶

from_hg() plus an ozone absorption layer.

Parameters:

geo (Geometry)
aod_500 (float)
angstrom_exp (float)
hg_asymmetry (float)
hg_ssa (float)
airmass_formula (str)
pressure_hpa (float or None) – Station pressure for the Rayleigh column; None uses the barometric estimate from the observer height.
ozone_height_km (float or None) – Height of the ozone layer, used for its own airmass; None puts it back on the shared airmass formula.

Return type:

SingleScattering

scatter_sources(sky, source_coords, source_spectra, bp)[source]¶

Scatter discrete point sources onto the FOV grid.

Parameters:

sky (SkyGeometry)
source_coords (jax.Array, shape (n_src, 2)) – AltAz in radians.
source_spectra (jax.Array, shape (n_src, n_wvl))
bp (jax.Array, shape (n_wvl,)) – Bandpass weights.

Return type:

jax.Array, shape (n_lon, n_lat)

__init__(geo, components, airmass_formula='kasten_young_1989')[source]¶

Build the atmosphere.

Parameters:

geo (Geometry)
components (dict of str to ScatteringComponent) – Components to compose, each built against geo.wvls.
airmass_formula (str) – Key into AIRMASS_FUNCTIONS.

static __new__(cls, *args, **kwargs)¶