Diffuse_Sky

class erwans3.Skymodel.Diffuse_Sky(nside: Optional[int] = None, model: Optional[str] = None, simu_type: str = 'SH', **kwargs)

Bases: SourceModel

Represents a diffuse sky source for generating simulated Skymaps.

This class inherits from SourceModel, which is an abstract base class defining the basic structure and functionality for different types of sky sources. Diffuse_Sky specializes in modeling diffuse or extended sky emissions such as the Global Sky Model (GSM) or the Ultralong-wavelength Sky Model with Absorption Effect (ULSA).

Parameters:

• nside (int, optional) – HEALPix NSIDE parameter for the Skymap. Default is None.

• model (str, optional) – Model type for the diffuse sky. Default is None.

• simu_type (str, optional) – Type of simulation (‘SH’ for spherical harmonic simulation, ‘pixmap’ for pixel-based simulation). Default is ‘SH’.

• **kwargs (dict, optional) – Additional keyword arguments for model parameters.

See also

SourceModel

Base class for source models.

Examples

>>> ds = Diffuse_Sky(nside=2**6, model='gsm')
>>> ds.pre_comp(freqs=20*u.MHz, times=obs_time)
>>> simu_map = ds.make_source_simu(freq=20*u.MHz, time=obs_time, observer=my_observer)

Explanation (by chat-GPT)

The Diffuse_Sky class is designed to represent diffuse sky emissions for simulation purposes. It can handle various models of diffuse sky emissions, such as the Global Sky Model (GSM) or other custom models. By specifying the desired NSIDE (HEALPix resolution parameter) and model type, users can generate simulated Skymaps representing the diffuse sky emissions at different frequencies and times. The pre_comp method pre-computes necessary values based on the provided parameters, optimizing the simulation process. The make_source_simu method generates a simulation Skymap based on the specified frequency, time, and observer position.

Note that the choice of simulation type (SH or pixmap) impacts the simulation method used and the resulting Skymap format. SH simulations are suitable for high-resolution and large-scale maps, while pixmap simulations are more efficient for lower-resolution maps.

For detailed usage and examples, refer to the provided Examples section.

For more information on the underlying framework and base classes, see the See Also section.

Methods Summary

make_source_simu(freq, time[, observer])	Generate a simulation Skymap for the diffuse sky.
pre_comp([freqs, times, res_max])	Pre-compute values for the diffuse sky.

Methods Documentation

make_source_simu(freq: Quantity, time: Time, observer: Optional[Union[BaseCoordinateFrame, SkyCoord]] = None)

Generate a simulation Skymap for the diffuse sky.

Parameters:

• freq (Quantity [Hz]) – Frequency for simulation.

• time (Time) – Time for simulation.

• observer (BaseCoordinateFrame or SkyCoord or None, optional) – Observer frame for simulation.

Returns:

A Skymap object representing the simulation of the diffuse sky.

Return type:

Skymap

pre_comp(freqs: Optional[Quantity] = None, times: Optional[Time] = None, res_max: Optional[Quantity] = None)

Pre-compute values for the diffuse sky.

Parameters:

• freqs (Quantity [Hz] or None, optional) – Frequencies for pre-computation.

• times (Time or None, optional) – Times for pre-computation.

• res_max (Quantity [rad] or None, optional) – Maximum resolution for pre-computation.