coronagraphoto

Coronagraphic image simulation built on JAX.

Scene primitives (Star, Planet, Disk, System, Scene, backgrounds) live in skyscapes. coronagraphoto consumes a skyscapes.Scene and produces either deterministic count-rate maps (*_rate functions, differentiable, used for fitting and retrievals) or Poisson-realised detector readouts (*_readout functions, used for data generation).

Submodules

• coronagraphoto.datasets
• coronagraphoto.loaders
• coronagraphoto.simulation

Functions

load_scene_from_exovista(fits_file[, planet_indices, ...])	Load a full skyscapes.Scene from an ExoVista FITS file.
disk_rate(disk, optical_path, *, start_time_jd, ...)	Generate the disk count rate on the detector.
disk_readout(disk, optical_path, prng_key, *, ...)	Process a disk through the provided optical path.
planet_rate(planet, optical_path, *, start_time_jd, ...)	Generate the per-batch planet count rate on the detector.
planet_readout(planet, optical_path, prng_key, *, ...)	Process a per-batch Planet through the optical path.
star_rate(star, optical_path, *, start_time_jd, ...)	Generate the star count rate on the detector.
star_readout(star, optical_path, prng_key, *, ...)	Process a star through the provided optical path.
system_rate(scene, optical_path, *, start_time_jd, ...)	Sum of deterministic per-source count rates for a Scene.
system_readout(scene, optical_path, prng_key, *, ...)	Simulate a full Scene through the optical path.
zodi_rate(zodi, optical_path, *, start_time_jd, ...)	Generate the zodi count rate on the detector.
zodi_readout(zodi, optical_path, prng_key, *, ...)	Process a zodi source through the provided optical path.

Package Contents

coronagraphoto.load_scene_from_exovista(fits_file, planet_indices=None, only_earths=False, zodi_surface_brightness_mag=22.0)

Load a full skyscapes.Scene from an ExoVista FITS file.

Delegates system loading to skyscapes.from_exovista() and adds a default AYOZodi background using the host star’s wavelength grid.

The earlier required_planets parameter was removed: variadic planet tuples make the “pad to fixed shape” semantics unnecessary, and the underlying skyscapes.from_exovista no longer accepts it.

Args:

fits_file: Path to the ExoVista FITS file. planet_indices: Planet indices to load (0-based). None = all. only_earths: If True and planet_indices is None, auto-filter

Earths.

zodi_surface_brightness_mag: V-band surface brightness for the

default zodi background. Default 22.0 (AYO standard).

Returns:

skyscapes.Scene with the loaded system and a default zodi background.

Parameters:

• fits_file (str)

• planet_indices (collections.abc.Sequence[int] | None)

• only_earths (bool)

• zodi_surface_brightness_mag (float)

Return type:

skyscapes.Scene

coronagraphoto.disk_rate(disk, optical_path, *, start_time_jd, wavelength_nm, bin_width_nm, telescope_pa_deg, star, incl_deg, pa_deg)

Generate the disk count rate on the detector.

Disks return CONTRAST (dimensionless flux ratio relative to the host star); we multiply by star.spec_flux_density here to convert to photon flux density per pixel before resampling and PSF convolution.

incl_deg / pa_deg are the disk’s intrinsic orientation in the sky frame; telescope_pa_deg is the telescope’s roll. The disk is rendered at its intrinsic geometry, then resample_flux rotates the rendered image by -telescope_pa_deg into the detector frame.

Raises:

ValueError: if optical_path.coronagraph.psf_datacube is

None.

coronagraphoto.disk_readout(disk, optical_path, prng_key, *, start_time_jd, exposure_time_s, wavelength_nm, bin_width_nm, telescope_pa_deg, star, incl_deg, pa_deg)

Process a disk through the provided optical path.

incl_deg / pa_deg are the disk’s intrinsic sky-frame orientation; system_readout pulls them from scene.system.midplane_inc_deg / midplane_pa_deg so every disk component in the System renders at the same midplane.

coronagraphoto.planet_rate(planet, optical_path, *, start_time_jd, wavelength_nm, bin_width_nm, telescope_pa_deg, star, trig_solver)

Generate the per-batch planet count rate on the detector.

Operates on a single skyscapes.scene.Planet (which internally batches K planets sharing the same atmosphere class). The Python loop over a heterogeneous System.planets tuple lives in system_readout(); this function stays inside the per-Planet-type JIT cache boundary (see brain/Planet Loop Architecture.md).

coronagraphoto.planet_readout(planet, optical_path, prng_key, *, start_time_jd, exposure_time_s, wavelength_nm, bin_width_nm, telescope_pa_deg, star, trig_solver)

Process a per-batch Planet through the optical path.

coronagraphoto.star_rate(star, optical_path, *, start_time_jd, wavelength_nm, bin_width_nm)

Generate the star count rate on the detector.

coronagraphoto.star_readout(star, optical_path, prng_key, *, start_time_jd, exposure_time_s, wavelength_nm, bin_width_nm)

Process a star through the provided optical path.

coronagraphoto.system_rate(scene, optical_path, *, start_time_jd, wavelength_nm, bin_width_nm, telescope_pa_deg, ecliptic_lat_deg, solar_lon_deg)

Sum of deterministic per-source count rates for a Scene.

The differentiable companion to system_readout(). Returns the total rate map (electrons/s/pixel, no Poisson noise, no QE multiply) summing star, every planet, the optional disk, and the optional zodi. Use this for likelihood evaluation, retrievals, or any inference loop that needs gradients through the full forward model.

coronagraphoto.system_readout(scene, optical_path, prng_key, *, start_time_jd, exposure_time_s, wavelength_nm, bin_width_nm, telescope_pa_deg, ecliptic_lat_deg, solar_lon_deg)

Simulate a full Scene through the optical path.

Sums per-source detector readouts. Each source consumes its own independent PRNG subkey (see jax.random best practices).

The Python loop over scene.system.planets is intentionally unjitted – it orchestrates JIT-cached per-Planet-type kernels (see brain/Planet Loop Architecture.md). The expensive math is inside each planet_readout call, not the loop.

coronagraphoto.zodi_rate(zodi, optical_path, *, start_time_jd, wavelength_nm, bin_width_nm, ecliptic_lat_deg, solar_lon_deg)

Generate the zodi count rate on the detector.

Treats zodi as a spatially uniform surface-brightness source. The coronagraph’s sky transmission map sets the per-pixel attenuation; no PSF convolution is needed (a flat field convolved with any normalised PSF returns itself).

Parameters:

zodi (skyscapes.background.Zodi)

coronagraphoto.zodi_readout(zodi, optical_path, prng_key, *, start_time_jd, exposure_time_s, wavelength_nm, bin_width_nm, ecliptic_lat_deg, solar_lon_deg)

Process a zodi source through the provided optical path.

Parameters:

zodi (skyscapes.background.Zodi)