import numpy as np
from typing import Optional, Tuple
import autoarray as aa
from autogalaxy.profiles.light.abstract import LightProfile
from autogalaxy.profiles.light.decorators import (
check_operated_only,
)
[docs]class ElsonFreeFall(LightProfile):
def __init__(
self,
centre: Tuple[float, float] = (0.0, 0.0),
ell_comps: Tuple[float, float] = (0.0, 0.0),
intensity: float = 0.1,
effective_radius: float = 0.6,
eta: float = 1.5,
):
"""
The elliptical Elson, Fall and Freeman (EFF) light profile, which is commonly used to represent the clumps of
Lyman-alpha emitter galaxies (see https://arxiv.org/abs/1708.08854).
Parameters
----------
centre
The (y,x) arc-second coordinates of the profile centre.
ell_comps
The first and second ellipticity components of the elliptical coordinate system.
intensity
Overall intensity normalisation of the light profile (units are dimensionless and derived from the data
the light profile's image is compared too, which is expected to be electrons per second).
effective_radius
The circular radius containing half the light of this profile.
eta
Scales the intensity gradient of the profile.
"""
super().__init__(centre=centre, ell_comps=ell_comps, intensity=intensity)
self.effective_radius = effective_radius
self.eta = eta
[docs] def image_2d_via_radii_from(self, grid_radii: np.ndarray) -> np.ndarray:
"""
Returns the 2D image of the Sersic light profile from a grid of coordinates which are the radial distances of
each coordinate from the its `centre`.
Parameters
----------
grid_radii
The radial distances from the centre of the profile, for each coordinate on the grid.
"""
np.seterr(all="ignore")
return self._intensity * (1 + (grid_radii / self.effective_radius) ** 2) ** (
-self.eta
)
[docs] @aa.grid_dec.grid_2d_to_structure
@check_operated_only
@aa.grid_dec.transform
@aa.grid_dec.relocate_to_radial_minimum
def image_2d_from(
self, grid: aa.type.Grid2DLike, operated_only: Optional[bool] = None
) -> np.ndarray:
"""
Returns the Eff light profile's 2D image from a 2D grid of Cartesian (y,x) coordinates.
If the coordinates have not been transformed to the profile's geometry (e.g. translated to the
profile `centre`), this is performed automatically.
Parameters
----------
grid
The 2D (y, x) coordinates in the original reference frame of the grid.
Returns
-------
image
The image of the Eff evaluated at every (y,x) coordinate on the transformed grid.
"""
return self.image_2d_via_radii_from(self.eccentric_radii_grid_from(grid))
@property
def half_light_radius(self) -> float:
return self.effective_radius * np.sqrt(0.5 ** (1.0 / (1.0 - self.eta)) - 1.0)
[docs]class ElsonFreeFallSph(ElsonFreeFall):
def __init__(
self,
centre: Tuple[float, float] = (0.0, 0.0),
intensity: float = 0.1,
effective_radius: float = 0.6,
eta: float = 1.5,
):
"""
The spherical Elson, Fall and Freeman (EFF) light profile, which is commonly used to represent the clumps of
Lyman-alpha emitter galaxies (see https://arxiv.org/abs/1708.08854).
Parameters
----------
centre
The (y,x) arc-second coordinates of the profile centre.
intensity
Overall intensity normalisation of the light profile (units are dimensionless and derived from the data
the light profile's image is compared too, which is expected to be electrons per second).
effective_radius
The circular radius containing half the light of this profile.
eta
Scales the intensity gradient of the profile.
"""
super().__init__(
centre=centre,
ell_comps=(0.0, 0.0),
intensity=intensity,
effective_radius=effective_radius,
eta=eta,
)