autogalaxy.profiles.mass.SersicCore

class SersicCore

Bases: Sersic

The elliptical cored-Sersic light profile.

Parameters:

• centre (Tuple[float, float]) – The (y,x) arc-second coordinates of the profile centre.

• ell_comps (Tuple[float, float]) – The first and second ellipticity components of the elliptical coordinate system.

• intensity (float) – 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 (float) – The circular radius containing half the light of this profile.

• sersic_index (float) – Controls the concentration of the profile (lower -> less concentrated, higher -> more concentrated).

• radius_break (float) – The break radius separating the inner power-law (with logarithmic slope gamma) and outer Sersic function.

• intensity – The intensity at the break radius.

• gamma (float) – The logarithmic power-law slope of the inner core profiles

• alpha (float) – Controls the sharpness of the transition between the inner core / outer Sersic profiles.

Methods

angle	The position angle in degrees of the major-axis of the ellipse defined by profile, defined counter clockwise from the positive x-axis (0.0 > angle > 180.0).
angle_radians	The position angle in radians of the major-axis of the ellipse defined by profile, defined counter clockwise from the positive x-axis (0.0 > angle > 2pi).
angle_to_profile_grid_from	The angle between each angle theta on the grid and the profile, in radians.
axis_ratio	The ratio of the minor-axis to major-axis (b/a) of the ellipse defined by profile (0.0 > q > 1.0).
convergence_2d_from	Calculate the projected convergence at a given set of arc-second gridded coordinates.
convergence_2d_via_cse_from	Calculate the projected 2D convergence from a grid of (y,x) arc second coordinates, by computing and summing the convergence of each individual cse used to decompose the mass profile.
convergence_cse_1d_from	One dimensional function which is solved to decompose a convergence profile in cored steep ellipsoids, given by equation (14) of Oguri 2021 (https://arxiv.org/abs/2106.11464).
convergence_func	Returns the convergence of the mass profile as a function of the radial coordinate.
decompose_convergence_via_cse	Decompose the convergence of the Sersic profile into cored steep elliptical (cse) profiles.
deflections_2d_via_cse_from	Calculate the projected 2D deflection angles from a grid of (y,x) arc second coordinates, by computing and summing the convergence of each individual cse used to decompose the mass profile.
deflections_2d_via_mge_from
deflections_2d_via_potential_2d_from	Returns the 2D deflection angles of the mass profile by numerically differentiating the lensing potential on the input grid.
deflections_via_cse_from	Returns the deflection angles of a 1d cored steep ellisoid (CSE) profile, given by equation (19) and (20) of Oguri 2021 (https://arxiv.org/abs/2106.11464).
deflections_yx_2d_from	Returns the 2D deflection angles of the mass profile from a 2D grid of Cartesian (y,x) coordinates.
density_between_circular_annuli	Calculate the mass between two circular annuli and compute the density by dividing by the annuli surface area.
eccentric_radii_grid_from	Convert a grid of (y,x) coordinates to an eccentric radius: :math: axis_ratio^0.5 (x^2 + (y^2/q))^0.5
elliptical_radii_grid_from	Convert a grid of (y,x) coordinates to their elliptical radii values: :math: (x^2 + (y^2/q))^0.5
extract_attribute	Returns an attribute of a class and its children profiles in the galaxy as a ValueIrregular or Grid2DIrregular object.
has	Returns True if any attribute of this profile is an instance of the input class cls, else False.
image_2d_via_radii_from	Calculate the intensity of the cored-Sersic light profile on a grid of radial coordinates.
intensity_prime	Overall intensity normalisation in the rescaled Core-Sersic light profiles (electrons per second)
mass_angular_within_circle_from	Integrate the mass profiles's convergence profile to compute the total mass within a circle of specified radius.
mass_integral	Integrand used by mass_angular_within_circle_from to compute the total projected mass within a circle.
potential_2d_from	Returns the 2D lensing potential of the mass profile from a 2D grid of Cartesian (y,x) coordinates.
potential_func	Returns the integrand of the lensing potential at a single point, used in numerical integration schemes for computing the potential from the mass profile's convergence.
radial_deflection_from
radial_grid_from	Convert a grid of (y, x) coordinates, to their radial distances from the profile centre (e.g. :math: r = sqrt(x**2 + y**2)).
rotated_grid_from_reference_frame_from	Rotate a grid of (y,x) coordinates which have been transformed to the elliptical reference frame of a profile back to the original unrotated coordinate grid reference frame.
transformed_from_reference_frame_grid_from	Transform a grid of (y,x) coordinates from the reference frame of the profile to the original observer reference frame.
transformed_to_reference_frame_grid_from	Transform a grid of (y,x) coordinates to the reference frame of the profile.
vmapped_deflections_from

Attributes

average_convergence_of_1_radius	The radius a critical curve forms for this mass profile, e.g. where the mean convergence is equal to 1.0.
elliptical_effective_radius	The effective_radius of a Sersic light profile is defined as the circular effective radius.
ellipticity_rescale	A rescaling factor applied to account for the ellipticity of the mass profile when computing the Einstein radius from the average convergence equals unity criterion.
sersic_constant	A parameter derived from Sersic index which ensures that effective radius contains 50% of the profile's total integrated light.

deflections_yx_2d_from(grid, xp=<module 'numpy' from '/home/docs/checkouts/readthedocs.org/user_builds/pyautolens/envs/latest/lib/python3.12/site-packages/numpy/__init__.py'>, **kwargs)

Returns the 2D deflection angles of the mass profile from a 2D grid of Cartesian (y,x) coordinates.

The deflection angle α(θ) at image-plane position θ describes how a light ray is bent by the gravitational field of the lens. The source-plane position β is then:

β = θ − α(θ)

Deflection angles are the single most important output of a mass profile — every other lensing quantity (convergence, shear, magnification, critical curves, caustics) can be derived from them.

Parameters:

grid (Union[ndarray, Grid2D, Grid2DIrregular]) – The 2D (y, x) coordinates where the deflection angles are evaluated.

Returns:

The (y, x) deflection angles at every coordinate on the input grid.

Return type:

aa.VectorYX2D

deflections_2d_via_mge_from(grid, xp=<module 'numpy' from '/home/docs/checkouts/readthedocs.org/user_builds/pyautolens/envs/latest/lib/python3.12/site-packages/numpy/__init__.py'>, **kwargs)

image_2d_via_radii_from(grid_radii, xp=<module 'numpy' from '/home/docs/checkouts/readthedocs.org/user_builds/pyautolens/envs/latest/lib/python3.12/site-packages/numpy/__init__.py'>)

Calculate the intensity of the cored-Sersic light profile on a grid of radial coordinates.

Parameters:

grid_radii (ndarray) – The radial distance from the centre of the profile. for each coordinate on the grid.

convergence_func(grid_radius, xp=<module 'numpy' from '/home/docs/checkouts/readthedocs.org/user_builds/pyautolens/envs/latest/lib/python3.12/site-packages/numpy/__init__.py'>)

Returns the convergence of the mass profile as a function of the radial coordinate.

This is used to integrate the convergence profile to compute enclosed masses and the Einstein radius.

Parameters:

grid_radius (float) – The radial distance from the profile centre at which the convergence is evaluated.

Returns:

The convergence at the input radial distance.

Return type:

float

intensity_prime(xp=<module 'numpy' from '/home/docs/checkouts/readthedocs.org/user_builds/pyautolens/envs/latest/lib/python3.12/site-packages/numpy/__init__.py'>)

Overall intensity normalisation in the rescaled Core-Sersic light profiles (electrons per second)