autogalaxy.profiles.light_profiles.SphSersicCore

class autogalaxy.profiles.light_profiles.SphSersicCore(centre: Tuple[float, float] = (0.0, 0.0), effective_radius: float = 0.6, sersic_index: float = 4.0, radius_break: float = 0.01, intensity_break: float = 0.05, gamma: float = 0.25, alpha: float = 3.0)
__init__(centre: Tuple[float, float] = (0.0, 0.0), effective_radius: float = 0.6, sersic_index: float = 4.0, radius_break: float = 0.01, intensity_break: float = 0.05, gamma: float = 0.25, alpha: float = 3.0)

The elliptical cored-Sersic light profile.

Parameters:
  • centre – The (y,x) arc-second coordinates of the profile centre.
  • effective_radius – The circular radius containing half the light of this profile.
  • sersic_index (Int) – Controls the concentration of the of the profile (lower value -> less concentrated, higher value -> more concentrated).
  • radius_break – The break radius separating the inner power-law (with logarithmic slope gamma) and outer Sersic function.
  • intensity_break – The intensity at the break radius.
  • gamma – The logarithmic power-law slope of the inner core profiles
  • alpha – Controls the sharpness of the transition between the inner core / outer Sersic profiles.

Methods

__init__(centre, float] = (0.0, 0.0), …) The elliptical cored-Sersic light profile.
blurred_image_2d_via_convolver_from(grid, …) Evaluate the light profile image on an input Grid2D of coordinates and then convolve it with a PSF using a Convolver object.
blurred_image_2d_via_psf_from(grid, …) Evaluate the light profile image on an input Grid2D of coordinates and then convolve it with a PSF.
cos_and_sin_to_x_axis() Determine the sin and cosine of the angle between the profile’s ellipse and the positive x-axis, counter-clockwise.
eta_u(u, coordinates)
from_axis_ratio_and_phi(centre, …)
grid_angle_to_profile(grid_thetas) The angle between each angle theta on the grid and the profile, in radians.
grid_to_eccentric_radii(grid) Convert a grid of (y,x) coordinates to an eccentric radius, which is (1.0/axis_ratio) * elliptical radius and used to define light profile half-light radii using circular radii.
grid_to_elliptical_radii(grid) Convert a grid of (y,x) coordinates to an elliptical radius.
grid_to_grid_cartesian(grid, radius) Convert a grid of (y,x) coordinates with their specified circular radii to their original (y,x) Cartesian coordinates.
grid_to_grid_radii(grid) Convert a grid of (y, x) coordinates to a grid of their circular radii.
image_1d_from(grid, Grid1D, …)
image_2d_from(grid, …) Calculate the intensity of the light profile on a grid of Cartesian (y,x) coordinates.
image_2d_via_radii_from(grid_radii) Calculate the intensity of the cored-Sersic light profile on a grid of radial coordinates.
luminosity_integral(x) Routine to integrate the luminosity of an elliptical light profile.
luminosity_within_circle(radius) Integrate the light profile to compute the total luminosity within a circle of specified radius.
profile_visibilities_via_transformer_from(…)
rotate_grid_from_reference_frame(grid) 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.
transform_grid_from_reference_frame(grid) Transform a grid of (y,x) coordinates from the reference frame of the profile to the original observer reference frame, including a rotation to its original orientation and a translation from the profile’s centre.
transform_grid_to_reference_frame(grid) Transform a grid of (y,x) coordinates to the reference frame of the profile, including a translation to its centre and a rotation to it orientation.

Attributes

angle
axis_ratio
cos_phi
elliptical_effective_radius The effective_radius of a Sersic light profile is defined as the circular effective radius.
half_light_radius
intensity_prime Overall intensity normalisation in the rescaled Core-Sersic light profiles (electrons per second).
phi_radians
sersic_constant A parameter derived from Sersic index which ensures that effective radius contains 50% of the profile’s total integrated light.
sin_phi