autogalaxy.profiles.light.operated.Moffat#

Bases: Moffat, LightProfileOperated

The elliptical Moffat light profile, which is commonly used to model the Point Spread Function of Astronomy observations.

This form of the MOffat profile is a reparameterizaiton of the original formalism given by https://ui.adsabs.harvard.edu/abs/1969A%26A…..3..455M/abstract. The actual profile itself is identical.

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).
alpha (float) – Scales the overall size of the Moffat profile and for a PSF typically corresponds to the FWHM / 2.
beta (float) – Scales the wings at the outskirts of the Moffat profile, where smaller values imply heavier wings and it tends to a Gaussian as beta goes to infinity.

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).
`blurred_image_2d_from`	Evaluate the light object's 2D image from a input 2D grid of coordinates and convolve it with a PSF.
`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
`has`	Returns True if any attribute of this profile is an instance of the input class cls, else False.
`image_2d_from`	Returns the Moffat light profile's 2D image from a 2D grid of Cartesian (y,x) coordinates.
`image_2d_via_radii_from`	Returns the 2D image of the Moffat light profile from a grid of coordinates which are the radial distance of each coordinate from the its centre.
`luminosity_integral`	Routine to integrate the luminosity of an elliptical light profile.
`luminosity_within_circle_from`	Integrate the light profile to compute the total luminosity within a circle of specified radius.
`padded_image_2d_from`	Evaluate the light object's 2D image from a input 2D grid of padded coordinates, where this padding is sufficient to encapsulate all surrounding pixels that will blur light into the original image given the 2D shape of the PSF's kernel.
`radial_grid_from`	Convert a grid of (y, x) coordinates, to their radial distances from the profile centre (e.g. :math: r = sqrt(x2 + y2)).
`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.
`unmasked_blurred_image_2d_from`	Evaluate the light object's 2D image from a input 2D grid of coordinates and convolve it with a PSF, using a grid which is not masked.
`visibilities_from`	Evaluate the light object's 2D image from a input 2D grid of coordinates and transform this to an array of visibilities using a autoarray.operators.transformer.Transformer object and therefore a Fourier Transform.

Attributes

`coefficient_tag`	A short string tag used to label the intensity coefficient when this profile is used inside a Basis object (e.g. for multi-Gaussian expansion or shapelet decomposition).
`half_light_radius`	The radius that contains half of the total light of the profile (the half-light radius).