Light Profiles#

Standard [ag.lp]#

Standard parametric light profiles whose intensity is a free parameter of the model.

Gaussian

The elliptical Gaussian light profile.

GaussianSph

The spherical Gaussian light profile.

GaussianMultipole

The elliptical Gaussian light profile with m=3 and m=4 Fourier multipole perturbations on the eccentric radius.

Sersic

The elliptical Sersic light profile.

SersicSph

The spherical Sersic light profile.

SersicMultipole

The elliptical Sersic light profile with m=3 and m=4 Fourier multipole perturbations on the eccentric radius.

Exponential

The elliptical exponential profile.

ExponentialSph

The spherical exponential profile.

DevVaucouleurs

The elliptical Dev Vaucouleurs light profile.

DevVaucouleursSph

The spherical Dev Vaucouleurs light profile.

SersicCore

The elliptical cored-Sersic light profile.

SersicCoreSph

The elliptical cored-Sersic light profile.

ExponentialCore

The elliptical cored-Exponential light profile.

ExponentialCoreSph

The elliptical cored-Exponential light profile.

Chameleon

The elliptical Chameleon light profile.

ChameleonSph

The spherical Chameleon light profile.

ElsonFreeFall

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).

ElsonFreeFallSph

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).

Linear [ag.lp_linear]#

Linear light profiles whose intensity is not a free parameter but is instead solved analytically via a linear matrix inversion during each likelihood evaluation. This allows many profiles to be combined efficiently without exploding the non-linear parameter space.

Gaussian

The elliptical Gaussian light profile.

GaussianSph

The spherical Gaussian light profile.

GaussianMultipole

The linear elliptical Gaussian light profile with m=3 and m=4 Fourier multipole perturbations on the eccentric radius.

Sersic

The elliptical Sersic light profile.

SersicSph

The spherical Sersic light profile.

SersicMultipole

The linear elliptical Sersic light profile with m=3 and m=4 Fourier multipole perturbations on the eccentric radius.

Exponential

The elliptical Exponential light profile.

ExponentialSph

The spherical Exponential light profile.

DevVaucouleurs

The elliptical DevVaucouleurs light profile.

DevVaucouleursSph

The spherical DevVaucouleurs light profile.

SersicCore

The elliptical cored-Sersic light profile.

SersicCoreSph

The spherical cored-Sersic light profile.

ExponentialCore

The elliptical cored-Exponential light profile.

ExponentialCoreSph

The spherical cored-Exponential light profile.

Operated [ag.lp_operated]#

Operated light profiles that represent emission which has already had an instrument operation (e.g. PSF convolution) applied to it. The operated_only parameter on fitting classes controls whether these profiles are included or excluded from a given image computation.

Gaussian

The elliptical Gaussian light profile.

Moffat

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

Sersic

The elliptical Sersic light profile.

Basis [ag.lp_basis]#

A Basis groups a collection of light profiles (e.g. a Multi-Gaussian Expansion or shapelet decomposition) so that they behave as a single profile in the model. When the constituent profiles are LightProfileLinear instances their intensities are all solved simultaneously via a single inversion.

Basis

A basis is a collection of multiple light or mass profiles that are used to represent the light or mass distribution of a galaxy.