Arcetri Analytical Tools for Multi-Conjugate Adapive Optics systems

Fourier

IDL file in OAA library: oaa_lib/ao_lib/mcao_fourier.pro

• Approximate estimation of HO tomo., gen. fitting, temporal error, noise error
• Approximations: infinite pupil, point-like source, cone effect not accurately modeled
• Can be used to produce PSFs (short or long exposure)

References:

• Computation of the tomographic error from Neichel 2009: Fourier analysis for WFAO.
• Computation of the fitting error inspired from Tokovinin 2000: Isoplanatism in MCAO.

Dedicated generalized fitting

IDL file in OAA library: oaa_lib/ao_lib/gen_fitting.pro

• same as in Fourier code but much faster, useful if we want to compute this error only (approx.: perfect tomography)

References:

• Rigaut 2000: Principles, limitations and performance of MCAO (default computation)
• Tokovinin 2000: Isoplanatism in MCAO (alternative computation)

Zernike covariance

IDL file in OAA library: oaa_lib/ao_lib/zern_cov_aniso.pro

• Computes the covariance of turbulent Zernike modes from 2 different beams
• Can also compute the temporal PSD corresponding to this covariance (to be corrected soon, the formula in the code is right, but corresponds to a particular case)

References:

• Whiteley 1998

IIR filter optimization

IDL file in OAA library: oaa_lib/tfl_lib/modal_control_optimization.pro

• optimizes the temporal filter to apply to an input temporal PSD (given the order of the filter and gains to explore).

References:

• Agapito et al. SPIE (2012)

Pixel mean and variance

IDL file in OAA library: oaa_lib/ao_lib/meanvar_pixel_thr.pro

• computes the mean and variance of a pixel value given the mean flux received, the RON, the background, the dark current, the excess noise factor and a threshold applied on pixels.

WCoG variance and bias

IDL file in OAA library: oaa_lib/ao_lib/calc_noise_wcog.pro

• computes the variance and bias of a slope computed with a WCoG, given a weighting map, a PSF (default: Gaussian spot) and the noise conditions. It uses the code meanvar_pixel_thr.pro.

Sky coverage

• Creation of a catalog of fields and valid asterisms from a star list (given by TRILEGAL for example), taking into account the geometry of the technical FoV and the pick-off mirrors.
• Estimation of LO residuals in any direction of the field for a given NGS asterism, computing the tomographic error (from Zernike covariance code), the noise error (interpolation from E2E) and the windshake error (from PSD and transfer function).
• Computation of tip/tilt kernel maps, distorsions due to WFSs’ pointing error.

References:

• Plantet et al. SPIE (2018)
• Plantet et al. AO4ELT6 (2019)

-- CedricPlantet - 04 Dec 2019