Large Scale 3D Image Reconstruction in Optical Interferometry
arXiv:1503.01565
Abstract
Astronomical optical interferometers (OI) sample the Fourier transform of the intensity distribution of a source at the observation wavelength. Because of rapid atmospheric perturbations, the phases of the complex Fourier samples (visibilities) cannot be directly exploited , and instead linear relationships between the phases are used (phase closures and differential phases). Consequently, specific image reconstruction methods have been devised in the last few decades. Modern polychromatic OI instruments are now paving the way to multiwavelength imaging. This paper presents the derivation of a spatio-spectral ("3D") image reconstruction algorithm called PAINTER (Polychromatic opticAl INTErferometric Reconstruction software). The algorithm is able to solve large scale problems. It relies on an iterative process, which alternates estimation of polychromatic images and of complex visibilities. The complex visibilities are not only estimated from squared moduli and closure phases, but also from differential phases, which help to better constrain the polychromatic reconstruction. Simulations on synthetic data illustrate the efficiency of the algorithm.
EUSIPCO, Aug 2015, NICE, France
References in corpus (8)
- PURIFY: a new approach to radio-interferometric imaging
- The application of compressive sampling to radio astronomy I: Deconvolution
- Imaging the spinning gas and dust in the disc around the supergiant A[e] star HD62623
- Sparsity Averaging for Compressive Imaging
- Monte-Carlo Imaging for Optical Interferometry
- Exploiting spatial sparsity for multi-wavelength imaging in optical interferometry
- PAINTER: a spatio-spectral image reconstruction algorithm for optical interferometry
- Tensor optimisation for optical-interferometric imaging