Optimum synthetic-aperture imaging of extended astronomical objects

Area of Science:

• Astronomy and Astrophysics
• Optical Interferometry
• Image Reconstruction

Background:

• Optical aperture-synthesis imaging is crucial for high-resolution astronomical observation.
• Common beam combination strategies include coaxial Michelson interferometers and multiaxial interferometers.
• Novel approaches like densified pupil imaging and wide field-of-view (FOV) coaxial imaging are emerging.

Purpose of the Study:

• To develop a unified mathematical framework for comparing different optical aperture-synthesis imaging configurations.
• To analyze and contrast the resolution and noise sensitivity of four distinct beam combination strategies.
• To evaluate the performance of these techniques for interferometric synthetic aperture, wide-FOV imaging.

Main Methods:

• Development of a common mathematical formulation for comparing imaging techniques.
• Application of singular value decomposition (SVD) for performance analysis.
• Evaluation of resolution and signal-to-noise ratio (SNR) behaviors across configurations.

Main Results:

• Identified clear performance differences between the four compared telescope configurations.
• Demonstrated distinct signal-to-noise ratio behaviors for each imaging approach.
• Quantified the trade-offs in resolution and sensitivity for different beam combination strategies.

Conclusions:

• The choice of beam combination strategy significantly impacts imaging performance for stellar objects.
• Mathematical formulation and SVD provide effective tools for comparing interferometric imaging techniques.
• Future astronomical imaging systems can benefit from tailored configuration selection based on specific scientific goals.