White-light interferometry using a channeled spectrum. I. General models and fringe estimation algorithms.

Area of Science:

• Astronomy and Astrophysics
• Optical Engineering

Background:

• Astrometric measurements using stellar interferometry require precise determination of optical path-length differences.
• Dispersion in optical systems causes wavelength-dependent path-length differences, complicating astrometric signature extraction.
• Broad spectral channels in standard approaches limit accuracy, as monochromatic models are insufficient.

Purpose of the Study:

• To develop a robust and precise method for astrometric measurements in stellar interferometry that accounts for spectral dispersion.
• To introduce a new class of models with few spectral and dispersion parameters for phase estimation.
• To derive a phase-shifting interferometry algorithm tailored to the new model structure.

Main Methods:

• Development of a new class of models incorporating spectral and dispersion parameters.
• Derivation of a phase-shifting interferometry algorithm exploiting the model structure.
• Numerical simulations to test the robustness and precision of the proposed approach.

Main Results:

• The proposed models effectively handle spectral dispersion in astrometric measurements.
• The derived phase-shifting algorithm demonstrates robustness and precision.
• Numerical examples validate the effectiveness of the approach for phase estimation.

Conclusions:

• The new modeling approach offers a significant improvement for astrometric measurements in stellar interferometry.
• Accurate phase estimation in the presence of dispersion is achievable with the proposed method.
• This technique enhances the precision of astronomical observations relying on stellar interferometry.