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arXiv · 0807.2001

Fringe tracking and spatial filtering: phase jumps and dropouts

David F. Buscher·John S. Young·Fabien Baron·Christopher A. Haniff
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Abstract

Fringe tracking in interferometers is typically analyzed with the implicit assumption that there is a single phase associated with each telescope in the array. If the telescopes have apertures significantly larger than r0 and only partial adaptive optics correction, then the phase measured by a fringe sensor may differ significantly from the "piston" component of the aperture phase. In some cases, speckle noise will cause "branch points" in the measured phase as a function of time, causing large and sudden jumps in the phase. We present simulations showing these effects in order to understand their implications for the design of fringe tracking algorithms.

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David F. Buscher, John S. Young, Fabien Baron, Christopher A. Haniff. 2008-07-12. Fringe tracking and spatial filtering: phase jumps and dropouts. https://doi.org/10.1117/12.789869

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