EDP Sciences
Free access
Volume 429, Number 2, January II 2005
Page(s) 747 - 753
Section Instruments, observational techniques, and data processing
DOI http://dx.doi.org/10.1051/0004-6361:20040270

A&A 429, 747-753 (2005)
DOI: 10.1051/0004-6361:20040270

Sensitivity of a "dispersed-speckles" piston sensor for multi-aperture interferometers and hypertelescopes

V. Borkowski1, 2, A. Labeyrie1, F. Martinache1 and D. Peterson3

1  Collège de France & Laboratoire d'Interférométrie Stellaire et Exo-planétaire LISE-Observatoire de Haute-Provence - CNRS, 04870 Saint-Michel l'Observatoire, France
    e-mail: borkowski@obs-hp.fr
2  Alcatel Space Industries, 100 bd du Midi, BP 99, 06156 Cannes la Bocca Cedex, France
3  Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800, USA

(Received 13 February 2004 / Accepted 2 September 2004)

In multi-aperture interferometers and hypertelescopes, the piston errors can be determined from multi-spectral images of the speckle pattern using a 3-dimensional Fourier transform. We study the limiting magnitude of the method in the case of non-redundant apertures using analytical derivations and numerical simulations. We show specifically for the case of sub- r0 apertures that a few photons per aperture within the full spectral bandwidth will suffice to measure piston errors. The method's sensitivity is thus comparable to that of the Shack-Hartmann and other methods used with monolithic apertures.

Key words: turbulence -- techniques: interferometric -- atmospheric effects

© ESO 2004