Bibcode
Morris, M. R.; Pérez-Garrido, A.; Rebolo, R.; Labadie, L.; Girard, J. H.; Ghez, A.; Yelda, S.; Schödel, R.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 429, Issue 2, p.1367-1375
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2
2013
Citations
46
Refereed citations
35
Description
We present a method for speckle holography that is optimized for crowded
fields. Its two key features are an iterative improvement of the
instantaneous point spread functions (PSFs) extracted from each speckle
frame and the (optional) simultaneous use of multiple reference stars.
In this way, high signal-to-noise ratio and accuracy can be achieved on
the PSF for each short exposure, which results in sensitive, high-Strehl
reconstructed images. We have tested our method with different
instruments, on a range of targets, and from the N[10 μm] to the
I[0.9 μm] band. In terms of PSF cosmetics, stability and Strehl
ratio, holographic imaging can be equal, and even superior, to the
capabilities of currently available adaptive optics (AO) systems,
particularly at short near-infrared to optical wavelengths. It
outperforms lucky imaging because it makes use of the entire PSF and
reduces the need for frame selection, thus, leading to higher Strehl and
improved sensitivity. Image reconstruction a posteriori, the possibility
to use multiple reference stars and the fact that these reference stars
can be rather faint means that holographic imaging offers a simple way
to image large, dense stellar fields near the diffraction limit of large
telescopes, similar to, but much less technologically demanding than,
the capabilities of a multiconjugate AO system. The method can be used
with a large range of already existing imaging instruments and can also
be combined with AO imaging when the corrected PSF is unstable.
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Very Low Mass Stars, Brown Dwarfs and Planets
Our goal is to study the processes that lead to the formation of low mass stars, brown dwarfs and planets and to characterize the physical properties of these objects in various evolutionary stages. Low mass stars and brown dwarfs are likely the most numerous type of objects in our Galaxy but due to their low intrinsic luminosity they are not so
Rafael
Rebolo López