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Results from the GMT Ground-Layer Experiment at the Magellan Telescopes

A. Athey·S. Shectman·M. Phillips·J. Thomas-Osip
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Abstract

We present results from our two year study of ground-layer turbulence as seen through the 6.5-meter Magellan Telescopes at Las Campanas Observatory. The experiment consists of multiple, moderate resolution, Shack-Hartmann wavefront sensors deployed over a large 16 arcminute field. Over the two years of the experiment, the ground-layer turbulence has been sampled on eleven nights in a variety of seeing and wind conditions. On most nights the ground-layer turbulence contributes 10% to the total visible-band seeing, although a few nights exhibit ground-layer contributions up to 30%. We present the ground-layer turbulence on the sampled nights as well as a demonstration of its strength as a function of field size. This information is combined with data from a MASS-DIMM seeing monitor adjacent to the Magellan Telescopes to infer the annual ground-layer contribution to seeing at Las Campanas.

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A. Athey, S. Shectman, M. Phillips, J. Thomas-Osip. 2006-06-13. Results from the GMT Ground-Layer Experiment at the Magellan Telescopes. https://doi.org/10.1117/12.672276

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