A dedicated tool for a full 3D C2N investigation

Abstract

In this contribution we present how the mesoscale model Meso-Nh model together with the Astro-Meso-Nh and a set of diagnostic tools allow for a full 3D investigation of the C²_<i>N</i> and derived integrated astroclimatic parameters. The possibility to study simultaneously 3D fields of meteorological and astroclimatic parameters permits us to provide a comprehensive understanding of the characteristics of the atmospheric flow as well as the physical mechanisms that produce them. To illustrate the different diagnostics and their potentialities, we investigated one night and looked at instantaneous fields of meteorologic and astroclimatic parameters. To show the potentialities of this tool for applications in an Observatory we ran the model above sites with very different optical turbulence (OT) distributions: the antarctic plateau (Dome C, Dome A, South Pole) and a mid-latitude site (Mt. Graham, Arizona). We put particular emphasis on the 2D maps of integrated astroclimatic parameters (such as seeing, isoplanatic angles, ...) and to the possibility to calculate them in different slabs (having what ever thickness) at different heights in the troposhere. The latter option is particularly useful for the seeing. For this reason this is an useful tool of prediction and investigation of the turbulence structure and it can support the optimization of the AO, GLAO and MCAO systems running at the focus of the ground-based telescopes. The examples we provide put clearly in evidence that different astroclimatic sites present different OT behaviors. Besides, our tool allowed us for discriminating these sites.