CN2 turbulent vertical distribution

Evolution of the turbulence profile for the night of 26th May 2006 at the ORM.
Description

The optical turbulence is caused by the fluctuations in the index of refraction of the air. The refractive-index structure constant of the turbulence, Cn2, is a measure of the turbulence strength (units of m-2/3) and depends on the wind and temperature vertical distributions.

Importance

The CN2 a key parameter for observing conditions, telescope design and for feasibility studies for adaptive optics.

The technique G-SCIDAR has proved to be the most efficient and reliable to retrieve CN2 profiles. The following figure shows the monthly statistical results of 140 nights of CN2 profiles obtained with this technique at the ORM.

Statistical monthly average (solid line) and median (dashed line) C<sub>N</sub><sup>2</sup> turbulence profiles at the ORM with G-SCIDAR measurements from 2004 to 2009.
Statistical monthly average (solid line) and median (dashed line) turbulence strength profiles at the ORM from a combination of 140 nights of G-SCIDAR measurements ranging between 2004 and 2009.
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