Issue |
Astron. Astrophys. Suppl. Ser.
Volume 144, Number 1, May II 2000
|
|
---|---|---|
Page(s) | 39 - 44 | |
DOI | https://doi.org/10.1051/aas:2000197 | |
Published online | 15 May 2000 |
Optical parameters relevant for High Angular Resolution at Paranal from GSM instrument and surface layer contribution
1
U.M.R. Astrophysique No. 6525, Université de Nice–Sophia Antipolis, F–06108 Nice Cedex 2, France
2
Sternberg Astronomical Institute, Universitestsky prosp. 13, 119899 Moscow, Russia
3
European Southern Observatory, Karl–Schwarzschild–Str. 2, D–85748 Garching bei München, Germany
Send offprint request to: F. Martin, e-mail: Francois.MARTIN@unice.fr
Received:
12
January
2000
Accepted:
25
February
2000
Main atmospheric parameters characterizing the turbulence were
measured at the Paranal ESO Observatory (Chile) with the
Generalized Seeing Monitor (GSM) during 19 nights in
November–December 1998. The median seeing for this period was
, a little worse than average, the spatial coherence
outer scale of the wavefront
m and the median
isoplanatic angle
. A very good agreement with
seeing values given by ESO DIMM was found. Effects of ground layer
turbulence were estimated from measurements of temperature
micro–fluctuations at several altitudes. These measurements
revealed that the first 21 m above ground account for 12.5%
of the total turbulent energy. Comparison between GSM and ESO DIMM
values have permitted to highlight a local phenomenon which occurs
sometimes at the site in the middle of the night. Statistics of
the refractive index structure constant
in the surface
layer is also studied.
Key words: turbulence / atmospheric effects / site testing
© European Southern Observatory (ESO), 2000