Error sources in SLODAR turbulence profile fitting

Adapting to the Atmosphere Conference 2014

物理学;地球科学

Butterley, Tim^1 ; Osborn, James^1 ; Wilson, Richard^1

Centre for Advanced Instrumentation, Department of Physics, Durham University, South Road, Durham

DH1 3LE, United Kingdom^1

关键词: Error sources;    Low wind speed;    Main error sources;    Outer scale;    Shack-Hartmann wavefront sensors;    Spatial covariance;    Temporal sampling;    Turbulence profile;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/595/1/012006/pdf
DOI  :  10.1088/1742-6596/595/1/012006

来源: IOP

【 摘 要 】

This paper discusses some of the main error sources that affect use of the Slope Detection and Ranging (SLODAR) technique to recover atmospheric turbulence profiles from Shack-Hartmann wavefront sensor data. The most significant factor we address here is that of temporal sampling - we examine the effect of poorly-averaged slope correlations due to low wind speeds (or data sets that are insufficiently long) on spatial covariances of wavefront slopes. We discuss how this can affect the observed outer scale of the turbulence. A dual SCIDAR- SLODAR instrument is described that is ideally suited to exploring the impact of these effects and, potentially, correcting them. Some preliminary results from the instrument are presented.