Short term minutes-time scale temporal variation statistics of sodium layer dynamics

TL;DR

This paper analyzes short-term sodium layer dynamics on a minute scale to understand their impact on laser guide star brightness, using lidar measurements to provide valuable statistical insights.

Contribution

It presents the first detailed statistical analysis of sodium layer variability on a minute time scale based on lidar data, aiding adaptive optics performance assessment.

Findings

Sodium layer brightness varies significantly on a minute scale.

Sodium mean height shows notable short-term fluctuations.

Statistical models of sodium dynamics can improve laser guide star calibration.

Abstract

The brightness and height of the sodium laser guide star of adaptive optics could vary significantly due to the temporal dynamics of sodium column density and the mean height of sodium layer. To measure these dynamics, an independent sodium Lidar is a necessity. Without such an instrument, it is almost impossible to discern the cause of the brightness variation of laser guide star from the sodium layer's dynamics or other factors from the laser itself. For applications such as characterizing the performance of sodium laser for sodium laser guide star generation, minutes scale short term statistics of the sodium layers' abundance and height is extremely helpful for estimating the contribution of sodium layer's variation to the variation of laser guide star's brightness. In this paper, we analyzed our previous measurement of sodium layer dynamics that has been gathered in two winters, and presented the temporal variation statistics of sodium column density and mean height within minute time scale based on our measurements.