Simulation Studies of the Backscattering Signal in HSRL Technique

TL;DR

This paper combines laboratory experiments and simulations to analyze backscattering signals in HSRL, improving atmospheric monitoring techniques relevant for UHECR observatories by comparing simulated and experimental data.

Contribution

It presents a novel simulation and experimental comparison of backscattering signals in HSRL using specific laboratory setups and atmospheric models.

Findings

Simulated and experimental fringe images show good agreement.

Backscattering at 2000 m altitude was effectively modeled.

Beam diameter influences fringe image characteristics.

Abstract

The technique of High Spectral Resolution Lidar (HSRL) for atmospheric monitoring allows the determination of the aerosol to molecular ratio and can be used in UHECR Observatories using air fluorescence telescopes. By this technique a more accurate estimate of the Cherenkov radiation superimposed to the fluorescence signal can be achieved. A laboratory setup was developed to determine the backscattering coefficients using microparticles diluted in water and diffusion interfaces. In this setup we used a CW SLM laser at 532 nm and a 250 mm Newtonian telescope. Simulations of the above experimental configuration have been made using Scatlab\c{opyright}, FINESSE\c{opyright} 0.99.8 and MATLAB\c{opyright} and are presented in this work. We compare the simulated 2-dimensional Fabry-Perot fringe images of the backscattering signal recorded in the CCD sensor with that of experimental ones. Additionally, we simulated the backscattering of the laser beam by the atmosphere at a height of 2000 m and we have studied the influence of the beam and its diameter on the fringe image.