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arXiv · 2607.08289

Development of a Raman Lidar for the Southern Site of the Cherenkov Telescope Array Observatory

Patrick Brun·Omar Gabella·Stephane Rivoire·George Vasileiadis
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Abstract

The future CTAO will reach a sensitivity and energy resolution never obtained until now by any other high-energy gamma-ray experiment. Studying the atmospheric conditions during the CTAO observations, namely the extinction and backscatter coefficients, permits a very precise evaluation of the atmospheric UV absorption, a parameter that directly affects the energy and flux spectra of the CTAO-studied sources. This paper describes the motivation for the LUPM Raman Lidar system, a Lidar specifically designed to fulfill the CTAO requirements for the south site in Chile. Preliminary results obtained during a two-year campaign at the OHP Observatory are presented. Our results include estimations of the extinction, back-scatter, and Lidar ratio at both 355 and 532 nm and confirm the conformity of our prototype to the CTAO requirements

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Patrick Brun, Omar Gabella, Stephane Rivoire, George Vasileiadis. 2026-07-09. Development of a Raman Lidar for the Southern Site of the Cherenkov Telescope Array Observatory. https://arxiv.org/abs/2607.08289

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