Impact of H.E.S.S. Lidar profiles on Crab Nebula data

TL;DR

This paper demonstrates how H.E.S.S. lidar profiles improve gamma-ray data analysis by reducing atmospheric uncertainties, leading to more accurate measurements of the Crab Nebula spectrum.

Contribution

It introduces the use of atmospheric lidar profiles to correct for atmospheric effects in gamma-ray observations, enhancing data accuracy.

Findings

Improved Crab Nebula spectrum measurement with lidar data

Reduction of systematic errors in atmospheric modeling

Enhanced accuracy in photon energy and flux estimation

Abstract

The H.E.S.S. experiment in Namibia is a high-energy gamma-ray telescope sensitive in the energy range from 30 GeV to a several tens of TeV, that uses the atmospheric Cherenkov technique to detect showers developed within the atmosphere. The elastic lidar, installed on the H.E.S.S. site, allows to reduce the systematic errors related to the atmospheric composition uncertainties thanks to the estimation of the extinction profile for the Cherenkov light (300-650 nm). The latter has a direct impact on the reconstructed parameters, such as the photon energy and the source flux. In this paper we report on physics results obtained on the Crab Nebula spectrum using the lidar profiles obtained at the H.E.S.S. site.