Performance of the INFN Camera calibration device of the first Large Size Telescope in the Cherenkov Telescope Array

TL;DR

This paper evaluates the calibration system of the first Large Size Telescope in the CTA, demonstrating its ability to achieve uniform calibration across a wide dynamic range during initial commissioning.

Contribution

It presents the performance assessment of the LST-1 camera calibration system (CaliBox) during early commissioning, including preliminary flat field measurements.

Findings

Calibration system achieves uniformity over large dynamic range

Preliminary flat field measurements indicate effective calibration

System performance supports accurate energy reconstruction

Abstract

On October $10^{\rm th}$ 2018 started the commissioning of the first Large Size Telescope (LST) prototype at the Cherenkov Telescope Array (CTA) northern site at the Observatorio del Roque de los Muchachos, Canary Island of La Palma (Spain). For a precise event energy reconstruction, an LST camera requires a uniform and constant calibration over a large dynamic range, up to $10^{4}$ photo-electrons (p.e.), for each camera photomultiplier tube (PMT). This paper describes the performance of the LST-1 camera calibration system (named CaliBox) in the first commissioning period and provides preliminary results of measurements of the light flat field