A novel LIDAR-based Atmospheric Calibration Method for Improving the   Data Analysis of MAGIC
  A new method for analyzing the returns of the custom-made 'micro'-LIDAR system, which is operated along with the two MAGIC telescopes, allows to apply atmospheric corrections in the MAGIC data analysis chain. Such corrections make it possible to extend the effective observation time of MAGIC under adverse atmospheric conditions and reduce the systematic errors of energy and flux in the data analysis. LIDAR provides a range-resolved atmospheric backscatter profile from which the extinction of Cherenkov light from air shower events can be estimated. Knowledge of the extinction can allow to reconstruct the true image parameters, including energy and flux. Our final goal is to recover the source-intrinsic energy spectrum also for data affected by atmospheric extinction from aerosol layers, such as clouds. 
Christian Fruck, Markus Gaug, Roberta Zanin, Daniela Dorner, Daniel   Garrido, Razmik Mirzoyan, Lluis Font (for the MAGIC Co...
astro-ph.IM