2017/09/13 by Laura Valore, C. Aramo, Valore, Laura +23
Earth and Planetary Sciences · Environmental Science · Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Atmospheric Ozone and Climate #Atmospheric aerosols and clouds #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Instrumentation and Methods for Astrophysics (astro-ph.IM)
paper · pdf · doi:10.48550/arxiv.1709.04246
openalex publication_date 2017/09/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The CTA is the next generation of ground based very high energy gamma ray\nImaging Atmospheric Cherenkov Telescopes. Since observations with this\ntechnique are affected by atmospheric conditions, an accurate knowledge of the\natmospheric properties is fundamental to improve the precision and duty cycle\nof the CTA. Measurements of absorption and scattering properties of the\natmosphere due to aerosols and molecules can be used in the event\nreconstruction or in MODTRAN, an analytical code designed to model the\npropagation of electromagnetic radiation. MODTRAN output is used as an input\nfor the air shower simulation and Cherenkov light production, giving the\noptical depth profiles that together with the refractive index allow the proper\nsimulation of the gamma ray induced signals and a correct measurement of the\nprimary energy from the detected signals. The ARCADE Raman Lidar will be used\nfor the on site characterization of the aerosol attenuation profiles of the UV\nlight. The collected data will be used in preparation for the full operation of\nthe array, providing nightly information about the aerosol properties such as\nthe vertical aerosol optical depth and the water vapour mixing ratio with an\naltitude resolution better than 100 m from about 400 m to 10 km above ground\nlevel. These measurements will help to define the needs for Monte Carlo\nsimulations of the shower development and of the detector response. This\ninstrument will also be used for the intercalibration of the future Raman\nLidars that are expected to operate at the CTA sites. This contribution\nincludes a description of the ARCADE Lidar and the characterization of the\nperformance of the system. The system is expected to be shipped to the northern\nsite of the CTA (La Palma) before the end of 2017, to acquire data locally for\n1 year before being moved to the southern site (Chile).\n