Selection of astrophysical/astronomical/solar sites at the Argentina East Andes range taking into account atmospheric components

Monte Carlo performance studies for the site selection of the Cherenkov Telescope Array

“…Site atmospheric models (density and refraction index as a function of the altitude) were generated using the NRLMSISE-00 model[21] and crosschecked against radiosonde data, where available near the sites. A total of 3 Northern and 6 Southern Hemisphere sites were simulated, all listed inTable 1, together with their altitudes and geomagnetic field strengths ([22,23]). Closely located site candidates: Yavapai and Meteor Crater in the US, Armazones and Paranal in Chile and Tenerife and La Palma in Spain have similar characteristics.…”

SO2 and Aerosol Evolution over the Very Clear Atmosphere at the Argentina Andes Range Sites of San Antonio de Los Cobres and El Leoncito

“…The atmosphere at the North and Central Argentinean Andes range is exceptionally clear and very adaptable for the placement of astrophysical/astronomical/solar observatories, as was shown by Piacentini et al [5], since the atmospheric components (gases and aerosols) are present in a very small proportion, with respect to many other places in the world where this type of observatories are placed. However, this region is part of the Pacific fire belt, composed of a large number of volcanoes, some of them very active.…”

“…In Table 2 percentages values of the total particle concentration (PM > 0.22) are presented for PM2.5, PM2.5-10, PM10 and PM > 10 fractions. In a previous work [5], we determined with the same GRIMM instrument, a total particle number concentration of (2800 ± 140) particles/cm 3 in SAC and of (5860 ± 140) particles/cm 3 in LEO. The clearness of both skies is demonstrated, when compared with the definition of a clear atmosphere given by ISO 14644-1 Class 8 norm, that considers that the particle concentration for particulate matter larger than 5 microns (PM ≥ 5) must be not larger than 29,300 particles/cm 3 .…”

“…• When compared with places around the world were astronomical/astrophysical/solar observatories are situated, the SAC and LEO sites are in the range of those with the lowest aerosol content [5], even if these sites are near active volcanoes. Another confirmation of this assessment is given by the volcanic dust database at the Servicio Meteorológico Nacional of Argentina, that in 5 years (2011-2016 period) informed of only one significant dust deposition event in San Juan Province (where the LEO site is located) and no dust deposition in Salta Province (where SAC is located, www.smn.gov.ar/vaac/buenosaires/cenizaenargentina.php ?lang=es).…”

Site analysis in the Argentinean Andean region for the placement of astrophysical observatories and solar photovoltaic power plants. The case of the “Leoncito 2” site

“…Two of these sites were located in the Argentinean Andean region: one near San Antonio de los Cobres (referred as SAC) in Salta province (24º02'43"S, 66º14'06"W, 3607m asl) and the other one near the Complejo AStronómico El LEOncito CASLEO (referred as LEO) in San Juan province (31º04'48"S,69º04'48"S, 2670m asl). Various studies have been performed to characterize the Argentinean candidates (Piacentini et al 2016, Maier G. et al, 2015, Allekote I., 2013, Otero L. et al, 2013. While the first studies were taking place, a third candidate was considered: an alternative site in the area of LEO, but at a lower altitude.…”