R. Ticona

ALPAQUITA Array in the ALPACA Project

We are now proposing a new project which consists of a large air shower array (83,000 m^2) and a muon detector array (5,400 m^2) located at the altitude of 4,740 m near La Paz in Bolivia to observe 100 TeV gamma rays in the southern sky. The ALPAQUITA array is a prototype air shower array which will be constructed at the ALPACA site. This array consists of 45 scintillation counters of 1 m^2 in area each, and its effective area is approximately 8,000 m^2 (1/10 of ALPACA air shower array). In the present paper, we report on the current status and the performance of the ALPAQUITA array

Status of LAGO at mount Chacaltaya

The Latin American Giant Observatory (LAGO) is an international experiment with multiple scientific objectives. These objectives include the study of the extreme universe, space weather and atmospheric radiation at ground level. The observatory is composed of several experimental sites, distributed in the American continent, from Argentina to Mexico. The highest LAGO site is located on the Chacaltaya mountain, Bolivia, at an altitude of nearly 5300 m.a.s.l. In this document we report the status of the experimental site on Chacaltaya. In particular, emphasis is given on the development of a water Cherenkov detector. We describe the pilot detector that we are assembling, the energy calibration method and the characterization of the PMT employed.

The overview of the ALPACA Experiment

The ALPACA experiment is a new project aimed at wide field-of-view high-sensitivity observations of high-energy cosmic rays and cosmic gamma rays, launched between Bolivia and Japan in 2016. It is composed of an 83,000 m

Analysis of Background Cosmic Ray Rate in the 2010-2012 Period from the LAGO-Chacaltaya Detectors

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Combination of emulsion chamber and air shower array at Mt. Chacaltaya

air shower array and a 5,400 m

Solar Neutron Event in Association with a Large Solar Flare on August 25, 2001

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Search for solar neutrons associated with proton flares in solar cycle 23

underground muon detector array, on a highland at the altitude of 4,740 m, halfway up Mount Chacaltaya on the outskirts of La Paz, Bolivia.

New Experiment on the Observation of Solar Neutrons at Chacaltaya

Bariloche, S.C. de Bariloche, Argentina. 2 Sede Andina, Universidad Nacional de Río Negro, S.C. de Bariloche, Argentina. 3 Escuela de Física, Universidad Industrial de Santander, Bucaramanga, Colombia. 4 Centro de Física Fundamental, Dept. de Física, Universidad de Los Andes, Mérida Venezuela 5 Instituto de Investigaciones Físicas, Universidad Mayor de San Andrés, La Paz, Bolivia 6 lagoproject.org, see the full list of members and institutions at lagoproject.org/collab.html

Search for solar neutrons associated with series of X-class flares during the declining period of solar cycle 23, Paper 191

Data of 34 familes with the accompanying air showers, observed by the combination of emulsion chamber and air shower array at Mt. Chacaltaya, are presented. Comparison with the simulation calculation concludes that a change is necessary in the characteristics of hadron interactions in E0≥1015 eV.