First cosmic-ray measurements by the SciCRT solar neutron experiment in Mexico

Abstract

The SciBar Cosmic Ray Telescope (SciCRT) is a new multi-purpose cosmic-ray detector. Its main aim is the measurement of solar neutrons to investigate the ion acceleration process during solar flares. We installed the SciCRT at the Instituto Nacional de Astrofisica, Óptica y Electrónica (INAOE) in eastern Mexico. We had two cosmic-ray observation campaigns at the place in November 2012 and February 2013 using 5/8 of the complete detector. The detector was transferred to the top of Mt. Sierra Negra, 4600m above sea level, in April 2013.The results obtained at INAOE, and the first experimental result at the mountain are presented in this paper. The counting rates of experimental data and Monte Carlo simulation (MC) are 409.3 (±0.1)Hz and 395.2 (±4.8)Hz, respectively. The data and the MC do not show a big discrepancy. The percentages of hadronic shower events in the data and MC are 0.15 (±0.02)% and 0.16 (±0.03)%, respectively. The corresponding percentages of electromagnetic shower events are 0.16 (±0.02)% and 0.18 (±0.03)%. In this case data and MC calculations are in reasonable agreement. The effective area and expected time profile of solar neutrons obtained by the SciCRT are calculated using MC.