THE TEMPERATURE EFFECT IN SECONDARY COSMIC RAYS (MUONS) OBSERVED AT THE GROUND: ANALYSIS OF THE GLOBAL MUON DETECTOR NETWORK DATA

Author(s):Show less -

de Mendonca, R. R. S. ; Braga, C. R. ; Echer, E. ; Dal Lago, A. ; Munakata, K. ; Kuwabara, T. ; Kozai, M. ; Kato, C. ; Rockenbach, M. ; Schuch, N. J. ; Al Jassar, H. K. ; Sharma, M. M. ; Tokumaru, M. ; Duldig, M. L. ; Humble, J. E. ; Evenson, P. ; Sabbah, I.

• Document type: Journal article
• Source: ASTROPHYSICAL JOURNAL; v. 830, n. 2 OCT 20 2016.
• Web of Science Citations: 3

Abstract

The analysis of cosmic ray intensity variation seen by muon detectors at Earth's surface can help us to understand astrophysical, solar, interplanetary and geomagnetic phenomena. However, before comparing cosmic ray intensity variations with extraterrestrial phenomena, it is necessary to take into account atmospheric effects such as the temperature effect. In this work, we analyzed this effect on the Global Muon Detector Network (GMDN), which is composed of four ground-based detectors, two in the northern hemisphere and two in the southern hemisphere. In general, we found a higher temperature influence on detectors located in the northern hemisphere. Besides that, we noticed that the seasonal temperature variation observed at the ground and at the altitude of maximum muon production are in antiphase for all GMDN locations (low-latitude regions). In this way, contrary to what is expected in high-latitude regions, the ground muon intensity decrease occurring during summertime would be related to both parts of the temperature effect (the negative and the positive). We analyzed several methods to describe the temperature effect on cosmic ray intensity. We found that the mass weighted method is the one that best reproduces the seasonal cosmic ray variation observed by the GMDN detectors and allows the highest correlation with long-term variation of the cosmic ray intensity seen by neutron monitors. (AU)

• FAPESP's process: 13/03530-0 - 1D and 2D analysis of geomagnetic storms precursors using the Gobal muon detector network data
• Grantee: Rafael Rodrigues Souza de Mendonça
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 12/20594-0 - 1D and 2D analysis of geomagnetic storms precursors using the Gobal Muon Detector Network data
• Grantee: Rafael Rodrigues Souza de Mendonça
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 14/24711-6 - Study of coronal mass ejections and its corresponding interplanetary structures near the Earth
• Grantee: Carlos Roberto Braga
• Support Opportunities: Scholarships in Brazil - Post-Doctoral