Using 5.33 x 10(6) single muons collected in 1.46 x 10(4) live hours by MACRO during the period 1991-1994, we have searched for a correlation between variations in the underground muon rate, N-mu, and seasonal temperature variations in the atmosphere. These correlations are found to be present with high statistical significance. Analysis of the relatively complete December 1992-December 1994 subset of the data yields a value for the temperature coefficient, alpha(T) = (T/N-mu)(partial derivative N-mu/partial derivative T) = 0.83 +/- 0.13. Analysis of the total data Set gives consistent results. We have compared this result with the hypothesis that the muons observed in MACRO come from pion decays alone. Although our result is consistent with the 'pion only' hypothesis, a discussion of the sensitivity of our data sample to the kaon component of the cascades leading to observed muons underground will also be presented.
|Titolo:||Seasonal variations in the underground muon intensity as seen by MACRO|
|Data di pubblicazione:||1997|
|Digital Object Identifier (DOI):||10.1016/S0927-6505(97)00011-X|
|Appare nelle tipologie:||1.1 Articolo in rivista|