Muons recorded in the Soudan 2 underground nucleon decay detector from January 1989 to February 1991 have been examined for any correlation with the radio flares of Cygnus X-3 observed during this period. On two nearby days during the radio flare of January 1991 a total of 32 muons within 2.0° of the Cygnus X-3 direction were observed when 11.4 were expected.
Bibliographical noteFunding Information:
This work was undertaken with the support of the UK Science and Engineering Research Council, the University of Oxford, the US Department of Energy and the State of Minnesota. We wish to thank: the staff of the collaborating laboratories, the Minnesota Department of Natural Resources for allowing us to use the facilities of the Tower-Soudan State Park, the staff of the park for their day to day support, Messrs. B. Anderson, J. Beaty, G. Benson, D. Carlson, B. Dahlin, J. Eininger and J. Meier of the Soudan Mine Crew for their work in the installation of the experiment, the