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Final results of magnetic monopole searches with the MACRO experiment

The MACRO Collaboration
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Abstract

We present the final results obtained by the MACRO experiment in the search for GUT magnetic monopoles in the penetrating cosmic radiation, for the range $4\times 10^{-5}< β< 1$. Several searches with all the MACRO sub-detectors (i.e. scintillation counters, limited streamer tubes and nuclear track detectors) were performed, both in stand alone and combined ways. No candidates were detected and a 90% Confidence Level (C.L.) upper limit to the local magnetic monopole flux was set at the level of $1.4\times 10^{-16}$ cm$^{-2}$ s$^{-1}$ sr$^{-1}$. This result is the first experimental limit obtained in direct searches which is well below the Parker bound in the whole $β$ range in which GUT magnetic monopoles are expected.

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The MACRO Collaboration. 2002-07-09. Final results of magnetic monopole searches with the MACRO experiment. https://doi.org/10.1140/epjc%2Fs2002-01046-9

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