interaction cross-section of an elementary particle with magnetic charge and an elementary particle with electrical charge is equal zero. For the magnetic monopoles search one may try to use detectors of weak magnetic field instead of ordinary detectors of elementary particles, based on the interaction of moving (electrically) charged particles with detector’s electrical charges. 

## ACKNOWLEDGMENTS 

The authors would like to thank Prof. D. Singleton and Prof. B. P. Kosyakov for useful considerations of some questions, discussed in the article. 

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