The MoEDAL and the Nature

Limits on the mass of magnetic monopoles could be established for the first time, as the production cross section for the Schwinger mechanism is calculable nonperturbatively. Several models beyond the Standard Model of Physics predict monopoles with low-enough masses to be detectable at the LHC, and in most of these models the monopoles have composite structure, as opposite to the point-like object of Dirac-like monopoles. But production of composite monopoles is expected to be exponentially suppressed in elementary particle collisions conducted previously. The Schwinger mechanism of production in heavy-ion collisions is not subject to this suppression, so this is the first search at the LHC where composite monopoles could be realistically produced. LHC collisions of Pb ions produced the strongest magnetic fields in the known universe, stronger than in magnetars, so our limits are stronger than the ones inferred from astrophysical and other sources.

Vasiliki Mitsou, researcher at the Institute of Corpuscular Physics and leader of the MoEDAL group in Valencia, is also the analysis coordinator of this experiment. She has led all the steps to obtain these new results and has been one of the internal reviewers of the collaboration article.

«The synergy between experimental and theoretical physicists at MoEDAL has allowed, for the first time, the search for monopoles of finite size, inaugurating also the use of the powerful magnetic field present in the collisions of heavy ions at the LHC. This Schwinger mechanism allows us to calculate physically valid monopole production probabilities» says Vasiliki Mitsou.

Published in Nature Nature, 602, 63-67