http://arxiv.org/abs/1908.09409
The present work studies the axion quark nuggets introduced in \cite{zhitnitsky} and exploited in the works \cite{zhitnitsky2}-\cite{zhitnitsky13}, but taking into account the possibility that they become ferromagnetic. This issue was raised in \cite{tatsumi}, although ferromagnetism may also take place due some anomaly terms found in \cite{son}-\cite{son2}. The purpose of the present letter however, is not to give evidence in favor or against these statements. Instead, it is focused in some direct consequences of this ferromagnetic behavior, if it exists. The first is that the magnetic field of these lumps induces an electric field on the nugget due to the axion wall, which may induce pair production due to the Schwinger effect. A critical value for such magnetic field at the surface of the nugget is obtained, and it is argued that the value of the magnetic field of \cite{tatsumi} is at the verge of stability but otherwise pass the test. In addition, the interaction of such magnetic and electric nugget with the troposphere of the earth is also analyzed. It is suggested that the cross section with the troposphere is enhanced in comparison with a non magnetic nugget but still, it does not violate the dark matter collision bounds. Consequently, these nuggets may be detected by impacts on water or by holes in the mountain craters \cite{nature}.
O. Santillan and M. Sempe
Tue, 27 Aug 19
67/85
Comments: 15 pages. No figures