Leptonic ALP portal to the dark sector

Summary

We discuss the leptonic axionlike particle (ALP) portal as a simple scenario that connects observed discrepancies in anomalous magnetic moments to the dark matter relic abundance. In this framework an axionlike particle in the multi-MeV range couples to SM leptons and a dark matter (DM) fermion, with mass above the ALP mass but below 1 GeV. The ALP contributes to <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mo stretchy="false">(</a:mo><a:mi>g</a:mi><a:mo>−</a:mo><a:mn>2</a:mn><a:msub><a:mo stretchy="false">)</a:mo><a:mi>μ</a:mi></a:msub></a:math> and <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:mo stretchy="false">(</e:mo><e:mi>g</e:mi><e:mo>−</e:mo><e:mn>2</e:mn><e:msub><e:mo stretchy="false">)</e:mo><e:mi>e</e:mi></e:msub></e:math>