Super heavy dark matter origin of the PeV neutrino event: KM3-230213A

The recent observation of the ultrahigh-energy neutrino event KM3-230213A by the KM3NeT experiment offers a compelling avenue to explore physics beyond the Standard Model (SM). In this paper, we explore a simplest possibility that this event originates from the decay of a super-heavy dark matter (SHDM). We consider a minimal scenario where the SHDM decays to neutrino and SM Higgs. We derive constraints on the DM lifetime as a function of DM mass, ensuring consistency with IceCube, Auger upper limits, and the observed KM3-230213A event, along with the gamma-ray constraints. We find that KM3-230213A gives stringent constraint on the DM mass ranging from <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mn>1.5</a:mn><a:mo>×</a:mo><a:msup><a:mrow><a:mn>10</a:mn></a:mrow><a:mrow><a:mn>8</a:mn></a:mrow></a:msup><a:mtext> </a:mtext><a:mtext> </a:mtext><a:mi>GeV</a:mi></a:mrow></a:math> to <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mn>5.2</c:mn><c:mo>×</c:mo><c:msup><c:mn>10</c:mn><c:mn>9</c:mn></c:msup><c:mtext> </c:mtext><c:mtext> </c:mtext><c:mi>GeV</c:mi></c:math> with lifetime in the range: <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:mn>1.42</e:mn><e:mo>×</e:mo><e:msup><e:mn>10</e:mn><e:mn>30</e:mn></e:msup><e:mtext> </e:mtext><e:mtext> </e:mtext><e:mi mathvariant="normal">s</e:mi></e:math> to <h:math xmlns:h="http://www.w3.org/1998/Math/MathML" display="inline"><h:mn>5.4</h:mn><h:mo>×</h:mo><h:msup><h:mn>10</h:mn><h:mn>29</h:mn></h:msup><h:mtext> </h:mtext><h:mtext> </h:mtext><h:mi mathvariant="normal">s</h:mi></h:math>. Remarkably, in our SHDM scenario, the apparent tension between the KM3NeT observation and the nonobservation of this event by IceCube and Auger can be reduced to below <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"><k:mn>1.2</k:mn><k:mi>σ</k:mi></k:math>. Our results are applicable to any neutrinophilic SHDM models while evading gamma-ray constraints.