Physicist <a href="https://en.wikipedia.org/wiki/Louis_Slotin" id="mwAQ0" rel="mw:WikiLink" title="Louis Slotin">Louis Slotin</a> is fatally irradiated in a <a class="mw-redirect" href="https://en.wikipedia.org/wiki/Criticality_incident" id="mwAQ4" rel="mw:WikiLink" title="Criticality incident">criticality incident</a> during an experiment with the <a href="https://en.wikipedia.org/wiki/Demon_core" id="mwAQ8" rel="mw:WikiLink" title="Demon core">demon core</a> at <a href="https://en.wikipedia.org/wiki/Los_Alamos_National_Laboratory" id="mwARA" rel="mw:WikiLink" title="Los Alamos National Laboratory">Los Alamos National Laboratory</a>.