Physicist <a href="https://en.wikipedia.org/wiki/Harry_Daghlian" id="mw-Q" rel="mw:WikiLink" title="Harry Daghlian">Harry Daghlian</a> is fatally irradiated in a <a href="https://en.wikipedia.org/wiki/Criticality_accident" id="mw-g" rel="mw:WikiLink" title="Criticality accident">criticality accident</a> during an experiment with the <a href="https://en.wikipedia.org/wiki/Demon_core" id="mw-w" rel="mw:WikiLink" title="Demon core">Demon core</a> at <a href="https://en.wikipedia.org/wiki/Los_Alamos_National_Laboratory" id="mw_A" rel="mw:WikiLink" title="Los Alamos National Laboratory">Los Alamos National Laboratory</a>.