Harry K. Daghlian, Jr., (1921-September 15, 1945), was a scientist who died from performing a critical mass experiment at the remote Omega Site laboratory at the Manhattan Project Los Alamos laboratory in New Mexico, on August 21, 1945. Daghlian was irradiated as a result of a criticality accident which occurred when he accidentally dropped a tungsten carbide brick onto a plutonium bomb core. The tungsten bricks were being used as neutron reflectors, which serve to reduce the mass required for plutonium to be critical, and the accidental addition of this brick caused the reaction to go supercritical. 1921 was a common year starting on Saturday (see link for calendar). ... September 15 is the 258th day of the year (259th in leap years). ... 1945 was a common year starting on Monday (link will take you to calendar). ... Cyclists gather at Union Square, New York City on Julys Critical Mass Critical Mass is an event held typically on the last Friday of every month in cities around the world, where bicyclists and self-propelled people take to the streets en masse. ... Control panels and operators for calutrons at the National Security Complex. ... Los Alamos National Laboratory, aerial view from 1995. ... State nickname: Land of Enchantment Other U.S. States Capital Santa Fe Largest city Albuquerque Governor Bill Richardson Official languages English and Spanish Area 315,194 km² (5th)  - Land 314,590 km²  - Water 607 km² (0. ... August 21 is the 233rd day of the year (234th in leap years) in the Gregorian Calendar. ... 1945 was a common year starting on Monday (link will take you to calendar). ... A criticality accident (also sometimes referred to as an excursion or power excursion) occurs when a nuclear chain reaction is accidentally allowed to occur in fissile material, such as enriched uranium or plutonium. ... Tungsten carbide, WC or W2C, is an alloy of tungsten and carbon similar to titanium carbide. ... General Name, Symbol, Number Plutonium, Pu, 94 Chemical series Actinides Period, Block 7, f Density, Hardness 19816 kg/m3, no data Appearance silvery white metal Atomic properties Atomic weight 244. ... Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ... This article is about nuclear technology. ...

Daghlian died less than a month later from acute radiation sickness. Radiation poisoning, also called radiation sickness, is a form of damage to organic tissue due to excessive exposure to ionizing radiation. ...

On May 20, 2000, Daghlian was memorialized by the city of New London, Connecticut. May 20 is the 140th day of the year in the Gregorian Calendar (141st in leap years). ... 2000 is a leap year starting on Saturday of the Gregorian calendar. ... View of New London from across the Thames River New London, Connecticut is a city in New London County, at the mouth of the Thames River and on the northeastern shore of Long Island Sound. ... State nickname: The Constitution State Other U.S. States Capital Hartford Largest city Bridgeport Governor M. Jodi Rell Official languages English Area 14,371 km² (48th)  - Land 12,559 km²  - Water 1,809 km² (12. ...

See also

• List of nuclear accidents
• Louis Slotin

Pathways from airborne radioactive contamination to man This is a list of notable accidents involving nuclear material. ... A sketch used by doctors to determine the amount of radiation to which each person in the room had been exposed during the excursion. ...

External link

http://members.tripod.com/~Arnold_Dion/Daghlian/memorial.html