Chicago pile number 1

The uranium reactor was built on a squash court of the university (and it was here that the guards donned discarded raccoon coats to protect themselves from the cold). Dubbed CP-1 (Chicago pile number 1), it was called an atomic pile because it was just that The reactor consisted of a pile of containers of uranium oxide interspersed with graphite bricks. There was a neutron source at the bottom to initiate the reaction, and neutron-absorbing cadmium rods could be inserted for control. Fermi s group demonstrated the feasibility of a uranium chain reaction by the end of 1942. 

Woods was finishing her thesis work during the summer but sometimes helped Anderson scour Chicago for lumber. CP-1—Chicago Pile Number One—Fermi planned to build in the form of a sphere, the most efficient shape to maximize k. Since the pile s layers of graphite bricks would enlarge concentrically up to its equator, they would need external... 

Chicago Pile Number One, the first man-made nuclear reactor, under construction at the University of Chicago, November 1942. Lower layer holds uranium oxide pseudospheres, unfinished dead layer overlying. Note hammer in foreground for scale. 

The experiment headed by Fermi attempted to stage the first controlled chain reaction. To produce the reaction, the Manhattan Project took over an indoor squash court located under the Sta Field stands, where the scientists constructed what they called Chicago Pile Number One (CP-1). CP-1 consisted of some 46 tons (42 metric tons) of... 

Experiments were conducted during the Metallurgical Project, centered at the University of Chicago, and led by Enrico Fermi. Subcritical assembhes of uranium and graphite were built to learn about neutron multiphcation. In these exponential piles the neutron number density decreased exponentially from a neutron source along the length of a column of materials. There was excellent agreement between theory and experiment. 

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