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Gamma-Ray Measurements of a 6-Kilogram Neptunium Sphere

Conference ·
OSTI ID:976203
 [1];  [1]
  1. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
In order to better determine the properties of 237Np for criticality safety and nuclear nonproliferation, especially its critical mass, 6070-gram solid sphere was cast on 15 May 2001 in a hot cell. The casting sprue was cut off on a lathe and the casting ground to a final diameter of 8.29 cm. The sphere was enclosed in a spherical tungsten shell 0.523-cm thick to reduce the gamma-ray dose. The neptunium and the tungsten were doubly encapsulated in welded, spherical nickel shells, each 0.381-cm thick. The sprue material was analyzed by mass spectrometry. Here we report the results of the first gamma-ray measurements of this unique item.
Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP)
OSTI ID:
976203
Report Number(s):
LA-UR--02-3601
Country of Publication:
United States
Language:
English