Physics Division Seminars bring us speakers on a variety of physics related subjects. Usually these are held in the Building 6008 large Conference Room, at 3:00 pm on the chosen day, but times and locations may vary. For more information, contact our seminar chairman,
Tel (Office): (865) 574-6124 (FAX): (865) 574-1268
Within the last decade, the amount of available 3He has become limited, while the demand has significantly increased, especially for science and national security applications. The largest demand for 3He is in gas proportional counters for neutron detection. No other currently available detection technology offers the stability, sensitivity, and gamma/neutron discrimination of 3He neutron tubes. Such neutron detectors are used in many applications including neutron scattering research, international and homeland security, defense applications, and well logging. The limited supply has curtailed use of 3He; therefore, alternative neutron detection technologies must be implemented.
The production of 3He from tritium decay has declined as the nuclear weapons stockpile has been reduced, resulting in a lowered need for tritium to maintain the stockpile. The worldwide, steady state production of 3He is about 10-20 kliter/y, while the demand is much higher. This has driven the search for alternate neutron detection technologies to replace the use of 3He.
One of the two large uses for 3He has been in radiation portal monitors deployed for homeland security both domestically and internationally. This use is no longer permitted by U.S. government policy. Thus, an alternative had to be found and deployed over a short period of time. The nuclear physics community successfully met this challenge. This talk will provide an overview of the 3He supply problem and the application of neutron detectors to national security.
Alfredo Galindo-Uribarri 574-6124