TOP ISOTOPES OF CALIFORNIUM
Californium Isotopes – list and properties
Below you can find information on how many Californium isotopes exist, as well as whether they are stable or not, their properties and their uses in various industries.
List of isotopes
Currently, the science community has listed twenty known isotopes of the element in mind, along with one nuclear isomer. The first isotope of the radioactive source starts at 237 as its atom number and goes all the way to 256 of the same. The most usable Californium isotopes are 249, 250, 251 and 252. The isotopes with the greatest longevity are 251, 249, 250 and 252 in that order. They have a half-life of 898, 351, 13.08 and 2.645 years respectively. The remaining isotopes have shorter half-lives, either shorter than one full year or shorter than 20 minutes.
Production
The 249 “derives” from Berkelium-249, undergoing through beta decay along the process. The same is true (production wise) for 250, but instead of only beta decay, the 250 is a product of neutron capture also. Neutron capture is a process through which a neutron collides with an atomic nucleus, because of that making the heavier atomic nucleus. This process is widely known as a nuclear reaction.
But, it turns out Californium-251 has the longest half-life span, despite its short percentage of production output (only 10%). It also characterizes with small critical mass, and it’s lethal. Due to the small critical mass that possesses, some were lead to believe one can practically use the isotope in various industries (an exaggerated claim). The 251 is made from bombarding the 250 with neutrons, as described above.
Finally, the most potent isotope is Californium-252. The radioactive source is also made from bombarding Californium-250 with neutrons, just as its predecessor, the 251. Also, this is not the only process by which scientists produce it. Americium, Plutonium, and Curium, while subjected to prolonged irradiation, all make small quantities of 252. Irradiation is when a substance becomes radiated.
History
The first gathering conference about the 252 was made possible by the ANS (American Nuclear Society) in 1968. Afterward, conferences happened in 1972 in Washington D.C, discussing the element for possible medical, industrial and oceanographic studies and implementation. Today, it’s produced in the form of transplutonium isotopes for special research purposes.
Application
Of all mentioned, only 252 has its way with practical uses. It can be used to find corrosion via neutron radiography in aircraft carriers, metal detectors or different weapon types. It’s also applicable to healthcare, nuclear reactors or elements detection, to name a few. Perhaps the most interesting practical usage lies in the gold and silver ore discovery, through a process known as neutron activation.
Properties
A microgram of the neutron emitting source has the power to produce one hundred and seventy million neutrons per one minute. It usually comes in pellet or palladium wire form. Its outside diameter can go as far as 9.423 millimeters while the inner one reaches 5.982 millimeters. It has a standard tolerance of +/- 10 percent and typically undergoes pressurized helium leak with Alpha, Beta and Gamma tests.
Multi-elemental analysis
Californium-252 had an interesting application when it was first discovered. Namely, it was used to help in moon rock study for NASA, at the University of Kentucky. The facility provided fertile grounds for both liquid and solid samples, and as such it was used in sediment, alloy, and rock solution research.
Educational application
It started in 1969 when Georgia Tech received 119 micrograms of the substance from Savannah River Plant. Since then, the neutron emitter found its way in several research centers: Francis Marion University, Oak Ridge Associated Universities and others. According to Irvin W. Osborne-Lee and C. W. Alexander, as much as 78 facilities were using it on loan, in a total of 7 milligrams per facility.