CHAPTER TWELVE EINSTEINIUM Richard
نویسنده
چکیده
The discovery of einsteinium, element 99, came about during the analyses of nuclear products produced in and then recovered from test debris following a thermonuclear explosion (weapon test device, ‘Mike’, November 1952) at Eniwetok Atoll in the Pacific Ocean. The uranium present in this device was subjected to a very intense neutron flux (integrated fluence of about 10 neutrons) in an extremely short time frame (few nanoseconds), which allowed a large number of multiple neutron captures with a minimal degree of decay of the products formed. Nuclei were formed with usually high neutron/proton ratios (very ‘heavy’ uranium isotopes), which then rapidly beta‐decayed into new, transuranium isotopes through element 100. Scientists from several U.S. Government laboratories separated and analyzed extensively the debris samplings in the following weeks. From these investigations came the discovery and identification of einsteinium and fermium. The first element was named in honor of Albert Einstein, and assigned the symbol, E (later changed to the current symbol, Es). Additional details and discussions about the discovery of this element and the scientists involved are given in several references (Thompson et al., 1954; Ghiorso et al., 1955; Fields et al., 1956; Hyde et al., 1964; Seaborg and Loveland, 1990). Subsequently, einsteinium has been produced in accelerator targets, and in reactors via successive neutron captures, starting with targets of plutonium or higher actinides. The first macroscopic and weighable quantities of einsteinium 12.
منابع مشابه
Einsteinium declassified.
On the first of November 1952, in a top secret test known as Mike, the United States detonated the ‘Sausage’ — the world’s first hydrogen bomb. The explosion annihilated the entire Pacific island of Elugelab, but it wasn’t all devastation; at the same time it created two new elements that their discoverers would later name einsteinium and fermium. The explosion was colossal, being more powerful...
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