Skip to comments.Mercury serves up a nuclear surprise - The discovery of a new type of fission turns a...
Posted on 12/04/2010 10:40:33 AM PST by neverdem
The discovery of a new type of fission turns a tenet of nuclear theory on its head.
The observation of an unexpected nuclear reaction by an unstable isotope of the element mercury has thrown up a rare puzzle. The enigma is helping theorists to tackle one of the trickiest problems in physics: developing a more complete model of the atomic nucleus.
Nuclear fission, the process in which a nucleus heavier than that of iron breaks into pieces, is generally observed to be symmetric, with the resulting fragments being roughly equal in size. Although instances of asymmetric fission are known, they are usually attributed to the preferential formation of 'magic' nuclei, in which shells in the nuclear structure are filled to capacity.
So when researchers on the ISOLDE experiment at CERN, Europe's particle-physics laboratory in Geneva, Switzerland, set out to study the decay of mercury-180 containing 80 protons and 100 neutrons they expected it to break into two nuclei of zirconium-90, each containing 40 protons and 50 neutrons. They assumed that outcome would be particularly favoured because 40 and 50 are magic numbers for which shells would be exactly filled.
But the mercury dealt a surprise, splitting instead into ruthenium-100 and krypton-80. "A symmetric split should be dominant and we show that it doesn't happen," says ISOLDE member Andrei Andreyev, presently of the University of the West of Scotland in Paisley. The result is in press at Physical Review Letters.
ISOLDE is unique in being able to create pure beams of unstable heavy elements, the reaction products of which can be collected and studied. Andreyev and his colleagues started with a beam of thallium-180. This mostly decayed by capturing an electron, turning one of its 81 protons into a neutron to form mercury-180, which then performed the...
(Excerpt) Read more at nature.com ...
New? I'm betting it's been around for billions of years.
So...our new mandated light bulbs will be blowing up on us?
Read for later. Thanks.
Well no wonder! This ain't real mercury. It's that cheap Swiss stuff, just a little better quality than the made in China brand.
It is new to us.
Alpha decay is highly asymmetric, but isn’t called fission. Even though it’s a nucleus splitting into two.
I think fishing not fission goin’ on he’ah.
They should try the experiment without observing it and see what happens.
What is the significance of this?
Correct. Observation is never passive. It always affects outcome. Quantifying observation can only be done by comparison with nonobservation. In a nonobservation environment the outcome cannot be known since it is unobserved. More than a theoretical problem the observer determines the reaction.
As is everything.
Whatever will be
has already been done.
and there is nothing new
under the sun.
Airport Repairman carries CFL light bulb thru TSA scanner, blows himself up
What we really need to know is if the mercury will still turn ibises gay.
As my friend Milo Price said, “Sometime things just don’t happen the way you think they will”.
Profound, truly profound.