Via Swans on Tea, a new article on the arxiv reports the possible discovery of a new stable element:
What they did was fire one thorium nucleus after another through a mass spectrometer to see how heavy each was. Thorium has an atomic number of 90 and occurs mainly in two isotopes with atomic weights of 230 and 232. All these showed up in the measurements along with a various molecular oxides and hydrides that form for technical reasons.
But something else showed up too. An element with a weight of 292 and an atomic number of around 122. That’s an extraordinary claim and quite rightly the team has been diligent in attempting to exclude alternative explanations such as th epresence of exotic molecules formed from impurities in the thorium sample or from the hydrocarbon in oil used in the vacuum pumping equipment). But these have all been ruled out, say Marinov and his buddies.
You know, I see a lot of science stories that sound like kookery, but this is the first in a while that sounds like Golden Age SF. I mean, really, discovering an entirely new element by mass spectroscopy? Isn’t that the start of a “Doc” Smith story?
If only if we could carve a proper cam, we could check your hypothesis!
There is easy way to test the methodology:
1) repeat the result on another instrument
2) do chemical a fractionation on the sample, such as precipitation and see if there is enrichment and depletion.
Its not like we are chasing isotopic ratios here; if its a new element, this heavy thorium analog has to have a rather different properties and a change in abundance would be rather easy to bring about.
personally I give it only 1 in 50 chances that it is a real thing, and not some artifact
The experiment seems conceptually rather straightforward, and I wonder whether someone else has already done something like this. I’d bet that there are several laboratories that are gearing up for it right now.
I just looked up Unbibium in Wikipedia, and they do make mention of this report. There is also a pointer to a skeptical report:
http://www.chemistry-blog.com/2008/04/29/adressing-marinovs-element-122-claim/
Gosh! Have they tried exposing it to a current while in contact with copper?
I’d keep an eye out for labmates with narrow beards and shifty eyes, regardless.
http://arxiv.org/abs/0804.3869
Beautiful work. “An element with a weight of 292 and an atomic number of around 122.”
Z = 118 is the synthetic superheavy record. A heavy ion particle accelerator can be used as a high precision mass spec and as a calutron.
This could be fun – especially if the nucleus is long-lived because it has a spin of 30(h-bar). Artifact or hot momma discovery? Fire up those Manhattan Project calutrons!
The ratio of 292/122 is also about what one expect for an element with atomic number of around 120. This makes the claim slightly more plausible. But I’m having trouble understanding how something like that could be reasonably stable without serious upsetting our understanding of physics.
But I’m having trouble understanding how something like that could be reasonably stable without serious upsetting our understanding of physics.
Background here:
http://en.wikipedia.org/wiki/Island_of_stability
I am composing a blog at the same time I am writing this comment. Suffice it to say that the name “R. V. Gentry” in the author list brought back fond memories of a previous discovery of a superheavy nucleus (with Z=126) back in 1976. This proved to be totally bogus, but it was great fun to see the excitement of the meeting when everyone was trying to figure out what was going on. [What was going on was a weak, previously unknown x-ray line, where Z=126 should be. Gentry had botched the background check.]
The biggest problem with this claim is that the mass is too low. Way too low. [118]294 is barely seen with a short half life. Adding 4 protons and removing 6 neutrons to get [122]292 moves you away from the valley of stability, not toward it.
By the way, there is nothing simple about mass spec when you want to see a single atom out of bazillions and have all kinds of gunk that can form molecules with crazy Z/A combinations. That is the point of the critique by the nuclear chemist cited above.
Oh, did I mention that Gentry is a Young Earth Creationist? That ought to raise your blog hit rate ….
IGYDaze, I’m familiar with the notion but as I understand the predicted increase in stability at that point shouldn’t be enough to have a half-life that allows it to stick around in nature for indefinite periods. The only plausible mechanism for this element to have been created would have been supernova so we’re talking about a half-life in the range of at least hundreds of millions of years. This is probably the part where I should loudly claim that I’m not a physicist. Now from what I understand even as we have islands of stability the overall trend of stability is pretty steeply downwards. I would not have guessed that it would have a half-life near the relevant range.
Joshua, Gentry would be ecstatic if it turned out to have a half-life of a thousand years. See above.
He is not deterred by evidence that the U-235 concentration was high enough in the (necessarily distant) past to have a natural fission reaction take place at Oklo.