Particle Accelerator Reveals A New Type of Atomic Nucleus

Finland's University of Jyväskylä has an announcement: an experiment performed in its accelerator lab "has succeeded in producing a previously unknown atomic nucleus."

Dubbed "190-Astatine," it's made from 85 protons and 105 neutrons.. The nucleus is the lightest isotope of astatine discovered to date. Astatine is a fast-decaying, and therefore rare element. It has been estimated that in the Earth's crust, there is no more than one tablespoon of astatine...

The new isotope was produced in the fusion of 84Sr beam particles and silver target atoms. The isotope was detected among the products by using the detectors of RITU recoil separator... "The studies of new nuclei are important for understanding the structure of atomic nuclei and the limits of known matter," says Doctoral Researcher Henna Kokkonen from the Department of Physics, University of Jyväskylä.

Big deal

[backslashdot]

Call me when they build a nucleus using only neutrons and no protons.

Re:

[Sique]

Oh, they can built nuclei using only neutrons and no protons. Alas, as soon as the nuclei form, some of the neutrons beta-decay into protons.

(And of course, there are neutron stars, which essential are nuclei the size of New York and with more mass than the whole Solar system.)

Big Nuclei

[Roger W Moore]

Oh, they can built nuclei using only neutrons and no protons. Alas, as soon as the nuclei form, some of the neutrons beta-decay into protons.

You can build stable ones as long as you go big, neutron star big. However, I think it is a bit dubious to call smaller pure neutron states "a nucleus" since they are not bound states, just resonances.

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[Sique]

That's what I said: Some of the neutrons will immediately (within 10 to the power of -23 seconds) beta-decay into protons.

Re:

[test321]

Japanese accelerator RIKEN observed the 4-neuron nucleus in 2022 https://www.nature.com/article... [nature.com] see also wikipedia https://en.wikipedia.org/wiki/... [wikipedia.org]

Re:

[Roger W Moore]

Not really, it observed a 4-neutron resonance. It's not really a nucleus unless it is a bound state and you'll note that the paper does not use the term "nucleus" and refers to it as "quasi-bound". It's definitely an interesting result though.

Re:

[RockDoctor]

Before I RTFA, I'd estimate the half life of that at a bit under 3 minutes.

I RTFA.

Lifetimes cited of 10^(-21 ~ -22) s. Which is about 3 minutes under 3 minutes. Oh well, I'm not a nuclear physicist - I just use nuclear tools for paying work.

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[McLoud]

Call me when they build a nucleus that's stable and not found in nature (eg: no fast decay)

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[Tablizer]

They already did, but nobody can see nor detect it. It's called the "notron".

Unfinnished physics

[dsgrntlxmply]

The decay products are umlauts and doubled letters. Also, I checked all of my tablespoons, and none were even slightly warm or could br located without a flashlight.

Summary does not do Henna justice

[SuperKendall]

From the linked article:

The discovery of 190-Astatine was made by Master of Science graduate Henna Kokkonen as part of her thesis work,

The summary mentions her name but doesn't mention she is the person who made the discovery! It made it sound like the discovery was made more by the school...

Re:

[joe_frisch]

With modern experiments, sometimes "discoverer" is not clearly defined. A lot of larger projects have gone to publishing as a "collaboration" rather than under individual names for this reason.

I don't know how big an experiment this was, but its quite possible there was: The person who thought As190 would be stable enough to detect. The person who calculated it could be created in this accelerator. The person who applied for and got funding for the experiment. The person who designed the detection app

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[Surak_Prime]

This is why whenever the subject of Thomas Edison comes up, I deny him most of his inventions in the conversation, because most of them were actually invented by employees... but then always make sure to point out that what he *did* invent, which was at least as important as the other stuff, was the concept of the modern research lab. How many advances have we made because individual efforts have been unified and individual egos have been paid off so that things could be invented by, for example, "Dow Chemi

Interesting, but what does it mean?

[HiThere]

Does this test, extend, refute, or confirm any theory that was in doubt? Or is this just "Here's another edge case.".

More of a new nucleus than a new type of nucleus

[JustLikeToSay]

If it was made of eg small bits of lint and those tiny screws that help hold watch-batteries in place I'd agree that it is a new type of nucleus.