Scientists Discover First 'Neutron-Rich' Isotope of Uranium Since 1979

An anonymous reader shared this report from LiveScience: Scientists have discovered and synthesized an entirely new isotope of the highly radioactive element uranium. But it might last only 40 minutes before decaying into other elements. The new isotope, uranium-241, has 92 protons (as all uranium isotopes do) and 149 neutrons, making it the first new neutron-rich isotope of uranium discovered since 1979. While atoms of a given element always have the same number of protons, different isotopes, or versions, of those elements may hold different numbers of neutrons in their nuclei. To be considered neutron-rich, an isotope must contain more neutrons than is common to that element...

"We measured the masses of 19 different actinide isotopes with a high precision of one part per million level, including the discovery and identification of the new uranium isotope," Toshitaka Niwase, a researcher at the High-energy Accelerator Research Organization (KEK) Wako Nuclear Science Center (WNSC) in Japan, told Live Science in an email. "This is the first new discovery of a uranium isotope on the neutron-rich side in over 40 years." Niwase is the lead author of a study on the new uranium isotope, which was published March 31 in the journal Physical Review Letters...

Niwase and colleagues created the uranium-241 by firing a sample of uranium-238 at platinum-198 nuclei at Japan's RIKEN accelerator. The two isotopes then swapped neutrons and protons — a phenomenon called "multinucleon transfer." The team then measured the mass of the created isotopes by observing the time it took the resulting nuclei to travel a certain distance through a medium. The experiment also generated 18 new isotopes, all of which contained between 143 and 150 neutrons.

Dupe

[ChunderDownunder]

https://science.slashdot.org/s... [slashdot.org]

Re:

[Mousit]

It's even the very same cut and paste quote, word-for-word, from the same source.

I actually think it might literally be the same submission, just cleaned up slightly (removed the "(opens in new tab)" that was lazily left in the original paste from the first /. post, for one) and posted. Which would mean EditorDavid did some.. (*gasp*) editing! And makes it all the funnier to think he might've actually bothered to edit for once, but still couldn't be bothered to check that it'd already been posted.

If i

Re: Dupe

[PPH]

To be fair, the memories of Slashdot editors have a very short half life.

Natural uranium isn't very radioactive

[MarkRose]

highly radioactive element uranium

Most uranium is only mildly radioactive. With a half life of 4.5 billion years, Uranium-238, which makes up over 99% occurring in nature, decays very slowly.

This new isotope is highly radioactive, but most uranium is not.

Here's a bomb....

[Kelxin]

You have 40 minutes to fly to your target and drop it before it's a sandwich.

Since last week, not 1979

[q_e_t]

No text.

Re:

[dsgrntlxmply]

Unless you ate tritiated bean soup, the neutrons are safely packed in tamper resistant shells.

New?

[nospam007]

Uranium-241 is an isotope of the element uranium, which is a naturally occurring radioactive metal. It is a radioactive isotope with a half-life of approximately 14 years. Uranium-241 is produced by the decay of neptunium-237, which is itself a decay product of uranium-235.

Uranium-241 emits alpha particles as it decays, which makes it a significant contributor to the overall radioactivity of spent nuclear fuel. It is also used in the production of nuclear weapons and as a target for the production of pluton

Re:

[Mendenhall]

Do you have a citation for this? According to the IAEA chart of the nuclides: https://www-nds.iaea.org/relns... [iaea.org] very little is known about U241. That chart is a fairly definitive summary of the current state of data.

Re:

[nospam007]

"Do you have a citation for this?"

Was lazy, just asked ChatGPT and pasted the answer.
I guess it lied again?

not discovered

[groobly]

not discovered; created.

Re:

[dfm3]

No, the terms "discovered" or "synthesized" are the verbs that the industry typically uses in the literature when discussing new isotopes; I'm not sure why, but it's the de facto standard.