Physicists thought the atomic giant Flerovium was ‘magical’, but it was just a mirage


Protons don’t like being together for long. But if you have the correct number carefully balanced between enough neutrons, they may build an atom that won’t fall apart in the blink of an eye.

Theorists had suggested that 114 could be one of those “magic” proton numbers, but a recent experiment conducted at the GSI Helmholtz Center for Heavy Ion Research in Germany now makes that incredibly unlikely.

In 1998, Russian experimenters finally managed to build an element with 114 protons in its nucleus. It was later named flerovium after its birthplace, the Flerov Nuclear Reactions Laboratory of the Joint Institute for Nuclear Research.

Creating mammoth-sized atoms is not easy, it is achieved just by starting with heavy elements like plutonium and throwing them in with slightly smaller ones like calcium, until something sticks.

By “sticks,” we mean “pauses long enough to technically go through an atom,” which for mountain-sized nuclei is rarely more than a fraction of a second. For example, at 112 protons in size, the transuranic element in copernicium has little chance of lasting more than 280 microseconds.

The atomic nucleons cling to each other as an effect of the strong force shared between the trios of subatomic quarks that compose them.

At the same time, the repulsive nature of the positive charges on the protons sets them apart, meaning the entire structure teeters on the brink of collapse, should they get too close. This is why we see some nucleon or isotope combinations more often than others.

Once an atom reaches a certain size, a number of other factors related to energy and mass also play a role, making it increasingly difficult for the atom to hold together, not to mention harder for physicists to predict. her CARACTERISTICS.

However, physicists are confident that there are islands of stability in the upper reaches of the periodic table, where the arrangements of protons can form patterns and shapes that allow them to sustain life a little longer than neighboring elements.

Nihonium, or element 113, has an isotope with a half-life of around 20 seconds, for example.

However, when the flerovium signs were first leaked from a plutonium and calcium residue more than 20 years ago, it seemed like a true gatekeeper. The signature in the data suggested that the atoms were stable for up to 30 seconds before spitting out an alpha particle and briefly crumbling into copernicium.

The emotion was short-lived. In 2009, Berkeley scientists managed to recreate two different isotopes of the element. One lasted a tenth of a second. The second stayed a bit longer, crumbling after half a second.

Odds didn’t seem good for element 114, but physicists aren’t the type to leave well enough alone. So the University of Mainz went big, using improved detectors to study dozens of possible flerovium decay events.

In the end, two were confirmed as true isotopes. One resulted in an isotope of copernicium that was seen to decompose in a way that had not been previously observed.

In that case, the decay chain of the flerovium occurred in 2.4 seconds, in a detachment of alpha particles. The second isotope disappeared in 52.6 milliseconds. Importantly, the efficient way each of the two isotopes decayed made it clear that 114 was not stable in the least.

As exciting as a stable flerovium might have been, the new findings of an excited state of copernicium provide a solid foundation for exploring islands of stability higher up in the periodic table, providing theorists with vital information to further model this phenomenon.

“The existence of the state provides another anchor point for nuclear theory, because it appears to require an understanding of both the coexistence of forms and the transitions of forms for the heavier elements,” the researchers note in their report.

While we can now rule out 114 as one of the magic numbers on the periodic table, there are more giants to kill.

Physicists have yet to create the hypothetical element tentatively called unbinilium, or element 120. Crafting one of these monsters would require powerful technology and advanced knowledge of nuclear physics.

Plans are underway to push the limits of atomic masses, with RIKEN in Japan making steady progress at its Nishina Center for Accelerator-Based Science, so we may not have long to wait.

Like explorers of yore, researchers are still confident that there are stable islands just on the horizon. We will surely see some mirages along the way.

This research was published in Physical Review Letters.

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