Name: This Superheavy Atom Factory Is Pushing the Limits of the Periodic Table
Uploaded: 2020-04-13T17:24:32.000Z
Duration: 9 min 51 s
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Inside this labyrinth of pipes and chambers, superheavy elements are being fused into existence.

This machine is part of an international hunt to unlock the mysteries of this new class

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of elements that typically don't exist here on Earth.

Pushing these element discoveries really is pushing into models of how matter is formed

And how do we model the formation of the universe?

Superheavy elements exist for a fraction of time and are nearly impossible to catch.

But understanding them could force us to reimagine the most iconic scientific symbol of all time:

In 1869, Russian chemist, Dmitri Mendeleev, laid the foundations for what would become

He arranged the known elements in order of increasing atomic weight–starting with the

lightest ones with the least protons and working his way up.

And as he did so, a curious pattern started to emerge.

What happened is he noticed that at regular intervals, chemical properties were repeating

Because of this periodicity in the chemistry, he realized that there were elements at that

time that had not yet been discovered but should be there.

In the following years, scientists started isolating the elements Mendeleev predicted

Scandium was found in a hunk of euxenite, gallium in a piece of zinc ore, and hafnium

The table's design was revised and perfected as more elements were added.

But as nuclei got heavier and heavier, finding them became a bit more complicated.

When we refer to heavy elements, we're talking about things that have these very large nuclei

Above uranium, nothing exists here naturally.

They have more protons in their system than anything that we have naturally occurring.

In order to continue their quest towards a complete periodic table, scientists couldn't

just continue isolating elements from existing materials.

So we use what's called a particle accelerator or specifically a cyclotron, which is a large

instrument that accelerates ions to a fraction of the speed of light.

Cyclotrons have been used to discover heavy elements ranging from curium to plutonium.

And most recently, Dr. Shaughnessy's team collaborated with a lab in Russia to complete

the periodic table's 7th row– the home of the superheavies.

When we make one of these new elements in the cyclotron we really have to just add up

So for instance, if we wanted to look for element 116, we could take something with

20 protons and we can take something with 96 protons, and if we can get those two nuclei

to completely fuse together for even a short time that means we have an element 116, one

These elements are very short lived they're not very stable, so they decay very quickly.

Some superheavy elements only exist for just milliseconds.

So, in order to confirm they created one, the team had to work backwards– sifting

through the data to find the signal that told them a heavy element was actually there.

The Flerov lab in Dubna has an incredible cyclotron that's really a work horse.

And we at Livermore have access to various target materials.

So we provided our expertise, the Russians provided their expertise, and together discovered

While efforts to discover more elements continue, Dr. Shaughnessy and Dr. Gates have shifted

their sights to studying the ones we already have.

We know almost nothing about these superheavies, including whether or not we've put them

in the right place on the periodic table.

Right now, when an element is discovered, we're putting it in the periodic table based

But the periodic table, let's remember, it was constructed to be a living document on

The models predict that these heavy elements might behave unexpectedly due to something

We have these big massive nuclei and what's happening is they're accelerating their electrons

to near relativistic speeds.They're going so fast that they're being dominated by the

What that does is it's changing the mass of the electron and that's changing how it bonds

So when we get to this last row of the periodic table, what we see sometimes, is that the

chemical properties down a given group may invert or do something totally different.

We believe that we have them in the right position, but we also don't think we've proven

And so, what we did was we built FIONA to actually prove that what we think is true,

Hooked up to the Lawrence Berkeley National Lab's 88 inch cyclotron, FIONA is one of

the newest tools designed to study superheavy elements.

Its primary goal is to experimentally confirm their mass numbers.

But before FIONA can measure the mass, the team needs to create a superheavy element.

So we are in cave one at the Building 88 facility.

The beam comes from the cyclotron, which is right through that wall, and then it travels

all the way down this line here until it reaches our target out the other side.

This is what our targets look like, or this is three fourths of a target.

We have just a couple of thousand atoms thick of whatever our target material actually is.

What we're interested in is one nucleus from the beam hitting one nucleus from the target

The problem is that doesn't happen very often.

Nuclei are very small compared to atoms, so a nucleus is about 10,000 times smaller than

When the beam comes in, what it actually sees is mostly empty space. It actually passes through

And then very, very rarely we'll get this head-on collision that makes that atom that

Right inside this box, that's where our elements are made.

Now our job is to find a way to separate all that junk that we don't want, from that one

Everything travels through the Berkeley Gas-Filled Separator - a machine equipped with giant

magnets that bend the excess atoms away from the superheavy the team is interested in.

It traps it in a small volume, and then it sends it on to stage two of FIONA.

Magnetic fields then send the superheavy atom into a specialized loop.

And, it's the specific path it takes within that loop that tells the team its mass.