Yeah, it's been around for a while.

I think if it's around it all, I've read about it.

I think a couple of 2016 it was the first time I came across it.

This work done by these nuclear physicists in Hungary.

They were looking at beryllium, the nucleus of beryllium.

It's got four protons, and for neutrons in it, you can excite this nucleus.

We know with atoms and the electrons, right?

If you exciter the electrons in an atom, they raise up in energy level on, then they don't want to stay there.

We're all lazy, really right.

We want to go back to what we call our ground states, and that's how we produce light.

And so we're all familiar with the consequences of that.

But in fact, you can do with the nucleus as well.

What they do is they create an excited beryllium nucleus by They had to start with a lithium nucleus, and then they attach a proton to it, so of a very specific energy.

So here's my lithium nucleus and incomes a proton with a very specific energy.

It then forms a beryllium nucleus, which is already at an excited state.

So that and that excited state is compared to its natural ground state.

It doesn't want to stay like this, right?

It And so what?

Actually usually happens.

It's just disintegrates again.

It just goes back to the proton goes out and the elect with the lithium.

But every now and again, what actually happens is as it drops back down to its ground state is it emits a virtual photon on that virtual foot on, just goes and disappears off on you.

Then every now and again, even less likely is that is that it admits the photon on.

Then the foot on itself creates a pair of electron electron positron pair and plus you mind is pair.

Now what usually happens is in those situations the four tons coming out on DSO the two particles the electron positron pair.

They're very light particles.

So when they created their almost Colin E.

A.

With the outgoing vote on it.

So photons coming out towards you, Brady on then the electron positron pair of created and and so the angle between them, this is the crucial thing is usually rent remain small and so as the angle increases the number of electron positron pairs that come out at larger and larger angles decreases because it doesn't want to do it.

It wants to create come out because of conservation of momentum, easier for its come out straight forward.

You know what these are people noticed was that at an angle of about 140 degrees.

So let's see.

This is zero eyes out.

1940 mean is out here.

They found a bump.

They found an increase in the number off electron positron pairs coming out.

And we know from our Higgs deaths that if you've got an increase on a number of events, then some it za potential sign that something's funny going on.

You would normally have expected this number coming out as you increase angle just to drop off anatomically.

But it suddenly it went up.

What could be causing this?

One interpretation is it is a particle that's being produced that then decays itself into the e plus C minus on.

This is the ex particle on when they work out.

Given the angle that the E plus C minus pair come out 140 degrees, you can work out what the corresponding mass of the particle must be on its 17 million electron volts.

1700 e.

On.

That's where the X 17 comes from.

It's the it's the mass of this particle incomes.

The initial proton comes out in from outside, lifting its solidity and converts it into a beryllium nucleus, which has now got four protons informed by fine tuning the incoming Proton energy.

You can raise the energy level of this nuclei of the beryllium to actually sending his 18.16 MTV 1,000,000 electron volts, and that's an excited, steady.

It's not the ground step.

It then decays as it decays.

Rather than creating the photon, which then creates the electron positron pair, it creates this ex particle.

So that's when the X 17 that's when there during the during the relaxation of the excited Yeah, it creates this, but it's a massive particle, so it's coming out now with relatively low momentum.

That then means that when it went, it decays.

That's when it doesn't split it.

Does it split?

Create the electron positron pair There can come out of a large angle.

Ah, where's the photon?

Couldn't because of the high momentum's going, then I want to go directly into the policy, minus in the same direction.

So because the X 17 is so sluggish on has less momentum.

It creates this ability to do a wider angle.

I don't actually, it's split on de.

So that was the interpretation.

And they wrote this up.

It didn't do a lot for a for a while.

For a few months, it sort of lead there.

But I remember reading a paper by I'm Jonathan Fang and his collaborators of Irvine, where they were looking at this experiment and trying to interpret this results in terms of some model.

And so it was then die.

I remember reading it and thinking in order to explain this result, they're having to do something.

Some twists and turns in the particle physics beyond what you would normally expect from the standard model of particle physics.

In order to get thes thesis, Ex particle is a bows on.

It's got spin one on dhe.

There have been experiments looking for these particles.

The 48 experiment is one.

It's CERN, which had been looking for virtual bo zones like these and haven't found any on but In fact, it would naively have ruled out this experiment of the beryllium from their own results.

And in order to sort of make sure the two were compatible, Fang and collaborators realized that one way of doing it would be too effectively change some of the interactions that the protons were having with this ex particle, such that it would be access.

It would be allowed for the beryllium experiment to do what he was doing.

But it would account for the fact that the n a 48 experiment was not seeing anything.

It's generous, a lot of interest.

I mean, I think there's like 100 and 40 papers have been written citing this original work, but it was back in 2016.

I think the thing that has caused the renewed interest the same group in Hungary produced new results this time not using beryllium, but using a helium nucleus.

They did the same sort of experiments on dhe.

They found that once again, if there was a bump when they were looking at the creation of the electron positron pair, they found a bump, not a 140 degrees, which was the result for the brilliant, but I think 115 degrees on Dhe when they work, then work backwards and took into account the fact this was a helium nucleus and not a beryllium nucleus.

They once again found that the corresponding mass of the particle that if you dick understood it is from the decay of a particle was I think it's 16.7 million electron volts again comparable to what they had before.

That sounds like a smoking gun.

It does sound like a smoking gun.

It's quite intriguing.

But in the meantime, there have been the initial results that they turned in 2016 has, of course, got people thinking about this.

And the experimentalists at CERN have been.

There's an experiment called, I Think Any 64 which published its results in 2000 and 6 2018 So about a year ago, where they went looking for the original X particle, right, they went looking for a gauge bow zone, which had a massive about 16.7 million electron volts, and the way they did it was they used the Super Protons Synchrotron Collider at CERN.

They had a beam of electrons of about 100 G V.

It's a Giga electron volts.

They collided into a target, so it's called a beam dump.

They collided into a target because if this particle was there, what would happen is that electrons that we've been stopped as it hit the target could interact with actually Zed, Bozon said.

Victor Bosoms in the target on day in principle could produce this ex particle on.

Then the ex particle bean, with its interactions, could actually leave the beam dump on.

It would then decay further down the chain Andi in a set of detectors, creating the plus C minus pair.

And so what they were looking for with these two sort of almost simultaneous events not quite simultaneous, where the beam dump loses an amount of energy, but that same amount of energy is found further down the line on the interpretation would be the electron had, as it hit the Zen bow zone would have created this particle, which then moved out from the beam dump further down into the debts.

Detection decayed, and they didn't see it.

They saw no evidence of it, and so that has allowed them to rule out regions of the parameter space that the original paper was was exploring.

But this new results, which is with helium, sort of it sounds like a smoking gun.

It somewheres it is because it's a new nuclei.

But what it's really, really crying out for is another experiment along the same lines as the brilliant one, but done by a different team, right?

So what?

Why did Why did people so readily accept The Hague's?

Well, I think there were two major reasons.

One was mathematically.

It was expected to be in the ballpark where it was found.

That's why they built the L.

H.

C.

With the energy they did on the size it did.

So the mathematics of the standard model and be understanding model had suggested there should be something there on then to detectors.

Totally separate detectives found it effectively.

Simultaneously.

They were finding evidence for the Higgs.

That's the CMS detector.

Annapolis.

We're finding it simultaneously.

In this case.

There's one experiment and is found it.

Once it's there's a bit of a track record where they have found events before they disappeared.

Found evidence of these broad zones of different masses have disappeared.

They're arguing this is a stronger result.

But they found it for beryllium and now for helium that that's positive.

But what it's really requiring is another experiment along those lines to come along and say yes and confirm it.

Have other teams tried?

Or are there other teams around the world who have done similar experiment and said, We haven't found that bump but those angles?

I'm not aware of the experience doing exactly what the brilliant the Hungarian guys are doing because they're doing a proper nuclear physics experiments.

And so this is this interesting interface between nuclear physics, natural particle physics, that the experience that I'm aware of, the testing, this our particle physics experiments colliding electrons at a high energy into a being dumped on looking for different types of detectors, looking for that matter, detectors.

I mean, one of the exciting things about this result, if it was toe hold, is that there are dark matter models which would have a particle of around 10 20 million electron volts.

These light particles could be there on bees.

There are models where they're these rector bosoms.

When I talked about that, why why did we believe that Higgs.

I said, Well, because the standard model was suggesting on beyond such suggesting that it should be there.

It was in the mathematics.

One of the things that has had they've had to do in this particular case from the theoretical standpoint, is you.

We've had to do some quiet, severe twists and turns to the particle physics to make sure we can accommodate this result in terms of a particle, whilst also accepting any 48 didn't find it that certain.

It's not an easy fit.

It's not an easy fit.

And in fact you've basically had to introduced a new charge that accounts for why this ex particle doesn't interact with the proton like it would with the electron.

And in fact, it's it's called prata phobic.

It doesn't want to interact with the proton.

It will happily now interact with the neutron, but not with the proton.

And that's unusual.

Photons normally will interact with the proton, and you're forcing this to do it.

And so you need to look, for example, is why this is not happening.

Is there another logical explanation doing the rounds?

Are there other physicists who are saying, I know I can explain those bumps at those angles.

It could just be, you know, x y zed.

Well, I think the if you want it to be so one possibilities.

As I said, it was one possibility That's a mistake.

And Oh yeah, yes.

So we should should point that out, Of course.

Right that the That's another reason why you need to do this experiment with another group that there Maybe they've got their systematics wrong.

That perhaps this bump is I mean, the the words you hear is this is like a seven Sigma Detection or seven signal means it's one one chance in 100 billion that it's a random event.

I mean, that's so.

But if you've missed some big systematic that that could all go away.

I'm not aware of any sort of realistic accepted particle physics explanations as to what this is.

Other than people coming in with this idea of a particle or the possibility that it's Zach really know their att all we've just got to go and revisit the systematics of the experiment.

If we imagine the X 17 particle is legit, it Israel, what can you tell me about it?

Can you give me an Isaac?

Can you give me an idea on its like how big that is and charge it is.

And so it's like so an electron.

Which way actually tend to think of us?

Have bean almost massless right, is half on MTV, so this is 34 times the mass of the electron.

The proton is roughly 1000 MTV, but you, as usual, you've come up with a key question, which, which is that there's no particularly the particle that's important here on that.

Why is that?

The particle in in particle physics is symptomatic of the existence of something else.

It's symptomatic of the existence of a constant field.

So when we think of the photon in particle physics, the associative fields, the electromagnetic field, when we think of the ah, the Higgs particle that was discovered, why people were so excited was the existence of the Higgs field on DDE.

What the particles are excitation of those fields, very strong excitation tze The existence of a field means there's a force between there's an interaction between particles, and so what you are finding here is if this particle really exists, there's an associate ID X field exists on.