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This Afterpop is brought to you 
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Welcome to the afterpop. 
In our previous episode, we got 

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to talk with Ryan Serpa, A 
Division One Purdue University 

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swimmer and nuclear engineer. 
Over the summer, Ryan did an 

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internship at Sandia National 
Laboratories. 

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So now we're going to go into 
something that he spoke of 

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within that episode, the Z 
machine. 

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Imagine a machine for a few 
billions of a second unleashes 

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more power than all of the 
electric grids on Earth 

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combined. 
That's the Z machine at Sandia, 

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built not to power cities but to
recreate the immense heat, 

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pressure and X-ray intensity of 
stellar interiors, planetary 

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cores, and nuclear detonations. 
In those fleeting moments, 

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scientists can test materials, 
probe fusion technologies, and 

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validate computer models for 
nuclear security. 

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So what is the Z machine, why 
was it built, and what's it for?

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There are three intertwined 
motivations. 

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First, national security and the
nuclear stockpile stewardship. 

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As nuclear weapons age, we want 
to know how materials behave 

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under extreme conditions. 
Temperature, pressure, shock, 

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those types of things. 
The Z machine let's scientists 

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simulate those conditions in a 
controlled lab setting. 

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Next, high energy density 
physics and basic science. 

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It's a tool for exploring matter
under extreme states, like I 

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said, in stars, giant planets, 
or astrophysical explosions. 

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Pretty cool. 
And lastly, fusion as well as 

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future energy research because 
it can compress heat and can 

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find plasmas at extreme rates. 
It's used in experimental fusion

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approaches, notably magnetized 
linear inertial fusion, to try 

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and hit conditions where fusion 
yields more energy than input. 

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In short, it's an extreme 
environment created to push the 

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boundaries across defense, 
material science, and fusion. 

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Now we're going to go into kind 
of how it works, sort of. 

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Imagine you have a tiny balloon 
of gas. 

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If you press it slowly, the gas 
leaks and the heat dissipates. 

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But if you slam your hands 
together fast, the gas 

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compresses, heats and reaches 
extreme conditions before it can

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escape. 
The Z machine is like that, but 

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hyper accelerated and 
electrified. 

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Now we'll move into the steps of
how it works. 

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First, it stores energy. 
The Z machine charges up a Bank 

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of capacitors over 2 minutes, 
storing around 10 mega joules. 

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But what does that mean? 
10 mega joules is about 2.4kg or

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5 lbs of TNT. 
Next discharge in a flash, AKA 

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pulsed power. 
When everything is ready, the 

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stored energy is dumped into a 
few 10s to hundreds of 

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nanoseconds. 
That's billionths of a second. 

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That concentrates the energy in 
time, producing gigantic 

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instantaneous power on the order
of 80 terawatts. 

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But what's 80 terawatts? 
80 terawatts is 80 trillion 

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watts. 
For context, the entire planet's

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electrical grids produce around 
25 terawatts at any given 

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moment. 
That means for a few billionth 

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of a second the Z machines pulse
power outshines all human 

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electricity production combined.
That's insane. 3Z pinch 

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implosion, magnetic compression.
The high current flows through a

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load, often a fine wire array, a
metal cylinder, or another 

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structure. 
The current generates a 

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magnetic. 
Field which? 

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Exerts an inward pinching force 
on the plasma. 

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This implodes the material 
inward, compressing and heating 

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it drastically. 
This is the Z pinch concept. 

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Current is moving along the Z 
axis to produce a radial pinch. 

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Z pinch 4X ray burst. 
An extreme environment. 

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As the implosion peaks, enormous
densities, temperatures, 

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pressures, and X-ray fluxes are 
achieved. 

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The target may emit a burst of 
X-rays, and researchers measure 

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how materials behave under those
stresses. 5 Diagnostics and data

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in that few nanosecond moment, A
battery of diagnostics. 

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X-ray detectors. 
Spectrometers, particle 

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detectors, captures, signatures,
everything from temperature, 

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density, radiation, and shocks. 
That data helps validate 

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computational models and test 
hypothesis about fusion and 

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material behavior. 
Reset and repeat after a shot, 

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components are refurbished. 
Reset and the cycle repeats. 

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The Z machine typically fires 
200 shots per year. 

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I think of it this way. 
You know, in those superhero 

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movies, when the hero is about 
to take off her flight, they 

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slowly bend down, building up 
all of this potential energy. 

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And then in an instant they take
off. 

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A Sonic boom is heard, dust is 
flying all around, and usually 

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some kid with that ice cream 
cone is looking at Superman 

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flying in the air. 
But with the Z machine, there is

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a sensory impact. 
You could actually feel it 

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during a firing. 
Sandia engineers report that 

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shock waves from the 
electromagnetic pulse and rapid 

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air displacement can be felt and
heard miles away. 

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The entire facility rumbles like
a small earthquake. 

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Some workers describe the effect
as a low frequency boom. 

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Not dangerous, but unmistakable.
So what are some of the 

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challenges and caveats with 
doing this type of research? 

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First, instabilities and mixing.
Plasmas are famously unstable. 

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Just check out the Rayleigh 
Taylor instability, plasma 

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turbulence, things like that. 
Maintaining symmetry and 

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preventing mixing is a major 
engineering challenge in maglev 

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configurations. 
For example, avoiding liner 

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breakup and controlling 
instabilities is crucial. 

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Short confinement time and fast 
disassembly. 

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Because things are compressed so
fast, the plasma tends to fly 

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apart very quickly. 
The fusion burn must occur 

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before the system disassembles. 
That's why pulses, magnetic 

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fields and preheating schemes 
are tightly timed. 

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Scaling to net energy gain. 
So far the Z machine is not a 

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commercial fusion device, it's a
research tool. 

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Achieving break even where 
fusion output is greater than 

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energy input is extremely hard. 
The additional complexity of 

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capturing and sustaining the 
fusion output, handling heat and

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doing that repeatedly is non 
trivial. 

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Lastly, where repeatability and 
cost, the extreme forces, shock 

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waves and mechanical stresses on
the device components require 

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refurbishing and careful design.
The cost per shot in operational

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overhead can be pretty high. 
So how does the Z machine relate

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to the commercial market? 
Here are some recent advances 

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with the first light fusion 
experiment. 

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They recently used the Z machine
to test their amplifier 

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technology and achieve record 
pressures around 10 times the 

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pressures at the Earth's core. 
Next, ongoing development of 

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future versions. 
Sandia is exploring upgrades to 

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allow higher shot rates and 
better performance. 

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Then there's the Z fundamental 
science program. 

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It's where academic and industry
groups can propose experiments 

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on the Z to explore new regimes 
of high energy density physics. 

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Thank you so much for listening 
to the after pop where we break 

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down. 
What the heck is AZ machine? 

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In the blink of a cosmic eye, 
the Z machine stabs a target 

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with electrical power far beyond
everyday comprehension. 

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Every shot is a fleeting feeder 
of extremes. 

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Plasma squeezed to stellar 
intensities, X-rays screaming 

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outward, and atoms push to the 
brink. 

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Yet for all of its power, Z is 
not a power plant. 

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It's a microscope on extremes, a
place where physics is pushed, 

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where materials crack, energies 
collide, and all of our models 

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are stress tested. 
When fusion becomes practical, 

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it may be because we first tamed
a machine like Z and understood 

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the chaos behind the pulse. 
You've been listening to Nega 

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Diggler. 
If you've enjoyed this episode, 

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00:10:04,920 --> 00:10:08,240
please share it with a friend. 
The next shot could light the 

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path to new energy or deeper 
discovery. 

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Until next time, stay curious.