The size of the LHC is huge, future accelerator’s
designs are even bigger.
They all use conventional technologies.
We are at a certain
limit now, so we are really interested in
decreasing these sizes again but still having
the same energy.
And this is exactly the context of AWAKE.
We work on a technology where we can accelerate
particles much much stronger, which allows
us to decrease the size of accelerators and
at the same time having the same energy.
In conventional accelerators we use
so-called cavities.
These are essentially metal boxes, or cylinders,
under vacuum.
And we have an oscillating electric field
which is excited by an electromagnetic energy
which we put into.
In plasma wakefield accelerations, we use
plasma.
Plasma is not vacuum, plasma is a kind of
fourth state of matter where we have ions
and free electrons.
And this field, we get by having a particle
beam, a very strong beam passing through this
plasma and exciting these fields, which are
called wakefields.
The beam which we can use is a very strong
laser or electrons or a proton beam, and that’s
exactly what we are using in AWAKE.
The interesting thing also why we are using
these protons is that these protons have a
very high energy.
So they penetrate very deep into the plasma
and can also accelerate particles to very
high energies in one go.
In the AWAKE experiment we have now reached
two milestones.
Last year we have shown for the very first
time that we can produce wavefields in plasma
with a proton beam.
This means that the proton beam is like a
boat, it goes through the plasma, and it creates
our wakefields, the waves there.
This has been shown for the first time and
this year now we’ve injected an electron
beam into these wavefields and these electrons
finally got accelerated.
So again, it is like surfers which we inject
into these waves and they surf along
and get accelerated.
And our electrons have now been accelerated
to 2 GeV over 10 metres.
That’s very impressive because it is already
a factor of 40 times higher than what we have
in LHC, using conventional technologies there.
For this year’s programme is very important
to carry out very well-defined measurements
in order to gauge the experiment versus simulations.
This is very important because the better
we know our entire set-up, the better we can
predict and design the next steps.
In the coming years then, we want to show
that we can accelerate electrons very strong,
meaning 1 GeV over 1 metre, and at the same
time keeping the electron beam quality.
And then, of course, we want to show the scalability,
meaning we want to accelerate electrons to
several GeV over several metres, in order
then, at the end, to design a high-energy
physics accelerator based on this technology.
