The CERN particle accelerator, which will revitalise physics

 February 21, 2023

You enter a small, brutalist building at CERN, Europe's particle physics laboratory on the outskirts of Geneva, Switzerland, to get to Edda Gschwendtner's experiment. You enter the lift and fall 50 metres into a vast underground chamber. After passing through a series of yellow security doors, you must walk a kilometre downhill through a tunnel, which is why Gschwendtner usually rides one of the small white bikes parked inside the doors.

She is working on a promising type of particle accelerator that could aid in the discovery of new physics. Particle physics hasn't made much progress since the discovery of the Higgs boson in 2012. As a result, thoughts are turning to machines that can assist us in probing reality in various ways.

The AWAKE experiment, on which Gschwendtner is working, generates a wave of plasma—a gas of charged particles—and sends electrons surfing along it. While most colliders are becoming larger and more expensive, this underground machine and others like it, known as plasma wakefield accelerators, are becoming smaller and more affordable. But don't be fooled by their diminutive size—they pack a powerful punch. In comparison to CERN's massive Large Hadron Collider (LHC), plasma wakefield technology can achieve much higher accelerations over a given distance. "Up to a factor of 1,000 more," Gschwendtner claims.

It appears to be working. AWAKE has had a string of successes in accelerating electrons over a few metres in recent years. Last year, it passed a crucial test, and researchers are now gearing up to take it to higher energies. …

By : NEW SCIENTIST