Have you ever heard about collisions in particle accelerators? PART 1
- Alexa Ines Guido
- May 16
- 3 min read
Hola! I'm Alexa Guido, a young and curious woman passionate about science. Join me on an exciting journey to explore the wonders of the universe through the lens of physics.
Have you ever questioned how we’ve come to understand the intricate world of particle physics? How did we unearth the existence of those mind-boggling fundamental particles? Or how do we validate our theories surrounding every fundamental particle? The answer lies in the remarkable collisions occurring within particle accelerators. And by studying these collisions, physicists can probe the world of the infinitely small!
So, what exactly is a particle accelerator? Imagine a colossal machine that propels charged particles, like protons or electrons, at phenomenal speeds, almost reaching the speed of light! These high-energy beams of particles collide with a target or other particles travelling in the opposite direction.
When the particles are sufficiently energetic, something truly extraordinary happens: the energy of the collision is transformed into matter giving rise to new particles, some of which were present in the early universe. This phenomenon is described by Einstein’s iconic equation E=mc2, which reveals that matter is merely a concentrated form of energy, and the two are interchangeable.
But there’s even more going on. In particle physics, the word “collide” doesn't always mean a crash in the traditional sense, it can mean that two protons glide through each other, and their fundamental components pass so close together that they can talk to each other. If their voices are loud enough and resonate just right, they can tap into hidden fields that respond by producing new particles.
As surprisingly as it may seems, space is permeated with dormant fields that can briefly pop a particle into existence when vibrated with the right amount of energy. While these fields play critical roles, they often operate behind the scenes, waiting for the perfect conditions to spring to life. With collitions, we take advantage of this phenomenon and produce brand new particles!
So, why go through the trouble of accelerating particles at all? Once again, Einstein’s formula provides the key. It demonstrates that the energy carried by particles during a collision can be transformed into mass, that is, new particles. Therefore, the higher the collision energy, the heavier and more abundant the particles we can produce.
To better visualize this, imagine a moving object colliding with another identical object at rest, only half of the moving object’s kinetic energy can be used to generate heat or deformation; the rest is retained in motion. However, if two objects are moving towards each other at equal speeds, every bit of kinetic energy is available for heat or deformation at the moment of collision. If the objects stick together, the combination is at rest after the collision. In truth, this is what happens inside these gigantic colliders.
Now, how do we construct these monumental machines? High-energy physics research has continually driven the evolution of particle accelerators. They started life in physics research laboratories in glass envelopes sealed with varnish and putty, with shining electrodes and frequent discharges. Over time, they have transformed into vast facilities that serve large communities, like CERN of FERMI Lab.
The journey toward building these accelerators started in the late 20th century, showcasing the natural progression from atomic physics to nuclear physics and the inevitable need for higher energy and higher intensity "atomic projectiles" than those provided by natural radioactive sources. In this context, the particle accelerator was a planned innovation that achieved the first man-controlled splitting of the atom.
It was Ernest Rutherford, in the early twenties, who realised this need, but the electrostatic machines, then available, were far from reaching the necessary voltage. For a few years, progress stalled. Then, in 1928, when Gurney and Gamov independently predicted tunnelling and it appeared that an energy of 500 keV might just suffice to split the atom. This breakthrough reignited Rutherford’s aspirations, prompting him to encourage Cockcroft and Walton to design a 500 kV particle accelerator.
Four years later in 1932, they split the lithium atom with 400 keV protons. This was the first
fully man-controlled splitting of the atom, which earned them the Nobel prize in 1951. And if you want to learn more about the building of CERN facilities and its history, read “Have you heard about the CERN?
And stay tuned for Part 2, where we’ll explore how particle colliders really work and the fascinating types of accelerators that exist. You won’t want to miss it!
I’d love to hear from you! Feel free to connect with me on LinkedIn!
References:
Images:
Love this!!