The Large Hadron Collider ran by CERN, more colloquially known as the LHC, makes frequent appearances on popular science media. From television to newspapers, the LHC is regarded in one of two ways: as a scientifically revolutionary machine that will find answers to the most sought-after questions; or as an overly-expensive world-ending black-hole-creating science experiment. There are sceptics trying to sway those who are unfamiliar with the particle collisions occurring hundreds of millions of times a second around the LHC’s 27-kilometre diameter ring. However, most people would agree that the answer to such a debate lies in the middle of those differing opinions.
Aerial view of Cern - Credit: CERN
Protons were the LHC’s bread and butter, as countless collisions occurred with this subatomic particle. However, it wasn’t until July of this year that CERN made news with another world-first: the acceleration and successful collision of atoms in the LHC.
More specifically, the recent endeavour was done with ions: lead atoms, but with one electron. The reason why scientists are reaching into unknown territory is because, as LHC engineer Michaela Schaumann puts it: “We’re investigating new ideas of how we could broaden the present CERN research programme… Finding out what is possible is the first step,” (1). The lead ions were accelerating with average power around the particle accelerator, which lies under the French-Swiss border for approximately two minutes, until a stable beam of the ions was achieved. The beam’s energy was then increased to full capacity. The lead ions were able to circulate for over two hours before the power was turned off. The trial proved to be a tremendous success and a lot was learnt from the initial experiments. The successful test opened “new research opportunities in a vast domain of uncharted fundamental physics,” according to the physicist behind the idea – Witold Krasny (2).
The LHC is the largest particle accelerator in the world, and has the capability to accelerate particles, such as lead ions, to near light speeds. Extremely high energies can be reached this way, which lead to the production of gamma rays. Krasny put forward the idea of the ‘Gamma Factory’ in 2015. The underlying thought behind the ‘Gamma Factory’ is the infamous equation E=mc2, which states that mass and energy are equivalent. It is notoriously difficult to produce in laboratories because gamma rays are very high energy light particles with enormous applications. The proposal of a ‘Gamma Factory’ was nothing but a far-fetched dream before the incredible people at CERN were able to accelerate the lead ions around the LHC. With the record-breaking mass being accelerated, huge energy gamma rays can be formed – which can be applied to countless unexplored areas of science (2).
One specific opportunity the physicists at CERN are interested in is the study of the dark matter particle. Although no massive plans have been released yet to study this illusive subject, it will only be a matter of time before the scientists at CERN have devised a plan. The dark matter particle is a mystery to the scientific community which can only be believed to be achieved with the application of higher energy rays such as gamma rays. Dark matter is believed to make up around 27% of the universe, however it is still one of the most mysterious and confusing topics for physicists. It does not interact with light, it cannot be seen, but its effects can be observed within galaxies and large-scale structures in space (3). Many theories try to explain the nature of dark matter, but no experimental data has been collected so far. The ‘Gamma Factory’ could be our best way to create dark matter here on Earth in controlled environments so that it can be studied. The high energy gamma rays produced by the ‘Gamma Factory’ can be transformed into massive particles such as dark matter particles: energy and mass are essentially the same thing, as shown by the infamous aforementioned equation E=mc2 (1).
A bridge of dark matter - Credit: CERNCOURIER
As these were the first tests of this kind, producing dark matter from the gamma rays created by accelerated high mass particles is a fairly long way off in the future, but it is the first step into furthering this kind of research with the technology available to us. However, if we can produce these particles it would be a massive step forward in the scientific community. We would be able to learn so much more about the composition of dark matter, and why and how it naturally exists in our universe. CERN and the LHC are slowly working towards solving these questions that have baffled physicists for decades, and as technology is constantly evolving, this could be possible sooner than we think.
- LHC accelerates its first “atoms”. S. Charley. [Online] [Cited: August 9, 2018.] https://home.cern/about/updates/2018/07/lhc-accelerates-its-first-atoms
- The Gamma Factory proposal for CERN. W. Krasny. [Online] [Cited: August 9, 2018.] https://arxiv.org/abs/1511.07794
- Dark matter. CERN. [Online] [Cited: August 28, 2018.] https://home.cern/about/physics/dark-matter