Scientists have been closely monitoring the shock waves that have been propagating through some regions of the cosmos for a long time. And they do so because they suspect that they can help us better understand the mechanisms that cause some subatomic particles acquire more energy during his journey through space.
These shock waves are the result of very diverse natural phenomena, such as supernovae, or even something much less violent, such as interaction with the magnetic field of a planet. Whatever its origin, the funny thing is that can contribute to acceleration of some particles to help them reach a speed very close to that of light.
The electrically charged particles that make up the solar wind undergo an acceleration, and therefore an increase in energy, when they interact with the Earth’s magnetic field.
To find ourselves face to face with this phenomenon, we don’t have to go very far. The electrically charged particles that make up the solar wind (protons, electrons, and alpha particles) are accelerated, and therefore an increase in energy, when they interact with the Earth’s magnetic field. However, this phenomenon is more complex than it seems because there are other mechanisms that can also intervene in this increase in energy.
One of them is the relatively abrupt transition that takes place between an essentially empty and cold environment such as space, and another much denser and warmer, such as the atmosphere of our planet. In a way it seems counterintuitive that a particle can undergo an increase in energy as a result of moving from an empty medium to a denser one, but scientists believe that this acceleration is the result of the abrupt transition from one medium to another. Precisely that pressure change it acts as a shock wave capable of deflecting and accelerating the particles.
A small paragraph before moving on. In reality, the emptiness of space it’s a false void. This discussion is outside the scope of this article, but if you are interested in investigating this false void, we can do so in another report. However, if you are curious, you may want to take a look at the text in which we talk about the possibility that the universe originated from the quantum vacuum.
This is how scientists have recreated this phenomenon in the laboratory
A research group that brings together scientists who carry out their teaching activities in French, Italian, Russian, Canadian, Czech and Romanian universities has published a very interesting article in Nature Physics in which it explains in detail how you managed to recreate in the laboratory, on a small scale, of course, the interaction that occurs when subatomic particles are exposed to a shock wave of a cosmic nature.
The experiment carried out by these researchers has achieved that the protons of a gas acquire a maximum energy of 80,000 eV
The idea is relatively simple. What they have done has been to use a high-power laser to abruptly and very intensely heat a gas, transforming it into plasma. Then this extremely hot gas has been injected into a hydrogen cloud, so that the interaction of the particles of both gases results in the appearance of a shock wave. In doing so, the protons of the colder gas have undergone an acceleration, acquiring a maximum energy of 80 000 eV (electron volts). This is not a unit of energy that we are used to handling, but it is good for us to know that it is a lot of energy.
This experiment cannot be considered definitive because it is not enough to fully understand the mechanisms that explain how subatomic particles acquire more energy when they travel through the cosmos. But at least it’s helping scientists better understand some of those mechanisms. There is no doubt that this is an important advance. Now what we have to do is the same as always: continue investigating to hunt down other phenomena that perhaps also contribute their bit to the mysterious push suffered by some of the particles that travel through the universe.
Cover image | POT
More information | Nature Physics