Producing light and using it to analyze matter is too simple a phrase to summarize what happens inside a synchrotron. However, if we specify something more and say that a ray brighter than the sun is produced – which, in addition, travels at the speed of light -, and then use it to look at what happens inside the atoms of matter, we will be more close to understanding the complexity of what happens inside the Alba Synchrotron particle accelerator.
This accelerator located in Cerdanyola del Vallès (Barcelona) is one of the largest scientific infrastructures on the Peninsula and one of the most important in southern Europe. Since it opened in 2012, hundreds of scientists and companies from all over the world come here every year to carry out the most varied experiments. In fact, to date there have been 2,500 different experiments and more than 1,300 articles from specialized magazines have been published.
Thanks to this powerful instrument, it has been possible, for example, to see exactly what happens to a cell when it is infected by the covid-19 virus or to see where the antibiotics are located within each cell. You can also observe how a cosmetic behaves on the skin; assist in the restoration of wall paintings centuries old; develop specific drugs or identify the causes of Alzheimer’s; know the materials inside the Earth; develop packaging for gastronomy, or develop all types of materials for energy storage batteries, etc.
How do they do it?
The building is a circumference of almost 300 meters in diameter which is a bit reminiscent of a “ninja star”. Inside, one of the phenomena that occurs in the stars is reproduced, the so-called synchrotron light. Caterina Biscardi, director of ALBA, details: «Here we produce synchrotron light, which is nothing more than the light emitted by charged particles, which have a lot of energy and move in non-linear trajectories. It would be a bit like X-rays, although in reality, we reproduce a part of the electromagnetic spectrum, from infrared to x-rays including visible light. Let’s say that this natural phenomenon that occurs in the universe, in black holes for example, we reproduce it here but in a controlled way within the accelerator. By mastering this beam of electrons, we take advantage of the light they emit to carry out experiments with such powerful resolution that we can see what a cell looks like inside with a level of detail of just 30 nanometers. “This allows us to see the position of the atoms and what state they are in.”
The process begins with a simple metal tablet, specifically tungsten impregnated with barium oxide (BaO). When heated to 1,200 degrees, They extract electrons that accelerate. «To do this, electric fields are used, while to ensure that they follow circular trajectories, magnets are used. The light emitted by the electrons is diverted towards windows where it goes to different experimental laboratories,” continues the director of ALBA.
Inside the laboratories, called lines, something different is investigated. Right now there are 14 active studies of drugs, lithium batteries, but also other materials that are being developed for energy storage and electric cars, tomography to see the cell in 3D, etc. This coming year, other lines will be incorporated.
Extension
For three years, ALBA has been transforming, a process that will culminate in 2032 when the third generation accelerator is replaced by a fourth generation one. ALBA II will further increase analytical capacity, because its resolution will go from 30 nanometers to 2-3 nanometers. «We will change the internal accelerator to make the electron beam much smaller, more focused. Now the dimension of the electron beam is like a hair. With ALBA II it will be 10 times smaller and that will produce a much more intense beam of photons with greater capacity; something that will also increase the speed of the experiments,” says Biscardi.