Scientists working on the ALICE experiment at the Large Hadron Collider (LHC) in Switzerland in the collisions of atomic nuclei of lead, they unexpectedly produced a small amount of gold. However, it was not a large amount. According to scientists, the total amount of gold created reached approximately 29 trillionths of a gram.
Physicists tried to imitate the conditions that prevailed shortly after the Big Bang. When the lead nuclei were accelerated to a speed close to the speed of light and their mutual collisions occurred a strong electromagnetic field that could rip protons out of some nuclei. This is the key to the entire transformation. A lead atom contains three more protons than a gold atom. If a lead nucleus loses exactly three protons, gold is formed.
The authors explain that this mainly occurred when two nuclei passed closely. Scientists did not directly observe the gold. In the experiment, they use special detectors called zero-angle calorimeters that count protons knocked out of lead nuclei. The existence of gold cores is therefore inferred indirectly from the measured data.
According to the calculations of the ALICE experiment, approximately 89,000 gold nuclei are produced per second during operation. In addition to gold, other elements were also recorded. The removal of one proton from lead leads to the formation of thallium, the loss of two protons then forms mercury.
It is interesting that the creation of gold does not represent any advantage for the scientists themselves. Nuclei that lose protons deviate from their original path and collide with the walls of the accelerator within a few microseconds. Thereby, they gradually weaken the intensity of the particle beam. As the authors emphasize, understanding this unplanned alchemy is important not only for the correct interpretation of current experiments, but also for the design of even larger accelerators of the future.
