Magnesium is an alkaline earth metal that is abundant in the Earth’s crust and is also an important component of our diet. Here we are talking about the stable form of the metal, which has 12 protons and 12 neutrons and is referred to as Magnesium-24 (because of a total of 24 protons and neutrons). Interestingly, there can exist other, perhaps not so stable forms of Magnesium that have a different number of neutrons but the same number of protons (12). Such forms are called isotopes of Magnesium.
Until recently, the lightest isotope of Magnesium was Magnesium-19, which had 7 neutrons along with the usual 12 protons. However, this ‘record’ has been broken by a team of researchers at the Michigan State University, who have managed to make Magnesium-18. This isotope is extremely unstable and disintegrates so quickly that scientists cannot directly observe or measure it. Its momentary existence, made possible by using particle accelerators, could help us improve our understanding of how atomic nuclei form and how they remain stable, which would in turn help us get a better idea about how elements are forged in extreme cosmic environments, such as interiors of stars.
How did they make the elusive Magnesium-18? They first took the known, stable Magnesium-24 and accelerated its atoms to half the speed of light. These were then bombarded onto a metal foil made of Beryllium and the collision caused the formation of other Magnesium isotopes. One of these, Magnesium-20, was selected and made to bombard another Beryllium target placed around 30 meters away. Magnesium-20 itself is pretty unstable and decays within 0.1 seconds. Still, since it was travelling at half the speed of light, it was able to bombard the Beryllium target before decaying. This collision finally produces Magnesium-18, which decays inside the Beryllium target within 10-21 seconds (sextillionth of a second). Since scientists cannot examine the isotope directly, they study the end-products of its decay which are Oxygen-14 and a few protons in order to figure out properties of Magnesium-18.
“One of the big questions I’m interested in is where do the universe’s elements come from, how are these elements made? How do these processes happen?” said Kyle Brown, one of the leaders of the study. The newly-formed Magnesium-18 is a step in the direction of refining the models and theories that could answer these questions!
By Gaurav Pundir