fusion cross-section

Fusion cross-section is a measure of the likelihood that two atomic nuclei will combine (fuse) when they collide. Think of it as an effective target area representing the probability of fusion occurring during a collision at a specific energy level. A larger cross-section means a higher chance of fusion. This concept helps scientists understand and predict how easily nuclear reactions happen under different conditions, such as those in the Sun or in fusion reactors. It is a key parameter in studying nuclear energy and reactions.