由放射性钠衰变产生正电子，冷却后形成一个由大约100万个正电子组成的体积同样大小的粒子云团，这团正电子被存放在相邻的一个容器中。

The positrons, produced by the decay of radioactive sodium, are cooled into a similarly sized cloud of around 1m particles and held in a neighbouring trap.

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这是因为放射性核素在这巨大的爆炸能量中形成，其中一些放射出正电子而衰变。

This is because radioactive nuclear elements are formed in the giant outbursts of energy, and some of these decay by releasing positrons.

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