The X-ray photons trigger a ‘molecular catapult effect’: light atomic groups are ejected first, similar to projectiles shot from a catapult, while the heavier atoms – bromine and chlorine ...

In this process, the X-ray photons trigger a "molecular catapult effect": light atomic groups are ejected first, similar to projectiles ... and chlorine—are left behind and therefore separate ...

The trebuchet is a type of catapult that was popular for use as a siege engine before gunpowder became a thing. Trebuchets use a long arm to throw projectiles farther than traditional catapults.