闪电是如何产生正电子的？ 第1页

Photodisintegration - Wikipedia

灵活运用网上各种资料也是一个必备的技能了。

所谓的光核反应，其实就是光子和带电原子核之间通过电磁相互作用发生碰撞或吸收的一个过程。

至于在雷闪放电过程中发生的光核反应，题主链接中的摘要已经说的很清楚了：

Lightning and thunderclouds are natural particle accelerators1. Avalanches of relativistic runaway electrons, which develop in electric fields within thunderclouds2,3, emit bremsstrahlung γ-rays. These γ-rays have been detected by ground-based observatories4,5,6,7,8,9, by airborne detectors10 and as terrestrial γ-ray flashes from space10,11,12,13,14. The energy of the γ-rays is sufficiently high that they can trigger atmospheric photonuclear reactions10,15,16,17,18,19 that produce neutrons and eventually positrons via β+ decay of the unstable radioactive isotopes, most notably 13N, which is generated via 14N + γ → 13N + n, where γ denotes a photon and n a neutron.

光核反应之所以会发生，是因为雷雨云中的电子发生了韧致辐射产生了γ光子。这些γ光子会和大气中的各种原子核发生光核反应。