Soft photon
= Soft photon
{wiki=Soft_photon}
In particle physics, a "soft photon" refers to a type of photon that has relatively low energy and, as a result, long wavelength. The term is often used in the context of quantum electrodynamics (QED) and scattering processes. Soft photons are particularly relevant in discussions about radiation emitted during high-energy processes, such as the collisions of charged particles.