strålingen

Strålingen is the energy that travels through space or matter as waves or particles. In scientific usage, strålingen covers both electromagnetic radiation—from radio waves to gamma rays—and, in broader terms, energetic particle emission such as alpha and beta radiation. The study of strålingen includes how it is produced, propagates, and interacts with matter, a subject central to radiative transfer, optics, and nuclear physics.

Electromagnetic radiation spans the spectrum from long-wavelength radio waves to short-wavelength gamma rays. Particle radiation consists of fast-moving atomic nuclei, electrons, or other subatomic particles released by radioactive decay or nuclear reactions. Natural sources include the Sun, stars, radioactive minerals, and cosmic rays; artificial sources include electrical lighting, X-ray equipment, nuclear reactors, accelerators, and lasers.

Key properties are wavelength or frequency and energy per quantum. Interactions with matter include absorption, reflection, scattering, and transmission. The amount or distribution of radiation incident on a surface is described by irradiance or radiance, and spectral distributions by spectral irradiance. Biological effects depend on dose, measured in gray (Gy) or sievert (Sv).

Applications include communications (radio and microwaves), medical imaging and therapy (X-rays, radiation therapy), industrial processing, astronomy, and climate science. In climate, strålingen refers to the balance between incoming solar radiation and outgoing infrared radiation, a central factor in the Earth's energy budget that is affected by greenhouse gases and clouds.

Safety and regulation address limits, shielding, and monitoring to protect people and the environment from excessive exposure.