ackretionsskiva

An accretion disk, also known as an accretion disc, is a structure formed by diffuse material in orbital motion around a central body. The central body is typically a star or black hole. Accretion disks are common in a variety of astrophysical contexts, including proto-planetary disks, active galactic nuclei, and X-ray binary star systems. The material in an accretion disk spirals inward due to the effects of viscosity and angular momentum transfer, eventually accreting onto the central object. This process can release a significant amount of energy, often in the form of electromagnetic radiation, making accretion disks important sources of light in the universe. The temperature and density of the material in an accretion disk increase as it approaches the central object, leading to the emission of radiation across a wide range of wavelengths. Accretion disks are studied using various observational techniques, including spectroscopy, photometry, and interferometry, to better understand the physical processes at work and the role they play in the evolution of stars and galaxies.