Kehlraum

A kehlraum is a specialized scientific device used primarily in inertial confinement fusion (ICF) experiments. The term, derived from German meaning "radiator" or "cavity," refers to a hollow container or cavity designed to produce and direct high-intensity x-ray radiation onto a target fuel pellet.

In ICF, a small spherical or cylindrical pellet containing fusion fuel, typically isotopes of hydrogen such as deuterium and tritium, is compressed and heated to achieve nuclear fusion conditions. The kehlraum surrounds the fuel pellet and is irradiated by high-energy laser beams. When these lasers hit the inner walls of the kehlraum, they produce a burst of x-rays that evenly irradiate and symmetrically compress the fuel pellet, enhancing the likelihood of achieving fusion.

Kehlraums are typically made from high-Z materials such as gold or depleted uranium, which efficiently convert laser energy into x-ray radiation. The design of a kehlraum aims to maximize the uniformity of radiation exposure and minimize asymmetries during compression. This uniformity is crucial for efficient fusion reactions and to prevent instabilities that could disrupt the process.

The development of kehlraums has been vital for advancing inertial confinement fusion research, including experiments conducted at facilities like the National Ignition Facility (NIF) in the United States. Their effectiveness in producing the symmetrical conditions necessary for fusion makes them a key component in the pursuit of practical fusion energy.